Dissertations / Theses: 'Cerebral arteries'

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Pierre, Lisa Natalie. "Endothelin receptors in human small coronary and cerebral arteries." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624843.

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Storer, Kingsley Paul School of Medicine UNSW. "Cerebral arteriovenous malformations: molecular biology and enhancement of radiosurgical treatment." Awarded by:University of New South Wales. School of Medicine, 2006. http://handle.unsw.edu.au/1959.4/31942.

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Object Rupture of intracranial arteriovenous malformations is a leading cause of stroke in children and young adults. Treatment options include surgery and highly focused radiation (stereotactic radiosurgery). For large and deep seated lesions, the risks of surgery may be prohibitively high, while radiosurgery has a disappointingly low efficacy and long latency. Radiosurgery carries the most promise for significant advances, however the process by which radiosurgery achieves obliteration is incompletely understood. Inflammation and thrombosis are likely to be important in the radiation response and may be amenable to pharmacological manipulation to improve radiosurgical efficacy. Materials and methods Immunohistochemistry and electron microscopy were used to study normal cerebral vessels, cavernous malformations and AVMs, some of which had previously been irradiated. An attempt was made to culture AVM endothelial cells to study the immediate response of AVM endothelium to radiosurgery. The effects of radiosurgery in a rat model of AVM were studied using immunohistochemistry and the results used to determine the choice of a pharmacological strategy to enhance the thrombotic effects of radiosurgery. Results Vascular malformations have a different endothelial inflammatory phenotype than normal cerebral vessels. Radiosurgery may cause long term changes in inflammatory molecule expression and leads to endothelial loss with exposure of pro-thrombotic molecules. Ultrastructural effects of irradiation include widespread cell loss, smooth muscle cell (SMC) proliferation and thrombosis. Endothelial culture from AVMs proved difficult due to SMC predominance in initial cultures. Radiosurgery upregulated several endothelial inflammatory molecules in the animal model and may induce pro-thrombotic cell membrane alterations. The administration of lipopolysaccharide and soluble tissue factor to rats following radiosurgery led to selective thrombosis of irradiated vessels. Conclusions Inflammation and thrombosis are important in the radiosurgical response of AVMs. Lumen obliteration appears to be mediated by proliferation of cells within the vessel wall and thrombosis. Upregulation of inflammatory molecules and perhaps disruption of the normal phospholipid asymmetry of the endothelial and SMC membranes are some of the earliest responses to radiosurgery. The alterations induced by radiation may be harnessed to selectively initiate thrombus formation. Stimulation of thrombosis may improve the efficacy of radiosurgery, increasing treatable lesion size and reducing latency.

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Corrêa, José Fernando Guedes. ""Dificuldades no tratamento microcirúrgico dos aneurismas gigantes e complexos da circulação anterior do polígono de Willis: proposta de escala técnica prognóstica"." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/5/5132/tde-27092005-145748/.

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Para desenvolver e avaliar a aplicabilidade de uma escala técnica prognostica das dificuldades no tratamento microcirúrgico dos aneurismas gigantes e complexos da circulação anterior do polígono de Willis, 50 lesões foram operadas. Um valor numérico foi dado a cada uma das 8 variáveis da escala. Somando-se os valores para cada variável, uma nota (de 1 a 14) foi obtida, para cada uma das 50 cirurgias. Dois grupos, portanto, foram definidos: cirurgia difícil (nota de 1 a 8) e cirurgia extremamente difícil (nota de 9 a 14). Foi feita análise estatística comparando-se os 2 grupos em relação a diversas variáveis demográficas e clínicas. Concluiu-se que a escala proposta é útil no planejamento pré-operatório, intra-operatório e prognóstico neste tipo de aneurisma In order to develop and verify the applicability of a technical and prognostic scale of the difficulties in the microsurgical treatment of giant and complex aneurysms of the anterior circulation of the Cicle of Willis, 50 lesions were operated. A numeric amount was given for each of 8 variants of the scale. By adding each amount for each variant a score(from 1 to 14) was achieved, for each of the 50 surgeries. Two groups, therefore, were established: difficult surgery (scores from 1 to 8) and extremely difficult surgery (scores from 9 to 14). Statistical assessment comparing both groups in relation to several demographic and clinical variants was done. It was concluded that the proposed scale is useful in preoperative, intraoperative and prognostic planning in microsurgery for this kind of aneurysms

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Almeida, Lygia Maria de. "Sistematização das artérias da base do encéfalo, distribuição e territórios das artérias cerebrais rostral, média e caudal e da artéria mesencefálica na superfície do encéfalo em jacaré do papo-amarelo (Cayman latirostris)." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/22679.

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Foram utilizados 30 encéfalos de jacaré do papo-amarelo (Cayman latirostris), injetados com látex, corado em vermelho, com objetivo de sistematizar e descrever a distribuição e territórios das artérias carótidas internas e suas principais ramificações na superfície do encéfalo. As artérias carótidas internas apresentaram uma anastomose intercarótica e a artéria oftálmica interna. Na altura da hipófise estas se dividiram num ramo rostral e num curto ramo caudal, que continuou naturalmente como artéria cerebral caudal. O ramo rostral formou a rede da artéria cerebral média, a artéria cerebral rostral e a artéria comunicante rostral. A artéria cerebral caudal antes de penetrar na fissura transversa do cérebro emitiu o Iº ramo central, e em seu interior originou a artéria diencefálica, o IIº ramo central, ramos hemisféricos occipitais e a artéria pineal. Ao abandonar a fissura, a artéria cerebral caudal, curvou-se caudodorsalmente, emergindo no pólo occipital do hemisfério cerebral, projetou-se rostralmente, sagital a fissura longitudinal do cérebro como artéria interhemisférica. Esta lançou ramos hemisféricos convexos e hemisféricos mediais para as respectivas faces dos hemisférios cerebrais, e anastomosou-se com sua homóloga contralateral formando a artéria etmoidal comum, que se dividiu nas artérias etmoidais: direita e esquerda, as quais progrediram para as cavidades nasais, vascularizando-as. O curto ramo caudal emitiu sua porção de médio calibre, que lançou as artérias mesencefálica e cerebelar ventral rostral. Esta porção do ramo caudal anastomosou-se com seu homólogo contralateral formando a artéria basilar. A artéria basilar acompanhou a fissura mediana ventral da medula oblonga, e lançou as artérias cerebelares ventrais caudais e espinhais dorsais, e abandonou a cavidade craniana como artéria espinhal ventral. A artéria mesencefálica formou as artérias tectais, cerebelar dorsal rostral e cerebelar dorsal caudal. A artéria espinhal dorsal originou a artéria trigeminal. O círculo arterial cerebral apresentou-se fechado tanto rostral como caudalmente e o suprimento sanguíneo cerebral foi feito exclusivamente pelo sistema carótico. It was utilized 30 brains of broad- snouted Cayman (Cayman latirostris), injected with red stained latex, aiming to systematize and describe the distribution and territories of the internal carotid arteries and their main branches on the surface of the brain. The internal carotid arteries showed an anastomosis intercarótica and internal ophthalmic artery. At the level of the hypophysis divided into a rostral branch and a short caudal branch, which continued naturally as caudal cerebral artery. The rostral branch formed a middle cerebral artery network, the rostral cerebral artery and the rostral communicating artery. The caudal cerebral artery before entering the cerebral transverse fissure gave of the Iº central branch and inside emitted the diencephalic artery, the IIº central branch, occipital hemispheric branches and the pineal artery. After leaving the cerebral transverse fissure, the caudal cerebral artery curved caudodorsalwards, emerging at the occipital pole of the cerebral hemisphere and projected rostrally sagittal to the cerebral longitudinal fissure, as interhemispheric artery. This gave off convex hemispheric branches and medial hemispheric branches of the same, and anastomosed with its contralateral homologous to form the common ethmoidal artery, which divided into the ethmoidal arteries: right and left, which progressed to the nasal cavities, vascularizing them. The short caudal branch gave off his portion of medium caliber, which originated the mesencephalic and ventral rostral cerebellar arteries. This portion of the caudal branch anastomosed with its contralateral homologous to form the basilar artery. The basilar artery accompanied the ventral median fissure of medulla oblongata, and emitted the ventral caudal cerebellar artery and dorsal spinal artery, and abandoned the cranial cavity as ventral spinal artery. The mesencephalic artery formed: the tectal, dorsal rostral cerebellar and dorsal caudal cerebellar arteries. The dorsal spinal artery originated a trigeminal artery. The cerebral arterial circle was rostral and caudally closed with cerebral blood supply provided, exclusively, by the carotid system.

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Hoiland, Ryan Leo. "Carbon dioxide mediated vasomotion of extra-cranial cerebral arteries : a role for prostaglandins?" Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/54108.

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Cerebrovascular regulation during perturbations in arterial CO₂ is thought to occur solely at the level of the pial vessels. However, recent evidence implicates large extra-cranial cerebral blood vessels in this regulatory process. Although the mechanisms governing CO₂ mediated vasomotion remain unclear, animal and human studies support a large role of prostaglandins. Thus, we examined two hypotheses: 1) vasomotion of the internal carotid artery (ICA) would occur in response to both hyper and hypocapnia; and 2) pharmacological inhibition of prostaglandin synthesis with Indomethacin (INDO; a non-selective cyclooxygenase inhibitor) would reduce the vasomotor response of the ICA to changes in end-tidal PCO₂ (PETCO₂). Using a randomized single-blind placebo controlled study, subjects (n=10) were tested on two occasions. Before and 90-minutes following either oral INDO (1.2mg/kg) or placebo capsule, concurrent measures of beat-by-beat blood flow, velocity and diameter of the ICA were made at rest and during steady state stages (4 min) of iso-oxic hypercapnia (+3, +6, +9mmHg above baseline) and hypocapnia (-3, -6, -9mmHg below baseline). End-tidal forcing was employed for the control of blood gases. To examine if INDO affected ICA vasomotion in a cyclooxygenase inhibition independent manner, a subset of subjects (n=5) were tested before and 45-minutes following oral Ketorolac (0.25mg/kg). During pre-drug testing in the INDO trial, the ICA dilated during hypercapnia at +6mmHg (4.72±0.45 vs. 4.95±0.51mm; P<0.001) and +9mmHg (4.72±0.45 vs. 5.12±0.47mm; P<0.001), and constricted during hypocapnia at -6mmHg (4.95±0.33 vs. 4.88±0.27mm; P<0.05) and -9mmHg (4.95±0.33 vs. 4.82±0.27mm; P<0.001). Following INDO, dilation of the ICA was still observed at +6mmHg (4.50±0.54 vs. 4.57±0.52mm; P<0.05) and +9mmHg (4.50±0.54 vs. 4.61±0.50mm; P<0.01); however, INDO reduced the vasomotor responsiveness by 67±28% (0.045±0.015 vs. 0.015±0.012mm ⋅ mmHgPETCO₂-¹). In the Ketorolac condition, there was no effect of the drug on the vasomotor response to hyper or hypocapnia. We conclude that: 1) changes in PETCO₂ mediate vasomotion of the ICA, 2) inhibition of non-selective prostaglandin synthesis via INDO markedly reduces the vasomotor response to changes in PETCO₂; and 3) INDO may be acting via a mechanism(s) independent of cyclooxygenase inhibition to reduce CO₂ mediated vasomotion. Graduate Studies, College of (Okanagan) Graduate

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Dhital, Kumud Kumar. "Perivascular innervation of cerebral arteries and vasa nervorum : changes in development and disease." Thesis, University College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322304.

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Mathewson, Alastair Munro. "The modulation of no-mediated in porcine cerebral arteries by inducible nitric oxide synthase." Thesis, University of Strathclyde, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269936.

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Mughal, Amreen. "Regulation of Vascular Tone in Cerebral and Coronary Arteries by Apelin/APJ Receptor Mechanisms." Diss., North Dakota State University, 2018. https://hdl.handle.net/10365/27847.

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The peptide, apelin, is expressed in fat cells, endothelial cells, and CNS neurons. Increasing evidence (e.g. inotropic and vasomotor effects) supports a role for apelin in the regulation of the cardiovascular system. This research aimed to understand vascular effects of apelin and bridge gaps in the knowledge about apelin-induced effects on different vascular beds i.e. cerebral and coronary arteries. My first objective was to assess apelin-induced vascular effects in cerebral arteries. Based on current data, one could conclude that apelin by itself has no effects on vasomotor tone of cerebral arteries, but it does impair nitric oxide dependent relaxations of cerebral arteries, possibly by inhibiting functions of large conductance calcium activated potassium (BKCa) channels. Apelin increases coronary blood flow; however, the involved mechanism(s) has not yet been elucidated. Hence, my next aim was to determine the mechanism(s) involved in apelin-induced vascular effects. The results suggest that apelin causes endothelium APJ receptor dependent relaxation of coronary arteries, which is possibly mediated by nitric oxide dependent direct activation of BKCa channels. Interestingly, my results also suggest that pathways involved in apelin-induced coronary arteries relaxation are markedly different from another endothelium dependent vasodilator, acetylcholine. This research is the first to report that nitric oxide, generated in response to different stimuli, can likely activate more than one signaling pathways in coronary arteries. In my final aim, I determined effects of apelin on smooth muscle BKCa channel functions in coronary arteries. My data suggest that functionally active apelin-APJ signaling has no inhibitory effects on BKCa channel functions and does not inhibit nitric oxide-induced relaxations of coronary arteries. Possible reasons for difference in apelin response between cerebral and coronary arteries could be associated with differences in activation of G-proteins and PI3K signaling pathways between these two vascular beds. Altogether, this research provides an improved understanding about apelin-induced vascular effects in cerebral and coronary arteries, and highlights some key mechanistic differences in apelin-induced vascular effects between these two blood vessels. Moreover, this knowledge may have important therapeutic implications in future design and development of apelin analogs for treatment of cardiovascular diseases. NIH National Heart, Lung and Blood Institute (HL124338)

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Miller, Alastair Leslie. "Investigation of the mechanisms underlying the myogenic response in resistance blood vessels from the rat cerebral vasculature." Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322245.

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Sutherland, Brad Alexander, and n/a. "Heme oxygenase and the use of tin protoporphyrin in hypoxia-ischaemia-induced brain damage : mechanisms of action." University of Otago. Department of Pharmacology & Toxicology, 2009. http://adt.otago.ac.nz./public/adt-NZDU20090119.150318.

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Stroke is the third largest cause of death, and the leading cause of disability worldwide. Treatments are sought to reduce mortality, and increase survival time following an ischaemic stroke. Hypoxia-ischaemia (HI) is the combination of cerebral ischaemia and global hypoxia that can lead to neuronal damage, particularly perinatally. The complex neurodegenerative cascade following ischaemic stroke and HI activates many stress pathways, including heme oxygenase (HO). HO metabolises free heme to release iron, carbon monoxide, and biliverdin, which is subsequently metabolised to bilirubin. This thesis aims to elucidate the role HO plays following HI, and assess any neuroprotective mechanisms using HO modulators. The 26 day old rat model of HI was used to induce the neurodegenerative cascade. All animals were sacrificed 3 days post-insult. Immunohistochemistry and Western blotting demonstrated that HO-1 was increased in the ipsilateral hemisphere of both HI (by 1.7 � 0.1 fold: p = 0.016, n = 4) and middle cerebral artery occlusion (MCAO) brains (by 1.6 � 0.1 fold: p = 0.037, n = 4), compared to controls. HO-2 was constitutively expressed throughout the control brain, but HI upregulated HO-2 expression (by 1.7 � 0.2 fold: p = 0.027, n = 4) ipsilaterally, whereas MCAO did not alter HO-2 expression. Administration of the HO inhibitor tin protoporphyrin (SnPP; 30[mu]mol/kg intraperitoneally) daily, beginning 1 day prior to HI until sacrifice, reduced infarct volume to 50% � 10 of saline-treated animals (p = 0.039, n = 6-8). The HO inducer ferriprotoporphyrin (FePP; 30[mu]mol/kg) had no effect on infarct volume. HO activity and protein expression were not significantly altered following treatment with SnPP. Therefore, the neuroprotective actions of SnPP may be through alternative mechanisms. SnPP treatment increased HI + saline-induced total nitric oxide synthase (NOS) activity by 1.5 � 0.06 fold (p < 0.001, n = 6-8). Conversely, SnPP inhibited both inducible NOS (50% � 7 of HI + saline; p = 0.045, n = 7-8) and cyclooxygenase (COX) activity (32% � 6 of HI + saline; p = 0.049, n = 4-8). SnPP treatment also increased mitochondrial complex I activity by 1.6 � 0.25 fold (p = 0.04, n = 4-8) and complex V activity by 1.7 � 0.26 fold (p = 0.046, n = 4-8) in the ipsilateral hemisphere. It appears that SnPP is acting on inflammatory and mitochondrial enzymes to produce neuroprotection. In vitro analysis of cultured RAW264.7 macrophages exposed to lipopolysaccharide (LPS; 10[mu]g/mL) treated with SnPP (dose range: 10⁻�⁰M - 10⁻⁵M) did not alter nitrite levels or cell viability. However, high dose SnPP (10⁻⁵M) in the absence of LPS increased nitrite levels from control cells by 2.7 � 0.7 fold (p = 0.043, n = 6), complementing the in vivo total NOS data. Other mechanisms such as NMDA receptor activation were not affected by 100[mu]M SnPP or 100[mu]M SnCl₂ in patch clamped cortical pyramidal neurons. Overall, the role that HO plays following HI remains unclear, but this thesis provides definitive evidence that SnPP (an established HO inhibitor) provides neuroprotection. This neuroprotection may be due to its effects on inducible pathways such as NOS and COX. Therefore, further experimentation is required to fully elucidate the role that HO plays following cerebral ischaemia, and additional in vivo evidence will be necessary to establish HO inhibitors as a putative candidate for cerebral ischaemia neuroprotection.

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Clark, Angela. "A study of the mechanisms involved in the responses of cerebral arteries to 5-hydroxytryptamine." Thesis, University of Southampton, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316053.

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Goltz, Laura Ver. "Sistematização, distribuição e territórios das artérias cerebrais rostral, média e caudal na superfície do encéfalo em nutria (Myocastor coypus)." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/165877.

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Foram utilizados 30 encéfalos de nutria (Myocastor coypus), injetados com látex, corado em vermelho, com objetivo de sistematizar e descrever a distribuição e territórios das artérias cerebrais rostral, média e caudal e suas ramificações na superfície dos hemisférios cerebrais e no tronco encefálico. A artéria carótida interna apresentou-se atrofiada, sendo o encéfalo vascularizado exclusivamente pelo sistema vértebro-basilar. A artéria vertebral penetrou pelo forame magno, e seus antímeros anastomosaram-se formando uma calibrosa artéria basilar. A artéria basilar, de grande calibre, alcançou o sulco rostral da ponte, dividiu-se em dois ramos terminais, em uma divergência de aproximadamente 90°, e lançou as artérias cerebelar rostral, cerebral caudal, hipofisária, corióidea rostral e ramos centrais para o lobo piriforme. Após, os ramos terminais da artéria basilar projetaram-se rostro-lateralmente até a altura da origem aparente do nervo oculomotor (III par craniano), e curvaram-se alcançando o trato óptico, lançando a artéria cerebral média e a artéria cerebral rostral, seu ramo terminal. A artéria cerebelar rostralemitiu um ramo tectal mesencefálico caudal, para a face caudal do colículo caudal. A artéria cerebral caudal, normalmente única, de grosso calibre, projetava-se látero-dorsalmente para o interior da fissura transversa do cérebro, lançando as artérias tectal mesencefálica rostral (componente proximal) e inter-hemisférica caudal. A artéria tectal mesencefálica rostral vascularizou a maior parte do tecto mesencefálico, e os ramos terminais das artérias tectais mesencefálicas, rostral e caudal, formaram uma rede anastomótica sobre a superfície dos colículos rostrais e caudais. A artéria inter-hemisférica caudal lançou ramos centrais, artérias corióidea caudal (esta anastomosava-se com a artéria corióidea rostral, vascularizando o diencéfalo e o hipocampo), hemisféricas occipitais (para o pólo occipital do hemisfério cerebral), ramos tectais mesencefálicos rostrais (componentes distais), e então contornava o esplênio do corpo caloso anastomosando-se “em ósculo” com a artéria inter-hemisférica rostral. A artéria cerebral média, de grande calibre, projetava-se pelo interior da fossa lateral do cérebro, lançando ramos centrais caudais e rostrais para o páleo-palio da região. Ela ultrapassou o sulco rinal lateral, formando um a dois eixos principais para a face convexa do hemisfério cerebral, originando ramos hemisféricos convexos caudais e rostrais, e suas ramificações terminais anastomosavam-se “em ósculo” no lobo parietal com os ramos das artérias hemisféricas mediais rostrais, ramo da artéria cerebral rostral. A artéria cerebral rostral, de grosso calibre, projetou-se rostro-medialmente, na altura do quiasma óptico, emitindo um ramo medial, para a fissura longitudinal do cérebro. Seu eixo principal projetava-se rostralmente, acompanhando a fissura longitudinal do cérebro, até o bulbo olfatório, continuando-se para a cavidade nasal como artéria etmoidal interna. Esta emitiu ramos centrais, hemisférico medial e artérias lateral e medial do bulbo olfatório. O ramo medial anastomosava-se com seu homólogo contralateral, quando presente, fechando o círculo arterial cerebral rostralmente, formando uma artéria comunicante rostral, mediana ímpar. Esta se bifurcou nas artérias inter-hemisféricas rostrais, que vascularizavam toda face medial dos hemisférios cerebrais, até o esplênio do corpo caloso, emitindo as artérias hemisférica rostral e hemisférica medial rostral, sendo que os ramos terminais desta alcançavam a face convexa, anastomosando-se com os ramos terminais da artéria cerebral média. Thirty nutria brains were used (Myocastor coypus), injected with latex and stained in red, in order to systematize and describe the distribution and the territories of the rostral, middle and caudal cerebral arteries and their ramifications in the surface of cerebral hemispheres and in the brain stem in nutria. The internal carotid artery was atrophied, being the encephalic vascularized exclusively by the vertebro-basilar system. The vertebral artery penetrated the magnum foramen, and their antimeres anastomosed to form a calibrous basilar artery. The basilar artery, of great caliber, reached the rostral sulcus of the pons, divided into two terminal branches, at a divergence of approximately 90°, and launched the rostral cerebellar, caudal cerebral, hypophyseal, rostral choroid arteries and central branches to the piriform lobe. Afterwards, the terminal branches of the basilar artery were projected rostrolaterally up to the apparent origin of the oculomotor nerve (III cranial nerve), and bent over reaching the optic tract, launching the middle cerebral artery and the rostral cerebral artery, its terminal branch. The rostral cerebellar artery emitted a caudal tectal mesencephalic branch, to the caudal surface of the caudal colliculus. The caudal cerebral artery, usually unique, of large caliber, projected laterally into the transverse fissure of the brain, launching the rostral tectal mesencephalic (proximal component) and caudal inter-hemispheric arteries. The rostral tectal mesencephalic artery vascularized most of the mesencephalic roof, and the terminal branches of the tectal mesencephalic arteries, rostral and caudal, formed an anastomotic network on the surface of rostral and caudal colliculus. The caudal inter-hemispheric artery emitted central branches, caudal choroid (this anastomosis with the rostral choroidal artery, vascularizing of the diencephalon and hippocampus), occipital hemispheres artery (to the occipital pole of the cerebral hemisphere), rostrais tectral mesencephalic branches (distal components), and then bypassed the splenius of the corpus callosum anastomosing "in osculum" with the rostral inter-hemispheric artery. The medium cerebral artery, of great caliber, projected through the interior of the cerebral lateral fossa, Releasing caudal and rostrais central branches to the paleopallio region. It crossed the lateral rinal groove, forming one to two main axes to the convex surface of the cerebral hemisphere, originating caudal and rostral convex hemispheric branches, and its terminal branches anastomosed "in osculum" in the parietal lobe with the branches of the mediais rostrais hemispherics arteries, branch of the rostral cerebral artery. The rostral cerebral artery, of large caliber, projected rostro-medially, at the level of optic chiasm, emitting a medial branch, for the cerebral longitudinal fissure. Its main axis was projected rostrally, accompanying the cerebral longitudinal fissure, until the olfactory bulb, continuing to the nasal cavity as internal ethmoidal artery. It emitted central branches, medial hemispheric and lateral and medial of the olfactory bulb arteries. The medial branch was anastomosed with its contralateral homologous, when present, closing the cerebral arterial circle rostrally, forming a rostral communicating artery, unique median. This bifurcated in the inter-hemispheric rostrais arteries, which vascularized the entire medial face of the cerebral hemispheres, until the splenius of the corpus callosum, emitting the rostral hemispherical and hemispherical medial rostral arteries, being that the terminal branches of this reached the convex surface, anastomosing with the terminal branches of the middle cerebral artery.

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Routledge, Hayden Swailes. "Regulation of myogenic tone in cerebral and mesenteric resistance arteries by metabolic agents and second messenger systems." Thesis, University of Glasgow, 2000. http://theses.gla.ac.uk/4904/.

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1. The pressure-perfusion myograph. permeabilisation techniques and also intracellular membrane potential recordings were used to examine the regulation of myogenic tone in cerebral and mesenteric resistance arteries by metabolic agents and second messenger systems. 2. After pressurisation to 60 mmHg, rat isolated mesenteric and cerebral resistance arteries developed spontaneous myogenic tone, resulting in a 26 ± 1% (n = 42) and 30 ± 2% (n = 14) reduction in diameter respectively. 3. The metabolic vasodilator adenosine and the KATI' channel opener cromakalim each produced a dose-dependent dilatation of pressurised mesenteric arteries. The cromakalim-evoked dilatation was inhibited by glibenc1amide (l J.lM), demonstrating the presence of the KATI' channel in the mesenteric artery and their activation as the mechanism for cromakalim-evoked dilatation. In contrast neither adenosine nor cromakalim produced a dilatation of pressurised cerebral arteries. 4. Adenosine-evoked dilatation of mesenteric arteries was unaffected by the nitric oxide synthase inhibitor L-NAME (100 IlM). antagonists of the KATI' channel (gJibenclamide; 1 J.lM), the small conductance Ca2' activated K+ channel (apamin; 0.3 J.lM) and the large conductance, Ca2! activated K+ channel (TEA; 1 mM). Further to this, cromakalim (10 IlM) but not adenosine (100 J.lM) produced a hyperpolarisation of the pressurised mesenteric artery. This suggests that neither nitric oxide synthesis nor K+ channel activation contributed to the adenosine-evoked dilatation. 5. Adenosine evoked adose-dependent dilatation of p-escin permeabilised mesenteric arteries; where the intracellular Ca" concentration was clamped to ~600 nM. The mechanism of adenosine-evoked dilatation may involve a decreased myofilament Ca2+ sensitivity. 6. An increase in extracellular potassium ion concentration ([K+lo) may link increased neuronal activity and regional cerebral blood flow. Elevation of [K+Jofrom 4.7 to 10 mM evoked a sustained dilatation of isolated pressurised thalamo-perforating cerebral arterioles. 7. The K+-evoked dilatation was inhibited by the inward rectifier K+ channel (K1R) inhibitor Ba2+ (50J.lM), and the K+ channel inhibitor cesium (20mM) but was not blocked by inhibitors of the ATP-sensitive (KATP)and the Ca2 + -activated K+ channel (KcJ, glibenclamide (l J.lM) and TEA (lmM) respectively. Nor was the dilatation altered with the neurotoxin tetrodotoxin (TTX, 0.3 J.lM). The K+--evoked dilatation was associated with a membrane hyperpolarisation to -58 ± I mV (n = 5), from a control value of -42 ± 1 mV (n = 10). 8. It is proposed that increased [K+Jo evokes a dilatation of thalamoperforating cerebral arteries via an activation of KIR channels and smooth muscle cell hyperpolarisation. 9. An increase in [Ca2+]o to approximately 700 nM evoked a 30 ± 3 % (n = 28) constriction of isolated ~-escin permeabilised cerebral resistance arteries. 10. Under [Ca2+1 clamped conditions the putative PKC activator indolactam evoked a 20 ± 2% constriction of the artery. The PKC inhibitor (PKC(19_ 36); I IlM) produced a near maximal (85 ± 4 %) reversal of the indolactam-evoked constriction of the artery, while PKC(19_36) (1 IlM) produced only a minor (12 ± 3 %) reversal of the Ca2+-induced constriction, thus confirming that the indolactam-evoked constriction was due to an activation ofPKC. 11. The MLCK antagonist SM-l (100 JlM) reversed both the Ca2+_ and the indolactam-evoked constriction of the artery. The calmodulin antagonist RS-20 (0.1 - 100 JlM) dose-dependently reversed the Ca2 + -evoked constriction but, even up to a concentration of 300 JlM, did not reverse the indolactam evoked-constriction of the artery. 12. It is proposed that MLCK but not calmodulin plays a role in the PKCevoked smooth muscle contraction.

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Souza, Fernanda de. "Sistematização das artérias da base do encéfalo e suas fontes de suprimento sanguíneo em coelho da raça Nova Zelândia (Oryctolagus cuniculus)." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/40082.

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Foram utilizados 30 encéfalos de coelhos Nova Zelândia (Oryctolagus cuniculus), injetados com látex, corado em vermelho, com objetivo de sistematizar as artérias da base do encéfalo e suas fontes de suprimento sanguíneo. Sistematizou-se a origem das fontes de suprimento sanguíneo para o encéfalo e as artérias (Aa) da face ventral do mesmo, tanto à direita (D) como à esquerda (E), com suas respectivas percentagens de aparecimento: o arco aórtico emitiu tronco braquiocefálico e artéria (A.) subclávia E (83,3%), ou tronco braquiocefálico, A. carótida comum E e A. subclávia E (16,7%). O tronco braquiocefálico lançou A. carótida comum D e E e A. subclávia D (83,3%), ou A. carótida comum D e A. subclávia D (16,7%). A. carótida comum dividiu-se em Aa carótidas externa e interna (96,7% D, 100% E). A. carótida interna D presente (96,7%) e ausente (3,3%), à E presente (100%). A. corióidea rostral D ramo colateral do ramo rostral da A. carótida interna D (83,3%), ramo colateral do ramo caudal da A. carótida interna D (16,7%), à E, ramo colateral do ramo rostral da A. carótida interna E (93,3%), ramo colateral do ramo caudal da A. carótida interna E (6,7%). A. cerebral média D e E ímpar (80%) e dupla (20%). A. cerebral rostral D com calibre médio (90%), calibre fino (6,7%), calibre muito fino (3,3%), à E, com calibre médio (76,7%), calibre fino (16,7%), calibre muito fino (6,7%). A. etmoidal interna ausente (73,3%), presente e ímpar (26,7%). A. cerebral caudal D, ímpar (66,7%), dupla (26,7%) e tripla (6,7%), à E, ímpar (63,3%) e dupla (36,7%). Ramos terminais das Aa. vertebrais D e E presentes (100%) formaram a A. basilar (100%). A. espinhal ventral ímpar presente (100%). A. cerebelar caudal D, ímpar (43,3%), ímpar com A. labiríntica isolada (26,7%) e dupla (30%), à E, ímpar (50%), ímpar com A. labiríntica isolada (6,7%), dupla (40%) e tripla (3,3%). A. trigeminal D e E presente (100%). A. cerebelar rostral D, ímpar (53,3%) e dupla (46,7%), à E, ímpar (63,3%) e dupla (36,7%). Observou-se que o círculo arterial cerebral do coelho foi fechado caudalmente (100%), rostralmente fechado (93,3%) e aberto (6,7%). O encéfalo foi suprido pelos sistemas vértebro-basilar e carotídeo. It was utilized 30 brains of New Zealand rabbits (Oryctolagus cuniculus), injected with red stained latex. The arteries to the blood supply’s sources and to the ventral surface of the brain were systematized, on the right (R) and on the left (L) sides, with respective percentages of appearance: the aortic arch emitted the braquicephalic trunk and the left subclavian artery (83,3%); or the braquicephalic trunk, the left common carotid artery and the left subclavian artery (16,7%). The braquicephalic trunk emitted the right and the left commons carotids arteries and the right subclavian artery (83,3%); or the right common carotid artery and the right subclavian artery (16,7%). Commons carotid arteries divided into external and internal carotids arteries (96.7% on the R, 100% on the L.). The internal carotid artery, on the R, present (96,7%) and absent (3,3%), on the L, present (100%).The rostral corioidea artery, on the R, collateral branch of rostral branch of the internal carotid artery (83,3%), collateral branch of caudal branch of the internal carotid artey (16,7%), on the L, , collateral branch of rostral branch of the internal carotid artery (93,3%), collateral branch of caudal branch of the internal carotid artey (6,7%).The middle cerebral artery, on the R and on the L, single (80%) and double (20%).The rostral cerebral artery, on the R, with middle caliber (90%), thin caliber (6,7%) and much thin caliber (3,3%), on the L, with middle caliber (76,7%), thin caliber (16,7%) and much thin caliber (6,7%).The internal ethmoidal artery single, absent (73,3%), present and single (26,7%). The caudal cerebral artery, on the R, single (66,7%), double (26,7%) and triple (6,7%), on the L, single (63,3%) and double (36,,7%). The terminal branches of the right and the left vertebral arteries present (100%) were forming the basilar artery (100%). The ventral spinal artery present (100%).The caudal cerebellar artery, on the R, single (43,3%), single with labirintic artery isolated (26,7%) and double (30%), on the L, single (50%), single with labirintic artery isolated (6,7%), double (40%) and triple (3,3%).The trigeminal artery, on the R and on the L, present (100%).The rostral cerebellar artery, on the R, single (53,3%) and double (46,7%), on the L, single (63,3%) and double (36,7%). The rabbit’s cerebral arterial circle was closed caudally (100%) and it was rostrally closed (93,3%) or open (6,7%). The brain was supplied by vertebral-basilar and carotid systems.

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Dashner, Roger A. "Visualizing the cerebral microvasculature anatomical explorations into the resolution capabilities of 8 tesla magnetic resonance imaging /." Columbus, Ohio : Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc%5fnum=osu1053533400.

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Thesis (Ph. D.)--Ohio State University, 2003. Title from first page of PDF file. Document formatted into pages; contains xviii, 105 p.; also contains graphics (some col.). Includes abstract and vita. Advisor: David L. Clark, Dept. of Anatomy. Includes bibliographical references (p. 98-105).

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Oliveira, Jean Gonçalves de. "Avaliação do fluxo sanguíneo em artérias perfurantes durante a cirurgia de aneurismas intracranianos através da video-angiografia intra-operatória utilizando indocianina verde." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/5/5138/tde-10032010-113140/.

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Introdução. As artérias perfurantes comumente são evidenciadas durante a dissecção microcirúrgica para clipagem de aneurismas intracranianos. A oclusão de artérias perfurantes pode ser responsável por infarto encefálico isquêmico e resultados clínicos indesejáveis. O presente estudo objetiva descrever a utilidade da vídeo-angiografia intra-operatória com indocianina verde (VAIICG) na avaliação do fluxo sanguíneo em artérias perfurantes visibilizadas no campo microcirúrgico, durante a clipagem de aneurismas intracranianos. Secundariamente, foi analisada a incidência de artérias perfurantes envolvidas durante a cirurgia de aneurismas intracranianos, e a ocorrência de infarto encefálico isquêmico causado pelo comprometimento das artérias perfurantes. Método. Sessenta pacientes, com 64 aneurismas intracranianos foram tratados cirurgicamente, e prospectivamente incluídos neste estudo. A VAIICG intra-operatória foi realizada com o uso de microscópio neurocirúrgico (Carl Zeiss Co. Oberkochen, Germany) com a tecnologia VAIICG integrada. A presença e o envolvimento de artérias perfurantes foram analisados no campo microcirúrgico durante a dissecção cirúrgica, e durante a clipagem do aneurisma. A patência vascular após a clipagem também foi investigada. Apenas artérias pequenas que não foram visibilizadas nas imagens pré-operatórias de angiografia digital com subtração (ADS) foram consideradas para análise. Resultados. A VAIICG permitiu a visibilização do fluxo sanguíneo em todos os casos que apresentaram artérias perfurantes no campo microcirúrgico. Dentre 36 casos cujas artérias perfurantes estavam visíveis à VAIICG, 11 casos (30,5%) apresentaram relação próxima entre o aneurisma e artérias perfurantes. Em um paciente (9,0%), dentre os 11 casos com relação próxima, a VAIICG evidenciou oclusão de uma artéria perfurante de P1 após a aplicação do clipe, cujo reposicionamento correto restabeleceu imediatamente o fluxo sanguíneo, o qual foi visibilizado com a VAIICG, sem conseqüências clínicas. Quatro pacientes (6,7%) apresentaram infarto pós-operatório em território de artérias perfurantes, sendo que em três deles, as artérias perfurantes estavam ausentes ou distantes do aneurisma clipado. Conclusão. O envolvimento de artérias perfurantes durante a clipagem microcirúrgica de aneurismas intracranianos é comum. A VAIICG intra-operatória fornece informação visual do fluxo sanguíneo em artérias de calibre milimétrico, e seu uso possibilita evitar a oclusão de artérias perfurantes e subseqüente infarto encefálico. Background. Perforating arteries are commonly involved during the surgical dissection and clipping of intracranial aneurysms. Occlusion of perforating arteries may be responsible for ischemic infarction and poor outcome. The goal of this study was to describe the usefulness of near-infrared indocyanine green videoangiography (ICGA) for the intraoperative assessment of blood flow in perforating arteries that are visible in the surgical field during clipping of intracranial aneurysms. In addition we analyzed the incidence of perforating vessels involved during the aneurysms surgery and the incidence of ischemic infarct caused by compromising of these small arteries. Method. Sixty patients harboring 64 aneurysms were surgically treated and prospectively included in this study. Intraoperative ICGA was performed using a surgical microscope (Carl Zeiss Co. Oberkochen, Germany) with integrated ICGA technology. The presence and involvement of perforating arteries was analyzed in the microsurgical field, during surgical dissection, and during the clip application. Assessment of vascular patency after clipping was also investigated. Only those small arteries that were not visible on preoperative digital subtraction angiography (DSA) were considered for analysis. Results. In all cases in which perforating vessels were found in the microscope field, the ICGA was able to visualize flow. Among 36 cases whose perforating vessels were visible on ICGA, 11 cases (30,5%) presented a close relation between the aneurysm and perforating arteries. In one patient (9,0%), among these 11 cases with close relation, ICGA showed occlusion of a P1 perforating artery after clip application, which led to immediate correction of the clip confirmed by immediate re-establishment of flow visible with ICGA without clinical consequences. Four patients (6,7%) presented with postoperative perforating artery infarct of whom in 3 patients the perforating arteries were either not visible or distant from the aneurysm. Conclusion. The involvement of perforating arteries during clip application for aneurysm occlusion is a usual finding. Intraoperative ICGA provide visual information with regard to patency of these milimetric vessels, which may avoid their occlusion and further ischemic infarction.

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Sugita, Kenichiro, Masato Shibuya, Masakazu Takayasu, Yasukazu Kajita, Shin-ichi Satoh, Yoshio Suzuki, and Hirofumi Oyama. "Role of Nitric Oxide in the Cerebral Vasodilatory Responses to Vasopressin and Oxytocin in Dogs." Thesis, Nature Publishing Group, 1993. http://hdl.handle.net/2237/16711.

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Rand, Victoria. "A study of the influence of the endothelium on the responses of the smooth muscle cells in rabbit cerebral arteries." Thesis, University of Southampton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316423.

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ITOH, JUNKI, SOHSHUN TAKADA, HITOSHI ISHIGURI, and HIROJI KUCHIWAKI. "Patterns of Regional Cerebral Blood Flow in Patients with Occlusive or Stenotic Lesions of Both the Internal Carotid and Vertebrobasilar Arteries." Nagoya University School of Medicine, 1988. http://hdl.handle.net/2237/17504.

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Hollnagel, Dorothea Ilse. "Hemodynamics in cerebral arteries and aneurysms : comparative velocity investigations with 3D phase-contrast magnetic resonance angiography, laser doppler velocimetry and computational fluid dynamics." Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17658.

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21

Belik, Fernanda Stringuetta. "Influência do treinamento aeróbico intradialítico no fluxo sanguíneo cerebral e o reflexo sobre a função cognitiva e qualidade de vida em pacientes renais crônicos." Botucatu, 2016. http://hdl.handle.net/11449/136474.

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Orientador: Roberto Jorge da Silva Franco Resumo: Introdução: A doença renal crônica (DRC) tem uma inter-relação complexa com outras doenças. A literatura relata a associação direta entre declínio da função renal e comprometimento cognitivo, o qual está relacionado com pior qualidade de vida (QV). Alterações na hemodinâmica cerebral podem desempenhar papel relevante na patogenia da disfunção cognitiva entre pacientes em hemodiálise (HD). Recentemente, surgiram evidências que apoiam o papel da atividade física na prevenção ou no adiamento do declínio cognitivo. Objetivo: Avaliar os efeitos do treinamento aeróbico intradialítico sobre o fluxo sanguíneo cerebral, função cognitiva e QV em pacientes com DRC que realizam HD. Casuística e Métodos: Estudo clínico controlado e randomizado de intervenção fisioterápica, com análise de intenção de tratar. Trinta pacientes foram submetidos a teste ergométrico, avaliação do fluxo sanguíneo cerebral, avaliação da rigidez arterial, teste de função cognitiva e questionário de QV. O grupo de intervenção (GI), com quinze pacientes, foi submetido a treinamento aeróbico intradialítico, três vezes por semana, durante quatro meses. O grupo controle (GC), com quinze pacientes, não teve intervenção. Todos os pacientes foram reavaliados após o término do protocolo de atividade física ou após quatro meses da primeira avaliação, para o grupo controle. Resultados: No GI, os resultados mostraram melhora estatisticamente significante da função cognitiva (p<0,001), velocidade máxima do fluxo sanguíneo da a... (Resumo completo, clicar acesso eletrônico abaixo) Abstract: Introduction: Chronic kidney disease (CKD) has a complex interrelationship with other diseases. The literature reports a direct association between decline in kidney function and cognitive impairment, which is associated with worse quality of life (QoL). Changes in cerebral hemodynamics may play a role in the pathogenesis of cognitive impairment among patients on hemodialysis (HD). Recently, there is evidence to support the physical activity role in preventing or delaying cognitive decline. Objective: To evaluate the effects of intradialytic aerobic training on cerebral blood flow, cognitive function and QoL in patients with CKD in HD. Methods: randomized controlled trial of physiotherapy intervention, with analysis intention to treat. Thirty patients underwent exercise testing, evaluation of cerebral blood flow, arterial stiffness, cognitive function test and QoL questionnaire. Fifteen patients in intervention group (IG) underwent intradialytic aerobic exercise three times a week for four months. Others fifteen patients in control group (CG) had no intervention. All patients were reassessed after the physical activity protocol or four months after the first evoluation, for the control group. Results: In IG, results showed statistically significant improvement of cognitive function (p <0.001), maximum blood flow velocity of the basilar artery (p = 0.029) and QoL in the fields dialysis staff encouragement (p = 0.025) and pain (p = 0.008). The variable arterial stiffness was no... (Complete abstract click electronic access below) Doutor

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Leão, Karina Ferreira. "DESEMPENHO COGNITIVO DE PESSOAS COM ACIDENTE VASCULAR ENCEFÁLICO." Pontifícia Universidade Católica de Goiás, 2015. http://localhost:8080/tede/handle/tede/1878.

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Made available in DSpace on 2016-07-27T14:20:39Z (GMT). No. of bitstreams: 1 KARINA FERREIRA LEAO.pdf: 931734 bytes, checksum: d9ac2b2c89cc1041418e8622e328e625 (MD5) Previous issue date: 2015-02-26 Recent studies reveal the high frequency of individuals who are affected by stroke and the cognitive dysfunctions they feature consequently. This paper seeks to assess the cognitive impairments of experiencing a stroke and, more specifically, to evaluate the cognitive performance of people affected by stroke according to hemisphere and artery affected. The paper is divided into two main parts. At first, a theoretical review about the neuropsychological impairments in individuals with stroke was made with the goal of understanding the relationship between brain areas and the cognitive performance of these individuals. For this, a bibliographical survey was conducted in major databases on this subject, describing the theoretical aspects related to Neuroscience, stroke and resulting cognitive dysfunctions assessed by neuropsychological avaliation. It has been found that, as for the etiological description, identification of the types and anatomical structures altered, there is a wide literature, but in relation to cognitive impairment and specific brain areas of research conducted in the field of neurophysiology there is a paucity of publications. Research indicates that it is of fundamental importance more studies intending to show, more and more, the cognitive difficulties in people afflicted with a disease so common in society. Then, in Part 2, an empirical study was conducted with the objective of evaluating the cognitive performance according to hemisphere and artery affected in different neuropsychological tests. Participated in the study 30 patients with a diagnosis of stroke, with the age group between 24-60 years. According to the data, we observe a significant difference according to the lesioned hemisphere only in alternation skills, auditory span, visual-construction, lexical and semantic verbal fluency and verbal comprehension. Regarding to the affected arteries, significant differences were found in selective attention, abstraction, naming, phonetic verbal fluency, verbal comprehension, visual-constructional praxis and recognition of the mnemonic process. The present study as well as providing an understanding of neuropsychological and cognitive impairments of patients injured by stroke, can assist in the development of neuropsychological assessment batteries for people affected by stroke and rehabilitation strategies from possibilities of cognitive dysfunctions according to compromised region after stroke. In general, the two parts of the dissertation contribute to the theoretical extension about cognitive dysfunctions of patients suffering from stroke and consequently the identification of these dysfunctions may thus help to improve care for patients with this disease. Estudos recentes revelam a alta frequência de indivíduos acometidos por acidente vascular encefálico (AVE) e as disfunções cognitivas que se apresentam em consequência. Esta dissertação buscou avaliar as disfunções cognitivas derivadas da vivência de um AVE e, de forma mais específica, avaliar o desempenho cognitivo de pessoas acometidas por AVE em virtude do hemisfério lesionado e da artéria afetada. A dissertação está dividida em duas partes. Em um primeiro momento, foi realizada uma revisão teórica sobre as alterações neuropsicológicas em indivíduos com AVE, com o objetivo de compreender as relações entre áreas cerebrais e desempenho cognitivo desses indivíduos. Para tanto, foi realizado um levantamento bibliográfico nas principais bases de dados sobre esse tema, com o objetivo de descrever os aspectos teóricos relacionados à Neurociência, o AVE e as decorrentes disfunções cognitivas mediante avaliação neuropsicológica. Verificou-se que, em referência à descrição etiológica, identificação dos tipos e a estruturas anatômicas alteradas, existe uma ampla literatura, porém, em relação a disfunções cognitivas e áreas cerebrais específicas há uma escassez de publicação na área da neuropsicologia. As pesquisas apontam que é de mais fundamental relevância estudos que se proponham a evidenciar cada vez mais as dificuldades cognitivas em pessoas acometidas com uma doença tão frequente na sociedade. Na parte 2, foi realizado um estudo empírico, com o objetivo de avaliar o desempenho cognitivo segundo hemisfério e artéria afetada em diferentes testes neuropsicológicos. Participaram da pesquisa 30 pacientes com diagnóstico médico de AVE, na faixa etária entre 24 e 60 anos. De acordo com os dados, observouse diferença significativa quanto ao hemisfério lesionado nas habilidades de alternância, span auditivo, visuoconstrução, fluência verbal léxica e semântica e compreensão verbal. No que se refere às artérias afetadas, foram encontradas diferenças significativas nas atividades de atenção seletiva, abstração, nomeação, fluência verbal fonética, compreensão verbal, praxia visuoconstrutiva e reconhecimento do processo mnemônico. O presente estudo, além de proporcionar a compreensão de alterações neuropsicológicas e cognitivas dos pacientes lesionados pelo AVE, pode auxiliar o desenvolvimento de baterias de avaliação neuropsicológica para pessoas acometidas por essa doença, bem como estratégias de reabilitação, conforme possibilidades de disfunções cognitivas na região comprometida após a ocorrência do AVE. De maneira geral, as duas partes da dissertação contribuem para a ampliação teórica sobre as disfunções cognitivas de pacientes acometidos por AVE e, consequentemente, para identificação desses comprometimentos, podendo assim auxiliar o atendimento a pacientes com essa enfermidade.

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Belik, Fernanda Stringuetta [UNESP]. "Influência do treinamento aeróbico intradialítico no fluxo sanguíneo cerebral e o reflexo sobre a função cognitiva e qualidade de vida em pacientes renais crônicos." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/136474.

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Submitted by FERNANDA STRINGUETTA BELIK null (ferstringuetta@hotmail.com) on 2016-03-30T18:23:04Z No. of bitstreams: 1 TESE FERNANDA STRINGUETTA BELIK.pdf: 1988238 bytes, checksum: c1ee7222d5475f972cf5f72824d33f17 (MD5) Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-03-31T13:57:19Z (GMT) No. of bitstreams: 1 belik_fs_dr_bot.pdf: 1988238 bytes, checksum: c1ee7222d5475f972cf5f72824d33f17 (MD5) Made available in DSpace on 2016-03-31T13:57:19Z (GMT). No. of bitstreams: 1 belik_fs_dr_bot.pdf: 1988238 bytes, checksum: c1ee7222d5475f972cf5f72824d33f17 (MD5) Previous issue date: 2016-02-19 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Introdução: A doença renal crônica (DRC) tem uma inter-relação complexa com outras doenças. A literatura relata a associação direta entre declínio da função renal e comprometimento cognitivo, o qual está relacionado com pior qualidade de vida (QV). Alterações na hemodinâmica cerebral podem desempenhar papel relevante na patogenia da disfunção cognitiva entre pacientes em hemodiálise (HD). Recentemente, surgiram evidências que apoiam o papel da atividade física na prevenção ou no adiamento do declínio cognitivo. Objetivo: Avaliar os efeitos do treinamento aeróbico intradialítico sobre o fluxo sanguíneo cerebral, função cognitiva e QV em pacientes com DRC que realizam HD. Casuística e Métodos: Estudo clínico controlado e randomizado de intervenção fisioterápica, com análise de intenção de tratar. Trinta pacientes foram submetidos a teste ergométrico, avaliação do fluxo sanguíneo cerebral, avaliação da rigidez arterial, teste de função cognitiva e questionário de QV. O grupo de intervenção (GI), com quinze pacientes, foi submetido a treinamento aeróbico intradialítico, três vezes por semana, durante quatro meses. O grupo controle (GC), com quinze pacientes, não teve intervenção. Todos os pacientes foram reavaliados após o término do protocolo de atividade física ou após quatro meses da primeira avaliação, para o grupo controle. Resultados: No GI, os resultados mostraram melhora estatisticamente significante da função cognitiva (p<0,001), velocidade máxima do fluxo sanguíneo da artéria basilar (p=0,029) e da QV nos domínios estímulo da equipe de diálise (p=0,025) e dor (p=0,008). A variável rigidez arterial não apresentou diferença estatisticamente significante após a intervenção. A proporção de artérias que apresentaram aumento da velocidade máxima e média do fluxo sanguíneo cerebral obteve diferença estatisticamente significante entre os grupos (p=0,002 e p= 0,038 respectivamente). Conclusão: O exercício aeróbico intradialítico se mostrou benéfico para a melhora da função cognitiva e QV dos pacientes com DRC em HD. O protocolo de treinamento físico teve um efeito positivo no fluxo sanguíneo cerebral, com aumento numérico das velocidades máximas e médias da maioria expressiva das artérias avaliadas, sugerindo um possível mecanismo de melhora da função cognitiva. Introduction: Chronic kidney disease (CKD) has a complex interrelationship with other diseases. The literature reports a direct association between decline in kidney function and cognitive impairment, which is associated with worse quality of life (QoL). Changes in cerebral hemodynamics may play a role in the pathogenesis of cognitive impairment among patients on hemodialysis (HD). Recently, there is evidence to support the physical activity role in preventing or delaying cognitive decline. Objective: To evaluate the effects of intradialytic aerobic training on cerebral blood flow, cognitive function and QoL in patients with CKD in HD. Methods: randomized controlled trial of physiotherapy intervention, with analysis intention to treat. Thirty patients underwent exercise testing, evaluation of cerebral blood flow, arterial stiffness, cognitive function test and QoL questionnaire. Fifteen patients in intervention group (IG) underwent intradialytic aerobic exercise three times a week for four months. Others fifteen patients in control group (CG) had no intervention. All patients were reassessed after the physical activity protocol or four months after the first evoluation, for the control group. Results: In IG, results showed statistically significant improvement of cognitive function (p <0.001), maximum blood flow velocity of the basilar artery (p = 0.029) and QoL in the fields dialysis staff encouragement (p = 0.025) and pain (p = 0.008). The variable arterial stiffness was no statistically significant difference after intervention. The proportion of arteries which increased the maximum speed and average cerebral blood flow showed a statistically significant difference between groups (p = 0.002 and p = 0.038 respectively). Conclusion: Intradialytic aerobic exercise proved beneficial for the improvement of cognitive function and QoL of patients with CKD in HD. Physical training protocol had a positive effect on cerebral blood flow with numerical increase of the maximum and average speeds of the large majority of the evaluated arteries, suggesting a possible mechanism of improved cognitive function. FAPESP: 2011/20652-7

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Nelson, Merlisa Claudia. "Ultrasound evaluation of the extracranial cerebrospinal venous system and carotid arteries in patients with multiple sclerosis." Thesis, Cape Peninsula University of Technology, 2013. http://hdl.handle.net/20.500.11838/1565.

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Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Radiography in the Faculty of Health and Wellness Sciences at the Cape Peninsula University of Technology Supervisor: Ms. Ferial Isaacs Co-supervisor: Prof. Susan J. Van Rensburg Bellville September 2013 Multiple Sclerosis (MS) is characterised by demyelination within the central nervous system (CNS), which may result in neurological disabilities over time, causing considerable hardship to patients and their families, in addition to being costly to treat. Recent studies have linked MS to impaired cerebral blood flow, called chronic cerebrospinal venous insufficiency (CCSVI). Anecdotal evidence has suggested that surgical correction thereof results in improvement of symptoms experienced by MS patients. To my knowledge, no information is available in the literature on carotid artery disease in MS. The USA National MS Society has therefore called for more research to be done in this area. This cross-sectional observational sub-study will determine, by ultrasound (B-Mode, Colour and Pulsed-wave Doppler), the prevalence of chronic venous insufficiency (CCSVI) and carotid artery disease in the selected sample of MS patients within the region of the Western Cape, South Africa. Biochemical data; lifestyle factors such as physical activity and smoking; and nutritional status of MS patients were determined from the main study entitled: “The development of a comprehensive gene-based, pathology supported intervention program for improved quality of life in patients diagnosed with multiple sclerosis” (Division of Chemical Pathology, NHLS, Tygerberg Hospital, and University of Stellenbosch). Twenty-nine (29) patients were aged between 28-64years and they suffered from MS for 0.83-27years. A larger proximal and mid cross-sectional diameter (CSD) of the right IJV compared to the left (differences significant, P= 0.026 and P=0.023) was demonstrated. Increased intima media thickness (IMT) was present in 13.33% of the non-smoking MS group and 20% in the smoking MS group. IJV reflux was evident in 13.33% of the MS group. A significant reduction of cross-sectional diameters of the IJV’s was evident in smoking MS patients; suggesting that smoking is not only a risk factor for atherosclerotic disease but could also be related to narrowing of the major neck veins. This study also supports findings of other studies viz that there’s no significant correlation between extracranial venous abnormalities and MS. Early carotid artery disease was noted in smoking and non-smoking MS patients, however the findings were non-significant.

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Niigaki, Juliana Ikeda. "Dopplervelocimetria da artéria cerebral média fetal na predição da acidemia no nascimento em gestações com insuficiência placentária." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/5/5139/tde-08042014-090931/.

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Objetivo: Avaliar a relação das alterações de fluxo na artéria cerebral média (ACM) com a ocorrência de acidemia no nascimento, em gestações com insuficiência placentária. Métodos: estudo transversal prospectivo com 91 gestações com diagnóstico de insuficiência placentária pelo Doppler de artéria umbilical (AU) alterado (índice de pulsatilidade [IP] > p95). Os critérios de inclusão foram: gestações únicas com idade gestacional (IG) superior a 26 semanas completas, membranas ovulares íntegras, ausência de anomalias cromossômicas ou congênitas. Os parâmetros da dopplervelocimetria analisados foram: IP da AU, IP da ACM, pico de velocidade sistólica (PVS) da ACM, relação cerebroplacentária (RCP) e índice de pulsatilidade para veias (IPV) do ducto venoso (DV). Foi analisada a última avaliação fetal realizada imediatamente antes do parto ou anterior à corticoterapia. Todos os parâmetros foram analisados por meio do escore zeta ou múltiplos da mediana (MoM), baseados nas médias, desvio-padrão e valores de referência para cada IG. Imediatamente após o parto, uma amostra de sangue da artéria umbilical foi obtida para a medida do pH, e os casos classificados de acordo com a presença (pH < 7,20) ou ausência de acidemia no nascimento. Resultados: Quarenta e sete (51,6%) recémnascidos apresentaram acidemia no nascimento. Os fetos que evoluíram com acidemia apresentaram valor de escore zeta do IP da AU significativamente maior (mediana 2,1 vs 1,7; p=0,014), assim como maior proporção de casos com diástole zero ou reversa (51,0% vs 31,8%; p=0,006). Quanto à ACM, o escore zeta mostrou-se significativamente menor nos casos com pH < 7,20 (mediana -2,7 vs -2,1; p=0,042), porém, em relação ao PVS não foi possível estabelecer diferença significativa entre os grupos (p=0,051). A acidemia no nascimento se associou a menores valores de RCP (mediana 0,5 vs 0,7; p=0,006), porém não ao seu escore zeta (p=0,055). Em relação ao território venoso, maiores valores do escore zeta do IPV do DV associaram-se à acidemia (mediana 2,4 vs 0,6; p=0,015). Na análise de correlação entre os valores de pH no nascimento e os resultados da avaliação da dopplervelocimetria fetal, foi constatada correlação significativa entre o valor do pH no nascimento e o escore zeta do IP da AU (rho=-0,31; p=0,003), IP da ACM (rho=0,26; p=0,012), da RCP (rho 0,25; p=0,015) e IPV do DV (rho=-0,32; p=0,002), e PVS da ACM MoM (rho=-0,21; p=0,042). A regressão logística identificou o escore zeta do IP da AU e escore zeta IP da ACM como variáveis independentes para a predição de acidemia no nascimento, classificando corretamente 67,03% dos casos. Conclusão: em casos de insuficiência placentária, o IP da AU e da ACM são preditores independentes associados com a acidemia no nascimento. Este estudo reforça que o grau de insuficiência placentária e a capacidade de adaptação fetal estão diretamente relacionados com a acidemia no nascimento Objectives: To evaluate the relationship between middle cerebral artery (MCA) parameters and acidemia at birth, in pregnancies complicated by placental insufficiency. Methods: The study was performed as a prospective cross-sectional analysis of Doppler measurements in 91 patients with the diagnosis of placental dysfunction by abnormal umbilical artery (UA) Doppler (pulsatility index [PI] > p95). Inclusion criteria were: singleton pregnancy, intact membranes, abscence of fetal congenital or chromosomal abnormalities. The Doppler parameters analyzed were: UA PI, MCA PI, MCA peak systolic velocity (PSV), cerebroplacental ratio (CPR) and pulsatilility index for veins (PIV) of ductus venosus (DV). It was analyzed the last assessment obtained right before birth or the antenatal steroids. Umbical artey blood samples were collected at birth, and acidemia was defined as pH below 7.20. Results: Forty seven (51.6%) newborns had acidemia at birth. Those who developed acidemia showed a UA PI z-score significantly higher (median 2.1 vs 1.7, p = 0.014), as well as a higher proportion of cases with absent or reverse end diastolic flow (51.0% vs 31.8%, p = 0.006). Regarding the MAC, the PI z-score was significantly lower in cases with pH < 7.20 (median -2.7 vs. -2.1, p = 0.042), but concerning PSV z-score, no significant relation between the groups could be established (p = 0.051).The acidemia at birth was associated with lower values of CPR (median 0.5 vs 0.7, p = 0.006), but not with its z-score (p = 0.055). In relation to the venous territory, greater values of DV PIV z-score were associated with acidemia (median 2.4 vs 0.6, p = 0.015).The correlation analysis between the pH values at birth and the Doppler measurements, a significant correlation was observed between the pH at birth and UA PI z-score (rho = -0.31, p = 0.003 ), MCA PI z-score (rho = 0.26, p = 0.012), CPR z-score (rho 0.25, p = 0.015), PIV DV zscore (rho = -0.32, p = 0.002), and PSV MCA MoM (rho = -0.21, p = 0.042). Logistic regression identified the UA PI z-score and the MCA PI z-score as independent predictors for acidemia at birth, correctly classifying 67.03% of cases. Conclusion: In pregnancies with placental insufficiency, the UA PI and the MCA PI are independent predictors associated with acidemia at birth. This study reinforces that the degree of placental insufficiency and the fetal adaptation capacity are directly related to acidemia at birth

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Georgeon, Chartier Carole. "Evaluation des effets du vieillissement sur la signalisation calcique des cellules musculaires lisses des artères cérébrales dans les modèles murins C57BL6/J, SAMR1 et SAMP8 dans des conditions normales et sous restriction calorique." Thesis, Bordeaux 1, 2012. http://www.theses.fr/2012BOR14692/document.

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Au cours du vieillissement, les artères cérébrales subissent des modifications structurelles et fonctionnelles, notamment au niveau des cellules musculaires lisses (CML). La CML a pour rôle de maintenir la réactivité vasculaire via une signalisation calcique qui fait intervenir différents acteurs pouvant ainsi réguler deux phénomènes : la contraction et la relaxation. Ces acteurs rassemblent, au sein d’une même cellule, des canaux (CCVD, RYR, IP3R), des pompes calciques (SERCA, PMCA, NCX, STIM/ORAI) et leurs régulateurs (PLB, FKBP12.6, TRPP2, SARAF, TRIC). La restriction calorique (RC), apparaît comme étant un facteur retardant le vieillissement et ses pathologies. Notre travail s’est donc fortement impliqué dans l’étude de la signalisation calcique de la CML, en se focalisant sur les altérations génomiques et fonctionnelles au cours du vieillissement des artères cérébrales chez la souris C57Bl6/j. Nous avons ainsi pu mettre en évidence une altération de la signalisation calcique qui passe en partie par une modulation des niveaux d’expressions génique et protéique des canaux et pompes calciques impliqués dans ce phénomène, et par une modification fonctionnelle en termes de signaux calciques et de contraction. Après 5 mois de régime RC, il a été mis en évidence un ralentissement des altérations de la signalisation calcique liées au vieillissement et une diminution de l’oxydation des CML During aging, cerebral arteries undergo structural and functional changes, particularly in smooth muscle cells (SMC). SMC is responsible for maintaining vascular reactivity via calcium signaling involving different actors and can regulate two phenomena: contraction and relaxation. These actors regroup channels (CCVD, RYR, IP3R) calcium pumps (SERCA, PMCA, NCX, STIM / ORAI) and their regulators (PLB, FKBP12.6, TRPP2, SARAF, TRIC). Caloric restriction (CR) appears as a factor in delaying aging and its pathologies. Our work is strongly involved in the study of calcium signaling in SMC, focusing on genomic and functional alterations during aging of cerebral arteries in mice C57BL6/J. We were able to demonstrate an altered calcium signaling, which is partly through modulation of gene and protein expression levels of calcium channels and pumps involved in this phenomenon, and a functional change in terms of calcium signals and contraction. After 5 months under RC, it was highlighted a slow calcium signaling alterations associated with aging and a decrease of SMC oxidation by SAMP8

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FERNANDES, MARQUES ANTONIO ALBERTO. "Les infarctus de l'artere cerebrale posterieure : elements pronostiques ; a propos de 81 observations." Besançon, 1996. http://www.theses.fr/1996BESA3066.

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Faye, Laurence. "Infarctus de l'artere cerebrale moyenne : devenir tardif de 46 patients ; recherche de facteurs pronostiques de l'evolution tardive." Lille 2, 1994. http://www.theses.fr/1994LIL2M148.

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Haddad, Antonio Carlos. "Relações topograficas da arteria cerebral medica com o sulco lateral (de Sylvius) : (contribuição a via de acesso transsilviana aos aneurismas cerebrais da "circulção anterior")." [s.n.], 1994. http://repositorio.unicamp.br/jspui/handle/REPOSIP/309846.

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Orientador: Vilma Cloris de Carvalho Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas Made available in DSpace on 2018-07-19T18:24:16Z (GMT). No. of bitstreams: 1 Haddad_AntonioCarlos_M.pdf: 5286191 bytes, checksum: 5c4184688fd33b18f0cff0e4c15aca8d (MD5) Previous issue date: 1994 Resumo: A anatomia da artéria cerebral média e, dos giros que compõem o sulco lateral, foi estudada em 30 encéfalos não fixados. As dissecções eram feitas a partir da junção opercular fronto-temporal, de forma semelhante às abordagens transsilvianas aos aneurismas da "circulação anterior" do cérebro. Foram estudados os lados direito e esquerdo, totalizando 60 artérias e respectivos sulcos laterais. As medidas foram realizadas com paquímetro de precisão milimétrica. Foi realizada análise estatística para comparar os resul tados em relação aos lados, à idade, sexo e etnia, com nível de significância de 0,05. (...continue) Abstract: The author has studied the middle cerebral artery and the circumvolutions of the lateral fissure in thirty brains. The dissecation started at the leveI of front-temporal opercular junction similar to the transsylvian approach to the anterior circulation aneurysms. It has been studied the left and right sides in a total amount of sixty arteries and lateral fissures. The measurements were done with callipers (millimeter accurate length and diameter). A statistical analysis was done in order to compare the results among the different sides, ages, sexes and' etnic groups (P = 0.05). (¿continue) Mestrado Neurociencias Mestre em Fisiopatologia Médica

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Hérard, Alain. "L'arterite post-radique des vaisseaux a destinee cerebrale : etude de 12 cas." Angers, 1992. http://www.theses.fr/1992ANGE1034.

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López, Diestra Jefferson. "Cuantificación de la arteria cerebral media hiperdensa, en pacientes con accidente cerebrovascular isquémico agudo, atendidos en el servicio de tomografía del Hospital Nacional Hipólito Unanue. Mayo – diciembre 2014, Lima – Perú." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2015. https://hdl.handle.net/20.500.12672/5021.

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La realización de una tomografía espiral multicorte urgente y la detección de signos precoces de isquemia: como la arteria cerebral media hiperdensa, permiten mejorar el diagnóstico, ajustar el tratamiento, evitar errores terapéuticos graves, informar sobre el pronóstico vital de los pacientes e influye significativamente en la elección del destino de estos. Por ello se busca obtener una cuantificación absoluta y relativa de la densidad en el signo de la arteria cerebral media (ACM) con la finalidad de lograr un valor objetivo para el diagnóstico temprano de isquemia cerebral aguda mediante una tomografía multicorte. Para esto se incluyeron 80 pacientes, 40 con diagnóstico presuntivo de accidente cerebrovascular (ACV) isquémico agudo (edad media 76.9 años) y 40 pacientes controles (edad media 70.1 años), atendidos en el Hospital Nacional Hipólito Unanue y que se realizaron una tomografía cerebral sin contraste con un equipo de 16 filas de detectores. Se realiza la cuantificación absoluta midiendo la densidad en unidades Hounsfield (UH) en el segmento de la ACM visualmente de mayor densidad. También se mide la densidad en el mismo segmento de la ACM contralateral para calcular la diferencia entre ambas arterias, cuantificación relativa. En los pacientes casos, la densidad media de la ACM afectada 53,65 UH (IC 95%: 52,16 a 55,13) es mayor que la de la ACM contralateral 39,24 UH (IC 95%: 38,05 a 40,43) y también es mayor en comparación con la ACM en pacientes controles 41,37 UH (IC 95%: 40,83 a 41,91) (p=0,001). En la cuantificación relativa, la diferencia media entre la densidad de la ACM afectada y la de ACM contralateral en los pacientes casos es de 14,40 UH (IC 95%: 13,29 a 15,51), mientras que en los pacientes controles, la diferencia media entre la densidad de la ACM derecha y la ACM izquierda es 3,64 UH (IC 95%: 3,20 a 4,10). Por lo que se concluye que existen diferencias significativas en la cuantificación absoluta y relativa de la densidad de la ACM en pacientes con ACV isquémico agudo, en comparación con sujetos normales. Tesis

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Torrens, Jurin Pedro Antonio. "Ecuaciones Constitutivas y Análisis Geométrico-Mecánico para Pared Arterial de Aneurismas Cerebrales y Arterias Sanas." Tesis, Universidad de Chile, 2007. http://www.repositorio.uchile.cl/handle/2250/104624.

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Helps, Stephen. "Pathophysiological basis of cerebral arterial air embolism /." Title page, table of contents and summary only, 1994. http://web4.library.adelaide.edu.au/theses/09PH/09phh484.pdf.

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von, Sarnowski Bettina, Ulf Schminke, Ulrike Grittner, Franz Fazekas, Christian Tanislav, Manfred Kaps, Turgut Tatlisumak, et al. "Cervical Artery Dissection in Young Adults in the Stroke in Young Fabry Patients (sifap1) Study." Karger, 2015. https://tud.qucosa.de/id/qucosa%3A70584.

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Background: Patients with carotid artery dissection (CAD) have been reported to have different vascular risk factor profiles and clinical outcomes to those with vertebral artery dissection (VAD). However, there are limited data from recent, large international studies comparing risk factors and clinical features in patients with cervical artery dissection (CeAD) with other TIA or ischemic stroke (IS) patients of similar age and sex. Methods: We analysed demographic, clinical and risk factor profiles in TIA and IS patients ≤ 55 years of age with and without CeAD in the large European, multi-centre, Stroke In young FAbry Patients 1 (sifap1) study. Patients were further categorised according to age (younger: 18–44 years; middle-aged: 45–55 years), sex, and site of dissection. Results: Data on the presence of dissection were available in 4,208 TIA and IS patients of whom 439 (10.4%) had CeAD: 196 (50.1%) had CAD, 195 (49.9%) had VAD, and 48 had multiple artery dissections or no information regarding the dissected artery. The prevalence of CAD was higher in women than in men (5.9 vs. 3.8%, p < 0.01), whereas the prevalence of VAD was similar in women and men (4.6 vs. 4.7%, n.s.). Patients with VAD were younger than patients with CAD (median = 41 years (IQR = 35–47 years) versus median = 45 years (IQR = 39–49 years); p < 0.01). At stroke onset, about twice as many patients with either CAD (54.0 vs. 23.1%, p < 0.001) or VAD (63.4 vs. 36.6%, p < 0.001) had headache than patients without CeAD and stroke in the anterior or posterior circulation, respectively. Compared to patients without CeAD, hypertension, concomitant cardiovascular diseases and a patent foramen ovale were significantly less prevalent in both CAD and VAD patients, whereas tobacco smoking, physical inactivity, obesity and a family history of cerebrovascular diseases were found less frequently in CAD patients, but not in VAD patients. A history of migraine was observed at a similar frequency in patients with CAD (31%), VAD (27.8%) and in those without CeAD (25.8%). Conclusions: We identified clinical features and risk factor profiles that are specific to young patients with CeAD, and to subgroups with either CAD or VAD compared to patients without CeAD. Therefore, our data support the concept that certain vascular risk factors differentially affect the risk of CAD and VAD.

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Heinzen, Rosane Porto Seleme. "Comportamento anatômico da artéria cerebral caudal no cão, sem raça definida (Canis familiaris - Linnaeus, 1758) /." Florianópolis, SC, 2000. http://repositorio.ufsc.br/xmlui/handle/123456789/79097.

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Dissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas. Made available in DSpace on 2012-10-17T23:10:43Z (GMT). No. of bitstreams: 0Bitstream added on 2014-09-25T17:06:39Z : No. of bitstreams: 1 153029.pdf: 33672043 bytes, checksum: db38900bb7de87c043bdb27122ebd81c (MD5) Estudo do comportamento anatômico da artéria cerebral caudal em cães, injetados com a Solução de Schlesinger, que, sempre única, surgiu em todos os casos na face ventral do pedúnculo cerebral, rostralmente ao nervo oculomotor, diretamente das artérias comunicantes caudais. No segmento mesencefálico emitiu o ramo para substância perfurada caudal (86,70%), o ramo para a face ventral do pedúnculo cerebral (73,30%), o ramo coróide caudal (98,30%), o ramo para face lateral do pedúnculo cerebral (83,30%) e o ramo para corpo geniculado medial (76,70%). No segmento diencefálico surgiram o ramo piriforme (96,70%), o ramo suprasilvio (100%), o ramo ectomarginal (100%) e o ramo marginal (100%), cujos ramos terminais se anastomosaram com a artéria cerebral média, participando da irrigação da face medioventral do lobo piriforme e do giro parahipocampal, face ventral dos giros composito caudal, esplenial e occipital, e região caudal da face dorsolateral dos giros suprasilvio, ectomarginal , marginal e endomarginal. No segmento telencefálico originaram-se o ramo occipital caudal (100%), o ramo occipital médio (98,30%) e o ramo occipital rostral (96,70%), participando da vascularização do região caudal da face medial dos giros do cíngulo, esplenial e occipital, e da face dorsolateral dos giros endomarginal, marginal e ectomarginal.

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Lacour, Jean-Christophe. "Les infarctus arteriels cerebraux de l'adulte jeune : etude prospective de 152 observations." Nancy 1, 1994. http://www.theses.fr/1994NAN11100.

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MARTINS, Islane Cristina. "Morfologia do círculo arterial cerebral em humanos: hipoplasia do segmento A1 da artéria cerebral anterior e padrão fetal da artéria cerebral posterior." Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/20007.

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Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-07-25T12:54:13Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Islane Cristina Martins.pdf: 2501962 bytes, checksum: f8da8fe4623e40c91559079d260f0d75 (MD5) Made available in DSpace on 2017-07-25T12:54:13Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Islane Cristina Martins.pdf: 2501962 bytes, checksum: f8da8fe4623e40c91559079d260f0d75 (MD5) Previous issue date: 2016-08-26 FACEPE O círculo arterial cerebral é um polígono anastomótico na base do encéfalo que comunica o sistema carotídeo com o sistema vértebro-basilar e as carótidas entre si. Há muitas variações morfológicas nesse polígono e possíveis diferenças entre os sexos, particularmente no segmento A1 da artéria cerebral anterior e na origem da artéria cerebral posterior (ACP). O objetivo do presente estudo foi analisar comparativamente a frequência de hipoplasia do segmento A1 e do padrão fetal da artéria cerebral posterior no homem e na mulher. Foram analisadas retrospectivamente 848 angiografias por ressonância magnética arterial, em 426 homens e 422 mulheres, respectivamente, que se submeteram ao exame no Centro de Diagnóstico Multimagem. Os exames foram escolhidos aleatoriamente entre 1.000 angiorressonância realizadas entre 2010 e 2016, independente do motivo da solicitação médica. Hipoplasia do segmento A1 foi definido por analise qualitativa, quando havia uma nítida assimetria entre os dois segmentos A1 direito e esquerdo bem como o padrão fetal da artéria cerebral posterior. Para análise de hipoplasia foram medidos os diâmetros dos segmentos A1. Para análise do padrão fetal (diâmetro da ACP na origem da artéria carótida>diâmetro do segmento P1) foram analisadas 1.296 artérias carótidas em 648 indivíduos. Na análise estatística utilizouse o teste exato de Fisher. Os homens 152/326 (46,6%) apresentaram hipoplasia de A1 em comparação com 108/322 (33,5%) das mulheres (p<0,01, OR=1,7; IC95% 1,3-2,4). A hipoplasia de A1 nos homens foi mais frequente a direita (20% vs. 15%, p<0,01). O padrão fetal foi mais comum nas mulheres 151/644 (23,4%) do que em homens, 100/652 (15,3%) (p<0,001, OR=1,7; IC95% 1,3-2,2). As mulheres também apresentam mais padrão fetal bilateral do que os homens (8,0% vs. 3,4%; p<0,01; OR=0,4; IC 0,2-0,8). A hipoplasia do segmento A1 da artéria cerebral anterior é mais frequente nos homens e nas mulheres há uma maior frequência do padrão fetal da artéria cerebral posterior. The Circle of Willis is an anastomotic polygon encephalon base that communicates the carotid system with vertebrobasilar system and carotid each other. There are lots of morphological variations that polygon and possible differences between genders particularly in the A1 segment of the anterior cerebral artery and the origin of the posterior cerebral artery (PCA) which are risk factors for anatomical brain aneurysms. The purpose of this study was to comparatively analyze the frequency of hypoplasia of the segment A1 and fetal type of cerebral posterior artery in man and woman. It was retrospectively reviewed 648 magnetic resonance angiographies in 326 men and 322 women, respectively. The tests were randomly chosen among about a thousand magnetic resonance angiographic performed between 2010 and 2016 in Multimagem Diagnostic Center, regardless of the medical reason request. Hypoplasia of the A1 segment was defined by qualitative analysis, when there was a clear asymmetry between the two segments A1, right and left. For hypoplasia analysis were also measured diameters of segments A1. For hypoplasia analysis were also measured diameters of segments A1. For analysis of the fetal type (diameter of the ACP origin of the carotid artery> diameter of the P1 segment of the ACP) were analyzed 1,296 carotid arteries (right and left) in 648 individuals. Statistical analysis was performed using Fisher's exact test. In men 152/326 (46.6%) showed hypoplasia A1 compared to 108/322 (33.5%) of women (p <0.01, OR = 1.7; 95% CI, 1.3-2, 4). Hypoplasia A1 was more common in men right (20% vs. 15%, p <0.01). Fetal type was more common in women 151/644 (23.4%) than in men (100/652; 15.3%) (p <0.001, OR = 1.7; 95% CI, 1.3-2, two). Women also have more bilateral fetal rate than men (8.0% vs. 3.4%; p <0.01). In conclusion, hypoplasia of the A1 segment of the anterior cerebral artery is more common in men and in women there is a greater frequency of fetal type of the posterior cerebral artery. Keywords: Circle of Willis

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38

Chan, Marcelo. "The design and development of a cerebral embolic implant." Thesis, Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/17767.

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39

Wesołowski, Roman. "Development of arterial spin labelling methods for monitoring cerebral haemodynamics." Thesis, University of Nottingham, 2010. http://eprints.nottingham.ac.uk/13854/.

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The work described in this thesis was carried out at the Sir Peter Mansfield Magnetic Resonance Centre at the University of Nottingham between March 2006 and December 2009. All work described in this thesis was performed by the author, except where indicated. This thesis aims to develop and implement ASL techniques to measure haemodynamic responses to neural activity. The development of a new technique Double Acquisition Background Suppression (DABS) is presented as a remedy for a newly discovered artefact affecting Philips Achieva 7 T scanners and other sources of variation in baseline signals such as physiological noise. The new technique (DABS) was developed for simultaneous acquisition of ASL (with suppressed static tissue signal) and BOLD data using the FAIR scheme. This method not only provided a solution to obtaining ASL data at 7 T, despite the Roman Artefact, but also proved to reduce the contribution of physiological noise to ASL images, which is problematic, especially at ultra-high magnetic field strengths. The statistical verification was carried out based on the neural activation induced by a finger-tapping stimulus. A simplified model for quantifying CBVa.with the Look-Locker sampling method is proposed in this thesis to overcome the need for the Step-wise Compartmental Model (SCM). The Look-Locker sampling scheme acquires multiple readout pulses following the labelling and provides an estimation of transit time as well as CBVa. Here the simplified model is used to assess changes due to visual stimulation and validated against the SCM model. The application of LL-FAIR to form CBF and CBVa weighted data with improved SNR compared to traditional single TI FAIR technique is then shown. This method uses a summation over LL-EPI readout pulses and is used to asses the temporal characteristics and absolute changes in CBF and CBVa haemodynamic responses to a short (4.8 s) and long (9.6 s) visual stimulus. LL-FAIR methods are then used to appraise the neural coupling of haemodynamic parameters and assess Grubb's relationship. CBF and CBVa. Data were collected together with CBVtot data from a bolus injection of contrast agent. Assessing Grubb's power-law (CBVtot = CBFCI:)for neuronal activation, which was originally derived in primates during a steady state response of hypercapnia, a was found in this human study to be between 0.22 ± 0.08 and 0.29, dependent on the analysis method. In addition, the power-law relationship between CBVtot and CBVa.was assessed, and resulted in a similar relation, yielding aTA = 0.42 ± 0.14 and 0.40. Since CBF is thought to be driven by CBVa.the power-law between these parameters was also tested with a value of aFA = 1.35 ± 0.64 and 1.21, found in close agreement with earlier animal work.

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Willie, Christopher Kenneth. "Cerebral blood flow in man : regulation by arterial blood gases." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/47074.

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Due to the high metabolic rate of brain tissue and nominal substrate storage, brain perfusion must be precisely regulated to ensure continuous delivery of oxygen and substrates. Cerebral blood flow (CBF) is principally regulated by tissue metabolism, perfusion pressure, autonomic nervous activity, and the partial pressures of arterial oxygen (PaO₂)and carbon dioxide (PaCO₂) – an integrative process thus involving the marked influence of pulmonary gas exchange and cardiovascular function, in addition to intracranial mediators of cerebrovascular resistance. This thesis explicates the roles of PaO₂ and PaCO₂ in human regulation of regional CBF. In study 1, to elucidate their discrete roles, PaO₂ and PaCO₂ were independently manipulated at sea level through the widest range tolerated in humans. Flow reactivity to hypocapnia (low PaCO₂) and hypoxia (low PaO₂) was greater in the vertebral (VA) than internal carotid (ICA) artery, whereas similar reactivity was observed during hypercapnia (high PaCO₂) and hyperoxia (high PaO2₂. Cerebral oxygen delivery was well protected except in cases of extreme hypocapnia. The ventilatory response to hypoxia mitigates falling PaO₂ and reduces PaCO₂, particularly during initial exposure to high altitude. Study 2 assessed regional CBF during ascent to 5050m and every 12 hours during the first 3 days of acclimatization. Although total CBF increased by ~50% and was modestly related to reductions in oxygen saturation of hemoglobin, no regional CBF differences were observed. To extend these findings, Study 3 aimed to determine if cerebrovascular responses to changes in PaO₂ and PaCO₂ differed at 5050m compared to sea level. Despite respiratory alkalosis and partial metabolic compensation at 5050m restoration of PaO₂ to sea level values decreased CBF, and CBF sensitivity to acutely altered PaCO₂ remained similar to sea level. To elucidate the interactive effect on CBF of profound hypoxemia and hypercapnia, study 4 examined the temporal changes in elite breath-hold divers during maximum apneas. Despite 40-50% reductions in arterial oxygen content, CBF elevations were regionally similar (up to +100%) thereby facilitating maintenance of brain oxygen delivery throughout apnea. Although the regulation of CBF is multifaceted, the cerebrovasculature prioritizes oxygen delivery and adjusts to chronic changes in arterial blood gases.

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41

Nasi, Luiz Antonio. "Manipulação da pressão arterial no acidente vascular cerebral isquêmico agudo." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/132167.

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42

Figueiredo, P. M. "Measuring brain perfusion using arterial spin labelling by magnetic resonance imaging." Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275320.

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Modaresi, Kamran Bahari. "Computerised techniques for improved imaging and monitoring of the arterial circulation." Thesis, King's College London (University of London), 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281685.

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44

Liu, Yi. "A study of mathematical modelling and signal processing of cerebral autoregulation." Thesis, University of Southampton, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273880.

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45

Gibert, Guillaume. "Quantification of the Cerebral Perfusion with the Arterial Spin Labelling 3D-MRI method. Quantification of the Cerebral Perfusion with the Arterial Spin Labelling 3D-MRI method." Thesis, KTH, Skolan för teknik och hälsa (STH), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-148020.

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The Arterial Spin Labelling (ASL) method is a Magnetic Resonance technique used toquantify the cerebral perfusion. It has the big advantage to be non-invasive so doesn’tneed the injection of any contrast agent. But due to a relatively low Signal-to-NoiseRatio (SNR) of the signal acquired (only approximately 1% of the image intensity), ithas been hampered to be widely used in a clinical setting so far.The primary objective of this project is to make the method more robust by improvingthe quality of the images, the SNR, and by reducing the acquisition time. DifferentASL protocols with different sets of parameters have been investigated. The modificationsperformed on the protocol have been investigated by analyzing images acquired onhealthy volunteers. An optimized protocol leading to a good trade-off between the differentaspects of the method, has been suggested. It is characterized by a 3:43:44:0mm3with a two-segment acquisition.A more advanced ASL method implies the acquisition of images at different inversiontimes (TI), which is called the mutli-TI method. The influence of the range of TI used inthe method has been explored. An optimized TI range (from 410ms to 3860ms, sampledevery 150ms) has been suggested to make the ASL method as performant as possible.A numerical model and a fitting algorithm have been used to extract the informationon the perfusion from the images acquired. Different models have been investigated aswell as their influence on the reliability of the results.Finally, a criterion has been implemented to evaluate the reliability of the results sothat the clinician or the user of the method can figure out how much he can count onthe results provided by the method.

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GUILHEM, RAYBAUT DOMINIQUE. "Accidents vasculaires cerebraux arteriels et ischemiques du sujet jeune." Nice, 1992. http://www.theses.fr/1992NICE6542.

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47

Herrera, Chirre Alessia Marely. "Signos radiológicos presentes en tomografía computada simple en pacientes con accidente cerebrovascular isquémico. Instituto Nacional de Ciencias Neurológicas. Octubre a diciembre del 2017." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2018. https://hdl.handle.net/20.500.12672/10034.

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Determina los signos radiológicos presentes en tomografía computada simple en pacientes con accidente cerebrovascular isquémico atendidos en el Instituto Nacional de Ciencias Neurológicas de octubre a diciembre del 2017. La investigación realizada es cuantitativa, de tipo observacional, retrospectivo, de corte transversal y descriptivo. Se tuvo como muestra 36 informes radiológicos y/o imágenes tomográficas de los pacientes con presencia de signos radiológicos de accidente cerebrovascular isquémico a los cuales se les realizó una tomografía computada simple durante el periodo comprendido entre octubre a diciembre del 2017, mediante el muestreo no aleatorio, por conveniencia. En el análisis descriptivo las variables cuantitativas se estimaron mediante medidas de tendencia central (las medias, mediana, moda, varianza, valor máximo y valor mínimo), mientras que las variables categóricas nominales se analizaron mediante la estimación de porcentajes, frecuencias absolutas y relativas. La edad promedio fue de 70 años, el mínimo y máximo de edades fue de 45 a 88 años, los pacientes de los grupos etáreos 60 a 74 años y 75 a 89 años tuvieron un 38.9% respectivamente; el sexo masculino tuvo un 63.89%, de ello el grupo de 60 a 74 años tuvo un 33.3%, mientras que el sexo femenino 36.11% de ellas el grupo de 75 a 89 años tuvo 22.2%. Respecto a la localización topográfica el lóbulo parietal presentó un 30.6% y ganglios basales un 22.2%; según territorio afectado la arteria cerebral anterior con 55.6% y la cerebral posterior con 16.7%; el hemisferio cerebral izquierdo estuvo en 58.3% del total, el hemisferio cerebral derecho con 38.9% y en ambos hemisferios con 2.8%. El signo radiológico en tomografía computarizada de la hipodensidad de ganglios basales y/o del parénquima cerebral tuvo una presencia de 66.7%, el borramiento de los surcos de la convexidad en 30.6%, el signo del ribete insular con16.7% y la arteria cerebral media hiperdensa tuvo un 5.6%; asimismo los signos en su forma de presentación única fue 83.3%. En el signo de la hipodensidad de ganglios basales y/o del parénquima cerebral el 30.6% se presentó en el grupo de 60 a 74 años, el 41.7% fueron varones y el 36.1% se presentó en el hemisferio cerebral izquierdo; en el signo de borramiento de los surcos de la convexidad el 11.1% estuvo en los grupos de 60 a 74 años y 75 a 89 años respectivamente, el 19.4% fueron del sexo masculino y el 16.7% presentó daño en el hemisferio cerebral derecho; en el signo del ribete insular el 13.9% se presentó en el grupo de 75 a 89 años, el 11.1% del total fueron varones y 13.9% presentó daño en el hemisferio izquierdo; y por último en el signo de la arteria cerebral media hiperdensa el 2.8% se presentaron en los grupos etáreos de 75 a 89 años y 45 a 59 años respectivamente, el 2.8% fueron mujeres y el 2.8% del total presentó lesión en los hemisferios cerebrales derecho e izquierdo respectivamente. Concluye que los signos radiológicos presentes en tomografía computada simple en pacientes con accidente cerebrovascular isquémico atendidos en el Instituto Nacional de Ciencias Neurológicas de octubre a diciembre del 2017 son los signos directos y con forma de presentación única. Tesis

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48

Rosário, Silvia Rosane Parcias. "Comportamento anatômico da artéria cerebral rostral no cão, sem raça definida (Canis familiaris - Linnaeus, 1758) /." Florianópolis, SC, 1999. http://repositorio.ufsc.br/xmlui/handle/123456789/81068.

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Dissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas. Made available in DSpace on 2012-10-18T22:31:14Z (GMT). No. of bitstreams: 0Bitstream added on 2016-01-09T01:48:24Z : No. of bitstreams: 1 161702.pdf: 28143116 bytes, checksum: ad9689c1cc288d0c26b2e367c4c43a60 (MD5) Estuduo do comportamento anatômico da artéria cerebral rostral no cão, injetados com a Solução de Schlesinger , onde a artéria cerebral rostral à direita e à esquerda, sempre única, originou-se em todos os casos (100,00%) diretamente da artéria carótida interna, dirigindo-se rostromedialmente, contornando o quiasma óptico e ao nível da fissura longitudinal unindo-se, na maioria das vezes, em tronco comum ou, unidas por uma ponte disposta transversalmente, a artéria comunicante anterior. Em seu trajeto apresentou um segmento proximal (arciforme, retilíneo angular ou sinuoso) e outro distal, sendo este último dividido numa porção vertical ou ascendente ( sinuosa, arciforme ou retilínea) e outra horizontal ou supracalosa ( retilínea ou oblíqua). O segmento proximal emitiu a artéria oftálmica interna (91,65%), o ramo perfurante (98,25%) e artéria etmoidal interna (96,70%). A porção vertical do segmento distal, a artéria fronto-basilar (96,70%), frontal rostral (95,95%), frontal média (98,25%) e frontal caudal (96,70%). O segmento distal, nas sua porção horizontal, emitiu as artérias paracruzada, parietal e occiptal que estavam presentes em todas as peças examinadas (100,00%), além da artéria pericalosal caudal, onde todos os ramos exibiram, com o predomínio, uma simetria bilateral de calibre e de trajeto. A artéria pericalosal em alguns casos uniu-se por anastomose com um ramo da artéria cerebral caudal, ou mesmo formando uma rede anastomótica.

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49

Paschoal, André Monteiro. "Otimização do contraste em Arterial Spin Labeling multifase." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-29092015-101918/.

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Imagem por ressonância magnética tem sido um dos principais métodos para a aquisição de imagens para diagnósticos na medicina, em especial para a obtenção de medidas do cérebro. Apesar de se mostrar muito eficiente, o método atualmente utilizado para a realização da ressonância em hospitais e centros de diagnósticos, em alguns casos, necessita da aplicação de um contraste de gadolínio intravenoso. Essa injeção do contraste pode mostrar-se um tanto quanto invasivo, podendo em alguns casos resultar em algumas reações indesejadas nos pacientes. Em vista disso, um método que tem sido bastante estudado recentemente e muito promissor é o de Arterial Spin Labeling (ASL). Este método tem como sua principal vantagem o fato de não ser invasivo e de possibilitar a quantificação da perfusão sanguínea cerebral (CBF). No presente trabalho, foi feita uma otimização do contraste na aquisição das fases mais tardias da metodologia de ASL em múltiplas fases. Isso foi feito através de uma modulação do angulo de flip e é particularmente importante para a análise das imagens de pacientes com problemas neurovasculares, principalmente aqueles associados ao retardo nos tempos de trânsito do sangue arterial. Também, foi realizada toda a obtenção e processamento de dados para a avaliação da perfusão sanguínea cerebral utilizando o método proposto. Magnetic resonance imaging has been one of the major methods to acquire images for medical diagnoses, specially, for obtaining brain images. Although the major method using magnetic resonance used today has high efficiency, in some cases it needs an injection of intravascular contrast agent, like gadolinium. This contrast agent application can be a lot invasive for the patient, in extremes cases resulting to allergic reactions the patient. Therefore, a method that has been studied recently and is very promising is the Arterial Spin Labeling (ASL). This method has the major advantage the feature that it is completely non invasive for the patient and it allows to quantify the perfusion value. In this work, it was implemented an optimization of the contrast in the late phases of ASL multiphase acquisition. It was made using a modulation of the flip angle and it is critical to analyze images from patients with some neurovascular disease, especially those associated with arterial blood transit time delay. Besides that, it was made all data acquisition and data processing for the brain perfusion evaluation using the proposed method.

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Nunes, Sílvia Daniela de Macedo Teixeira. "Risco cerebrovascular e arterial periférico numa população com aterosclerose coronária limitada." Master's thesis, Universidade da Beira Interior, 2012. http://hdl.handle.net/10400.6/1107.

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Objectivos: Neste trabalho de investigação procurou responder a 3 objectivos primordiais: (1) determinar se o score de cálcio baixo identifica ou não indivíduos com escasso atingimento aterosclerótico nos territórios cerebrovascular e vascular periférico; (2) determinar se o reduzido envolvimento coronário, traduzido por um score de cálcio coronário baixo, se traduz em reduzida ocorrência de eventos cardiovasculares major; e (3) correlacionar esse risco com as escalas clássicas. Introdução: Estudos recentes mostram que a quantificação de cálcio nas artérias coronárias, score coronário de cálcio, é um excelente marcador do processo aterosclerótico, melhorando a previsão do risco DCV, sobretudo em indivíduos de risco intermédio. O cálcio coronário (CC) é encontrado em lesões avançadas, mas também pode estar presente em pequenas quantidades em lesões ateroscleróticas recentes que se desenvolvem durante a 2ª ou 3ª década de vida. A quantidade de CC aumenta com a idade, embora a taxa de progressão do CC na idade adulta esteja relacionada com a prevalência de factores de risco em idades precoces. Por esse motivo, a prevalência de um SCC mensurável é inferior em pessoas com menos fatores de risco na sua juventude. Métodos: Realizou-se um estudo observacional composto por 2 partes, uma prospetiva e outra retrospetiva. O estudo prospetivo englobou 54 doentes, que completaram o estudo, nos quais o SCC determinado, no segundo semestre de 2010, foi inferior ou igual a 100. Este estudo foi dividido em duas partes realizadas em tempos diferentes. Numa primeira fase, convocou-se os doentes e averiguou-se os factores de risco presentes e ainda se calculou o ITB. Numa segunda fase foram chamados a realizar o eco-doppler carotídeo. O estudo retrospetivo consistiu na consulta dos processos digitais e em papel de 119 doentes que realizaram o Angio-TC no segundo semestre de 2009 e no primeiro semestre de 2010, nos quais o SCC obtido foi inferior ou igual a 100. Os resultados obtidos no presente estudo foram analisados com recurso aos programas de análise estatística de dados SPSS Statistics Vs 19 e Microsoft Office Excel 2010. Resultados: No estudo prospetivo, 64,8% da amostra era do sexo feminino (35 indivíduos) e a idade média era 64 ±9,6 anos. Cinquenta e três por cento da amostra apresentou um SCC de 0. A quantificação de risco pelas escalas clássicas foi em média 11,8±9,7% e 2,8±3,6% segundo a FRS e a Euroscore, respetivamente. Relativamente à existência de aterosclerose noutros territórios arteriais, 90,7% dos pacientes apresentaram ITB nos valores normais (≤0,9), 53,3% e 55,6% apresentaram espessura ≥1mm e placas carotídeas, respetivamente. Não se encontrou uma relação estatisticamente significativa entre o SCC e o ITB (p=0,22), EIM (p=0,33), FRS (p=0,25) e Euroscore (p=0,06). As escalas clássicas também não apresentaram correlação com o ITB e a EIM. No estudo retrospetivo a maioria dos participantes também era do sexo feminino (52,9%) e a idade média foi de 61,8±10,5 anos. Neste último não se verificou a ocorrência de nenhum evento major (Morte CV, EAM não fatal, AVC não fatal) ao fim de um ano de realização do Angio-TC. Discussão: Apesar do presente estudo ter sido realizado em doentes sintomáticos referenciados para angio-TAC cardíaca (para esclarecimento da clínica), valores de score de cálcio coronário baixo associaram-se a uma elevada a uma considerável prevalência de atingimento vascular cerebrovascular e periférico. Embora não tivesse sido possível estabelecer uma correlação entre este score e as escalas clínicas de estratificação de risco, a prevalência dos factores de risco foi elevada e superior à que é descrita para a população portuguesa. Paralelamente, a identificação de cálcio coronário associou-se a uma maior taxa de prescrição de fármacos vasoprotectores, nomeadamente hipolipemiantes e hipotensores. Tratando-se de uma população com risco vascular à priori significativo, a taxa de eventos registados pela análise retrospetiva revelou-se muito baixa e inferior àquela que seria esperada para uma população com as mesmas características.

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Dissertations / Theses on the topic 'Cerebral arteries'

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