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Kniestedt, Christoph. "Tonometry through the ages = Tonometrie im Wandel der Zeit /." Zürich, 2007. http://opac.nebis.ch/cgi-bin/showAbstract.pl?sys=000253361.
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Silva, Marcelo Jordão Lopes da. "Influencia da idade, espessura central da cornea e do indice de qualidade na tonometria de contorno dinamico." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/309857.
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Orientador: Vital Paulino CostaTese (doutorado)- Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
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Resumo: Os objetivos deste trabalho são comparar a pressão intra-ocular (PIO), medida com tonometria de contorno dinâmica (TCD) e tonometria de aplanação de Goldmann (TAG), analisar a influência da espessura central da córnea (ECC) e idade, em ambas as medições, bem como a influência do índice de qualidade sobre as leituras da TCD. Foram avaliados 500 indivíduos saudáveis (1000 olhos), sem história prévia de glaucoma ou hipertensão ocular (idade: 7 a 86 anos) recrutados consecutivamente. TAG, TCD e ECC foram obtidos de ambos os olhos de cada indivíduo, nessa ordem, por três observadores. A média de cinco medidas da ECC foi utilizada para análise. As medições da TCD foram aceitas quando o escore de qualidade variou entre 1 (qualidade superior) e 3 (menor qualidade). A média das PIOs obtidas com TCD foram superiores em 3,2 mmHg às medições com TAG. A análise de Bland-Altmann revelou má concordância entre as leituras de TCD e TAG, com intervalos de confiança de 95% de ± 6,98 mmHg. Os valores da ECC variaram entre 449 e 653 µm. As PIOs medidas com TAG mostraram-se fortemente correlacionadas à ECC (r? = 0,28, p <0,001), enquanto as PIOs obtidas com TCD apresentaram fraca correlação com a ECC (r2 = 0,01, p = 0,017). Tanto as medidas de TCD (r2 <0,01, p = 0,044) quanto as obtidas com TAG (r2 = 0,01, p <0,001) apresentaram fraca correlação com a idade. Os escores de qualidade das medidas de TCD foram 1 (n = 369, 36,9%), 2 (n = 340, 34,0%) e 3 (n = 291, 29,1%). As leituras de medida com TCD com escore de qualidade 3 (18,8 ± 3,4 mmHg) foram significativamente maiores do que aquelas com escore 1 (16,7 ± 2,9 mmHg) e 2 (17,4 ± 2,9 mmHg) (p <0,001). Concluiu-se que a medida com TCD não é influenciada pela ECC, ao contrário daquela com TAG. As medidas de PIO tomadas com TCD e com TAG não são influenciados pela idade. Finalmente, medidas de TCD com qualidade inferior apresentam valores maiores que as de qualidade superior.
Abstract: The purposes of this study are to compare the IOP measurements obtained with dynamic contour tonometry (DCT) and Goldmann applanation tonometry (GAT), and to analyze the influence of central corneal thickness (CCT) and age on both measurements, and the influence of the quality score on DCT readings. 500 healthy subjects with no previous history of glaucoma or ocular hypertension (ages: 7 to 86 years old) were consecutively recruited. GAT (Haag Streit R900, Switzerland), DCT (SMT Swiss Micro Technology, Switzerland), and CCT (Sonomed Micropach 200P+, USA) measurements were obtained from both eyes of each individual, in this order, by three observers. The mean of five CCT measurements was used for analysis. DCT measurements were accepted when quality scores varied between 1 (higher quality) and 3 (lower quality). In our series, the mean DCT measurements were 3.2 mmHg higher than GAT readings. CCT values varied between 449 and 653 µm. IOP measured by GAT correlated strongly with CCT (r2=0.28, p<0.001), whereas DCT readings correlated poorly with CCT (r2=0.01, p=0.017). Both DCT (r2<0.01, p=0.044) and GAT (r2=0.01, p<0.001) measurements correlated poorly with age. Bland-Altmann analysis revealed disagreement between DCT and GAT readings, with 95% confidence intervals of ± 6.98 mmHg. Quality scores for DCT measurements were 1 (n=369, 36.9%), 2 (n=340, 34.0%) and 3 (n=291, 29.1%). DCT readings with quality score of 3 (18.77±3.35 mmHg) were significantly higher than those with quality scores of 1 (16.61±2.91 mmHg) and 2 (17.44±2.93 mmHg) (p<0.001). In conclusion, DCT is not influenced by CCT, unlike GAT. Both DCT and GAT measurements are not influenced by age. DCT measurements with lower quality scores are associated with higher readings.
Doutorado
Doutor em Ciências Médicas
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Hallberg, Per. "Applanation Resonance Tonometry for Intraocular Pressure Measurement." Doctoral thesis, Umeå : Tillämpad fysik och elektronik, Umeå univ, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-784.
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Vandivier, Suzette D. (Suzette Denise) 1978. "An exploration of through-the-eyelid tonometry." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/86746.
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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.Includes bibliographical references (leaves 44-45).
by Suzette D. Vandivier.
M.Eng.
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Hamilton, Kirsten School of Optometry & vVsion Science UNSW. "Corneal hydration and the accuracy of Goldmann tonometry." Awarded by:University of New South Wales. School of Optometry and vVsion Science, 2006. http://handle.unsw.edu.au/1959.4/30468.
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The purpose of this thesis was to investigate the effect of corneal swelling on the accuracy of Goldmann tonometry estimates of intraocular pressure (IOP). In the first experiment, central corneal thickness (CCT, ultrasonic pachymetry), IOP (Goldmann tonometry) and corneal curvature (keratometry) was measured in one eye of 25 subjects every two hours for 24 hours, except for 8 hours overnight (no measurements taken), and for the first two hours after awakening (measurement frequency 20 minutes). CCT (+20.1??10.9 pm) and IOP (+3.1??2.4 mmHg) peaked on eye opening, and then decreased at a similar rate (r=0.967, p<0.001) for the next two hours. Corneal swelling may have influenced the accuracy of Goldmann IOP measurements during this time. In the second and third studies, the CCT, IOP and corneal curvature were measured in both eyes of two groups of 25 subjects before and after the induction of corneal swelling, resulting from two hours of monocular closed eye contact lens wear. The increase in IOP was correlated to the increase in CCT at a rate of 0.33 to 0.48 mmHg per 10 pm, which signified an overestimation error in Goldmann IOP measurement. However, the change in IOP could not be accounted for solely by the change in CCT. In the fourth study, CCT, IOP and corneal curvature were used in conjunction with the Orssengo-Pye algorithm to determine the range of Young's modulus in the normal population, which was 0.29??0.06 MPa. Physiological variations in Young's modulus had a similar effect on Goldmann tonometry to CCT. In the fifth study, the data collected for studies 2 and 3 was used to calculate the Young's modulus changes associated with corneal swelling, again with the assistance of the Orssengo-Pye algorithm. No systematic change in Young's modulus was recorded after contact lens wear, but the model suggested that corneal biomechanical changes were responsible for the remainder of the change in IOP. All experimental results were combined to develop a model to calculate the diurnal variation of Goldmann IOP errors. The likely error in IOP due to overnight corneal swelling was 0.6 to 1.4 mmHg, which may explain as much as 45% (1.4 mmHg) of the 3.1 mmHg diurnal variation of IOP. In summary, small amounts of corneal swelling were shown to have a clinically significant impact on the accuracy of Goldmann tonometry. This may interfere with the measurement of the diurnal variation of IOP, particularly if measurements are taken prior to the resolution of overnight corneal swelling.
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McCafferty, Sean, Jason Levine, Jim Schwiegerling, and Eniko T. Enikov. "Goldmann and error correcting tonometry prisms compared to intracameral pressure." BIOMED CENTRAL LTD, 2018. http://hdl.handle.net/10150/626542.
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Background: Compare Goldmann applanation tonometer (GAT) prism and correcting applanation tonometry surface (CATS) prism to intracameral intraocular pressure (IOP), in vivo and in vitro. Methods: Pressure transducer intracameral IOP was measured on fifty-eight (58) eyes undergoing cataract surgery and the IOP was modulated manometrically to 10, 20, and 40 mmHg. Simultaneously, IOP was measured using a Perkins tonometer with a standard GAT prism and a CATS prism at each of the intracameral pressures. Statistical comparison was made between true intracameral pressures and the two prism measurements. Differences between the two prism measurements were correlated to central corneal thickness (CCT) and corneal resistance factor (CRF). Human cadaver eyes were used to assess measurement repeatability. Results: The CATS tonometer prism measured closer to true intracameral IOP than the GAT prism by 1.7+/-2.7 mmHg across all pressures and corneal properties. The difference in CATS and GAT measurements was greater in thin CCT corneas (2.7+/-1.9 mmHg) and low resistance (CRF) corneas (2.8+/-2.1 mmHg). The difference in prisms was negligible at high CCT and CRF values. No difference was seen in measurement repeatability between the two prisms. Conclusion: A CATS prism in Goldmann tonometer armatures significantly improve the accuracy of IOP measurement compared to true intracameral pressure across a physiologic range of IOP values. The CATS prism is significantly more accurate compared to the GAT prism in thin and less rigid corneas. The in vivo intracameral study validates mathematical models and clinical findings in IOP measurement between the GAT and CATS prisms.
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Wang, Defu. "Biomechanical simulation of the human cornea with applications in tonometry." Thesis, University of Dundee, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.505612.
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Booysen, Dirk. "Tonometry and biomechanics of the cornea in contact lens wear." Thesis, Aston University, 2016. http://publications.aston.ac.uk/30151/.
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Aims: Research on use of contact lenses as drug delivery systems continues. Disposable lenses are often used to treat corneal injuries. Accurate intraocular pressure (IOP) measurements with lenses in situ will enhance patient care and save valuable chair time. Inter- and intraobserver reliability of rebound tonometer (RBT) and intraobserver reliability of ocular response analyser (ORA) with and without contact lenses of 50 (15 male, 35 female) healthy well adapted contact lens wearers between 18 – 55 years (M = 38.90, SD = 9.23) were examined. Clinical comparisons of IOP measurements with ORA and RBT were done. Accuracy of IOP measurements with four commonly prescribed disposable contact lenses (Acuvue Oasys, Frequency XC, Acuvue 1-Day Moist, and Pure Vision with powers -6.00 − +6.00 D) in situ was evaluated. Physiological and physical factors influencing IOP measurements with both instruments were determined. Findings: Intraobserver reliability of RBT without and with lenses was excellent (ICC > 0.88; > 0.92 respectively). Interobserver reliability of RBT was excellent without or with lenses (ICC 0.81; 0.88 respectively). Intraobserver reliability of ORA was good for all metrics measured except for corneal hysteresis (CH) (ICC: CH 0.63; corneal resistance factor (CRF) 0.79; corneal compensated IOP (IOPcc) 0.77; IOPg 0.87).RBT and ORA IOPg (Goldmann equivalent IOP) measurements were clinically and statistically comparable without or with lenses (differences < 0.6 mmHg). ORA IOPcc and RBT were less comparable (differences < 1.45 mmHg).Accurate RBT and ORA tonometry (within 2 mmHg) was possible with low minus power (range -0.50 to -6.00 D); moderate modulus of elasticity (< 0.75 MPa); thin silicone hydrogel (Acuvue Oasys) and hydrogel (Frequency XC; Acuvue 1-Day Moist) contact lenses in situ. Multiple regression analyses showed biomechanical metrics CRF and CH affected RBT and ORA (IOPcc and IOPg) measurements strongly (p < 0.0001). Therefore, cornea’s biomechanical properties had greater influence on accuracy of IOP measurements with these two instruments than other variables examined.
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Yamane, Iris de Souza. "Avaliação de parâmetros tomográficos de córnea e segmento anterior e de variáveis desencadeadas pela resposta ocular à tonometria de não contato." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/5/5149/tde-10102012-103707/.
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OBJETIVO: avaliar e correlacionar parâmetros tomográficos de segmento anterior e parâmetros biomecânicos de córnea entre si, com a idade e o gênero de pacientes com olhos normais. MÉTODOS: um estudo clínico de série de casos com intervenção diagnóstica foi realizado, envolvendo um olho selecionado aleatoriamente de 235 pacientes (235 olhos). Os pacientes foram submetidos a exame oftalmológico completo, incluindo avaliação tomográfica (Pentacam) e biomecânica (ORA). Parâmetros avaliados pelo Pentacam: K1, K2, K Front Max , Astig, ISV, IVA, KI, CKI, IHA, IHD, BAD D, BAD Df, BAD Db, BAD Dp, BAD Dt, BAD Dy, ART Max, ART Avg, ART Min, Enh BFS Front 8mm, Enh BFS Back 8mm, Ele F BFS 8mm Apex, Ele F BFS 8mm Thinnest, Ele F BFS 8mm Max 4mm zone, Ele B BFS 8mm Apex, Ele B BFS 8mm Thinnest, Ele B BFS 8mm Max 4mm zone, Ele F BFTE 8mm Apex, Ele F BFTE 8mm Thinnest, Ele F BFTE 8mm 4 mm zone, Ele B BFTE 8mm Apex, Ele B BFTE 8mm Thinnest, Ele B BFTE 8mm Max 4mm zone, RPI Max, RPI Avg, RPI Min, Diff RPI Max Compl, Diff RPI Min Compl, Pachy Min, Pachy Apex, Pachy Pupil, Rel Pachy Min, Asph Q Front 30º, Asph Q Back 30º, Q Asymmetr Frontal Hor 30º, Q Asymmetr Frontal Vert 30º, AC Depth, AC Volume, Ch Angle, Volume, PNS, Densid Avg %. Parâmetros avaliados pelo ORA: IOPg, IOPcc, CH, CRF, KC Score, KC Normal, KC Suspect, KC Mild, KC Moderate, KC Severe, WS, aindex, bindex, p1area, p2area, aspect1, aspect2, uslope1, uslope2, dslope1, dslope2, w1, w2, h1, h2, dive1, dive2 , path1, path2, mslew1, mslew2, slew1, slew2, aplhf, p1area1, p2area1, aspect11, aspect21, uslope11, uslope21, dslope11, dslope21, w11, w21, h11, h21, path11, path21. RESULTADOS: K1, K2, K Max Front, BAD Df, Ele B BFS 8mm Thinnest, Ele B BFTE 8mm Thinnest, CRF e CH apresentaram valores mais altos no sexo feminino, enquanto BAD Db, Enh BFS Front 8mm, AC Depth, AC Volume, Ch Angle, p1area, w2, h1, p1area1, w21 e h11 apresentam valores mais altos no sexo masculino. CKI, BAD Db, Ele F BFS 8mm Apex, Ele F BFS 8mm Thinnest, Ele F BFTE 8mm Apex, Ele F BFTE 8mm Thinnest, Asph Q Back 30º, AC Depth, Ch Angle mostraram forte correlação negativa com a idade. Ele B BFS 8mm Apex, Ele B BFS 8mm Thinnest, Ele B BFTE 8mm Apex, Ele B BFTE 8mm Thinnest mostraram forte correlação positiva com a idade. As correlações mais altas de CH e CRF ocorreram com BAD Dt, Pachy Min, Pachy Apex e Pachy Pupil, ou seja, CH e CRF apresentaram associação positiva com a espessura corneana central. As correlações mais altas da IOPg ocorreram com BAD Dt, ART Max, ART Avg, Pachy Min, Pachy Apex e Pachy Pupil mostrando ser afetada pela espessura corneana. A IOPcc mostrou correlações mais baixas do que as obtidas com a IOPg, sendo esta menos afetada pela espessura corneana. CONCLUSÃO: Os parâmetros tomográficos de segmento anterior (Pentacam) e biomecânicos (ORA) mostraram diversas associações estatisticamente significantes entre si com a idade e com o gênero de pacientes com olhos normaisPURPOSE: to evaluate and to correlate anterior segment tomography parameters and corneal biomechanical parameters between each other, age and gender in patients with healthy eyes. METHODS: a clinical study of case series design with diagnostic intervention was conducted, involving one eye randomly selected from 235 patients (235 eyes). Patients underwent complete ophthalmological examination, including tomographic (Pentacam) and biomechanical (ORA) evaluation. Pentacam parameters assesssed: K1, K2, K Front Max , Astig, ISV, IVA, KI, CKI, IHA, IHD, BAD D, BAD Df, BAD Db, BAD Dp, BAD Dt, BAD Dy, ART Max, ART Avg, ART Min, Enh BFS Front 8mm, Enh BFS Back 8mm, Ele F BFS 8mm Apex, Ele F BFS 8mm Thinnest, Ele F BFS 8mm Max 4mm zone, Ele B BFS 8mm Apex, Ele B BFS 8mm Thinnest, Ele B BFS 8mm Max 4mm zone, Ele F BFTE 8mm Apex, Ele F BFTE 8mm Thinnest, Ele F BFTE 8mm 4 mm zone, Ele B BFTE 8mm Apex, Ele B BFTE 8mm Thinnest, Ele B BFTE 8mm Max 4mm zone, RPI Max, RPI Avg, RPI Min, Diff RPI Max Compl, Diff RPI Min Compl, Pachy Min, Pachy Apex, Pachy Pupil, Rel Pachy Min, Asph Q Front 30º, Asph Q Back 30º, Q Asymmetr Frontal Hor 30º, Q Asymmetr Frontal Vert 30º, AC Depth, AC Volume, Ch Angle, Volume, PNS, Densid Avg %. ORA Parameters assessed: IOPg, IOPcc, CH, CRF, KC Score, KC Normal, KC Suspect, KC Mild, KC Moderate, KC Severe, WS, aindex, bindex, p1area, p2area, aspect1, aspect2, uslope1, uslope2, dslope1, dslope2, w1, w2, h1, h2, dive1, dive2 , path1, path2, mslew1, mslew 2, slew1, slew2, aplhf, p1area1, p2area1, aspect11, aspect21, uslope11, uslope21, dslope11, dslope21, w11, w21, h11, h21, path11, path21. RESULTS: K1, K2, K Max Front, BAD Df, Ele B BFS 8mm Thinnest, Ele B BFTE 8mm Thinnest, CRF and CH showed higher values in females and BAD Db, Enh BFS Front 8mm, AC Depth, AC Volume, Ch Angle, p1area, w2, h1, p1area1, w21 and h11 showed higher values in males. CKI, BAD Db, Ele F BFS 8mm Apex, Ele F BFS 8mm Thinnest, Ele F BFTE 8mm Apex, Ele F BFTE 8mm Thinnest, Asph Q Back 30º, AC Depth, Ch Angle showed strong negative correlation with age. Ele B BFS 8mm Apex, Ele B BFS 8mm Thinnest, Ele B BFTE 8mm Apex, Ele B BFTE 8mm Thinnest showed strong positive correlation with age. The highest correlations of CH and CRF occurred with BAD Dt, Pachy Min, Pachy Apex and Pachy Pupil, i.e. CH and CRF presented positive association with central corneal thickness. The highest correlations of IOPg occurred with BAD Dt, ART Max, ART Avg, Pachy Min, Pachy Apex and Pachy Pupil, showing that it is affected by the thickness of the cornea. IOPcc showed lower correlations than those obtained with IOPg, showing that it is less affected by the thickness of the cornea. CONCLUSION: Anterior segment tomographic parameters (Pentacam) and biomechanical parameters (ORA) showed several statistically significant associations between each other, age and gender in patients with healthy eyes
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Claros, Chacaltana Flor Diana Yokoay. "Avaliação da pressão intraocular em chinchilas (chinchilla Lanigera) de diferentes faixas etárias utilizando tonometria de rebote." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/76540.
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A aferição da pressão intraocular (PIO) é fundamental durante o exame oftálmico. Objetivou-se estabelecer os valores de referência da PIO de chinchilas de diferentes faixas etárias utilizando o tonômetro de rebote. A PIO foi aferida ao longo do dia às 7, 12 e 19 horas utilizando o tonômetro de rebote (Tonovet®). As chinchilas foram subdivididas em três grupos com 12 animais cada, considerando as idades, designados por GI (animais com idade entre dois a seis meses), GII (com idade entre 20 e 34 meses) e GIII (animais com idade entre 37 e 135 meses). Previamente, foram realizados teste da lágrima de Schirmer, prova da fluoresceína, biomicroscopia com lâmpada de fenda e oftalmoscopia indireta em todos os animais. O valor médio da pressão intraocular encontrado foi 2,49 ± 0,56 mmHg, os valores médios para o grupo I foi de 2,47±0,581 mmHg, no grupo II de 2,47±0,581 mmHg e no grupo III de 2,51±0,531 mmHg. Não foram encontradas diferenças significativas entre a idade e a PIO (P = 0,756). Não foram encontradas diferenças significativas entre as horas do dia e a PIO (P = 0,415). Não foram encontradas diferenças significativas entre os sexos (P = 0,857). Os valores da PIO em chinchilas não sofrem alterações decorrentes do sexo e da idade dos animais. Não ocorre influência do ritmo circadiano na PIO de chinchilas.The assessment of intraocular pressure (IOP) is essential for the ocular examination. The purpose of this study was to establish reference values of intraocular pressure chinchillas (Chinchilla lanigera) of different age groups. Thirty-six Chinchillas were divided in three groups of 12 animals each, considering the ages designated by GI (animals aged two to six months), GII (aged between 20 and 34 months) and GIII (animals aged between 37 and 135 months). Intraocular pressure was measured at 7, 12 and 19 hours. Tear production was measured, fluorescein test, slit-lamp biomicroscopy and indirect ophthalmoscopy in all animals and IOP was measured using the rebound tonometer (Tono Vet®) set on the P (undefined species) setting, with measurements obtained from each eye. No abnormalities were found on ophthalmic examination. The mean (±SD) of IOP was 2.49 ± 0.56 mmHg, with a range of 2-4 mmHg. The mean (±SD) of IOP for group I, II and III were 2.47 ± 0.581 mmHg, 2.47 ± 0.581 mmHg and 2,51 ± 0.531 mmHg, respectively. No significant differences were found between age and IOP and no significant differences were found between the hours of day and IOP. No significant differences were found between the genders. The IOP in chinchillas is unchanged between genders and age of the animals. The circadian rhythm is not influenced by IOP in chinchillas.
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McCafferty, Sean, Garrett Lim, William Duncan, Eniko Enikov, Jim Schwiegerling, Jason Levine, and Corin Kew. "Goldmann tonometer error correcting prism: clinical evaluation." DOVE MEDICAL PRESS LTD, 2017. http://hdl.handle.net/10150/624648.
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Purpose: Clinically evaluate a modified applanating surface Goldmann tonometer prism designed to substantially negate errors due to patient variability in biomechanics. Methods: A modified Goldmann prism with a correcting applanation tonometry surface (CATS) was mathematically optimized to minimize the intraocular pressure (IOP) measurement error due to patient variability in corneal thickness, stiffness, curvature, and tear film adhesion force. A comparative clinical study of 109 eyes measured IOP with CATS and Goldmann prisms. The IOP measurement differences between the CATS and Goldmann prisms were correlated to corneal thickness, hysteresis, and curvature. Results: The CATS tonometer prism in correcting for Goldmann central corneal thickness (CCT) error demonstrated a reduction to <+/- 2 mmHg in 97% of a standard CCT population. This compares to only 54% with CCT error <+/- 2 mmHg using the Goldmann prism. Equal reductions of similar to 50% in errors due to corneal rigidity and curvature were also demonstrated. Conclusion: The results validate the CATS prism's improved accuracy and expected reduced sensitivity to Goldmann errors without IOP bias as predicted by mathematical modeling. The CATS replacement for the Goldmann prism does not change Goldmann measurement technique or interpretation.
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Wan, Abdul Halim Wan Haslina. "Tonometry agreement and corneal biomechanical features in normal, glaucomatous and keratoconic eyes." Thesis, Aston University, 2017. http://publications.aston.ac.uk/31760/.
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Intraocular pressure measurement is a routine clinical examination performed in ophthalmic practice. It is vital in clinical monitoring, diagnosis and management of certain eye diseases. There are many types of tonometers currently available to measure the intraocular pressure (IOP). These tonometers employ different technologies compared to the standard Goldman applanation tonometer (GAT). Studies often report inter-tonometry agreement and bias of new tonometers against GAT. However, only a minority have studied the proportionate bias and factors that influence the inter-tonometry bias of a new tonometer. The inter-tonometry agreement is vulnerable to the influence of corneal physical and mechanical properties. The information on reliability and agreement between different tonometers is very important in the management of ocular diseases. The aim of this thesis was to examine the inter-tonometry agreement between five different tonometers. The influence on IOP of demographic and ocular factors was investigated. This thesis investigates the biomechanical characteristics of the cornea of normal, glaucomatous and keratoconus subjects and the factors that influence biomechanical parameters. The tonometers employed were found to have a good agreement with GAT but the tonometry values were not interchangeable. The bias of each tonometer was influenced differently by central corneal thickness (CCT), specific corneal biomechanical parameters and age. Clinicians should be cautious when examining glaucoma and keratoconus patients with different tonometers, as most demonstrate significant proportionate bias. The corneal biomechanical parameters in subjects with different ocular diagnoses revealed variable significance and was influenced by age, CCT and corneal curvature. Future research to identify unique corneal parameters in different ocular conditions may be of importance especially in screening and diagnosis.
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Lupinacci, Alvaro Pedroso de Carvalho. "Estudo caso-controle de paquimetria corneana central em indivíduos com catarata congênita e afacia pós-cirúrgica." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/312260.
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Orientador: Vital Paulino CostaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: O presente estudo teve como objetivo medir a espessura corneana central (ECC) de indivíduos com catarata congênita e afacia cirúrgica após extração de catarata congênita. Indivíduos com catarata congênita ou afacia cirúrgica após cirurgia de catarata congênita foram recrutados prospectivamente e divididos em quatro grupos: catarata unilateral (n=14), catarata bilateral (n=18), afacia unilateral (n=32) e afacia bilateral (n=44). Um grupo controle foi selecionado a partir de indivíduos normais pareados por idade, gênero e etnia. Paquimetria ultrassônica foi realizada pelo mesmo observador com o aparelho Micropach 200P+ (Sonomed, Lake Success, Nova Iorque, EUA), após anestesia tópica com uma gota de oxibuprocaína 0,4%. Registrou-se a média de cinco medidas para cada olho. A ECC média do grupo controle (513,57±23,32µm) não foi significativamente diferente da média dos olhos contralaterais normais (526,36±38,52µm) (p=0,747) e dos olhos com catarata (527,00±36,03µm) (p=0,252) do grupo catarata unilateral. A ECC média de ambos os olhos do grupo catarata bilateral (olho direito: 547,69±34,17µm; olho esquerdo: 545,88±36,69µm) foi maior que a observada no grupo controle (olho direito: 516,06±18,66µm; olho esquerdo: 515,53±17,43µm) (p<0,01). A média da ECC dos olhos afácicos (597,25±44,14µm) no grupo afacia unilateral foi significativamente maior que as observadas nos olhos contralaterais saudáveis (523,47±21,42µm) e no grupo controle (511,81±18,81µm) (p<0,001). Ambos os olhos do grupo afacia bilateral apresentaram ECC média (olho direito: 615,75±61,03µm; olho esquerdo: 618,91±61,86µm) significativamente maior que no grupo controle (olho direito: 515,59±18,80µm; olho esquerdo: 515,86±18,51µm) (p<0,001). Observou-se ECC média significativamente maior nos olhos afácicos (uni e bilaterais) que nos olhos com catarata (uni e bilaterais) (p<0,001). Olhos afácicos após extração de catarata congênita apresentam córneas mais espessas que olhos fácicos normais. Olhos afácicos após cirurgia de catarata congênita também apresentam córneas mais espessas que olhos com catarata congênita, sugerindo que o aumento da espessura corneana central ocorra após a cirurgia
Abstract: This study aimed to measure the central corneal thickness (CCT) of patients with congenital cataract and surgical aphakia post congenital cataract extraction. Individuals with congenital cataract or aphakia after surgery for congenital cataract were recruited prospectively and divided into four groups: unilateral cataract (n=14), bilateral cataracts (n=18), unilateral aphakia (n=32) and bilateral aphakia (n=44). A control group was selected from healthy individuals matched for age, gender and ethnicity. Ultrasonic pachymetry was performed by the same observer with the Micropach 200P+ pachymeter (Sonomed, Lake Success, New York, USA) after topical anesthesia with a drop of oxybuprocaine 0.4%. The average of five measurements for each eye was recorded for the analysis. The mean CCT of the control group (513.57±23.32µm) was not significantly different from the contralateral normal eyes (526.36±38.52µm) (p=0.747) and eyes with cataract (527.00±36.03µm) (p=0.252) of the unilateral cataract group. The mean CCTs of both eyes in the bilateral cataract group (right eye: 547.69±34.17µm; left eye: 545.88 ± 36.69µm) were significantly thicker than the observed in the control group (right eye: 516.06±18.66µm; left eye: 515.53±17.43µm) (p<0.01). The mean CCT of aphakic eyes (597.25±44.14µm) in the unilateral aphakia group was significantly thicker than those observed in healthy contralateral eyes (523.47±21.42µm) and the control group (511.81±18.81µm) (p<0.001). Both eyes of the bilateral aphakia group had mean CCT (right eye: 615.75±61.03µm; left eye: 618.91±61.86µm) significantly thicker than the control group (right eye: 515.59±18.80µm; left eye: 515.86±18.51µm) (p<0.001). The mean CCT was significantly thicker in aphakic eyes (unilateral and bilateral) than in eyes with cataract (unilateral and bilateral) (p<0.001). Aphakic eyes after congenital cataract extraction have thicker corneas than normal phakic eyes and eyes with congenital cataract. This suggests that increased central corneal thickness occurs after congenital cataract extraction surgery
Doutorado
Oftalmologia
Doutor em Ciências Médicas
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Otsuki, Denise Aya. "Hemodiluição normovolêmica aguda: estudo experimental comparativo utilizando amido hidroxietílico a 6% ou solução de Ringer lactato." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/10/10137/tde-03022005-113414/.
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Hemodiluição normovolêmica aguda é um procedimento utilizado para diminuir a necessidade de transfusões sangüíneas em diversas cirurgias de grande porte. Poucos trabalhos avaliam as alterações hemodinâmicas e perfusão tecidual através de estudo ecocardiográfico e tonometria gástrica. Foram utilizados 23 porcos (peso 46.6 ± 6.0 kg) anestesiados com quetamina, fentanil e propofol e instrumentados para monitorização hemodinâmica convencional. Os animais foram randomizados em três grupos 30 minutos após estabilização da anestesia: Grupo I (Controle), Grupo II (amido hidroxietílico) e Grupo III (Ringer lactato). Os animais do grupo II e III foram submetidos ao protocolo de hemodiluição com hematócrito alvo de 15%. A retirada de sangue foi realizada em 30 minutos e a expansão plasmática feita simultaneamente com amido hidroxietílico ou Ringer lactato nas proporções de 1:1 ou 1:3 em relação ao sangue retirado. Os parâmetros hemodinâmicos e de oxigenação, pH gástrico, ecocardiografia transesofágica (fração de ejeção através do método Simpson) foram coletados antes da hemodiluição (T0), no fim do procedimento de hemodiluição (T1) e após uma e duas horas (T2, T3). Os dados foram submetidos a análise de variância para medidas repetidas, seguida pelo teste Tukey e teste T student. Resultados: Em relação aos parâmetros do grupo controle, não houve diferença significante durante todo o procedimento. No grupo II e grupo III, houve aumento no índice cardíaco após hemodiluição (T0=5,80±1,46; T1=10,64±1,69 L.min-1.m2 e T0=5,53±1,18, T1=7,91±1,40 L.min-1.m2 respectivamente), e diminuição do índice de resistência vascular sistêmica (T0=1753±336, T1=822±140 dina.s.cm-5.m-2 e T0=1673±566, T1=1026±190 dina.s.cm-5.m-2 respectivamente), ambos estatisticamente significante. A fração de ejeção apresentou aumento significativo após a hemodiluição no grupo II. O pH gástrico diminuiu significativamente no grupo III. O lactato arterial aumentou de forma significante no grupo III após a hemodiluição. A microscopia eletrônica do ventrículo esquerdo mostraram discreta destruição de miofilamentos no grupo II. Houve destruição importante nas miofibrilas no grupo III. Conclusão: Estes resultados sugerem que na hemodiluição moderada a grave, o amido hidroxietílico consegue preservar melhor a estabilidade hemodinâmica do que a solução de Ringer lactato.Normovolemic acute hemodilution is a procedure utilized to decrease the needs of blood transfusion during a variety of surgical procedures. Nevertheless, there are few works that evaluate its pulmonary effects as well as hemodynamic changes by means of echocardiography and tonometric evaluation. Methods: 23 anesthetized pigs (weight 46.6 ± 6.0 kg) were instrumented for standard hemodynamic monitoring. In order to prevent possible effects of inhaled anesthetics on pulmonary mechanics, intravenous anesthesia was chosen and consisted of ketamine, fentanyl and propofol administered throughout the study. Thirty minutes after anesthesia stabilization animals were randomized in three groups: Group I (Control), Group II (hydroxyethyl starch) and Group III (Lactated Ringers). Animals of group II and III were submitted to acute normovolemic hemodilution to reach a pre-established hematocrit around 15%. Blood withdrawal was accomplished in thirty minutes and plasma expansion was performed simultaneously with hydroxyethyl starch or Lactated Ringers administered in a proportion of 1:1 or 3:1 in relation to the amount of bloods withdrawn. Hemodynamic, gastric pH, transesophageal echography (ejection fraction, by Simpon method) and oxygen transport were measured before blood withdrawal (T0), at the end of hemodilution (T1), one and two hours after the end of hemodilution (T2, T3). Data were submitted to analysis of Variance for repeated measures followed by the Tukey test and also to a student T test. Results: In regard to all parameters of Group I (Control), there were no significant difference during the whole procedure. In Group II and Group III, there was an increase in cardiac index after hemodilution (T0=5.80±1.46; T1=10.64±1.69 L.min-1.m2 and T0=5.53±1.18, T1=7.91±1.40 L.min-1.m2), and a decrease in systemic vascular resistance index (T0=1753±336, T1=822±140 dyne.s.cm-5.m-2 and T0=1673±566, T1=1026±190 dyne.s.cm-5.m-2), both statistically significant. Ejection Fraction increased significantly after hemodilution in group II. Gastric pH decreased significantly in Group III, and arterial lactate increased significantly after hemodilution in group III. Electron microscopy of left ventricular bipsies showed a slight destruction in filament and preserved myofibrillar ultrastructure in group II. There was important destruction in myofibrillar ultrastructure in group III. Conclusion: These results suggest that in severe hemodilution, hydroxyethyl starch preserves hemonodynamic stability better than Lactate Ringers.
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Moreno, Tatiana Martinez. "Pressão intraocular média obtida por três diferentes avaliadores utilizando os tonômetros de rebote e de aplanação em equinos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/143945.
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A mensuração da pressão intraocular (PIO) é essencial para o exame oftálmico, pois permite o diagnóstico de doenças oftálmicas como uveíte e glaucoma, além de auxiliar no monitoramento das cirurgias intraoculares. Objetivou-se comparar a tonometria de rebote com a tonometria de aplanação em equinos. Além disso, determinar a reprodutibilidade dos valores obtidos em ambos os aparelhos. A PIO foi aferida em 30 equinos da raça Crioula, machos ou fêmeas, com idade entre um e 16 anos utilizando o tonômetro de rebote (TonoVet®) e o tonômetro de aplanação (Tonopen Avia®). Previamente a aferição da PIO, todos os animais foram submetidos ao exame oftálmico incluindo, avaliação dos reflexos pupilares, teste da lágrima de Schirmer, prova da fluoresceína e biomicroscopia com lâmpada de fenda portátil. Foram utilizados apenas bulbos oculares hígidos. A análise estatística foi feita com ANOVA e teste t de Student. A reprodutibilidade foi avaliada pelo cálculo do coeficiente de correlação intraclasse (ICC). A média da PIO foi de 26,16 ± 5,13 mmHg utilizando o tonômetro de rebote e de 22,55 ±7,32 mmHg com o tonômetro de aplanação. A média da PIO de acordo com o avaliador utilizando o tonômetro de rebote foi de 25,27 ± 4,9 mmHg para o examinador A, 25,80 ± 5,2 mmHg para o examinador B e de 27,40 ± 5,1 mmHg para o examinador C. Com o tonômetro de aplanação as médias obtidas foram de 20,03 ± 4,5 mmHg com o examinador A, 19,67 ± 6,0 mmHg com o examinador B e de 27,97 ± 10,3 mmHg com o examinador C (p<2,3). O ICC foi de 0,18 para o tonômetro de aplanação e de 0,41 para o tonômeto de rebote. Os valores da pressão intraocular média obtidos com o tonômetro de rebote são superestimados quando comparados aos valores obtidos com o tonômetro de Tonopen Avia® em equinos saudáveis. Comparativamente ao Tonopen Avia® os valores obtidos com o Tonovet® demonstraram maior reprodutibilidade.The measurement of intraocular pressure (IOP) is essential for the ophthalmic examination, as it allows the diagnosis of eye diseases such as uveitis and glaucoma, as well as aid in the monitoring of intraocular surgery. This study aimed to compare the mean intraocular pressure (IOP) values in horses obtained by three different examiners using the rebound and applanation tonometer’s. Each examiner measured the IOP of 30 “Crioulo” horses, males or females, aged one to 16 years old, using rebound tonometer and applanation tonometer. Previous to the experiment an ophthalmic examination was performed in horses. Only animals without alterations were selected. Three veterinarians measured IOP with rebound (Tonovet®) and applanation tonometer’s (TonoPen Avia®). Comparisons were made using ANOVA and student t test. Intraclass correlation coefficient (ICC) was calculated for reproducibility. IOP measurements resulted in mean values of 26.16 ± 5.13 mmHg for rebound tonometer and 22.55 ±7.32 mmHg for applanation tonometer. These values were different on statistical analysis. Rebound tonometer mean values, according with the examiner, were: A 25.27 ± 4.9 mmHg, B 25.80 ± 5.2, C 27.40 ± 5.1 mmHg. For applanation tonometer the mean IOP for examiner A (20.03 ± 4.5 mmHg), B (19.67 ± 6.0 mmHg), C (27.97 ± 10.3 mmHg). With the Tonopen Avia® tonometer examiner C measured higher IOP’s than examiners A and B. Intraclass correlation coefficient was 0.41 for rebound tonometer was 0.18 for applanation tonometer. It was observed that the values obtained with the Tonovet® were overestimated compared to Tonopen Avia® in healthy horses. When compared with Tonopen Avia® values obtained with the Tonovet® showed a higher reproducibility.
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McCafferty, Sean, Eniko Enikov, Jim Schwiegerling, and Sean Ashley. "Goldmann tonometry tear film error and partial correction with a shaped applanation surface." DOVE MEDICAL PRESS LTD, 2018. http://hdl.handle.net/10150/626544.
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Purpose: The aim of the study was to quantify the isolated tear film adhesion error in a Goldmann applanation tonometer (GAT) prism and in a correcting applanation tonometry surface (CATS) prism. Methods: The separation force of a tonometer prism adhered by a tear film to a simulated cornea was measured to quantify an isolated tear film adhesion force. Acrylic hemispheres (7.8 mm radius) used as corneas were lathed over the apical 3.06 mm diameter to simulate full applanation contact with the prism surface for both GAT and CATS prisms. Tear film separation measurements were completed with both an artificial tear and fluorescein solutions as a fluid bridge. The applanation mire thicknesses were measured and correlated with the tear film separation measurements. Human cadaver eyes were used to validate simulated cornea tear film separation measurement differences between the GAT and CATS prisms. Results: The CATS prism tear film adhesion error (2.74 +/- 0.21 mmHg) was significantly less than the GAT prism (4.57 +/- 0.18 mmHg, p<0.001). Tear film adhesion error was independent of applanation mire thickness (R-2=0.09, p=0.04). Fluorescein produces more tear film error than artificial tears (+0.51 +/- 0.04 mmHg; p<0.001). Cadaver eye validation indicated the CATS prism's tear film adhesion error (1.40 +/- 0.51 mmHg) was significantly less than that of the GAT prism (3.30 +/- 0.38 mmHg; p=0.002). Conclusion: Measured GAT tear film adhesion error is more than previously predicted. A CATS prism significantly reduced tear film adhesion error by similar to 41%. Fluorescein solution increases the tear film adhesion compared to artificial tears, while mire thickness has a negligible effect.
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Frampton, Peter. "Tonometry : a study in biomechanical modelling : appraisal and utility of measurable biomechanical markers." Thesis, Aston University, 2017. http://publications.aston.ac.uk/33115/.
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Goldmann Applanation Tonometry (GAT) is the recognised ‘Gold Standard’ tonometer. However this status is refuted by eminent authors. These contradictory views have driven the initial goal to assess, from first principles, the evolution of GAT and to experimentally evaluate its utility and corrections. Subsequently, an important caveat became the evaluation of Corneal Hysteresis and Corneal Resistance Factor. Chapter 1. Biomechanical building blocks are defined and constitutive principles incorporated into continuum modelling. The Imbert-Fick construct is re-interpreted a simple biomechanical model. GAT corrections are also appraised within a continuum framework; CCT, geometry and stiffness. These principles enable evaluation of alternative tonometer theory and the evolving biomechanical markers, Corneal Hysteresis (ORA-CH) and Corneal Resistance Factor (ORA-CRF). Chapter 2 appraises corneal biomechanical markers, CCT, curvature, ORA-CH and ORA-CRF in 91 normal eyes and the impact these have on three tonometers: GAT, Tonopen and Ocular Response Analyser (ORA). Tonopen was the sole tonometer not affected by biomechanics. CCT was confirmed the sole measurable parameter affecting GAT. ORA did not demonstrate improved utility. ORA-CH and ORA-CRF do not appear robust biomechanical measures. Chapter 3 assessed agreement between GAT, the ORA measures and Tonopen. Tonopen is found to measure highest and raises the question should a development goal emphasise GAT agreement or improvement? Chapter 4 assessed repeatability of the three tonometers and biomechanical measures keratometry, pachymetry, ORA-CH and ORA-CRF on 35 eyes. Coefficients of Repeatability (CoR) of all tonometers are wide. Effects assessed in Chapter 5 may be masked by general noise. ORA does not appear to enhance utility over GAT. Isolation of corneal shape change via Orthokeratology (Chapter 5) demonstrate ORACH and ORA-CRF reflect, predominantly, a response to corneal flattening. It is proposed they do not significantly reflect corneal biomechanics. After reviewing models for tear forces (Chapter 6), a refined mathematical model is presented. Tear bridge attraction is minimal and cannot explain under-estimation of IOP by GAT in thin corneas. CCT corrections and the Imbert-Fick rules are incompatible. Chapter 7 summarises findings. The supremacy of GAT is likely to remain for some time, reflecting the sheer magnitude of overturning 60 years of convention, historical precedent, expert opinion as well as the logistical and educational difficulties of redefining standards and statistical norms.
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Swoboda, Marek Lec Ryszard Joseph Jeffrey. "Implantable arterial blood pressure sensor /." Philadelphia, Pa. : Drexel University, 2004. http://hdl.handle.net/1860/2968.
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McCafferty, Sean, Garrett Lim, William Duncan, Eniko Enikov, and Jim Schwiegerling. "Goldmann Tonometer Prism with an Optimized Error Correcting Applanation Surface." ASSOC RESEARCH VISION OPHTHALMOLOGY INC, 2016. http://hdl.handle.net/10150/622594.
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Purpose: We evaluate solutions for an applanating surface modification to the Goldmann tonometer prism, which substantially negates the errors due to patient variability in biomechanics. Methods: A modified Goldmann or correcting applanation tonometry surface (CATS) prism is presented which was optimized to minimize the intraocular pressure (lOP) error due to corneal thickness, stiffness, curvature, and tear film. Mathematical modeling with finite element analysis (FEA) and manometric lOP referenced cadaver eyes were used to optimize and validate the design. Results: Mathematical modeling of the optimized CATS prism indicates an approximate 50% reduction in each of the corneal biomechanical and tear film errors. Manometric lOP referenced pressure in cadaveric eyes demonstrates substantial equivalence to GAT in nominal eyes with the CATS prism as predicted by modeling theory. Conclusion: A CATS modified Goldmann prism is theoretically able to significantly improve the accuracy of lOP measurement without changing Goldmann measurement technique or interpretation. Clinical validation is needed but the analysis indicates a reduction in CCT error alone to less than +/- 2 mm Hg using the CATS prism in 100% of a standard population compared to only 54% less than +/- 2 mm Hg error with the present Goldmann prism. Translational Relevance: This article presents an easily adopted novel approach and critical design parameters to improve the accuracy of a Goldmann applanating tonometer.
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McCafferty, Sean, Jason Levine, Jim Schwiegerling, and Eniko T. Enikov. "Goldmann applanation tonometry error relative to true intracameral intraocular pressure in vitro and in vivo." BIOMED CENTRAL LTD, 2017. http://hdl.handle.net/10150/626266.
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Background: Goldmann applanation tonometry (GAT) error relative to intracameral intraocular pressure (IOP) has not been examined comparatively in both human cadaver eyes and in live human eyes. Futhermore, correlations to biomechanical corneal properties and positional changes have not been examined directly to intracameral IOP and GAT IOP. Methods: Intracameral IOP was measured via pressure transducer on fifty-eight (58) eyes undergoing cataract surgery and the IOP was modulated manometrically on each patient alternately to 10, 20, and 40 mmHg. IOP was measured using a Perkins tonometer in the supine position on 58 eyes and upright on a subset of 8 eyes. Twenty one (21) fresh human cadaver globes were Intracamerally IOP adjusted and measured via pressure transducer. Intracameral IOP ranged between 5 and 60 mmHg. IOP was measured in the upright position with a Goldmann Applanation Tonometer (GAT) and supine position with a Perkins tonometer. Central corneal thickness (CCT) was also measured. Results: The Goldmann-type tonometer error measured on live human eyes was 5.2 +/- 1.6 mmHg lower than intracameral IOP in the upright position and 7.9 +/- 2.3 mmHg lower in the supine position (p <.05). CCT also indicated a sloped correlation to error (correlation coeff. = 0.18). Cadaver eye IOP measurements were 3.1+/-2. 5 mmHg lower than intracameral IOP in the upright position and 5.4+/- 3.1 mmHg in the supine position (p <.05). Conclusion: Goldmann IOP measures significantly lower than true intracameral IOP by approximately 3 mmHg in vitro and 5 mmHg in vivo. The Goldmann IOP error is increased an additional 2.8 mmHg lower in the supine position. CCT appears to significantly affect the error by up to 4 mmHg over the sample size.
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Bargiotas, Ioannis. "Development of Image Processing Methods to Extract Biomarkers of Aortic Aging from MRI and Applanation Tonometry." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066338.
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Aorte est l'artère qui amortit et conduit le flux sanguin éjecté par le cœur en flux continu vers la périphérie. Avec l’âge, l'élasticité aortique diminue en association avec des altérations fonctionnelles et hémodynamiques de l’aorte et du cœur. Alors que l'hémodynamique artérielle a été largement étudiée par l'analyse des courbes de pression, les modifications de l’onde de débit aortique n’ont été que très peu explorées. L’imagerie IRM, couplée à une segmentation appropriée, permet une évaluation non-invasive et précise du débit sanguin aortique. Cette thèse combine ce débit mesuré en IRM avec les pressions tonométriques afin de proposer des indices quantitatives de rigidité artérielle. Ainsi, ce travail comprend: Une nouvelle approche, basée sur les ondelettes, pour estimer le temps de transit entre les ondes de flux provenant de deux sites aortiques. Ce dernier a permis de calculer la vitesse de l'onde de pouls dans la crosse, qui s’est avérée être un marqueur fort de la rigidité et de l’âge. Une analyse d'impédance aortique dans le domaine fréquentiel pour quantifier la charge pulsatile et les réflexions qui augmentent la charge exercée sur le cœur. Une quantification de la forme de l'onde de débit aortique, dont l’association avec les changements géométriques du cœur a été montrée. Une cartographie des pressions intra-aortiques absolues en utilisant les équations de Navier-Stokes. Ces nouveaux indices ont été testés sur 70 sujets sains et leur complémentarité en termes de caractérisation de l’âge et du couplage entre l'aorte et le cœur a été montrée. De futures études sur l'hypertension artérielle permettront de démontrer l'utilité clinique de nos indicesAorta is the artery which immediately accommodates the blood flow ejected from the heart. It buffers blood’s pulsatile momentum and conducts it smoothly towards periphery. With physiological aging, aortic elasticity diminishes significantly in association with aortic or cardiac functional and hemodynamic alterations. While aortic hemodynamics were widely studied through pressure curves analysis, proximal aorta flow patterns were only little investigated. Recent developments of cardiovascular magnetic resonance imaging (MRI) and image segmentation tools, enable an accurate non-invasive evaluation of proximal aortic blood flow. This thesis combined MRI with central pressure measurements by applanation tonometry to propose flow-indices of arterial stiffness. Indeed our work proposed: A new wavelet-based method, which enables temporal localization of signal frequencies to estimate transit-time between flow waves from two aortic sites, in order to derive aortic arch pulse wave velocity, which is a strong marker of stiffening and aging. An aortic impedance analysis in frequency domain to provide indices which reflect changes in aortic pulsatile load and wave reflection, which augments the load on the heart Quantitative flow-morphology indices which were shown to be associated with age-related changes in left heart geometry. Absolute intra-aortic pressure mapping using the Navier-Stokes equations. These new indices have been tested on 70 healthy volunteers and findings indicated their complementary nature in characterizing aging and aortic-heart coupling. Further investigations in the context of hypertension will prove the clinical usefulness of our indices
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Joy, Joshan. "Noninvasive measures of abdominal muscular function in low back pain /." [St. Lucia, Qld], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18236.pdf.
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Pisa, Ana Rita da Costa. "Tonometria em aves de rapina : aspectos da sua aplicação na prática clínica." Master's thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2011. http://hdl.handle.net/10400.5/3604.
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Dissertação de Mestrado Integrado em Medicina VeterináriaUma apreciação correcta e atempada da pressão intraocular (PIO) é crítica para a avaliação de alterações oculares como o glaucoma e uveíte. Na prática clínica esta é realizada recorrendo à sua medição indirecta através da tonometria. No entanto, para que esta tenha valor diagnóstico, o clínico necessita conhecer os valores normais de PIO das espécies examinadas. Neste estudo foi realizada a tonometria de aplanamento com recurso ao Tono-Pen VET® (Reichert Technologies, 230635V, Nova Iorque, E.U.A.), para estimar a PIO em 40 Peneireiros das torres (Falco naumanni) e 12 Peneireiros comuns (Falco tinnunculus), animais residentes no Grupo de Rehabilitación de la Fauna Autóctona y su Hábitat (GREFA) em Madrid, Espanha. Antes da tonometria foi realizado um exame físico e oftalmológico completo a todas as aves, garantindo o seu estado hígido para integração neste estudo. As medições tonométricas foram realizadas após a aplicação de uma gota de anestésico tópico (hidrocloreto de oxibuprocaína e hidrocleto de tetracaína, Colircusi Anestesico Doble®, Laboratórios Alcon, Barcelona, Espanha) na superfície corneana dos animais. A média (± DP) de PIO no Peneireiro das torres foi de 11,4 ± 2,7 mmHg (68 olhos) e de 13,9 ± 3,5 mmHg (22 olhos) no Peneireiro comum. Não se encontraram efeitos significativos na mesma entre sexos, idades, olho direito e esquerdo e o número da medição para ambas as espécies. Foram encontradas diferenças significativas entre espécies (teste de duas amostras de Wilcoxon, P=0,017). Alguns aspectos inerentes à técnica tonométrica foram ainda avaliados, em relação aos quais, se verificou que a temperatura do ambiente em que se efectuaram as medições tonométricas tinha efeito na PIO, o qual foi significativo (teste de duas amostras de Wilcoxon, P=0,047). Sugere-se ainda, que a realização de medições pode beneficiar da crescente experiência do utilizador no manuseamento do tonómetro. Em geral, a tonometria de aplanamento demonstrou ser um método diagnóstico da PIO com aplicabilidade e facilidade de utilização bem como, apresentou um boa aceitação por parte das aves de rapina abordadas. No entanto, ao não existir um instrumento ideal para cada animal, é uma técnica que deve considerar a variabilidade existente entre espécies, indivíduos e utilizadores.
ABSTRACT - TONOMETRY IN BIRDS OF PREY – ASPECTS OF ITS APPLICATION IN THE CLINICAL PRACTICE - An accurate and early assessment of intraocular pressure (IOP) is essential for evaluating ocular disorders such as glaucoma and uveitis. In the clinical practice this is accomplished by its indirect measure through tonometry. Nevertheless, for it to be of diagnostic value the clinician must know the normal values of the examined species. In this study applanation tonometry was performed using the Tono-Pen VET® (Reichert Technologies, 230635V, New York, U.S.A.), to estimate IOP in 40 Lesser kestrels (Falco naumanni) and 12 Common kestrels (Falco tinnunculus), resident animals of the Grupo de Rehabilitación de la Fauna Autóctona y su Hábitat (GREFA), in Madrid, Spain. Before the tonometry, a complete physical and ophthalmological examination was carried out in all birds ensuring their healthy state for inclusion in this study. Tonometric measurements were performed after application of one drop of topical anesthetic (oxybuprocaine hydrochloride and tetracaine hydrochloride, Colircusi Anestesico Doble®, Alcon Laboratories, Barcelona, Spain) on the animals’ corneal surface. Mean (± SD) IOP in the Lesser kestrel was 11,4 ± 2,7 mmHg (68 eyes) and 13,9 ± 3,5 mmHg (22 eyes) in the Common kestrel. There were no significant effects between sex, age, right and left eye or reading number on the IOP measured in any of the species. Significant differences were found between species (Two-sample Wilcoxon, P=0,017). Some inherent aspects to the tonometry technique were also evaluated, for which it was found that the environment temperature in which the measurements took place had a significant effect on the IOP (Two-sample Wilcoxon, P=0,047). It is also suggested that the performance of measurements can benefit from the growing user experience in handling the tonometer. In general, applanation tonometry has proven to be an IOP diagnostic method with great application, easy use and showing a good acceptance by the bird of prey patient. However, since there isn’t an ideal instrument for each animal, it is a technique that must consider the variability among species, individuals and users.
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Andrade, Maria Cristina Caldart de. "Estudo comparativo entre a tonometria de rebote e a tonometria de aplanação em equinos da raça crioula (Equus cabbalus)." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/49695.
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A aferição da pressão intraocular (PIO) é importante para o diagnóstico e acompanhamento de doenças oculares. Métodos fidedignos para quantificar a PIO de maneira acurada têm sido buscados. Com o aparecimento de tonômetros portáteis, a avaliação da pressão intraocular em equinos tem se intensificado e os diferentes princípios de aferição têm sido comparados. Este estudo objetivou a comparação entre a tonometria de aplanação, realizada com o Tono-Pen Avia®, e tonometria de rebote, realizada com o Tonovet®, em equinos da raça Crioula. Além disso, a utilização, ou não, do cachimbo como método de contenção também foi comparada e submetida à análise estatística. Foram avaliados 30 cavalos com idades entre dois e 20 anos, machos ou fêmeas. Exame oftálmico prévio foi realizado com teste da lágrima de Schirmer, prova da fluoresceína, biomicroscopia com lâmpada de fenda e oftalmoscopia direta. A tonometria de aplanação foi realizada, no mínimo, 30 minutos após a tonometria de rebote. A pressão intraocular média do Tonovet® foi maior, 36,82 ± 5,91mmHg com cachimbo e 30,04 ± 3,19mmHg sem. A do Tono-Pen Avia® foi de 26,43 ± 5,48 mmHg com cachimbo e 23,10 ±4,01mmHg sem. Todos os resultados diferiram estatisticamente entre si. Quando comparados os sexos, o Tono-Pen Avia® não mostrou diferenças, enquanto o Tonovet® mostrou pressões maiores para cavalos castrados e garanhões, e menores para éguas (p<0,001) com a utilização do cachimbo. Não há correlação entre a idade dos cavalos e os valores de PIO, independente do aparelho (p > 0,05). Os valores da PIO com o Tonovet® foram maiores do que os obtidos com o Tono-Pen Avia®. A contenção dos animais com cachimbo eleva a pressão intraocular em equinos.Intraocular pressure evaluation is important for diagnosis and control of ophthalmic diseases. Accurate methods to quantify intraocular pressure have been searched. With the development of handheld tonometers, equine intraocular pressure evaluation has been intensified and the different principles of measurement have been compared. The objective of this study was to compare the applanation tonometry, taken with the Tono- Pen Avia® and the rebound tonometry, taken with the Tonovet® in adult “crioulo” breed horses. The age, gender and the use of upper lip twitch as a restraint method was also surveyed and submitted to statistical analysis. Thirty horses, aged two to 20, male or female were evaluated. A previous ophthalmic examination was performed with Schirmer tear test, fluoresceine test, slit lamp biomicroscopy and direct ophthalmoscopy in all animals. Applanation tonometry was performed, at least, 30 minutes after rebound tonometry. Intraocular pressure mean values measured with the Tonovet® was higher, 36,82±5,91mmHg with the lip twitch and 30,04±3,19mmHg without. Tonopen Avia® mean values were 26,43±5,48mmHg with the lip twitch and 23,10±4,1mmHg without. All results was statistical different between themselves. When genders were compared the Tono-Pen Avia® revealed no difference, however the Tonovet® showed higher pressures for male horses (p‹0,001) with the use of lip twitch. There was no correlation between age and intraocular pressure in “crioulo” horses, regardless of the equipment tested (p›0,05). Intraocular pressure mean values measured with the Tonove®t were higher than those obtained with the Tono-Pen Avia®. The restraint of animals with upper lip twitch increases equine intraocular pressure.
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Medina, Flavio Mac Cord 1978. "Reprodutibilidade do teste de sobrecarga hidrica realizado em diferentes horarios do dia." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/310115.
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Orientadores: Jose Paulo Cabral de Vasconcellos, Vital Paulino CostaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
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Resumo: Objetivo: Avaliar a reprodutibilidade do teste de sobrecarga hídrica (TSH) em diferentes horários em que é realizado, em pacientes com glaucoma primário de ângulo aberto (GPAA) e em indivíduos normais. Métodos: Quinze pacientes com GPAA e 30 indivíduos normais foram submetidos a três TSHs, realizados em diferentes horários do dia (às 7:00, 12:00 e 17:00), em três dias diferentes. Foram comparados os resultados dos testes em pacientes com GPAA e indivíduos normais. Foram analisadas a concordância e a correlação entre os valores de medida basal, pico e variação de pressão intra-ocular (PIO) (pico de PIO - PIO basal) nos testes realizados nos diferentes horários. Apenas as medidas do olho direito foram analisadas. Resultados: Os valores médios de medida basal, pico e variação de PIO foram significativamente maiores nos pacientes glaucomatosos que nos indivíduos normais, em todos os horários (p<0,05). A análise de Bland-Altman apresentou limites de concordância de pico e variação de PIO maiores do que o clinicamente aceitável (> 3 mmHg), apesar de o teste de Pearson demonstrar boa correlação entre os resultados. Conclusões: O TSH apresenta valores de pico e variação de Pio significativamente maiores em pacientes glaucomatosos que em indivíduos normais. Os baixos níveis de concordância entre os TSHs realizados em diferentes horários do dia sugerem uma baixa reprodutibilidade do TSH, que pode limitar sua aplicabilidade para diagnóstico e acompanhamento do glaucoma
Abstract: Purpose: To evaluate the reproducibility of the water drinking test (WDT) performed at different times of the day, in primary open angle glaucoma (POAG) patients and normal individuals. Methods: Fifteen patients with POAG and 30 normal individuals underwent three WDTs at different times of the day (7 AM, 12 PM, and 5 PM) on 3 different days. Test results in POAG patients and normal individuals were compared. Agreement and correlation of intraocular pressure (IOP) baseline levels, peak levels, and IOP change (peak IOP - baseline IOP) on tests performed at different times were evaluated. Only right eye measurements were analyzed. Results: Mean baseline IOP, peak IOP and IOP change were significantly higher in POAG patients than in normal individuals, at all time intervals (p<0.05). The Bland-Altman analysis demonstrated limits of agreement for IOP peak levels and IOP changes larger than the clinically acceptable (> 3 mmHg), even though Pearson's test revealed good correlation among the results. Conclusions: The mean IOP peak and mean IOP change observed during the WDT are significantly higher in POAG patients than in control individuals. Low levels of agreement among WDTs performed at different times of the day suggest a poor reproducibility of WDT, which may limit its applicability for the diagnosis and follow-up of glaucoma
Mestrado
Oftalmologia
Mestre em Ciências Médicas
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Massa, Resende Graziela 1980. "Central corneal thickness and intraocular pressure in children undergoing congenital cataract surgery = a prospective, longitudinal study = Estudo longitudinal da paquimetria corneana central e da pressão intraocular de crianças submetidas à extração de catarata congênita." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/309868.
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Orientadores: Vital Paulino Costa, Carlos Eduardo Leite ArietaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: O presente estudo tem como objetivos investigar a variação da espessura corneana central (ECC) e da pressão intraocular (PIO) em crianças após cirurgia de catarata congênita, bem como fatores de risco associados com essas mudanças. Vinte e seis crianças com catarata congênita foram recrutadas prospectivamente antes da cirurgia para remoção da mesma. Trinta e sete olhos foram analisados. Todos pacientes foram submetidos a exame oftalmológico completo com avaliação da PIO e da ECC antes da cirurgia e 6, 12, 18, 24 e 36 meses após o procedimento cirúrgico, pelo mesmo observador. A paquimetria ultrassônica foi realizada com o aparelho Ocuscan RXP (Alcon Laboratories Inc, USA), e a tonometria foi realizada com o tonômetro de aplanação de Goldmann modelo R900 (Haag-Streit, Koeniz, Suíça) ou tonômetro de aplanação de Perkins (Clement Clark International ltd, Londres, Inglaterra). Dos 37 olhos, 15 tornaram-se afácicos e 22, pseudofácicos. A ECC média aumentou significativamente de 556,24 ± 44,19 ?m para 585,07 ± 56,45 ?m (p = 0,025) ao final de três anos, enquanto a PIO média aumentou significativamente de 12,05 ± 2,3 mmHg para 13,96 ± 2,99 mmHg (p = 0,005). Olhos afácicos foram submetidos à cirurgia em uma idade mais precoce (15,16 ± 32,02 meses) em comparação aos olhos pseudofácicos (71,48 ± 53,14 meses) (p <0,001). Após três anos, a média de variação da ECC, nos olhos afácicos (56,10 ± 46,97 ?m), foi significativamente maior que nos olhos pseudofácicos (12,71 ± 38,41 ?m) (p = 0,015). Encontramos correlação negativa entre a idade no momento da cirurgia e a variação da ECC (r = -0,34, p = 0,04), mas não entre idade e variação da PIO (r = -0,18, p = 0,27). Quando a cirurgia foi realizada entre 0 e 1 ano de idade, a média de variação da ECC, em três anos, foi de 69,0 ± 40,3 ?m, em comparação com 1,0 ± 23,17, -20,0 ± 8,04 e 34,25 ± 40,11 ?m quando as cirurgias foram realizadas de 1 a 5, 5 a 10 e > 10 anos, respectivamente (p <0,001). Não houve correlação da variação da PIO com a variação da ECC (r = 0,31, p = 0,06). Concluímos que a ECC aumenta nos olhos submetidos à cirurgia de catarata congênita, especialmente quando a cirurgia é realizada em uma idade precoce
Abstract: The present study aims to investigate the variation of central corneal thickness (CCT) and intraocular pressure (IOP) in children after congenital cataract surgery, as well as risk factors associated with these changes. Twenty-six children with congenital cataract were prospectively recruited prior to surgery. Thirty-seven eyes were analyzed. All patients underwent a complete ophthalmic examination with assessment of IOP and CCT before surgery and 6, 12, 18, 24 and 36 months after surgery by the same observer. Ultrasonic pachymetry was performed with the handset unit Ocuscan RXP (Alcon Laboratories Inc, USA) and tonometry was performed with the Goldmann applanation tonometer model R900 (Haag-Streit, Koeniz, Switzerland) or the Perkins applanation tonometer (Clement Clark International Ltd, London, England). Among the 37 eyes, 15 became aphakic and 22 pseudophakic. The mean CCT increased significantly from 556.24 ± 44.19 ?m to 585.07 ± 56.45 ?m (p = 0.025) at the end of three years, while the mean IOP increased significantly from 12.05 ± 2.3 mmHg to 13, 96 mmHg ± 2.99 (p = 0.005). Aphakic eyes underwent surgery at an earlier age (15.16 ± 32.02 months) compared with pseudophakic eyes (71.48 ± 53.14 months) (p <0.001). After three years, the mean CCT change in aphakic eyes (56.10 ± 46.97 ?m) was significantly higher than in pseudophakic eyes (12.71 ± 38.41 ?m) (p = 0.015). Age at the time of surgery was inversely correlated to CCT change (r = -0.34, p= 0.04), but not to IOP change (r=-0.18, p= 0.27). When surgery was performed between 0 and 1 year of age, the mean CCT change in 3 years was 69.0 ± 40.03 ?m, compared with 1.0 ± 23.17, -20.0 ± 6.56 and 34.25 ± 40.11 ?m when the surgeries were performed between 1-5, 5-10 and > 10 years, respectively (p <0.001). There was no correlation between IOP change and CCT change (r = 0.31, p = 0.06). We conclude that CCT increases in eyes undergoing congenital cataract surgery, especially when the surgery is performed at an early age
Doutorado
Oftalmologia
Doutora em Ciências Médicas
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Bassan, Fabiana Braunstein. "Avaliação da função endotelial em pacientes com hipertensão arterial resistente." Universidade do Estado do Rio de Janeiro, 2014. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=8530.
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Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de JaneiroA hipertensão arterial resistente (HAR) é definida pela persistência da pressão arterial (PA)≥140/90mmHg a despeito do uso de 3 anti-hipertensivos em doses plenas, incluindo diurético. Revisão recente da literatura mostra poucos estudos avaliando o perfil e o comportamento da função endotelial em pacientes com HAR. Objetiva avaliar a função endotelial em pacientes hipertensos resistentes. Estudo transversal com 60 pacientes que foram avaliados em uma visita (V3) de um estudo longitudinal, onde numa primeira fase todos pacientes tiveram padronização do tratamento anti-hipertensivo. Foram incluídos pacientes (V0) com PA>160/100mmHg e <220mmHg e todos receberam clortalidona 25mg/dia e enalapril 20mg 2x/dia ou losartana 50mg 2x/dia (intolerantes ao enalapril). Visita 1: se PA>140/90mmHg acrescentou-se anlodipino 5mg/dia, foi realizado avaliação laboratorial de rotina do hipertenso e monitorização ambulatorial da PA-24h (MAPA). Visita 2: se PA>140/90mmHganlodipino foi titulado para 10mg/dia. Visita 3: todos os pacientes receberam avaliação clínica, da pressão arterial por MAPA, laboratorial de rotina e da função endotelial. Formaram-se dois grupos: os que controlaram a PA, grupo hipertensão arterial controlada (HAC); e os que permaneceram com PA de consultório>140/90mmHg e PA na MAPA-24h>130/80mmHg, foram considerados resistentes. O grupo HAR recebeu aleatoriamente espironolactona ou clonidina por mais 12 semanas para tentar controlar a PA e o grupo HAC teve assistência farmacológica mantida no mesmo período. A PA foi avaliada por método oscilométrico com aparelho digital semi-automático Microlife modelo BP3AC1-1PC e MAPA por aparelho SpaceLabs 90207. A função endotelial avaliada através de tonometria arteriolar periférica (PAT) pelo Endo-PAT2000 e por biomarcadores (I-CAM-1, V-CAM-1, VEGF, MCP-1, IL-6, adiponectina) através da técnica LuminexTMxMAP. Dos 60 pacientes avaliados, 36 controlaram a PA, grupo HAC, e 24 permaneceram resistentes ao tratamento, grupo HAR, na visitaV3. Na avaliação da PA pela MAPA-24h observamos que no grupo HAC a PAS-24h foi de 121,1+1,7mmHg e no grupo HAR 147+3,3mmHg, enquanto a PAD-24h no grupo HAC foi de 76,64+1,5mmHg e no grupo HAR 88,58+2,4mmHg (p<0,0001). O descenso noturno, apesar de maior no grupo HAC, não apresentou significância estatística entre os dois grupos (p> 0,05). A função endotelial avaliada através do PAT mostrou índice de hiperemia reativa de 1,850,056 e 1,65+0,074 nos grupos HAC e HAR respectivamente (p= 0,036) e quando avaliada através dos biomarcadores observamos: ICAM-1 (HAC= 186,6+12,65 vs HAR= 240,9+23,76ng/ml, p= 0,038), VCAM-1 (HAC= 627,137,09vs HAR= 706,086,10ng/ml, p= 0,372),VEGF (HAC= 403,394,91 vs HAR= 612,788,27pg/ml, p= 0,123) e MCP-1 (HAC= 694,969,09 vs HAR= 787,052,80pg/ml, p= 0,315). Na avaliação dos biomarcadores inflamatórios, observamos IL-6 no grupo HAC= 1,8970,2165pg/mle no HAR= 9,7934,421pg/ml (p= 0,027) e adiponectina no grupo HAC= 105701516pg/ml e HAR= 84221295pg/ml (p=0,301). A razão de prevalência do comprometimento da função endotelial no grupo HAR foi de 54% (OR= 3,55; 95% IC 1,18- 10.67; p= 0,029). No presente trabalho, as análises das variáveis estudadas na visita V3, mostraram que os pacientes com HAR têm maior comprometimento da função endotelial que os pacientes com HAC.
Resistant hypertension (RH) is defined by the persistence of blood pressure (BP)≥140/90mmHg despite the use of 3 antihypertensive drugs at full doses, including a diuretic. Recent review of the literature shows few studies evaluating the profile and behavior of endothelial function in patients with RH. to evaluate endothelial function in resistant hypertensive patients. Cross-sectional study with 60 patients who were evaluated in a visit (V3) of a longitudinal study, where all patients initially had standardization of antihypertensive treatment. Patients with BP≥ 160/100mmHg and <220mmHg were included (V0) and they all received chlorthalidone 25mg/day and enalapril 20mg 2x/day or losartan 50mg 2x/day (intolerant enalapril). Visit 1: whether BP≥ 140/90mmHg amlodipine 5mg/day was added, it was conducted routine hypertensive laboratory evaluation and ambulatory monitoring of BP-24h (AMBP). Visit 2: if BP≥ 140/90mmHg amlodipine was titrated to 10mg/day. Visit 3: all patients received clinical evaluation, blood pressure by AMBP, routine laboratory and endothelial function. Two groups were formed: those who controlled the BP,group controlled hypertension (CH); and those who remained with BP≥ 140/90mmHg and BP on ABPM-24h≥ 130/80mmHg, were considered resistant. The RH group randomly received spironolactone or clonidine for 12 more weeks to try to control the BP and the CH group had pharmacological assistance maintained the same period. BP was measured by oscillometric method with semi-automatic digital device Microlife model BP3AC1-1PC and ABPM by SpaceLabs 90207 appliance. The endothelial function was valued through peripheral arteriolar tonometry (PAT) by Endo-PAT2000 and through biomarkers (I-CAM-1, V-CAM-1, VEGF, MCP-1, IL-6, adiponectin) by LuminexTMxMAP technique. Of the 60 patients evaluated, 36 controlled the BP, CH group, and 24 remained resistant to treatment, RH group in visit V3. In the assessment of BP by AMBP-24h was observed that in the CH group SBP-24h was 121.1+1.7 mmHg and RH group 147+3.3 mmHg, whereas DBP-24h in CH group was 76.64+1.5 mmHg and RH group 88.58+2.4 mmHg (p<0.0001). The nocturnal fall in BP, although higher in RH group, showed no statistical significance between the two groups (p> 0.05). Endothelial function assessed by the PAT showed reactive hyperemia index of 1.850.056 and 1.65+0.074 in CH and RH groups respectively (p = 0.036) and when evaluated by the biomarkers was observed: ICAM-1 (CH = 186.6+12.65ng/ml vs. RH= 240.9+23.76ng/ml, p= 0.038) VCAM-1 (CH= 627.137.09ng/ml vs. RH= 706.086.10ng/ml, p= 0.372), VEGF (CH= 403.394.91pg/ml vs.RH= 612.788.27pg/ml, p= 0.123) and MCP-1 (CH= 694.969.09pg/ml vs. RH=787.052.80pg/ml, p= 0.315). In the assessment of inflammatory biomarkers, was observed IL-6 in groups CH= 1.890.22pg/ml and RH= 9,794,41pg/ml (p= 0.027) and adiponectin in CH= 105701516pg/ml and RH= 1295 8422pg/ml (p= 0.301). The prevalence rate of impaired endothelial function in the RH group was 54% (OR = 3.55; 95% CI 1.18 - 10.67; p= 0.029). Conclusions: in this study, the analyzes of variables at visit V3, showed that patients with RH have greater impairment of endothelial function than patients with CH.
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Ghiggi, Eduardo. "Curva diária de pressão intraocular em porquinhos da índia (Cavia porcellus) de diferentes faixas etárias com tonometria de rebote." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/147658.
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A aferição da pressão intraocular (PIO) é essencial para o exame oftálmico. Objetivou-se estabelecer os valores da curva diária da PIO de porquinhos da índia de diferentes faixas etárias com tonômetro de rebote. A PIO foi aferida às 6, 12, 18 e 24 horas utilizando o tonômetro de rebote (Tonovet®). Os porquinhos da índia foram subdivididos em dois grupos com 10 animais no grupo I e 4 animais no grupo II, considerando as idades, designados por GI (animais entre 2 a 3 meses de idade) e GII (animais entre 2 a 3 anos de idade). Previamente, foram realizados teste da lágrima de Schirmer, prova da fluoresceína, biomicroscopia com lâmpada de fenda e oftalmoscopia indireta em todos animais. O valor médio da pressão intraocular foi de 12,0 ± 1,83 mmHg. Foram encontradas diferenças significativas entres as idades, sendo que os valores médios para o grupo I foram 11,63 ± 0,29 mmHg, e para o grupo II foram 12,82 ± 0,45mmHg (P= 0,0295). Não foram encontradas diferenças entre ambos os olhos (P= 0,7454). Não foram encontradas diferenças significativas nos valores da PIO relacionadas ao sexo (P= 0,1858). Os valores da PIO em porquinhos da índia tiveram alteração nas horas avaliadas. Com base nos resultados obtidos foi possível concluir que os valores da PIO em porquinhos da índia da sofrem alterações ao longo do dia. Os menores valores de pressão intraocular ocorreram às 18 horas.The measuring of intraocular pressure (IOP) it is essential for the ophthalmic evaluation; the aim of this study was establish the values of the IOP diurnal curve of guinea pigs with different ages using the rebound tonometer (Tonovet®). The animals were divided according to the age in two groups, Group I (GI) constituted with 10 guinea pigs aged between 2 -3 moths, and Group II (GII), 4 animals with 2 -3 years of old. Previously the Schirmer tear test, fluorescein test, biomicroscopy with slit lamp, and direct optalmoscopy were performed on all animals. The men value of IOP was 12.0±0.34 mmHg. Statistical difference were found between ages (mean GI 11.64 ± 0.29 mmHg, and GII 12.83 ± 0.45mmHg), did not have statistical difference related with gender (P= 0.1858) or between eyes (P= 0.7454). In conclusion the guinea pigs had alteration of IOP true the day, the values of IOP are higher in the morning period, decrease true the day and at the night period haves an elevation again.
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Pillai, Aditi. "Effects of Body Temperature and General Anesthetics on Intraocular Pressure in Rats." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7351.
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Ocular hypertension has been identified as the fundamental risk factor in glaucoma which is the leading cause for irreversible blindness in the world. Understanding the different factors that affect IOP is of utmost importance in clinical management as IOP is considered as the fundamental factor in assessing the efficiency of glaucoma medications. Several studies have attempted to assess factors that could affect IOP including age, body position, blood pressure, anesthetics commonly used during eye operations, etc. However, in most of these studies IOP is measured under anesthesia using rodent models and these anesthetics could affect the IOP measurements directly or indirectly. The use of tonometry in such experiments also includes certain limitations like acquiring IOP at discrete moments in time, human error while handling the instrument and stress induced spikes in IOP while handling awake animals. This study uses a wireless continuously monitoring device to eliminate these limitations while also acquiring IOP at a higher rate.
Anesthesia induction is known to lower body temperature. However, previous studies on the effects of various anesthetic agents fail to take into account this drop in body temperature which could potentially lead to erroneous results. This thesis focuses on studying the effects of two commonly used anesthetic agents, isoflurane and ketamine while accounting for loss in body temperature. The effects of changing body temperature on intraocular pressure was also studied to help understand the effects of these factors accurately. There was a statistically significant drop (p<0.001) in intraocular pressure post isoflurane induction with no heat support across several animals. The addition of heat support in the next set of experiments resulted in an almost steady pressure throughout the experiment. Since the body temperature was maintained constant throughout the experiment, there was no statistically significant difference (p>0.05) among IOP’s for the awake and anesthetized condition. This conclusion was then confirmed by obtaining a direct effect of changing body temperature on IOP. There was a rise in IOP while the animal was placed on a 42 degree Celsius heating pad and a drop in IOP while the animal was placed on a 20 degree Celsius surface with no heat support. The corresponding changes in body temperature were confirmed using a rectal thermometer. There were no significant changes in the IOP measured by the sensor while measuring pressure with the iCare tonolab. Applanation tonometry however produced an average mean intraocular pressure increase of 2.11 ± 1.62 mmHg.
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Jóhannesson, Gauti. "Intraocular pressure : clinical aspects and new measurement methods." Doctoral thesis, Umeå universitet, Oftalmiatrik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-40383.
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Intraocular pressure (IOP) measurement is a routine procedure and a fundament in glaucoma care. Elevated IOP is the main risk factor for glaucoma, and to date, reduction of IOP is the only possible treatment. In a retrospective clinical material, the prevalence of open angle glaucoma was estimated on the west coast of Iceland. IOP measurement and optic nerve head examination were used to capture glaucoma suspects, within the compulsory ophthalmological examination for the prescription of eye glasses. The results were mainly in agreement with a recent prospective study in the same region. This indicated that retrospective data, under certain conditions, may contribute with useful information on the prevalence of glaucoma. However, normal tension glaucoma is underestimated if perimetry and/or fundus photography are not included in the examination. Three studies focused on the measurement of IOP. Goldmann applanation tonometry (GAT) is the standard method. GAT is affected by corneal properties, e.g. central corneal thickness (CCT) and corneal curvature (CC). Refractive surgery changes these properties. This has put focus on how corneal biomechanics translate into tonometric errors and stimulated the development of new methods. As a result, Pascal ® Dynamic Contour Tonometry (PDCT) and Icare® rebound tonometry have been introduced. A method under development by our research group is Applanation Resonance Tonometry (ART). It is based on resonance technology and estimates IOP from continuous measurement of force and contact area. Comparison of PDCT, Icare and GAT in a prospective study showed that the concordance to GAT was close to the limits set by the International Standard Organization (ISO) for PDCT, while Icare was outside the limits. To investigate if laser-assisted subepithelial keratectomy (LASEK) affects tonometry, a study was performed where measurements with GAT, PDCT and ART were obtained before, three and six months after LASEK. The hypothesis was that PDCT and ART would be less affected by LASEK than GAT. The results showed a statistically significant reduction of measured IOP three and six months after LASEK for all tonometry methods. Change in visual acuity and IOP between three and six months suggested a prolonged postoperative process. A servo-controlled prototype (ART servo) was developed. A study was undertaken to assess the agreement of ARTservo and a further developed v manual prototype (ART manual) with GAT. The study design was in accordance with the requirements of the ISO standard for tonometers. ARTmanual fulfilled the precision requirements of the ISO standard. ARTservo did not meet all the requirements of the standard at the highest pressure levels. Four tonometry methods, GAT, PDCT, Icare and ART, were investigated. None of them was independent of both CCT and CC. The inconsistencies in the results emphasize the importance of study design. A meta-analysis comprising healthy eyes (IOP ≤ 21 mmHg) in the three papers, revealed age as an important confounder. In summary, glaucoma prevalence in Iceland was investigated and the results indicated that a retrospective approach can contribute with meaningful information. ART and PDCT had a similar agreement to GAT. ART manual fulfilled the precision requirements set by the ISO-standard, ARTservo and PDCT were close, while Icare was distinctly outside the limits. All tonometry methods were affected by LASEK and no method was completely independent of corneal properties.
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Polyvas, Peter Pal. "Development And Evaluation Of A Multi-Force Sensor Based Trans-Palpebral Tactile Tonometer." Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/338901.
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Glaucoma is a group of diseases that lead to a progressive loss of vision in the majority of the cases due to elevated intraocular pressure (IOP). Glaucoma is the second leading cause of blindness after cataract. According to the National Eye Institute's report, there were almost 2.7 million detected cases in the United States in 2010.Everybody older than 40, African Americans and Hispanics at any age, are at high risk and would need frequent IOP measurement in order to diagnose the disease at an early stage. Majority of the existing tonometers measure the IOP through the cornea and their operation requires clinical professionals. As a result, the measurement has to take place at the doctor's office and requires local anesthesia. This work demonstrates a novel multi-probe tactile-tonometer, which is operated by the patients and measures the IOP through their eyelid. Finite element (FE) models were used to estimate the static, mechanical response of the eye, due to indentation at different IOPs. The models include hyperelastic behavior of the sclera and cornea. The thickness variation of the sclera, throughout the geometry was also considered. Volumetric constraint was applied on the eye cavity, but its actual anatomic structure was neglected. In-vitro indentation tests were performed on enucleated porcine eyeballs, as a proof of concept of tactile-tonometry. Eye/patient specific calibration method was demonstrated, in order to further improve accuracy ("Forward Biomechanics"), and in-vivo estimation of biomechanical properties of the eye ("Inverse Biomechanics"). The method uses simplified FE models and a feed forward artificial neural network (ANN). The tactile-tonometer was implemented for human use, and clinical studies were performed on a small number (10) of human subjects. Based on the measurements from the recruited 10 patients (3 females, 7 males) with a mean age ±SD of 43±19.33 and the measured IOP range of 9.25-21.25mmHg, the novel technique has a mean of differences of ≈ 0mmHg and its 95% limits of agreement are ±4.84mmHg with respect to the Goldmann Applanation Tonometer.
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Lindenmeyer, Rodrigo Leivas. "Pressão intra-ocular em pré-termos de muito baixo peso de nascimento e sua relação com a idade pós-concepção." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/61888.
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Objetivo: medir a pressão intra-ocular (PIO) em pré-termos de muito baixo peso (PMBP) e correlacionar com a idade pós-concepção (IPC). Métodos: Estudo longitudinal incluindo 50 pré-termos. Local: Hospital de Clínicas de Porto Alegre. Período: entre novembro de 2008 e junho de 2010. Pacientes: PMBP definido como idade nascimento ≤ 1.500 g e idade gestacional ≤ 32 semanas. Intervenção: medidas semanais da PIO. Principais desfechos: variação da PIO de acordo com a idade pós-concepção (IPC definida como a idade gestacional ao nascimento mais a idade no momento do exame) nas semanas seguintes ao nascimento pré-termo. Análise estatística: modelos de efeitos mistos foram utilizados para determinar a variação da PIO em relação a IPC. Foram calculados as médias e os percentis 10 e 90 (P10 e P90) para os valores da PIO. Resultados: Cinqüenta PMBP com idade gestacional média de 29,7 ± 1,6 semanas e peso de nascimento de 1.127,7 ± 222,7 gramas foram avaliados. Não houve diferença significativa entre a PIO do olho direito e do olho esquerdo (p=0.177). A média da PIO em toda a coorte, considerando ambos os olhos, foi de 14,9 ± 4,5 mmHg, sendo que 13,5% das medidas isoladas da PIO foram superiores a 20 mmHg. A PIO reduziu em média 0,29 mmHg para cada aumento de uma semana da IPC (p=0.047 IC95%: -0,58 a -0,0035). A PIO média (P10-P90) reduziu de 16,3 mmHg (10,52-22,16) com 26,3 semanas de IPC para 13,1 mmHg (7,28-18,92) com 37,6 semanas de IPC. Conclusões: A PIO média em PMBP foi 14,9 ± 4,5 mmHg e apresentou correlação negativa em relação a idade pós-concepção.Purpose: To measure intraocular pressure (IOP) in very low birth weight preterm infants and correlate it with the postconceptional age (PCA). Methods: Longitudinal study including 50 premature infants. Setting: Hospital de Clinicas de Porto Alegre, Brazil. Patients: Very low birth weight premature infants (defined as birth weight ≤1,500 g and gestational age ≤32 weeks). Intervention: Weekly measurements of the IOP. Main outcomes: The variation of IOP according to the postconceptional age (PCA defined as the gestational age at birth plus the age in weeks at the time of examination) in the weeks following preterm birth. Statistics: Mixed-effects models were used for the statistical analysis to determine IOP variation according to PCA. Means, 10th and 90th percentiles were calculated for IOP values. Results: Fifty preterm infants with a mean gestational age of 29.7 ± 1.6 weeks and mean birth weight of 1,127.7 ± 222.7 grams were evaluated. Mean IOP in the whole cohort considering both eyes was 14.9 ± 4.5 mmHg, and 13.5% of the IOP measurement values were greater than 20 mmHg. The analysis revealed a mean IOP reduction of 0.29 mmHg for each increase of PCA (p=0.047; 95% CI, -0.58 to -0.0035). Mean IOP (P10- P90) decreased from 16.3 mmHg (10.52-22.16) at 26.3 weeks PCA to 13.1 mmHg (7.28- 18.92) at 37.6 weeks PCA. Conclusions: Mean IOP in very low birth weight preterm infants was 14.9 ± 4.5 mmHg and was negatively correlated with PCA.
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Reuter, Anne. "Evaluation des Rebound-Tonometers TonoVet für die Bestimmung des Augeninnendrucks bei Greifvögeln und Eulen." Berlin mbv, 2009. http://d-nb.info/1000280578/04.
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Azuma, Masanori. "Association Between Endothelial Function (Assessed on Reactive Hyperemia Peripheral Arterial Tonometry) and Obstructive Sleep Apnea, Visceral Fat Accumulation, and Serum Adiponectin." Kyoto University, 2016. http://hdl.handle.net/2433/204577.
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Pinto, Jenifer Palma dEl-Rei. "O efeito agudo do chocolate amargo sob a função endotelial é dependente da idade em hipertensos com baixo risco cardiovascular." Universidade do Estado do Rio de Janeiro, 2011. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=5923.
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Dados recentes indicam uma relação inversa entre doença cardiovascular e consumo de flavonóides. O objetivo do estudo foi identificar parâmetros clínicos e vasculares de pacientes hipertensos tratados que apresentaram efeitos benéficos na função vascular após o consumo de chocolate amargo com 70% de cacau por sete dias. Vinte e um pacientes hipertensos em tratamento medicamentoso, ambos os sexos, com idades entre 40-65 anos, foram incluídos em um ensaio clínico intervencional com aferição de pressão arterial, dilatação mediada por fluxo braquial (DMF), tonometria arterial periférica (EndoPAT) e parâmetros hemodinâmicos centrais pelo SphygmoCor. Após sete dias de consumo de chocolate amargo (70% cacau) 75g/dia, as avaliações clínica e vascular foram repetidas. Os pacientes foram divididos em dois grupos de acordo com a resposta da DMF em respondedores (que apresentaram melhora na DMF, n= 12) e não-respondedores (que não apresentaram melhora, n = 9). O grupo respondedor apresentou menor média de idade (54 7 vs 61 6 anos, p = 0,037) e menor risco cardiovascular pelo escore de Framingham (2,5 1,8 vs 8,1 5,1%, p = 0,017). Além disso, os pacientes respondedores apresentaram valores mais baixos de pressão de pulso tanto periférica (55 9 vs 63 5 mmHg, p = 0,041), quanto central (44 10 vs 54 6, p = 0,021) quando comparado ao grupo não respondedor. A resposta da DMF apresentou correlação moderada e negativa com o escore de Framingham (r = -0,60, p = 0,014), com a DMF basal (r = 0,54, p = 0,011), com o índice de hiperemia reativa basal (IHR) obtido pelo EndoPAT (r = -0,56, p = 0,008) e com a pressão de pulso central (r = -0,43, p = 0,05). No entanto, após análise de regressão linear, apenas o escore de Framingham e o IHR basal foram associados com a resposta da DMF. Em conclusão, nesta amostra de pacientes hipertensos tratados, os indivíduos que apresentaram melhora da função endotelial com o consumo de chocolate amargo com 70% de cacau também mostraram redução da pressão arterial tanto sistólica como diastólica, eram mais jovens e tinham menor pressão de pulso e menor risco cardiovascular, apesar de uma disfunção endotelial basalRecent findings indicate an inverse relationship between cardiovascular disease and consumption of flavonoids. We aimed to identify clinical and vascular parameters of treated hypertensive patients who present beneficial effects of dark chocolate on vascular function. Twenty-one hypertensive patients in drug therapy, both genders, aged 40-65 years, were included in a prospective study with measurement of blood pressure, brachial flow-mediated dilatation (FMD), peripheral arterial tonometry (EndoPAT) and central hemodynamic parameters by SphygmoCor. After seven days of eating dark chocolate (70% cocoa) 75g/day, the clinical and vascular evaluation were repeated. Patients were divided into two groups according to the response in FMD: responders (increase in FMD, n=12) and non-responders (no improvement in FMD, n=9). The responder group had a lower mean age (547 vs 616 years, p=0.037) and cardiovascular risk by Framingham score (2.51.8 vs 8.15.1 %, p=0.017). Moreover, responders patients presented lower values of both peripheral (559 vs 635 mmHg, p=0.041), and central pulse pressure (4410 vs 546, p=0.021) than those in non-responder group. The FMD response showed moderate and negative correlation with Framingham score (r= -0.60, p=0.014), with baseline FMD (r= 0.54, p=0.011), baseline reactive hyperemia index (RHI) by EndoPAT (r= -0.56, p=0.008) and central pulse pressure (r= -0.43, p=0.05). However, after linear regression analysis, only the Framingham score and baseline RHI were associated with FMD response. In conclusion, this sample of treated hypertensive patients, individuals who showed improvement in endothelial function with the consumption of dark chocolate with 70% cocoa also showed reduction in both systolic and diastolic blood pressure, were younger and had lower pulse pressure and lower cardiovascular risk, although a basal endothelial dysfunction
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Barros, João Maximiano Pierin de [UNESP]. "Efeitos na expansão volêmica e na oxigenação sistêmica e gastrointestinal após reposição com hidroxietilamido, associado ou não à solução salina hipertônica, e Ringer lactato em cães submetidos a choque hemorrágico." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/106001.
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As variáveis hemodinâmicas e de oxigenação sistêmica não refletem com precisão a hipoperfusão esplâncnica durante o choque hipovolêmico, dificultando o tratamento adequado. A expansão volêmica após a reposição fluídica é fundamental para promover a oxigenação sistêmica e regional após o choque hemorrágico. Em contraste com as soluções convencionais de reposição volêmica, a menor expansão plasmática proporcionada pela administração de hidroxietilamido em solução hipertônica de cloreto de sódio, durante o choque hemorrágico, poderia determinar uma menor oferta de oxigênio sistêmico, com prejuízo à oxigenação gástrica. O estudo teve como objetivo comparar a expansão volêmica e os efeitos imediatos na oxigenação sistêmica e da mucosa gástrica após a administração de hidroxietilamido a 6% (peso molecular de 130 kDa, grau de substituição de 0,4) em solução hipertônica de cloreto de sódio a 7,5% (HHEA), Ringer lactato (RL) e hidroxietilamido a 6% (130/0,4) em cloreto de sódio a 0,9% (HEA), em cães submetidos à choque hemorrágico. Trinta cães, sem raça definida, sob anestesia e esplenectomizados, foram submetidos a sangramento (30 ml/kg) visando manter a pressão arterial média de 40 a 50 mm Hg durante 45 9 Introdução e Literatura minutos, sendo feita a reposição volêmica após este período com RL (n=10), na razão de 3:1 para o sangue removido; HEA (n=10), na razão de 1:1 para o sangue removido; e HHEA (n=10), 4 ml/kg. A expansão do volume intravascular (através da diluição do azul de Evans e da hemoglobina), e os atributos hemodinâmicos, e de oxigenação sistêmica e gástrica (através da tonometria gástrica), foram determinados no momento basal, após 45 minutos de hemorragia, e aos 5, 45 e 90 minutos após a reposição volêmica. A solução de HHEA aumentou o volume sanguíneo, devido à alta eficiência na...
Hemodynamic and global oxygen transport variables have failed to reflect splanchnic hypoperfusion, resulting in a failure to recognize inadequately treated hemorrhagic shock. Volemic expansion after fluid resuscitation is essential to improve global and regional oxygen in hemorrhagic shock. We hypothesized that, in contrast with conventional plasma expanders, the smaller volemic expansion from hypertonic hydroxyethyl starch solution administration in hemorrhagic shock may determine lesser systemic oxygen delivery and gastric oxygenation. We used hemorrhaged dogs to compare the early intravascular volume expansion and systemic and gastric oxygenation effects of 7.5% NaCl 6% hydroxyethyl starch 130/0.4 (HHES), lactated Ringer’s (LR), and 0.9% NaCl 6% hydroxyethyl starch (HES) solutions. Thirty mongrel dogs anesthetized and submitted to splenectomy, were bled (30mL/kg) to hold mean arterial pressure at 40-50 mm Hg over 45 minutes and were randomly resuscitated in three groups: LR (n=10) at 3:1 ratio to shed blood; HES (n=10) at 1:1 to shed blood; and HHES (n=10), 4mL/kg. Intravascular volume expansion (Evans blue and hemoglobin dilution), hemodynamic, systemic oxygenation and gastric intramucosal- arterial PCO2 gradient (PCO2 gap) variables were measured at baseline, after 45 min of hemorrhage, and 5, 45, and 90 min after fluid resuscitation. HHES increased blood volume, due to the 11 Introdução e Literatura high volume expansion efficiency, but intravascular volume expansion with this solution was the smallest of the solutions. All three solutions induced a similar hemodynamic performance but HHES showed lower mixed venous oxygen saturation and higher systemic oxygenation extraction and PCO2 gap than LR and HES. In conclusion, the smaller volume state from HHES after resuscitation provides worse systemic and gastric oxygenation recovery compared to LR and HES in dogs submitted... (Complete abstract click electronic access below)
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Marchan, Pedro Rafael Apulcro Correa. "TONOMETRIA E ECOBIOMETRIA OCULAR EM TUCANO-TOCO (Ramphastos toco) E TUCANO-DE-BICO-VERDE (Ramphastos dicolorus)." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/4136.
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The eyesight of birds is essential for their survival in a free environment; tiny alteration in this organ may cause loss of vision, consequently the difficulty or even the impossibility to hunt, move or protect themselves from predators; due to these particularities, the objective of this paper was to know the normal rate of intra-ocular pressure (IOP) and to identify the ocular anatomy through sonographic biometry in B-scan through transpalpebral way, so the ophthalmic examination can be complete and reliable. It was valued the IOP of 15 Toco Toucans (Ramphatos toco) and 15 Red-breasted Toucan (Ramphastos dicolorus) through applanation tonometry, using a Tono-Pen VET® tonometer and executed sonographic biometry ocular in 5 Toucans Toco and in 5 Red-breasted Toucan. The IOP from Toco Toucans, reliable in 95% got the media between 13,79 mmHg to17,61 mmHg, while the Red-breasted Toucan got the IOP between 12,05 mmHg and 16,81 mmHg. The ocular ultrasound eye was efficient as it could identify the previous segment, the lens, the posterior segment, positioning of the retina, Pecten and retrobulbar space. The Toco Toucans sonographic biometry obtained the bulbar average axial length of 1,66 cm, axial shaft of anterior segment 0,25 cm, shaft axial lens 0,35 cm axial shaft of posterior segment 1,05 cm, transverse shaft of the posterior segment 2,20 cm, transverse shaft of the lens 1,21 cm, and in Red-breasted Toucan the bulbar average axial length of 1,29 cm, axial shaft of anterior segment 0,10 cm, axial shaft lens 0,40 cm axial shaft of posterior segment 0,79 cm, shaft transverse of the posterior segment 1,39 cm, shaft transverse of the lens 0,99 cm. It follows that it is possible to measure IOP by tonometry with Tono-pen VET® tonometer and ocular sonographic biometry the B-scan transpalpebral, route is feasible for these species.A visão das aves é fundamental para a sua sobrevivência em vida livre, pequenas alterações neste órgão, podem levar a perda da acuidade visual, consequentemente dificuldade ou mesmo impossibilidade em caçar, se locomover ou se defender de predadores. Devido a estas particularidades, o objetivo deste trabalho foi o de conhecer o valor normal da pressão intraocular (PIO) e identificar a anatomia ocular por meio da ecobiometria em modo B pela via transpalpebral, tornando o exame oftálmico mais completo e fidedigno. Foi avaliada a PIO de 15 Tucanos-toco (Ramphastos toco) e de 15 Tucanos-de-bico-verde (Ramphastos dicolorus) por meio da tonometria de aplanação, usando o tonômetro Tono-Pen VET®. Foi realizado ecobiometria ocular em 5 Tucanos-toco e 5 Tucanos-de-bico-verde. A PIO dos Tucanos-toco com 95% de confiança teve uma média entre 13,79 mmHg e 17,61 mmHg, já os Tucanos-de-bico-verde tiveram a PIO entre 12,05 mmHg e 16,81 mmHg. A ecografia ocular se mostrou eficiente pois foram identificados o segmento anterior, a lente, o segmento posterior, o posicionamento da retina, o pécten e o espaço retrobulbar. Na ecobiometria foram obtidos nos Tucanos-toco média do eixo axial bulbar de 1,66 cm, eixo axial do segmento anterior 0,25 cm, eixo axial do segmento posterior 1,05 cm, eixo transversal do segmento posterior 2,20 cm, eixo axial da lente 0,35 cm e eixo transversal da lente 1,21 cm, e nos Tucanos-de-bico-verde a média do eixo axial bulbar de 1,29 cm, eixo axial do segmento anterior 0,10 cm, eixo axial do segmento posterior 0,79 cm, eixo transversal do segmento posterior 1,39 cm, eixo axial da lente 0,40 cm e eixo transversal da lente 0,99 cm. Conclui-se que é possível mensurar a PIO por meio da tonometria de aplanação com o tonômetro Tono-pen VET® e que a ecobiometria ocular, em modo B pela via transpalpebral é viável para estas espécies.
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Contrin, Ligia Marcia. "A tirosina como marcador de lesão intestinal na isquemia mesentérica." Faculdade de Medicina de São José do Rio Preto, 2005. http://bdtd.famerp.br/handle/tede/207.
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Previous issue date: 2005-12-19Introduction: The intestinal tract plays a central role in the protein catabolic response after infection or injury. Tyrosine (an index of overall proteolysis) and the release of lactate in intestinal luminal perfusate (ILP) during ligation of the superior mesenteric artery (SMA) were assessed. The present study aims to determine whether tyrosine flow from intracellular compartment to lumen could occur during ischemia induced-gut injury. Methods: Fourteen New-Zealand rabbits were allocated into 2 groups (group I: control (n=6) and group II: ischemia (n=8). SMA (QSMA) and aortic (Qaorta) flows were measured using ultrasonic flow probes. A segment from the ileum was isolated using two multilumen tubes with inflated balloons to delimit a closed segment to be perfused. In a second gut segment, a tonometric catheter (TRIP® Tonometry Catheter, Datex, Finland) was placed. Animals in group II were submitted to ligation of SMA after baseline measurements. The concentrations of tyrosine and lactate in intestinal lumen of both serum and perfusate were determined. Tyrosine was assayed by the fluorometric method as previously described. (1) Results: The lactate concentrations significantly increased in ILP after the ligation of SMA in 4 hours (from de 0.1 ± 0.7 mEq/L to 3.3 ± 1.6 mEq/L in 2 hours) compared to control group (from 0.1 ± 0.5 mEq/L para 0.3 ± 0.1 mEq/L in 2 hours) (p<0.05). Luminal tyrosine significantly increased during ischemia compared to control group in 2 hours (from 10.1 ± 7.7 mM/mL to 93 ± 63 mM/mL, group II; from 9.9 ± 7.8 mM/mL to 25.6 ± 24.0 mM/mL, group I, p<0.05). Conclusion: Tyrosine flow from intracellular compartment to lumen xiii occurred in this model suggesting ischemia-gut-derived proteolysis and a potential role for tyrosine as a marker of cell injury.
O trato gastrintestinal exerce um papel central na resposta catabólica da proteína após lesão ou infecção. Avaliaram-se a tirosina (um índice de proteólise global) e a liberação de lactato no perfusado do lúmen intestinal durante a ligação da artéria mesentérica superior (AMS). O objetivo deste estudo é determinar se o fluxo de tirosina proveniente do compartimento intracelular para o lúmen poderia ocorrer durante lesão do intestino induzida por isquemia. Métodos: Catorze coelhos da raça New-Zealand foram divididos em dois grupos (grupo I: controle, n=6 e grupo II: isquemia, n=8). Os fluxos da artéria mesentérica superior (QSMA) e da aorta (Qaorta) foram mensurados usando sondas de fluxo ultra-sônicas. Isolou-se, para realizar a perfusão, um segmento do íleo usando dois cateteres multilumen com balões inflados para delimitar um segmento fechado. Em um segundo segmento intestinal, colocou-se um cateter de tonometria (TRIP® Tonometry Catheter, Datex, Finland). Submeteram-se os animais no grupo II à ligação da AMS após mensurações iniciais. Determinaram-se as concentrações de lactato e tirosina no soro e no perfusado do lúmen intestinal (PLI). Analisou-se a Tirosina pelo método de fluorometria como descrito anteriormente. (1) Resultados: As concentrações de lactato aumentaram significativamente no PLI após ligação da AMS em 4 horas no grupo II (de 0,1 ± 0,7 mEq/l para 3,3 ± 1,6 mEq/l em 2 horas) em comparação com o controle (de 0,1 ± 0,5 mEq/l para 0,3 ± 0,1 mEq/l em 2 horas) (p<0,05). A tirosina no lúmen aumentou significativamente durante a isquemia em comparação com o controle em 2 horas (de 10,1 ± 7,7 mM/ml para 93 ± 63 mM/ml, grupo II; de 9,9 ± 7,8 mM/ml para 25,6 ± 24,0 mM/ml, grupo I, p<0,05). Conclusão: O fluxo da tirosina proveniente do compartimento intracelular para o lúmen ocorreu nesse modelo, sugerindo uma proteólise induzida pela isquemia intestinal, e um potencial papel para a tirosina como um marcador da lesão celular.
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Barros, João Maximiano Pierin de. "Efeitos na expansão volêmica e na oxigenação sistêmica e gastrointestinal após reposição com hidroxietilamido, associado ou não à solução salina hipertônica, e Ringer lactato em cães submetidos a choque hemorrágico /." Botucatu : [s.n.], 2009. http://hdl.handle.net/11449/106001.
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Orientador: José Reinaldo Cerqueira BrazBanca: Luiz Antonio Vane
Banca: Jorge João Abrão
Banca: Luiz Marcelo Sá Malbonisson
Banca: Rosa Inês Costa Pereira
Resumo: As variáveis hemodinâmicas e de oxigenação sistêmica não refletem com precisão a hipoperfusão esplâncnica durante o choque hipovolêmico, dificultando o tratamento adequado. A expansão volêmica após a reposição fluídica é fundamental para promover a oxigenação sistêmica e regional após o choque hemorrágico. Em contraste com as soluções convencionais de reposição volêmica, a menor expansão plasmática proporcionada pela administração de hidroxietilamido em solução hipertônica de cloreto de sódio, durante o choque hemorrágico, poderia determinar uma menor oferta de oxigênio sistêmico, com prejuízo à oxigenação gástrica. O estudo teve como objetivo comparar a expansão volêmica e os efeitos imediatos na oxigenação sistêmica e da mucosa gástrica após a administração de hidroxietilamido a 6% (peso molecular de 130 kDa, grau de substituição de 0,4) em solução hipertônica de cloreto de sódio a 7,5% (HHEA), Ringer lactato (RL) e hidroxietilamido a 6% (130/0,4) em cloreto de sódio a 0,9% (HEA), em cães submetidos à choque hemorrágico. Trinta cães, sem raça definida, sob anestesia e esplenectomizados, foram submetidos a sangramento (30 ml/kg) visando manter a pressão arterial média de 40 a 50 mm Hg durante 45 9 Introdução e Literatura minutos, sendo feita a reposição volêmica após este período com RL (n=10), na razão de 3:1 para o sangue removido; HEA (n=10), na razão de 1:1 para o sangue removido; e HHEA (n=10), 4 ml/kg. A expansão do volume intravascular (através da diluição do azul de Evans e da hemoglobina), e os atributos hemodinâmicos, e de oxigenação sistêmica e gástrica (através da tonometria gástrica), foram determinados no momento basal, após 45 minutos de hemorragia, e aos 5, 45 e 90 minutos após a reposição volêmica. A solução de HHEA aumentou o volume sanguíneo, devido à alta eficiência na... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Hemodynamic and global oxygen transport variables have failed to reflect splanchnic hypoperfusion, resulting in a failure to recognize inadequately treated hemorrhagic shock. Volemic expansion after fluid resuscitation is essential to improve global and regional oxygen in hemorrhagic shock. We hypothesized that, in contrast with conventional plasma expanders, the smaller volemic expansion from hypertonic hydroxyethyl starch solution administration in hemorrhagic shock may determine lesser systemic oxygen delivery and gastric oxygenation. We used hemorrhaged dogs to compare the early intravascular volume expansion and systemic and gastric oxygenation effects of 7.5% NaCl 6% hydroxyethyl starch 130/0.4 (HHES), lactated Ringer's (LR), and 0.9% NaCl 6% hydroxyethyl starch (HES) solutions. Thirty mongrel dogs anesthetized and submitted to splenectomy, were bled (30mL/kg) to hold mean arterial pressure at 40-50 mm Hg over 45 minutes and were randomly resuscitated in three groups: LR (n=10) at 3:1 ratio to shed blood; HES (n=10) at 1:1 to shed blood; and HHES (n=10), 4mL/kg. Intravascular volume expansion (Evans blue and hemoglobin dilution), hemodynamic, systemic oxygenation and gastric intramucosal- arterial PCO2 gradient (PCO2 gap) variables were measured at baseline, after 45 min of hemorrhage, and 5, 45, and 90 min after fluid resuscitation. HHES increased blood volume, due to the 11 Introdução e Literatura high volume expansion efficiency, but intravascular volume expansion with this solution was the smallest of the solutions. All three solutions induced a similar hemodynamic performance but HHES showed lower mixed venous oxygen saturation and higher systemic oxygenation extraction and PCO2 gap than LR and HES. In conclusion, the smaller volume state from HHES after resuscitation provides worse systemic and gastric oxygenation recovery compared to LR and HES in dogs submitted... (Complete abstract click electronic access below)
Doutor
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Mendes, Marcio Henrique. "Comparação dos valores da pressão intraocular obtidos com diferentes tonômetros e suas correlações com dados biométricos oculares no glaucoma congênito." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/5/5149/tde-16012014-154728/.
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OBJETIVOS: Comparar os valores da pressão intraocular (PIO), obtidos por intermédio do tonômetro de Perkins (TPK), tonômetro de contorno dinâmico Pascal (TCD) e Tono-Pen (TNP), confrontando-os com o tonômetro de aplanação de Goldmann (TAG), e correlacionar seus valores tonométricos com parâmetros biométricos oculares em pacientes portadores de glaucoma congênito primário. MÉTODOS: Estudo prospectivo, transversal, com inclusão de 46 pacientes (46 olhos) com diagnóstico de glaucoma congênito primário, com idades entre 12 e 40 anos, após obtenção do Termo de Consentimento Livre e Esclarecido. Todos os olhos estudados foram submetidos à tonometria ocular usando os tonômetros de Goldmann, de Perkins, o Tono-Pen e o tonômetro de contorno dinâmico Pascal. A ordem das tonometrias foi aleatória e o tonômetro de Goldmann foi adotado como padrão ouro. Os parâmetros biométricos estudados foram a curvatura (medida pela ceratometria), a espessura central da córnea (paquimetria), o diâmetro corneal (medido por meio de compasso cirúrgico) e o comprimento axial do olho foi obtido pela biometria ultrassônica. As distribuições dos parâmetros biométricos, assim como das tonometrias foram plotadas e analisadas conforme teste de Kolmogorov-Smirnov para aceitação de normalidade. O teste t de Student pareado para amostras independentes foi empregado para comparar as médias tonométricas de cada tonômetro com o padrão ouro. As correlações entre os parâmetros biométricos e as tonometrias foram realizadas através do coeficiente de correlação de Pearson e gráficos de regressão linear. O mesmo procedimento foi feito entre os parâmetros biométricos e as diferenças entre as três distintas tonometrias e a TAG. A concordância entre os tonômetros Perkins, Pascal e Tono-Pen e o de Goldamnn foi realizada pelo teste de concordância de correlação (CCC) e graficamente pelo método de Bland-Altman. O valor de corte de 2 mmHg foi adotado para avaliar a empregabilidade clínica desses tonômetros em pacientes semelhantes aos da amostra. RESULTADOS: O teste de Kolmogorov-Smirnov indicou aceitação da normalidade para todas as distribuições estudadas (TAG, TPK, TCD, TNP, Diâmetros corneal e axial, ceratometria média e paquimetria). Os momentos de correlação de Pearson empregados para realizar estudo das correlações entre os parâmetros biométricos e cada tonometria foram estatisticamente não significativos. As correlações entre os parâmetros biométricos e as diferenças entre tonometrias em relação ao TAG não apresentaram significância em sua maioria, sendo a única exceção a correlação moderada entre a diferença do TAG e o Tono-Pen versus a ceratometria média. No entanto, o coeficiente de determinação evidenciou influência modesta da ceratometria nessas diferenças (r² = 0,16; p = 0,004). O teste t de Student pareado demonstrou diferença significativa entre o TAG e o TP (p < 0,001). A diferença não foi significativa entre o TAG e o Pascal (p = 0.30), ou entre o TAG e o Tono-Pen (p = 0.68). Houve excelente concordância entre o TAG e o TP (CCC = 0,98; intervalo de confiança 95% (IC95%) = 0,97 - 0,99), já entre o TAG e o Pascal (CCC = 0,89; IC95% = 0,82 - 0,94) e entre o TAG e o Tono-Pen (CCC = 0,92; IC95% = 0,87 - 0,95). O gráfico tipo Bland-Altman TAG x Perkins demonstrou diferença média de 0,47 mmHg com intervalo de 95% (I95%) situado entre -0,98 e 1,92 mmHg. A dispersão das diferenças seguiu caráter aleatório. Os outros dois tonômetros também tiveram suas dispersões em caráter aleatório. TAG em relação ao tonômetro de Pascal apresentou diferença média de -0,3 mmHg (I95% = -4,2 a 3,6 mmHg). A diferença média do TAG em relação ao Tono-Pen foi de -0,1 mmHg (I95% = -3,7 a 3,5 mmHg). Em 21% dos pacientes, o tonômetro de Pascal apresentou diferenças maiores de 2 mmHg em relação ao TAG, ao passo que no Tono- Pen essa proporção foi de 17,3%, e o tonômetro de Perkins não apresentou em nenhum dos pacientes diferenças maiores que estes limites. CONCLUSÕES: A ceratometria, paquimetria e os diâmetros axial e corneal não se correlacionaram com a PIO obtida por meio do TAG, tonômetro de Perkins, Pascal ou Tono-Pen. As diferenças tonométricas entre TAG (padrão ouro) e os outros tonômetros também não se correlacionaram com esses parâmetros biométricos, com exceção da ceratometria média, que se correlacionou positiva e moderadamente com a diferença da PIO entre TAG e Tono-Pen. O tonômetro de Perkins apresentou concordância substancial com o TAG, já o Tono-Pen e o TCD apresentaram concordâncias moderadas, sendo a concordância do Tono-Pen maior que a do TCDOBJECTIVES: To compare the values of intraocular pressure (IOP) obtained by Perkins tonometer (PKT), Pascal dynamic contour tonometer (DCT) and Tono-Pen (TP), comparing then with Goldmann applanation tonometry (GAT), analyzing their correlations with ocular biometric parameters in patients with primary congenital glaucoma. METHODS: Prospective and cross-sectional study, including 46 patients (46 eyes) diagnosed with primary congenital glaucoma, between 12 and 40 years old, after obtaining informed consent. Keratometry was performed, followed by Goldmann applanation tonometry, Perkins tonometry, DCT and TP. The order of tonometries was randomized. The Goldmann tonometer was adopted as the gold standard. Ultrasound pachymetry, ultrasound biometry and corneal diameter measurement with surgical compass were also performed. The distributions of biometric parameters, as well as the tonometries were plotted and analyzed using Kolmogorov-Smirnov for acceptance of normality. Paired Student\'s t test for independent samples was used to compare the means of each tonometry with the gold standard. The correlations between biometric parameters and tonometries were performed by Pearson\'s product moment correlation coefficient and linear regression plots. The same procedure was done between biometric parameters and the differences between the three distinct tonometries and Goldmann tonometry. The agreement between tonometers and the GAT was performed through concordance correlation coefficient (CCC) and graphically by the Bland-Altman method. End point of 2 mmHg was adopted to evaluate clinical employability of these tonometers in patients with similar conditions. RESULTS: The Kolmogorov-Smirnov indicated acceptance of normality for all distributions studied (GAT, PKT, DCT, TP, corneal diameter, axial length, keratometry and pachymetry). All the Pearson´s product moment correlation coefficients between biometric parameters and each tonometry were not significant. The correlations between the biometric parameters and the differences between tonometries compared to the gold standard were not significant in most cases. The only exception was a positive and moderate correlation between the difference of the GAT and Tono-Pen versus the keratometry. The determintation coefficient revealed a considerable, but no large influence of K on the differences between GAT and Tono-Pen (r² = 0.16; p = 0.004). Student\'s paired t test showed a significant difference between GAT and PT (p < 0.001). The difference was not significant between the GAT and Pascal (p = 0.30), or between the GAT and Tono-Pen (p = 0.68). There was excellent agreement between GAT and PT (CCC = 0.98, 95% confidence interval (95% CI) = 0.97 to 0.99), as between GAT and Pascal (CCC = 0.90, 95% CI = 0.82 to 0.94) and between GAT and Tono-Pen (CCC = 0.92, 95% CI = .87 to .95). Bland-Altman plot GAT x Perkins showed a mean difference of 0, 47 mmHg with 95% CI located between -0.98 and 1.92 mmHg. The distribution of the IOP differences was aleatory. The other two differences` distributions also had aleatory characteristics. When comparing GAT with Pascal, the mean difference was -0.3 mmHg (95% CI = -4.2% to 3.6 mmHg). Mean difference between GAT and Tono-Pen was -0.1 mmHg (95% CI = -3,7 to 3.5 mmHg). Pascal tonometer showed a difference greater than 2 mmHg comparing to GAT in 21% of the patients, while with Tono-Pen this ratio was 17.3% and the Perkins tonometer did not present in any patient differences greater than these limits. CONCLUSIONS: The keratometry, pachymetry, corneal diameter and axial length did not correlate with IOP obtained by GAT, Perkins tonometer, Tono-Pen or Pascal. The differences between GAT (gold standard) and the other tonometers also did not correlate with these biometric parameters, with the exception of corneal curvature, which was positive and moderately correlated with the difference in IOP between GAT and Tono-Pen. GAT and Perkins tonometer showed substantial agreement, although Tono-Pen and DCT showed moderate agreement with GAT. The concordance obtained with Tono-Pen was higher than the concordance obtained with DCT
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Bergdahl, Emilia. "Jämförelse mellan rebound tonometri och non-contact tonometri." Thesis, Linnéuniversitetet, Institutionen för medicin och optometri (MEO), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-26309.
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Syfte:.Syftet med studien är att jämföra icare tonometri med NCT och se om de två metoderna får likvärdiga resultat. Studien ville även se vilken av metoderna som föredras av deltagarna. Metod: 85 personer deltog med medelålder 27 ± 9,2 år. Mätningarna utfördes på 82 av deltagarna i slumpmässig ordning på deras högerögon. I studien användes topcon CT-80A non-contact tonometer (topcon coroporation) och icare ® TA01i tonometer (icare Finland Oy). Resultat: Medelvärde för icare var 16,4 ± 3,9 mmHg. Medelvärdet för NCT var 15,6 ± 2,6 mmHg. Det var statistisk signifikant skillnad mellan metoderna (p = 0,001). Väldigt god positiv korrelation mellan icare och NCT (r = 0,85; y = 1,2905x - 3,7199). 91% av deltagarna föredrog icare framför NCT. Slutsats: Båda metoderna fungerar bra som screeningmetoder av IOP men icare har en tendens att ge högre värden än NCT. Icare tonometer var den metod som de flesta deltagarna föredrog. Det fanns en statistiskt signifikant skillnad mellan icare och NCT vilket tyder på att metoderna skiljer sig åt resultatmässigt.
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Allbaugh, Rachel A. "Ocular effects following aqueocentesis in dogs using variable needle sizes : fluorophotometric and tonometric evaluation." Thesis, Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/1428.
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Oehring, Daniela. "Ocular biomechanics of the anterior segment." Thesis, University of Plymouth, 2018. http://hdl.handle.net/10026.1/10647.
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The thesis investigates methods of examining corneal biomechanics using non-contact tonometry and introduces novel techniques to investigate corneal material properties in vivo. A comprehensive systems analysis of the CorvisST (CST) and Ocular Response Analyser (ORA) was performed. Pressure sensors were used to characterisation the airflow produced by the CST and the ORA. Distinct differences were observed between the central airflow pressures between the two devices: the CST pressure was higher and of shorter duration. Scheimpflug high-speed imaging via the CST allowed components of the corneal deformation to be investigated and the development of a 3D deformation matrix (time, depth and spatial resolution) through tracing of the anterior and posterior corneal surface. Measures of whole eye movement (WEM) with CST were found to be robust. WEM demonstrated an asymmetric profile and a correction method was developed to address the corneal deformation matrix for this asymmetry. Novel methods for characterisation of intrinsic material characteristics of the cornea were developed using numerical and graphical analytical procedures. Application of these parameters was tested on enucleated porcine eyes across a wide range of manometry internal ocular pressure (MIOP). The dynamic E-Modulus was found to be most affected by MIOP change. To investigate the in vivo distribution and heterogeneity of the corneal biomechanics, a novel set-up allowed the mapping of corneal biomechanics across the cornea using the CST (central, paracentral, peripheral) and ORA (central, peripheral). Biometric and demographic grouping of subjects allowed detection of discriminating factors between individuals. The results suggest that the in vivo cornea of healthy human adults can be characterised as a viscoelastic, damped system for longitudinal strain and a highly oscillating system for lateral strain. The cornea is approximately homogenous for measures of rigidity and dynamic E-Modulus but other corneal material characteristics (longitudinal and lateral strain, hysteresis, damping and compressibility) demonstrated regional differences. The experimental design employed allowed for strict control of biometric and biomechanical intersubject variables, based on gold-standard techniques as well as newly-developed methods, thereby creating a normative database for future use.
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Silva, Weriton Ferreira da. "Reabilitação cardiovascular de curto prazo em mulheres com diabetes mellitus tipo 2 : repercussões sobre o balanço redox, a função vascular e a qualidade de vida." Universidade Federal de Alagoas, 2009. http://repositorio.ufal.br/handle/riufal/650.
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Introduction: Diabetes is characterized by insufficient production of insulin and/or incapacity of this hormone in playing its functions. Such disease impairs the function of the endothelium, the latter capable of regulating the vascular tone and important in the control of inflammatory response as well. Once dysfunctional, the endothelium no longer exhibits such functions, occurring mostly redox imbalance, this one evident in diabetic patients. Nowadays, several studies point to endothelial dysfunction as a contributor in the development of diabetic vascular complications, while the practice of physical activity, although of low intensity, brings benefits in the handling of type 2 diabetes, including reduction of cardiovascular risk factors. Physical intervention as a therapeutic proposal appears to be a promising way in the clinical management of diabetes mellitus, probably avoiding the progression of systemic complications. Aim: To assess the vascular function and the REDOX balance in patients with type 2 diabetes mellitus (T2DM) before and after the cardiovascular rehabilitation for six weeks. Methods: 43 diabetic female patients aged 57.50 ± 2.02 years were selected from the ambulatory of Endocrinology at Prof. Alberto Antunes Teaching Hospital (Federal University of Alagoas). The diagnosis for T2DM was established according to the criteria of the Brazilian Society of Diabetes (2007). Initial assessment was performed by laboratory and clinical evaluation. The cardiovascular rehabilitation program consisted of six weeks of aerobic training (50 to 70% of the maximum heart rate), associated to endurance training. Four patients have completed the six weeks rehabilitation program. Assessment of biochemical profile (fasting and postprandial glucose, glicosilated hemoglobin, total cholesterol, VLDL, LDL, HDL, triglycerides, uric acid, albumin and creatinin), REDOX balance (SOD and catalase activity and lipid peroxidation) and quality of life (through the application of the SF-36) were performed before and after the rehabilitation program period. Indirect assessment of vascular function was performed by the Augmentation Index (AI), wave reflection, systolic and diastolic blood pressure and pulse pressure, which were obtained by the left radial artery tonometry (HEM-9000 AI device). Physical capacity was assessed by the six-minute walk test. Results: After rehabilitation, there was a significant reduction in the serum albumin levels (3.52 ± 0.478 vs 3.85 ± 0.50 mg/dL, P=0.0159) and an increase in the serum acid uric levels (5.00 ± 0.25 vs 4.57 ± 0.21 mg/dL, P=0.0298), without, however, alterations in the creatinin levels (P=0.3760). It was observed a reduction in the systolic and diastolic blood pressure (141.50 ± 3.67 vs 117.00 ± 6.01 mmHg, p<0.01; 77.75 ± 1.48 vs 71.25 ± 3.03 mmHg, P<0.05, respectively) and in the pulse pressure (63.75 ± 2.29 vs 45.750 ± 3.68 mmHg, P<0.01), without improvement in the Augmentation Index, with an improvement in five parameters during the assessment of the quality of life: physical functioning (25.00 ± 17.56 vs 93.75 ± 6.25 %, P<0.05), vitality (31.250 ± 10.48 vs 87.50 ± 5.20 %, P<0.05), social functioning (50.00 ± 17.68 vs 100.00 ± 0.00 %, P<0.05), role physical (47.50 ± 8.53 vs 92.50 ± 3.22 %, P<0.01) and bodily pain (21.62 ± 10.68 vs 65.75± 12.49 %, P<0.01). There were no statistically significant changes neither in the glycemic and lipid profiles nor in the functional capacity. Conclusion: The cardiovascular rehabilitation program during six weeks in diabetic patients was capable of promoting improvement in hemodynamic parametres and in the quality of life, without greater changes in the biochemical profile and functional capacity. These observations permit to consider that in diabetic patients the cardiovascular rehabilitation should be initiated as soon as possible to promote a reduction in the cardiovascular risk in these individuals.Introdução: O diabetes caracteriza-se pela produção insuficiente de insulina e/ou pela incapacidade desse hormônio em desempenhar suas funções. Tal doença prejudica a função do endotélio, tecido este capaz de regular o tônus vascular e a resposta inflamatória. Quando disfuncional, esta camada celular não mais exibe tais funções, ocorrendo, principalmente, o desbalanço redox, evidente em pacientes diabéticos. Atualmente, diversos estudos apontam para a disfunção endotelial como contribuinte para o desenvolvimento das complicações vasculares diabéticas, ao passo que a prática de atividade física, ainda que de baixa intensidade, traz benefícios no manejo do diabetes mellitus tipo 2, incluindo redução dos fatores de risco cardiovascular. Desta forma, a intervenção física como proposta terapêutica apresenta-se promissora no manejo clinico do diabetes mellitus, podendo evitar a progressão de complicações sistêmicas. Objetivo: Avaliar a função vascular e o balanço redox em pacientes portadores de diabetes mellitus tipo 2 (DMII), antes e após a reabilitação cardiovascular por seis semanas. Método: 43 pacientes do sexo feminino com idade média de 57,50 ± 2,02 foram selecionadas do ambulatório de Endocrinologia do Hospital Universitário Prof. Alberto Antunes (Universidade Federal de Alagoas). O diagnóstico de DMII foi estabelecido de acordo com os critérios da Sociedade Brasileira de Diabetes (2007). A avaliação inicial foi feita através de exames clínicos e laboratoriais. O programa de reabilitação cardiovascular consistiu de seis semanas de exercício aeróbio (50 a 70% da freqüência cardíaca máxima) associado a exercícios resistidos. Quatro pacientes completaram as seis semanas de reabilitação. Avaliação do perfil bioquímico (glicemia de jejum e pós-prandial, hemoglobina glicosilada, colesterol total, VLDL, LDL, HDL, triglicerídeos, ácido úrico, albumina e creatinina), balanço REDOX (atividades da SOD e catalase e peroxidação lipídica) e qualidade de vida (através da aplicação do SF-36) foram realizadas antes e após o programa de reabilitação. A avaliação indireta da função vascular foi realizada através do Augmentation Index (AI), onda de reflexão, pressões arteriais sistólica e diastólica e pressão de pulso, obtidos por tonometria da artéria radial esquerda (com o equipamento HEM-9000 AI). A capacidade física foi avaliada através do teste de caminhada de seis minutos. Resultados: Após a reabilitação, houve redução significativa dos níveis séricos albumina (3,52 ± 0,478 vs 3,85 ± 0,50 mg/dL, P=0,0159) e aumento dos níveis de ácido úrico (5,00 ± 0,25 vs 4,57 ± 0,21 mg/dL, P=0,0298), sem, entretanto, alterações dos níveis de creatinina (p=0,3760). Também foram reduzidas as pressões arteriais sistêmicas sistólica e diastólica (141,50 ± 3,67 vs 117,00 ± 6,01 mmHg, P<0,01; 77,75 ± 1,48 vs 71,25 ± 3,03 mmHg, P<0,05, respectivamente) e a pressão de pulso (63,75 ± 2,29 vs 45,750 ± 3,68 mmHg, P<0,01), sem redução no Augmentation Index, com melhora em cinco parâmetros da qualidade de vida: aspectos físicos (25,00 ± 17,56 vs 93,75 ± 6,25 %, P<0,05), vitalidade (31,250 ± 10,48 vs 87,50 ± 5,20 %, P<0,05), aspectos sociais (50,00 ± 17,68 vs 100,00 ± 0,00 %, P<0,05), capacidade funcional (47,50 ± 8,53 vs 92,50 ± 3,22 %, P<0,01) e dor (21,62 ± 10,68 vs 65,75 ± 12,49 %, P<0,01). Não foram observadas variações estatisticamente significativas para o perfil glicêmico, lipídico e capacidade funcional. Conclusão: O programa de reabilitação cardiovascular por seis semanas em pacientes diabéticas foi capaz de promover melhora em parâmetros hemodinâmicos e na qualidade de vida, sem maiores mudanças no perfil bioquímico e capacidade funcional. Estas observações permitem considerar que em pacientes diabéticos a reabilitação cardiovascular deve ser iniciada o mais precoce possível a fim de promover redução do risco cardiovascular nestes indivíduos.
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Bacchin, Angela Beatriz de Oliveira. "Curva diária e valores da pressão intraocular obtidos com tonômetro de rebote em equinos hígidos da raça crioula (Equus caballus)." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/181313.
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A tonometria é de extrema importância durante o exame oftálmico, pois auxilia no diagnóstico e no acompanhamento do glaucoma e de inflamações intraoculares. No entanto, os valores da pressão intraocular podem sofrer influência do momento do dia em que o exame é realizado. Objetivou-se avaliar a pressão intraocular (PIO) com tonômetro de rebote em equinos hígidos da raça Crioula em diferentes horários do dia. Foram avaliados ambos os olhos de 25 cavalos da raça Crioula, machos ou fêmeas, subdivididos em três categorias de diferentes idades designadas por GI: nove animais (3-5 anos de idade), GII: oito animais (6-8 anos de idade) e GIII: oito animais (9-16 anos de idade). Previamente à tonometria foram realizados teste lacrimal de Schirmer, biomicroscopia com lâmpada de fenda, prova da fluoresceína e oftalmoscopia indireta em todos os equinos. Num mesmo dia foram realizadas sete aferições da PIO (às 6, 9, 12, 15, 18, 21 e 24 horas). A avaliação estatística utilizou o teste T de Student quando haviam dois grupos de comparações, e o teste de análise de variância (ANOVA) para as variáveis PIO, horário de aferição (tempo) e categoria de idade. O valor médio da pressão intraocular obtido foi de 28,4±3,7 mmHg considerando todos os animais avaliados. Os valores médios da pressão intraocular para os equinos de GI, GII e GIII foram 29,2±3,5 mmHg, 28,4±4,3 mmHg e 27,7±3,2 mmHg, respectivamente. Não houve diferença estatisticamente significativa entre os olhos direito e esquerdo (p= 0,257), nem entre sexos (p= 0,284). Quando comparadas as idades, a PIO média foi significativamente maior nos indivíduos jovens (p= 0,012). Não houve diferença estatisticamente significativa entre os diferentes horários do dia (p= 0,560). Os valores da PIO aferidos com o tonômetro de rebote em equinos da raça Crioula sofreram influência da idade. Os valores da pressão intraocular média obtidos com tonômetro de rebote em equinos hígidos não variaram em diferentes horários ao longo do dia.The tonometry is extremely important during ophthalmic examination, because assists in the diagnosis and follow-up of glaucoma and intraocular inflammation. However, intraocular pressure values may be influenced by the moment of the day it is measured. The objective was to evaluate the intraocular pressure (IOP) with Rebound Tonometer in healthy horses of the Crioula breed at different times of the day. Twenty five horses, male or female, were divided into three groups by age: Group I: nine horses (3-5 years old), Group II: eight horses (6-8 years old), and Group III: eight horses (9-16 years old). Ophthalmic examination was performed previously by Schirmer Tear Test, slit lamp biomicroscopy, fluorescein test and indirect ophthalmoscopy in all horses. Seven measurements of intraocular pressure were assessed on the same day (at 6, 9, 12, 15, 18, 21 and 24 hours).The Student’s T Test statistical analysis was used when there was two groups of comparisons, and the Analysis of Variance (ANOVA) was used for variables IOP, measurement time and age category. The average value of intraocular pressure was 28.4 ± 3.7 mmHg considering all the animals evaluated. The mean intraocular pressure for groups I, II and III were 29.2 ± 3.5 mmHg, 28.4 ± 4.3 mmHg and 27.7 ± 3.2 mmHg, respectively. There was no statistically significant difference between right and left eyes (p = 0.257), nor between genders (p = 0.284). When compared to the ages, the average IOP was significantly higher in young animals (p = 0.012). There was no statistically significant result between the different times of the day (p = 0.560). The IOP values measured with rebound tonometer in Crioula horses were influenced by age. The average intraocular pressure values obtained with rebound tonometer in healthy horses did not change with time of day.
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Fröjse, Rolf. "Exploring Intestinal Ischemia : An experimental study." Doctoral thesis, Umeå universitet, Kirurgisk och perioperativ vetenskap, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-461.
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Background and aims: Unrecognized intestinal mucosal ischemia in severely ill patients may trigger development of multiple organ failure. Such ischemia can be evaluated by intraluminal tonometry reflecting mucosal PCO2 and intramucosal pH (pHi). The aims were to develop an apparatus for continuous saline tonometry (CST), to analyse circulatory control mechanisms during intestinal hypoperfusion and to evaluate the effect of dopexamine on intestinal circulation. Methods: A modified standard tonometry catheter was integrated in a closed system with circulating saline. By measuring saline PCO2 in a measurement unit pHi could be calculated. This novel system was tested in vitro and in vivo. In a porcine study, CST was evaluated against standard saline tonometry, tissue oxygenation (PO2 TISSUE), jejunal mucosal perfusion (laser doppler flowmetry; LDF) and mesenteric net lactate flux during graded reductions of superior mesenteric arterial pressure (PSMA). Local control mechanisms for maintenance of intestinal oxygenation were analysed. Effects of dopexamine on the intestinal vascular bed were explored. Mucosal lactate production was assessed by microdialysis. Results: CST measured accurate PCO2 values and changes in pHi during restricted intestinal circulation and at reperfusion. Local control mechanisms were insufficient at a PSMA of 30 mmHg, pHi was reduced to 7.10 and intestinal net lactate production was demonstrated. Absence of anaerobic intestinal metabolism was verified at PSMA ≥ 50 mmHg, pHi ≥ 7.22 and a PCO2 gap ≤ 15.8 mmHg. Dopexamine induced negative regional metabolic effects at the lowest PSMA, as expressed by decreased PO2 TISSUE and pHi, increased PCO2 gap and intestinal net lactate production. Conclusions: CST reflected changes in pHi, induced by intestinal hypoperfusion and at reperfusion. Levels of PSMA, pHi and PCO2 gap as indicators of aerobic conditions were defined. Dopexamine induced a decrease of PO2 TISSUE and pHi as well as an increase in lactate flux at the lowest PSMA level.
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Fossey, Marcelo Andre. "Tonometro eletronico para a medida da pressão intraocular." [s.n.], 1985. http://repositorio.unicamp.br/jspui/handle/REPOSIP/260015.
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Orientador: Wang BinsengDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Campinas
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Resumo: Devido às graves implicações sociais do glaucoma, e ao fato dele ser relativamente imperceptível no início, é necessário a avaliação da pressão intra-ocular (PIO) toda vez que se efetua o "check-up"., pois pressões prolongadas acima de 21 mmHg podem causar alteração do campo visual e, se não tratado em tempo, cegueira ao paciente. Atualmente os tonômetros utilizados no Pais são importados, apresentando alto custo, baixa precisao (tonômetro de Goldmann) e pouca confiabilidade (tonômetros eletrônicos). Foi projetado e construido um tonômetro eletrônico, com materiais e componentes facilmente encontráveis no mercado nacional. A PIO é medida por uma ponta de prova, no centro da qual existe um pino rigidamente acoplado a uma cerâmica piezoelétrica, que ao ser deformada pela PIO produz uma tensão elétrica e, ao se detetar eletronicamente a condição de aplanação, é registrado o valor da PIO num display digital. Para aumentar a confiabilidade, o tonômetro foi montado num suporte com o formato de revólver, com dois suportes laterais. Este tonômetro pode ser utilizado com.o paciente na posição vertical ou reclinado, sem o auxílio da lâmpada de fenda.
Abstract: The grave social consequences of glaucoma and the fact its onset is relatively imperceptivable make evaluation of the intraocular pressure (IOP) essential at each Iredical examination. Prolonged IOPs above 21 nmHg may cause alterations in the visual field and, if not treated, blindness in the patient. At the present time, alI tonometers used in Brazil are irnported. 1n general, they present either high cost and low precision (Goldman tonometers) or little reliability (electronic tonometers). An electronic tonometers was designed and built using materiaIs and corrponents available in Brazil. The IOP is measured with a probe at the center of which exists a pin fixed rigidly onto a piezoelectric transducer, whose deforrnation by tpe IOP produces an electric signal. As the cornea is depressed by the probe, the applanation, condition is detected electronically and the value of IOP thus detected is displayed digitally. To provide reliable measurerrents, the tonometer was mounted in front of a pistol-like holder with two supports to be positioned on, the facial banes. The instrument may be used with the patient in any position without the need af a slit lamp.
Mestrado
Mestre em Engenharia Elétrica
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Nipp, Amy Suzanne. "Benchtop Alignment Stand and Circuitry for Tonometer Prototyping." Thesis, The University of Arizona, 2014. http://hdl.handle.net/10150/321906.
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Polyzoev, Vasco. "HAND-HELD TONOMETER FOR TRANSPALPEBRAL INTRAOCULAR PRESSURE MEASUREMENT." Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/202517.
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This dissertation describes the development of a portable, hand-held tonometer for measurement of the intraocular pressure through the eyelid. The primary use of such device will be by people diagnosed with the eye disease glaucoma. Glaucoma is the second leading cause of blindness in the world and is asymptomatic to the patient in its early stages. This allows it to remain undiagnosed for prolonged periods, causing irreversible damage to the affected person's vision. Elevated intraocular pressure is the main risk factor associated with the development of glaucoma, and is currently the only symptom that is treatable for the slowing down or stopping of the progression to blindness caused by the disease. The effectiveness of the medications or procedures aimed at reducing the pressure to below risk levels is currently monitored through visits to the ophthalmologists' offices, which makes the frequent monitoring of the pressure inconvenient, expensive and sometimes impossible. Due to the variation of the pressure throughout the day and during different activities or food and beverage intake, the portability of the device is important in order to allow the user to carry it with them and take measurements as frequent as needed. The option to perform the measurement through the eyelid avoids direct contact with the eye, eliminating possible discomfort, the use of anesthetics, and the risk of contamination.Several designs and measuring concepts are evaluated using a custom made pressure regulation system. A series of prototypes have been built and tested and the results are reported in the respective sections of the dissertation. The final concept selected for the measurement technique was based on multiple force probe indentation and a custom MEMS-based force sensor for it was designed and tested.The main contributions of this dissertation are the design, fabrication and test of the prototype devices and the MEMS force sensors. The obtained results and experience described here can serve as a platform for further optimization and improvement of the device, and eventual development of a prototype capable of performing clinical research studies and passing FDA approval for home and clinical use.
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Niño, Montero José Segundo. "Comparación de la tonometría de contorno dinámico (Pascal) y tonometría de aplanación (Goldmann) en relación al grosor corneal y curvatura corneal." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2009. https://hdl.handle.net/20.500.12672/2456.
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Objetivo: Determinar la diferencias en las mediciones de tonometría de contorno dinámico (TCD) y la tonometría de aplanación (TAG) al relacionarlas con el grosor y la curvatura corneal.
Materiales y métodos: Estudio transversal, comparativo. Se obtuvo una muestra por conveniencia, esto incluyó a 116 ojos de pacientes que acudieron al programa social del Instituto de Ojos Oftalmosalud, sin patología ocular demostrada, entre los meses de febrero a Abril del 2009. Se tomaron medidas del grosor, curvatura corneal, presión intraocular por TCD y TAG
Resultados: La edad promedio de los participantes fue 55 años, el 52.58% varones. La media de la PIO por contorno dinámico fue 19.3 mm Hg y de la tonometría de aplanación 16.32 mm Hg, existiendo diferencias significativas entre ambas mediciones de PIO (p menor 0,0006). El grosor de la córnea central por paquimetría fue 539.4 en promedio y la media de la curvatura corneal en dioptrías de 43.28. Las comparaciones de las medias de la PIO de la TAG y TCD según el grosor corneal central (GCC) son significativas en las medidas menores a 500 micras (p menor 0.000001). Según la curvatura corneal se mantienen estas diferencias de manera significativa, es mayor con el TCD.
Conclusiones: La tonometría de contorno dinámico sobreestima significativamente la PIO comparada con la tonometría de aplanación. La PIO evaluada con ambos instrumentos comparadas con el grosor corneal muestran diferencias significativas, siendo similares en córneas entre 500 a 549 micras.--- Objective: To determine the differences in the measurements of Dynamic contour tonometry and Goldmann applanation tonometry in relation with the thickness and the corneal curvature. Methodology: Study transverse, a sample was obtained by convenience, included 116 patients’ eyes went to the Oftalmosalud social program, without ocular pathology, showed through February to April, 2009. They took measures of the thickness, corneal curvature, pressure for CDT and AGT. Results: The age average of the participants was of 55 years, 52.58% males. The stocking of the IOP one for contour dinamic was 19.3 mmHg and for applanation tonometry 16.32mmHg, existing significant differences among both mensurations of IOP (p less 0, 0006). The thickness of the central cornea for paquimetry was 539.4 on the average and the stocking of the corneal bend in dioptrias of 43.28. The comparisons of the stockings of the IOP one of AGT and CDT according to the thickness corneal power station (CCT) are significant in the measures smaller to 500 microns (p less 0.000001). According to the corneal curvature stays with significant differences ways being bigger with CDT. Conclusions: The tonometry of contour dinamic overestimates the IOP one compared with the applanation tonometry significantly. The IOP one evaluated with both instruments compared with the corneal thickness shows significant differences, being similar in corneas among 500 to 549 microns.
Tesis