Dissertations / Theses on the topic 'Intracavitaire'
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Facy, Olivier. "Optimisation des techniques de chimiothérapie intracavitaire." Thesis, Dijon, 2013. http://www.theses.fr/2013DIJOMU07/document.
Full textIntroduction. In order to achieve a good effect, chemotherapy drugs need to penetrate into the peritoneal (HIPEC) or pleural tissue. Hyperthermia and high-pressure may enhance this penetration. The aim of this study was to evaluate their peritoneal effect and to establish the best technique to it. A feasibility study of an intrapleural high-pressure was an essential step to export these effects to the thoracic space. Methods. Four groups of pigs underwent an open HIPEC with a constant concentration (150 mg/l) of oxaliplatin during 30 minutes either in normothermia, or in hyperthermia (42-43°C); and either with atmospheric pressure or with high-pressure (25 cmH2O). Two more groups underwent a closed procedure with hyperthermia and either high-pressure or very high-pressure (40 cmH2O). The systemic and tissue absorption of oxaliplatin were studied. The haemodynamic and respiratory tolerance of a pleural infusion was also tested in 21 pigs with and without associated resection; with and without chemotherapy infusion (cisplatin + gemcitabin) and at various levels of pressure (from 15 to 25 cmH2O). Results. Hyperthermia enhances the concentrations of platinum in visceral surfaces (p=0.0014), whereas high-pressure enhances it both in visceral and in parietal surfaces (p= 0.0058 and p= 0.0044, respectively). Their association obtains the highest concentrations both in the visceral (p= 0.00001) and the parietal peritoneum (p= 0.0003). The concentrations obtained during closed procedure are lower than those achieved with the open technique, even with 40 cmH2O of pressure. A 60-minutes intrapleural chemotherapy perfusion with 20 cmH2O of pressure without any lung resection was the maximal tolerated level. Conclusion. During HIPEC, hyperthermia improves the penetration of oxaliplatin in the visceral peritoneum, whereas high-pressure is effective in both peritoneal surfaces. Their association is synergic and the open technique seems to be the best one to deliver it. An intrapleural chemotherapy with a 20 cmH2O pressure is feasible in this model
Astoul, Philippe. "Immunotherapie intracavitaire : administration intrapleurale d'interleukine-2 recombinante dans la traitement des cancers pleuraux." Aix-Marseille 2, 1994. http://www.theses.fr/1994AIX22961.
Full textChitnalah, Ahmed. "Dispositif ultrasonore pour hyperthermie intracavitaire : Applications envisagées aux traitements des tumeurs cancereuses prostatiques ou vaginales." Nancy 1, 1990. http://docnum.univ-lorraine.fr/public/SCD_T_1990_0422_CHITNALAH.pdf.
Full textSpasic, Estelle. "Dosimétrie in vivo intracavitaire basée sur la luminescence stimulée optiquement de l'Al2O3 : C dédiée à la curiethérapie." Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0270/document.
Full textThe brachytherapy is an old technique using sealed radioactive sources of low or average energy. This technique is still therapeutically and economically relevant today and always evolving (e.g. High Dose Rate (HDR) brachytherapy). This treatment enables to deliver a high dose of irradiation in a limited tumoral volume and enables to minimize the risk of radiation-induced cancer as preserving the Organs at Risks (OAR). However, this technique generates high dose gradients, which makes in vivo dosimetry difficult to implement. Hence, the deviations observed between doses delivered and prescribed are often up to the maximal deviation tolerated by the nuclear safety regulations (± 5%) in conformational radiotherapy. Those regulations have been made mandatory in France since 2011. This thesis has been done within the framework of the ANR-TECSAN INTRADOSE project and is based on the past technological benefits demonstrated during the MAESTRO European project and the ANR-TECSAN CODOFER project, in particular a RL/OSL multichannel instrumentation (Radioluminescence - Optically Stimulated Luminescence) made and validated in preclinical evaluation during the MAESTRO project. The purpose of the INTRADOSE project is to demonstrate the feasibility of the intracavitary In Vivo Dosimetry (IVD) by dosimetric catheter using optical fibers and alumina crystals Al2O3:C with the aim of improving the safety of patients treated by HDR brachytherapy. This new probe enables to measure a dose distribution (several points) close to the OAR, it offers a little diameter (
Leroy, Henri-Arthur. "Thérapie photodynamique au 5-ALA appliquée aux glioblastomes." Thesis, Université de Lille (2022-....), 2022. http://www.theses.fr/2022ULILS007.
Full textHigh-grade primary brain tumors represent a major care issue. Indeed, the mostfrequent of these tumors, glioblastoma (GBM), have an appalling prognosis. Their mediansurvival is about 15 months when patients have undergone optimal excision surgery followedby the recommended adjuvant treatments of radiotherapy and chemotherapy. In spite of thesetreatments, recurrence is the rule, and most of the time close to the initial excision cavity. Newtechniques have been developed to improve local control of the tumor, such as the implantationof carmustine wafers in the surgical cavity. However, the benefit of this type of complementarytherapy is limited.It is in this context that the idea of applying photodynamic therapy (PDT) to GBM hasemerged. This treatment is based on the synchronous presence of three elements: aphotosensitizer molecule, oxygen and illumination at a specific wavelength triggering ametabolic cascade promoting the death of cancerous glial cells. Thanks to the development ofphotosensitizers specific to cancer cells (PpIX 5-ALA), especially glial cells, brain PDT appearsto be a promising additional therapy, potentially having a synergistic effect with gold-standardadjuvant treatments.In the context of operable GBM, intracavitary PDT has been evaluated by our team ina phase I clinical trial (INDYGO), demonstrating its safety and confirming encouragingoncological results. The evaluation of the optimal light dose for deeper treatment remains tobe done. A phase II trial (DOSYNDIGO) is dedicated to this and is currently in the inclusionperiod.However, some lesions, because of their topography, cannot be operated on withoutcausing permanent neurological deficits that are disabling for the patient prognosis. Theabsence of initial excisional surgery further compromises the prognosis of the disease byreducing the period of progression-free survival and total survival. In patients who could notbenefit from excisional surgery, this additional intra-cavity treatment could not take place. Thisis why we conducted our research work towards interstitial PDT. This involves introducing oneor more optical fibers under stereotactic conditions into the tumor or in its immediate vicinity inorder to deliver the required illumination without performing a craniotomy or dissecting thebrain parenchyma. This minimally invasive treatment represents a real opportunity for allpatients who cannot be operated on, either at the initial diagnosis of their GBM or at recurrence.This interstitial treatment would complement standard of care without modifying it. We reportedthe current data regarding iPDT available in the literature, then we proposed original data witha standardized clinical procedure based on a dedicated dosimetry algorithm, before lookingforward to a phase I clinical trial
Jiménez-Pérez, Guillermo. "Deep learning and unsupervised machine learning for the quantification and interpretation of electrocardiographic signals." Doctoral thesis, Universitat Pompeu Fabra, 2022. http://hdl.handle.net/10803/673555.
Full textElectrocardiographic signals, either acquired on the patient’s skin (surface electrocardiogam, ECG) or invasively through catheterization (intracavitary electrocardiogram, iECG) offer a rich insight into the patient’s cardiac condition and function given their ability to represent the electrical activity of the heart. However, the interpretation of ECG and iECG signals is a complex task that requires years of experience, difficulting the correct diagnosis for non-specialists, during stress-related situations such as in the intensive care unit, or in radiofrequency ablation (RFA) procedures where the physician has to interpret hundreds or thousands of individual signals. From the computational point of view, the development of high-performing pipelines from data analysis suffer from lack of large-scale annotated databases and from the “black-box” nature of state-of-the-art analysis approaches. This thesis attempts at developing machine learning-based algorithms that aid physicians in the task of automatic ECG and iECG interpretation. The contributions of this thesis are fourfold. Firstly, an ECG delineation tool has been developed for the markup of the onsets and offsets of the main cardiac waves (P, QRS and T waves) in recordings comprising any configuration of leads. Secondly, a novel synthetic data augmentation algorithm has been developed for palliating the impact of small-scale datasets in the development of robust delineation algorithms. Thirdly, this methodology was applied to similar data, intracavitary electrocardiographic recordings, with the objective of marking the onsets and offsets of events for facilitating the localization of suitable ablation sites. For this purpose, the ECG delineation algorithm previously developed was employed to pre-process the data and mark the QRS detection fiducials. Finally, the ECG delineation approach was employed alongside a dimensionality reduction algorithm, Multiple Kernel Learning, for aggregating the information of 12-lead ECGs with the objective of developing a pipeline for risk stratification of sudden cardiac death in patients with hypertrophic cardiomyopathy.
Ruth, Serge van. "Hyperthermic intracavitary chemotherapy in abdomen and chest." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2003. http://dare.uva.nl/document/69072.
Full textHutchinson, Erin R. "Intracavitary ultrasound phased arrays for thermal therapies." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/43336.
Full textBuchanan, Mark Thomas 1967. "An ultrasound phased array system for intracavitary hyperthermia." Thesis, The University of Arizona, 1992. http://hdl.handle.net/10150/278159.
Full textKhoury, Dirar Shafiq. "Recovery of endocardial potentials from intracavitary potential data." Case Western Reserve University School of Graduate Studies / OhioLINK, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=case1056746257.
Full textSevero, Luiz Carlos. "Colonizacao intracavitaria pulmonar por aspergillus niger : analise de suas peculiaridades." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 1987. http://hdl.handle.net/10183/1422.
Full textDiederich, Chris John. "The design and development of intracavitary ultrasound arrays for hyperthermia." Diss., The University of Arizona, 1990. http://hdl.handle.net/10150/185172.
Full textLeung, To-wai. "High-dose-rate intracavitary brachytherapy in the treatment of nasopharyngeal carcinoma." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/HKUTO/record/B39557315.
Full text梁道偉 and To-wai Leung. "High-dose-rate intracavitary brachytherapy in the treatment of nasopharyngeal carcinoma." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B39557315.
Full textPike, G. Bruce (Gilbert Bruce). "Three dimensional stereotaxic intracavitary and external beam isodose calculation for treatment of brain lesions." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=65439.
Full textRizzuto, Cristiana. "Identificazione dell'attivazione del fascio di HIS nei segnali intracavitari in tachicardia sopraventricolare da rientro nodale." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
Find full textSokka, Shunmugavelu D. (Shunmugavelu Doraivelu) 1975. "Design and evaluation of linear intracavitary ultrasound phased array for MRI-guided prostate ablative therapies." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/80207.
Full textIncludes bibliographical references (p. 76-82).
by Shunmugavelu D. Sokka.
S.M.
Segala, James J. "Interface dosimetry for electronic brachytherapy Xoft Axxent intracavitary breast balloon applicators and fluorescence anisotropy imaging of quantum dots /." View online ; access limited to URI, 2009. http://0-digitalcommons.uri.edu.helin.uri.edu/dissertations/AAI3368005.
Full textMerrilees, N. Katherine (Ngaire Katherine) 1974. "Design of control systems for focused and unfocused intracavitary ultrasound arrays for the thermal treatment of prostate disease." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/9623.
Full textIncludes bibliographical references (leaf 102).
Heat transfer in tissue during induced hyperthettnia treatments for prostate disease can be modeled as a multi-input multi-output (MIMO) system. For both focused and unfocused ultrasound arrays, the control of this MIMO system can follow either of two paths. First, a method of system identification can be used to derive a system model from which a gain matrix for a controller can be calculated with methods like that of the linear quadratic regulator (LQR). Second, a trial and error controller can be designed and tuned for each new treatment. Although the first option has clear benefits, this work shows that, with MRI thermometry, the ti.me delay in the temperature feedback loop is sufficient to make any method of system identification difficult within the ti.me constraints of a clinical setting. A proportional plus integrator plus derivative (PID) controller was designed to control the system in computer simulations. This single-input, single-output (SISO) controller was weighted to better control the system by providing parameters scaled to compensate for the geometry of the treatment and thermal coupling of tissue. While the controller performed very well under the conditions for which it was tuned, the level of performance decreased when the parameters of the simulation, such as the rate of perfusion in the tissue were altered. For the unfocused array, a program was written in C++ to run the array and implement the controller for a hyperthermia treatment using MRI thermometry for the feedback signal.
by N. Katherine Merrilees.
M.Eng.
Souza, Fernando Sergio Oliva de. "Aspectos tecnicos da cateterização do seio coronariano baseado no componente atrial do eletrograma intracavitario durante o procedimento de implante de marcapasso biventricular." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/311523.
Full textTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
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Resumo: A estimulação elétrica biventricular apresenta bons resultados no tratamento da insuficiência cardíaca congestiva refratária em portadores de cardiomiopatia dilatada com distúrbios de condução interventricular. OBJETIVO: Apresentar proposição utilizando técnica original simplificada para o implante de eletrodo de estimulação ventricular esquerda epicárdica, baseado na anatomia radiológica e no eletrograma intracavitário,enfatizando o componente atrial, demonstrando o resultado, complicações, ressaltando tempo total de utilização de fluoroscópio. CASUÍSTICA E MÉTODO: De Outubro de 2001 a Março de 2007 foram realizados 234 implantes de marca-passo biventricular em pacientes previamente selecionados, utilizando-se anatomia radiológica e observação de eletrograma intracavitário, dando-se prioridade ao componente atrial, demonstrando a taxa de sucesso, complicações e tempo total de utilização de radioscopia. RESULTADOS: O implante do sistema, utilizando-se a estimulação do ventrículo esquerdo via seio coronariano não foi possível em 19(8,1%) pacientes. Em 30(12,8%) pacientes foram observadas dificuldades na canulação do óstio coronário e em 52(22%) pacientes observaram-se dificuldades de progressão do eletrodo através do seio coronário. O tempo médio de utilização de radioscopia foi 18,69(±15,2) min. CONCLUSÃO: A utilização da técnica simplificada para cateterização do seio coronário sem utilização de bainha, baseada na anatomia radiológica e no eletrograma intracavitário, enfatizando o componente atrial, no tratamento de portadores de cardiomiopatia dilatada avançada, pela terapia de ressincronização cardíaca, demonstrou resultado satisfatório, índice de complicações pequeno, e baixa exposição do operador a radiação ionizante
Abstract: Biventricular pacing has present good results in treatment of congestive cardiac heart failure in patients with dilated miocardyopathy and interventricular conduction disturbance. PURPOSE: to present a proposal of using a original simplified technique for left epicardial ventricular lead stimulation, based on the radiological imaging of the anatomy and intracavitary electrogram, emphasizing the atrial component, showing the results, complications, highlighting the total fluoro time. METHODS: From October, 2001 up to March, 2007, 234 biventricular pacemaker implantations were performed in previously selected patients, using radiological anatomy and observation of the intracavitary electrogram, focusing on the atrial component, and showing the success rate, complications and total time of radioscopy utilization. RESULTS: The implantation of the system using left ventricular pacing via coronary sinus was not possible in 19(8,1%) patients. Difficulties on the cannulation of the coronary ostium were felt in 30(12,8%) patients and difficulties of lead advancement through the coronary sinus were felt in 52(22%) patients. The mean time of radioscopy utilization was 18.69(±15,2) min. CONCLUSION: the use of a simplified technique for coronary sinus cannulation without the aid of a sheath, based on the radiological imaging of the anatomy and intracavitary electrogram, emphasizing the atrial component, for the treatment of advanced dilated cardiomyopathy patients with cardiac resynchronization therapy, has shown satisfactory results, low incidence of complications, and low exposure of the operator to ionizing radiation
Doutorado
Cirurgia
Doutor em Cirurgia
Pané, Alemany Regina. "Eficacia de la electroestimulación perineal de superficie versus la electroestimulación intracavitaria en el tratamiento de la incontinencia urinaria secundaria a prostatectomía radical: ensayo clínico aleatorizado." Doctoral thesis, Universitat Autònoma de Barcelona, 2021. http://hdl.handle.net/10803/671973.
Full textIntroducción: En la actualidad, la prostatectomía radical es el tratamiento de elección para los hombres con cáncer de próstata localizado,sin embargo, algunos pacientes sufren de incontinencia urinaria (IU) después de la cirugía. Esta pérdida de orina se convierte en un problema físico, emocional, psicosocial y económico. La fisioterapia del suelo pelviano es un tratamiento conservador, indoloro y económico para esta situación en concreto, y dentro de la misma encontramos como técnicas habituales el entrenamiento de la musculatura del suelo pelviano y la electroestimulación muscular perineal. Como objetivo principal se pretende comparar la eficacia del tratamiento con electroestimulación perineal de superficie versus el mismo tratamiento aplicado de manera intra-cavitaria, en la reducción de la IU secundaria a prostatectomía radical, y su repercusión sobre la calidad de vida. Material y métodos: Se realizó un ensayo clínico controlado y aleatorizado de equivalencia a simple ciego. Se generó una secuencia de asignación aleatoria a razón 1:1 y se realizó una inclusión consecutiva hasta alcanzar un total de 70 pacientes. Los grupos recibieron 1 sesión semanal durante 10 semanas consecutivas. El grupo intervención (GI) realizó la técnica con electrodos de superficie y el grupo control (GC) con sonda intraanal. Se recogieron los datos basales, en las semanas 5 y 10, y a los 6 meses posteriores a la finalización del tratamiento. Los gramos de orina perdidos medidos con el Pad Test 24h fue considerada la variable principal. Otras variables de estudio fueron la calidad de vida relacionada con la salud (CVRS) medida con los cuestionarios ICIQ-SF, I-QOL y SF-12, el estado de la musculatura del suelo pelviano, la continuidad y adherencia al tratamiento, los efectos adversos y la satisfacción con la terapia. Resultados: Se incluyeron un total de 70 hombres con una media de edad de 62,8 (DE 9,4) años. Todos habían sido intervenidos quirúrgicamente de prostatectomía radical y posteriormente presentaron IU derivada de esta cirugía. Los participantes presentaron un Pad Test 24h basal medio de 328,3 (DE 426,1) gramos. El Pad Test mostró una disminución significativa de los gramos de orina perdidos a las 5 semanas (121,7 gr en el GC y 159,1 en el GI) y 10 semanas (235,8 gr en el GC y 248,5 en el GI) de tratamiento en ambos grupos (GC p<0,001 y GI p<0,001). La diferencia dejó de ser significativa una vez finalizado el tratamiento durante los 6 meses posteriores (17,3 gr en el GC, p=0,230 y 11,7 gr en el GI, p=0,438). Los cuestionarios ICIQ-SF, I-QOL y SF-12 también mostraron una mejora significativa en la CVRS en los diferentes periodos de evaluación. En el análisis de las diferencias entre los dos tratamientos, en relación a la variable principal (Pad Test 24h) y en relación al resto de variables con valores recogidos mediante los cuestionarios de CVRS, se observa la ausencia de significación estadística. Conclusiones: Los resultados sobre la equivalencia terapéutica de la EEM aplicada con electrodos de superficie y la EEM aplicada con sonda intraanal no son concluyentes y, por tanto, no permiten establecer la equivalencia terapéutica entre ambas modalidades de tratamiento. Sin embargo, la disminución en los gramos de orina perdidos a lo largo de la terapia es clínica y estadísticamente significativa en ambos grupos; además, las diferencias en las pérdidas de orina entre el grupo intraanal y el grupo de superficie no son significativas, es decir, la EEM parece ser eficaz y la eficacia de las dos formas de administración no ser diferente desde el punto de vista estadístico. La utilización de la EEM mejora significativamente la CVRS de los participantes desde el inicio al final del tratamiento con los dos modos de aplicación.
Introduction: Radical prostatectomy is the gold standard treatment for men with localized prostate cancer. This technique is associated with post-operative urinary incontinence. Pelvic floor physiotherapy is a conservative, painless and economical treatment for this specific situation. Kegel exercises and perineal electrostimulation are common techniques to train pelvic floor muscles. The perineal electrostimulation can be applied to the patient with surface electrodes or by an intra-cavitary anal probe. The main objective is to compare the efficacy of the treatment with transcutaneous perineal electrostimulation versus the same intra-cavitary treatment to reduce the magnitude of urinary incontinence after radical prostatectomy, and the impact on the quality of life. Material and method: An equivalence, single-blind, randomized controlled trial was conducted. The groups received 1 weekly therapy session for 10 consecutive weeks. The intervention group (IG) performed the technique with surface electrodes and the control group (CG) with intraanal probe. Data were collected at baseline, at weeks 5 and 10, and 6 months after the end of treatment. Grams of urine lost, measured with the 24h Pad Test, was considered the main variable. Other study variables were health-related quality of life (HRQoL) measured with the ICIQ-SF, I-QOL and SF-12 questionnaires, pelvic floor musculature condition, continuity, adherence to treatment, adverse effects, and satisfaction with treatment. Results: A total of 70 men were included with a mean age of 62.8 (SD 9.4) years. All had undergone radical prostatectomy surgery and subsequently presented UI derived from this surgery. The participants presented a mean baseline 24h Pad Test of 328.3 (SD 426.1) grams. The Pad Test showed a significant decrease in the urine lost grams at 5 weeks (121.7 g in the CG and 159.1 g in the IG; p<0.001) and 10 weeks (235.8 g in the CG and 248.5 g in the IG; p<0.001) of treatment. The difference was no longer significant once the treatment was finished during the subsequent 6 months (17.3 g in the CG, p=0.230 and 11.7 g in the IG, p=0.438). The ICIQ-SF, I-QOL and SF-12 questionnaires also showed a significant improvement in HRQoL in the different evaluation periods. In the CG, an increase of 4.1 points in the ICIQ-SF, an increase of 21.1 points in the I-QOL, a decrease of 1.6 points in the mental and a decrease of 2.7 points in the physical dimensions of SF-12 were observed. In the IG, an increase of 3.8 points in the ICIQ-SF, an increase of 25.1 points in the I-QOL, a decrease of 1.6 points in the mental and a decrease of 2 points in the physical dimensions of SF-12 were also noted. In the analysis of the differences between the two treatments, in relation to the main variable (Pad Test 24h) and to the rest of variables collected through the HRQoL questionnaires, absence of statistical significance was found. Conclusions: The results on the therapeutic equivalence of perineal MES applied with surface electrodes and that applied with an intraanal probe are not conclusive and, therefore, do not allow establishing the therapeutic equivalence between both treatment modalities. However, the decrease in the grams of urine lost throughout the therapy is clinically and statistically significant in both groups (after 5 weeks of treatment and after 10 weeks of treatment); furthermore, the differences in urine losses between the intraanal group and the surface group are not significant, that is, MES seems to be effective and the efficacy of the two forms of administration not to be different from a statistical point of view. The use of electrostimulation improves significantly the HRQoL of the participants from the beginning to the end of the treatment with both modes of application.
Universitat Autònoma de Barcelona. Programa de Doctorat en Metodologia de la Recerca Biomèdica i Salut Pública
Baryalei, Mersa Mohammad. "Intracavitäre Herzmyxome." 1986. http://catalog.hathitrust.org/api/volumes/oclc/15797754.html.
Full textWu, Chin Hui, and 吳晋暉. "A Study on the Dose Distributions in Intracavitary Brachytherapy from an 192Ir Source." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/55maep.
Full text國立清華大學
核子工程與科學研究所
103
This study included two parts: (1) Dose distributions of an 192Ir brachytherapy source in different media ; (2) Influence of metal of the applicator on the dose distribution during brachytherapy. The AAPM TG-43 report provides dose calculation formula and dose parameters for brachytherapy. Although it can be used to evaluate the radiation dose received by the soft tissue, the human organs such as nasopharynx, esophagus, bronchi, lungs and bones are of different densities. AAPM TG-43 does not provide the corresponding dose parameters, therefore, the dose in these tissues can’t be assessed accurately. This may result in tumor recurrence or severe side effects in normal tissues. The MCNPX code is used to investigate the 192Ir dose distribution in water, bone and lung tissue. The glass dosimeter measurement was performed to verify the calculation results. It is found that dose rate constant, radial dose function and anisotropy function in water agreed well with previous literatures. The lung dose near the source, however, would be overestimated by up to 12% if water was used as the lung material. The result implies that if tumor is located in lung, the tumor dose will be overestimated if the difference in material density is not taken into consideration. The calculated results from this study could offer as a clinical reference for improving the accuracy of dose delivered for brachytherapy within the patient of lung cancer. The 2nd part explores how the metal materials of the applicator influence the dose distribution when performing brachytherapy for cervical cancer. (1) 192Ir source located at a single position: For dose distribution in water with the presence of the tandem, differences among measurement, MCNPX calculation and treatment planning system results are < 5%. For dose distribution in water with the presence of the ovoid, the MCNPX result agrees with the measurement. But the doses calculated from treatment planning system were overestimated by up to a factor of 4. This is due to the shielding effect of the metal materials in the applicator not being considered in the treatment planning system. (2) Multiple 192Ir source dwell positions: When the applicator was used in treatment, the absolute dose difference between the TLD results and the MCNPX simulation results agreed within ~ 6 %. Compared with the MCNPX results, the TPS overestimated the ICRU rectum and bladder reference dose point by 58% and 50%, respectively. This result shows that the dose distribution calculated by TPS would be affected due to the use of applicator containing metal material, which suggests that the TPS result should be modified to take into account the shielding effect of the applicator to ensure the accuracy of the dose delivery.