974 resultados para Intracranial aneurysm quanti cation


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Background We sought to test, in men Undergoing ultrasound screening for abdominal aortic aneurysms (AAA) in Western Australia, clinical impressions that the prevalence of AAA is high in Dutch migrants and low in migrants from Mediterranean countries. Methods In a. population-based trial, men undergoing screening for AAA completed a questionnaire covering their place of birth, smoking habits and consumption of alcohol, meat, fish, salt and milk. We examined the variation by place of birth in the mean, median, 95th and 99th centiles of infrarenal aortic diameter and the prevalences of AAA defined by criteria of 30 mm, 50 mm and by the 95th and 99th centiles, in men born in Australia, of aortic diameter adjusted for height. Findings Overall, 12 203 (70.5%) of the 19 583 men took up the invitation to undergo ultrasound screening. The prevalence of AAA defined by absolute diameter was higher than average in men born in The Netherlands or Scotland (more of whom had ever smoked or smoked currently) and lower in men of Mediterranean origin (more of whom drank alcohol currently). There were no consistent relationships with simple dietary: data. Correction of aortic diameter for height eliminated the significant heterogeneity in prevalence of large AAA, although a threefold variation in prevalence of AAA exceeding the 95th centile of height-adjusted diameter in Australian men persisted. Interpretation In our cohort of men, which is subject to both 'healthy migrant' and 'survivor' effects, if it exists at all, any 'Mediterranean paradox' for AAA is more modest than that for coronary disease.

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A series of alpha-sialon (alpha') compositions containing mixed stabilising cations were prepared, by introducing additional CaO to a basic Sm alpha-sialon compositions. The thermal stability of these Sm-Ca-containing alpha-sialon phases was investigated using XRD, SEM and EDXS techniques. It was found that the addition of calcium into the Sm alpha-sialon systems greatly improved the stability of the alpha-sialon phases. Calcium was found to be incorporated into the alpha-sialon structure, coexistent with the samarium, and partitioning of the calcium and samarium was observed between the alpha' phase and grain boundary phases. This indicates a technique which may be used to improve the thermal stability of the alpha' phase while maintaining good refractory phases at the gialon grain boundaries. (C) 2003 Elsevier Science B.V. All rights reserved.

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Background: Although there is evidence demonstrating an association between chronic obstructive pulmonary disease (COPD) and abdominal aortic aneurysm (AAA), it is not clear whether COPD predicts greater rates of expansion of established aneurysms. We sought such an association in a cohort of men with aneurysms detected in a population-based study of screening for aneurysms. Methods: In addition to regular aortic ultrasound scans, 179 men with AAA underwent full lung function testing in order to identify the presence of COPD and its subgroups, emphysema and other obstructive ventilatory defects (OVD). The rate of expansion of each aneurysm was calculated and the men were divided into 'rapid expanders' (3 mm or more per year) and 'slow expanders' (less than 3 mm per year). Any association with the presence of COPD or smoking was tested using a multivariate model. Results: Over a median follow-up period of 36 months the mean rate of aortic expansion for the cohort of 179 men was 2.1 mm/year. There was no significant difference in prevalence of COPD (68% overall) or having ever been a smoker (87% overall) between the rapid expanders and the slow expanders. Conclusions: Although there was a high prevalence of COPD among men with an AAA, there was no association between the rate of expansion of AAA and the presence of any form of this disease.

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Novel cyclopropyl containing fatty acids are good substrates for P450(BM3) catalysed hydroxylation and analysis of their oxidation products indicates the presence of a radical intermediate (maximum rebound rate 2.6x10(10) s(-1)) and the absence of any cationic intermediate.

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Background: The purpose of the present paper was to investigate whether screening for abdominal aortic aneurysm (AAA) causes health-related quality of life to change in men or their partners. Methods: A cross-sectional case-control comparison was undertaken of men aged 65-83 years living in Perth, Western Australia, using questionnaires incorporating three validated instruments (Medical Outcomes Study Short Form-36, EuroQol EQ-5D and Hospital Anxiety and Depression Scale) as well as several independent questions about quality of life. The 2009 men who attended for ultrasound scans of the abdominal aorta completed a short prescreening questionnaire about their perception of their general health. Four hundred and ninety-eight men (157 with an AAA and 341 with a normal aorta) were sent two questionnaires for completion 12 months after screening, one for themselves and one for their partner, each being about the quality of life of the respondent. Results: Men with an AAA were more limited in performing physical activities than those with a normal aorta (t-test of means P = 0.04). After screening, men with an AAA were significantly less likely to have current pain or discomfort than those with a normal aorta (multivariate odds ratio: 0.5; 95% confidence interval (Cl): 0.3-0.9) and reported fewer visits to their doctor. The mean level of self-perceived general health increased for all men from before to after screening (from 63.4 to 65.4). Conclusions: Apart from physical functioning, screening was not associated with decreases in health and well-being. A high proportion of men rated their health over the year after screening as being either the same or improved, regardless of whether or not they were found to have an AAA.

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An Adobe (R) animation is presented for use in undergraduate Biochemistry courses, illustrating the mechanism of Na(+) and K(+) translocation coupled to ATP hydrolysis by the (Na, K)-ATPase, a P(2c)-type ATPase, or ATP-powered ion pump that actively translocates cations across plasma membranes. The enzyme is also known as an E(1)/E(2)-ATPase as it undergoes conformational changes between the E(1) and E(2) forms during the pumping cycle, altering the affinity and accessibility of the transmembrane ion-binding sites. The animation is based on Horisberger`s scheme that incorporates the most recent significant findings to have improved our understanding of the (Na, K)-ATPase structure function relationship. The movements of the various domains within the (Na, K)-ATPase alpha-subunit illustrate the conformational changes that occur during Na(+) and K(+) translocation across the membrane and emphasize involvement of the actuator, nucleotide, and phosphorylation domains, that is, the ""core engine"" of the pump, with respect to ATP binding, cation transport, and ADP and P(i) release.

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Editor—We reported the study in a transparent fashion and were deliberately cautious in our conclusions. Australia and the United Kingdom are very different with regard to arrangements for primary care, which did not permit us to undertake a preliminary assessment of the eligibility of men for screening before we randomised them and issued half invitations to attend for the ultrasound examination.

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Introduction. We describe a series of 10 children with intracranial hypertension complicating fulminant hepatic failure submitted to intracranial pressure (ICP) monitoring for intensive care an transplantation management. Patients and methods. Information from pediatrics patients acute liver failure admitted to our hospital was collected in a standard protocol form. We analyzed data from 10 patients, medium age 5.2 years old. In this period we studied aspects as ICP transducer used, number of days with ICP monitoring and complications of ICP monitoring. Results. Hepatitis A was diagnosed in five patients and hepatitis B in two cases. The initial ICP were 2 to 24 mmHg in transducer Seven patients died, four due to intracranial hypertension, included the patient operated for subdural hematoma, and three with transplantation failure. Only, a case of hematoma was verified. Conclusions. The application of ICP monitoring allows intensive care for aggressive ICP management. It can be used in children without adaptations. [REV NEUROL 2009: 48: 134-6]

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Direct carotid-cavernous fistula (CCF) is a direct communication between the internal carotid artery (ICA) and the cavernous sinus. Some patients treated with detachable balloons develop pseudoaneurysms or present with a true aneurysm recanalization in the cavernous ICA with poorly known long-term radiological and clinical progression. The objective of the present study was to evaluate the long-term clinical and radiological progression of patients treated with detachable balloons. The present study evaluated 13 patients previously treated for direct CCF by an endovascular approach. The follow-up period ranged between 19 and 128 months. Ophthalmological evaluation demonstrated alterations in eight patients (61.5%). All of these alterations were already present from the moment of the treatment and displayed no signs of progression. Cranial magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) were performed in all patients, and 11 pseudoaneurysms were demonstrated in ten of the 11 patients in whom ICA patency had been preserved. Five patients were submitted for cerebral digital subtraction angiography (DSA) to characterize the pseudoaneurysms previously observed on MRA studies, with no significant differences in morphology, size, aneurismal neck, and number of lesions. Endovascular treatment of direct CCF with detachable balloons has been shown to be a long-term effective and stable therapeutic method. The authors found asymptomatic pseudoaneurysms in 91% of cases where the ICA patency was preserved. MRI and MRA demonstrated an accuracy similar to that of DSA in the diagnosis of pseudoaneurysms of cavernous ICA.

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Background: Brain injury is responsible for significant morbidity and mortality in trauma patients, but controversy still exists over optimal fluid management for these patients. This study aimed to investigate the effects of acute hemodilution with hydroxyethyl starch (HES) or lactated Ringer`s solution (LR) in intracranial pressure (ICP) and cerebral perfusion pressure (CPP) in dogs submitted to a cryogenic brain injury model. Methods: Design-Prospective laboratory animal study. Setting-Research laboratory in a teaching hospital. Subjects-Thirty-five male mongrel dogs. Interventions-Animals were enrolled to five groups: control, hemodilution with LR or HES 6% to an hematocrit target of 27% or 35%. Results: ICP and CPP levels were measured after cryogenic brain injury. Hemodilution promotes an increment of ICP levels, which decreases CPP when hematocrit target was estimated in 27.% after hemodilution. However, no differences were observed regarding crystalloid or colloid solution used for hemodilution in ICP and CPP levels. Conclusions: Hemodilution to a low hematocrit level increases ICP and decreases CPP scores in dogs submitted to a cryogenic brain injury. These results suggest that excessive hemodilution to a hematocrit below 30% should be avoided in traumatic brain injury patients.

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An 8-month-old child presented with a right pulsatile neck mass. The tumor`s rapid increase in size and respiratory problems prompted image evaluation. An external carotid artery aneurysm was found, which was compressing other neck structures. The patient underwent aneurysm resection and ligation at its insertion on the common carotid artery. Recovery was uneventful and no further aneurysms on other arteries were found.

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OBJECTIVE: A giant fusiform aneurysm in the posterior cerebral artery (PCA) is rare, as is fenestration of the PCA and basilar apex variation. We describe the angiographic and surgical findings of a giant fusiform aneurysm in the P1-P2 PCA segment associated with PCA bilateral fenestration and superior cerebellar artery double origin. CLINICAL PRESENTATION: A 26-year-old woman presented with a 2-month history of visual blurring. Digital subtraction angiography showed a giant (2.5 cm) fusiform PCA aneurysm in the right P1-P2 segment. The 3-dimensional view showed a caudal fusion pattern from the upper portion of the basilar artery associated with a bilateral long fenestration of the P1 and P2 segments and superior cerebellar artery double origin. INTERVENTION: Surgical trapping of the right P1 -P2 segment, including the posterior communicating artery, was performed by a pretemporal approach. Angiograms performed 3 and 13 months after surgery showed complete aneurysm exclusion, and the PCA was permeated and filled the PCA territory. Clinical follow-up at 14 months showed the patient with no deficits and a return to normal life. CONCLUSION: To our knowledge, this is the first report of a giant fusiform aneurysm of the PCA associated with P1-P2 segment fenestration and other variations of the basilar apex (bilateral superior cerebellar artery duplication and caudal fusion). Comprehension of the embryology and anatomy of the PCA and its related vessels and branches is fundamental to the decision-making process for a PCA aneurysm, especially when parent vessel occlusion is planned.

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OBJECTIVE: We studied the angiographic findings in patients with small epidural hematomas and cranial fractures crossing over the trajectory of the middle meningeal artery and its branches. Additionally, the Occurrence of traumatic vascular lesions and their clinical relevance and treatment are discussed. METHODS: A consecutive analysis was performed for 24 patients who harbored small epidural hematomas in middle meningeal artery topography associated with cranial fractures. Computed tomographic scans and plain x-ray studies were used to diagnose linear cranial fractures. Patients with large epidural hematomas or associated traumatic lesions were excluded from the study. Selective ipsilateral external carotid angiograms were obtained, and an endovascular procedure was performed if any vascular injury was evidenced. RESULTS: In all patients with cranial fractures crossing over the middle meningeal artery and its branches, some kind of vascular lesion was seen. Two types of findings were noted: active extravasation of the contrast medium (71%) and pseudoaneurysms (29%). Early filling of diploic vessels was found in 8.3% of fractures concomitantly with active extravasation. Embolization was performed in all patients. No additional enlargement of the epidural hematoma was observed, and the postoperative period was uneventful. CONCLUSION: This study shows that pseudoaneurysms and active extravasation of contrast are common findings in this subset of patients. Although the natural history of these lesions is still poorly understood, additional investigation with ipsilateral external carotid angiography may be recommended, considering the potentially catastrophic consequences of late rupture.