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Background: It is uncertain whether the location and size of a ruptured intracranial aneurysm (IA) independently influences the outcome of subarachnoid hemorrhage (SAH). Objective: To determine the independent relationship of location and size of a ruptured IA with serious clinical outcomes after SAH in an Australasian population-based study. Methods: From 432 first-ever cases of primary SAH registered prospectively over 12 months in 4 Australasian cities between 1995 and 1998, the demographics, clinical features, risk factors and results of investigations were obtained, including the location and size of any ruptured IA as assessed by cerebral angiography, computed tomography and/or magnetic resonance imaging. Location was classified as either anterior (i.e. anterior communicating artery, internal carotid artery and middle cerebral artery) or posterior circulation (i.e. posterior communicating artery, posterior inferior cerebellar artery, basilar artery and vertebral artery), and size was classified as <5, 5-9 and ≥10 mm. Outcomes recorded during hospitalization were rebleeding, delayed ischemia, hydrocephalus, residual neurological impairment and in-hospital death. Logistic regression analysis was used to evaluate the effects of IA location and size on outcome, independent of other potential prognostic factors. Data are reported with odds ratios (OR) and 95% confidence intervals (CI). Results: IA location and size were confirmed separately in 299 and 252 patients, respectively. Patients with a posterior circulation IA had a lower rate of rebleeding than those with an anterior circulation IA (adjusted OR: 0.11; 95% CI: 0.02-0.87), but otherwise there was no significant relationship between IA location and outcome. Patients with a larger ruptured IA had higher risks of rebleeding (p = 0.02 for trend) and in-hospital death (p = 0.001) after controlling for age, sex, ethnicity, location of the ruptured IA and neurosurgical intervention. Conclusion: IA location in the posterior circulation was associated with a lower risk of rebleeding than IA in the anterior circulation. A larger IA size was associated with higher risks of rebleeding and in-hospital death. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: We aimed to assess quality of life (QOL) and its predictors in stroke survivors after local intra-arterial thrombolysis (IAT) as well as to measure QOL according to the site of pretreatment vessel occlusion. Methods: From January 2000 to April 2004, 175 consecutive patients underwent IAT for acute ischemic stroke. Clinical and radiological data were collected prospectively. We contacted 135 stroke survivors after a mean of 923 (±431) days, 132 responded. QOL, assessed with EuroQol (EQ-5D), and functional abilities, measured with the modified Rankin Scale (mRS) and the Barthel Index, were compared, and predictors of QOL were analyzed. Results: Measured with EQ-5D, 56% of the patients reported a good QOL (EQ-5D Index ≥70). Low mRS and high Barthel Index scores at follow-up were associated with better overall QOL (Kendall’s tau >0.5). Nevertheless, 25% of the functionally independent patients (mRS 0–2) indicated a markedly impaired QOL (EQ-5D Index <70) and 10% of disabled patients indicated good QOL. QOL was significantly lower in patients with occlusion of the internal carotid artery compared to patients with occlusion of the basilar artery or the M1, M2 or M3/4 segment of the middle cerebral artery (EQ-5D Index: p = 0.005). A high National Institute of Health Stroke Scale score on admission and occlusion of the internal carotid artery were independent predictors of impaired QOL (p < 0.05). Conclusion: More than half of the stroke survivors treated with IAT reported a good QOL, mostly survivors with mild disabilities. QOL assessment gives information that is not provided by traditional outcome scores. Our results support guidelines to measure QOL in stroke research. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Transcranial Doppler is a sensitive test for patent foramen ovale (PFO), but an absent temporal window precludes this in 12–15% of patients. We investigated whether the brachial (BrA), common carotid (CCA) or common femoral (CFA) artery provided reliable alternatives. Methods: Patients underwent simultaneous insonation of a middle cerebral artery (MCA, n = 66) and either (a) the BrA (n = 22), (b) CCA (n = 20) or (c) CFA (n = 24) with a 2-MHz transcranial Doppler probe. Results: The correlation between microbubble emboli counts in the MCA and the peripheral arteries was (a) r = 0.67 (95% CI 0.53–0.77) for the BrA, (b) r = 0.80 (95% CI 0.71–0.87) for the CCA and (c) r = 0.92 (95% CI 0.89–0.95) for the CFA. The agreement for detection of PFO was best using the CFA with a kappa of 0.95 (95% CI 0.66–1.0). Conclusion: The CFA is a simple and reliable alternative to the MCA, but the criteria for diagnosis of a PFO are different. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Common carotid intima-media thickness (CIMT) has been related to cardiovascular risk factors, coronary atherosclerosis and a higher risk of myocardial infarction. Evaluation of intracranial arteries by transcranial Doppler explores the presence of vascular dysfunction at this level. We tested the hypothesis that CIMT and Doppler Pulsatility Index (DPI) can be related to the Thrombolysis in Myocardial Infarction (TIMI) risk score for non-ST-elevation acute coronary syndrome (nST-ACS). The relation to the prognosis after an acute event was also assessed. Methods: We recruited 126 consecutive patients (80 males; mean age: 66.6 ± 13.1 years) admitted with nST-ACS. A carotid assessment with bidimensional mode, measuring the CIMT in the posterior wall of the common carotid artery, and a transcranial Doppler assessment of the middle cerebral artery, with measurement of the Pulsatility Index were carried out. Clinical follow-up at 6 months was performed for endpoints (cardiovascular death, recurrent ACS or revascularization). Results: Fifty-nine patients had an abnormal (≥0.8 mm) CIMT, whilst 70 patients had an abnormal DPI (≥1.2). CIMT was correlated with TIMI risk score (Pearson r: 0.26; p = 0.004), whilst abnormal DPI was associated with TIMI risk scale (p < 0.001). Using a logistic regression analysis, the presence of an abnormal CIMT was only related to age ≥65 (p = 0.0012) and diabetes mellitus (p = 0.0028). Abnormal DPI was also associated with age ≥65 (p < 0.0001) and diabetes mellitus (p = 0.0466). Neither CIMT nor DPI were related to 6 months’ clinical outcome. Conclusions: Patients with nST-ACS have a high prevalence of dates of abnormal DPI, which was associated with increased CIMT. Both variables were related to age and diabetes but not with clinical outcomes. [ABSTRACT FROM AUTHOR]

Background and Purpose: The mechanism of stroke in patients with atherosclerotic occlusive disease and hemodynamic failure may be primarily hemodynamic or a combination of hemodynamic and embolic factors. The purpose of this study was to investigate the clinical and imaging features of stroke in these patients. Methods: Eleven patients with complete atherosclerotic carotid artery occlusion and increased oxygen extraction fraction measured in the hemisphere distal to the occlusion developed an ischemic stroke during the observation phase of a prospective study of cerebral hemodynamics and stroke risk. The medical and study records related to the endpoint event for these 11 patients were reviewed. Records were reviewed for evidence of associated hypotension and for specific details of the neurological deficit. Infarct location was characterized, based on review of imaging and clinical features, as: (1) middle cerebral artery (MCA) core; (2) possible cortical border zone, or (3) internal border zone. Results: One patient had a retinal infarction; the remaining 10 had MCA territory strokes. Six of the 10 infarctions occurred in the MCA core territory. Two of these 6 were fatal hemispheric events. One of the 10 infarctions occurred in the cortical border zone region. Two of the remaining 3 infarctions were localized to the internal border zone. One was indeterminate. Conclusions: The clinical features and radiological patterns of stroke in many patients with hemodynamic impairment failure and carotid occlusion are most consistent with large artery thromboembolic stroke. These data suggest a synergistic effect between embolic and hemodynamic mechanisms for large artery thromboembolic stroke. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

In a fetal-type posterior circle of Willis (FTP) there is an embryonic derivation of the posterior cerebral artery (PCA) from the internal carotid artery (ICA). Besides the fact that a larger area is thus dependent on the ICA, leptomeningeal vessels cannot develop between the anterior and posterior circulation. The tentorium namely prevents cerebellar vessels from connecting to the PCA territory. Therefore patients with an FTP could be more prone to develop vascular insufficiency. An overview of the literature is given. We propose to define a partial FTP, in which a small P1 segment between the basilar artery and the postcommunicating part of the PCA is present, and a full FTP, in which the P1 segment is absent. Whether a full FTP is a risk factor for stroke should be subject of further investigation. [ABSTRACT FROM AUTHOR]

Background: To investigate the effect of early (<6 h) versus delayed (>6 h) recanalization on infarct pattern in acute middle cerebral artery (MCA) occlusion. Methods: 35 patients with acute MCA occlusion (M1 segment; symptom onset <6 h) were analyzed. Stroke MRI was performed immediately after admission (day 0), and on days 1 and 7. In addition, vessel status was assessed within 6 h, at 24 h and on day 7. Patients were grouped according to early (≤6 h, n = 10), delayed (6–24 h, n = 8) or no recanalization within 24 h (n = 17). Infarct patterns between the three subgroups were compared on normalized day 1 diffusion-weighted imaging (DWI) data. Lesion plots were generated for the three subgroups depicting voxel by voxel the relative frequency of infarction. Results: Lesion growth was significantly larger in the group without recanalization (125 ± 100 cm3; mean ± SD) compared to patients with early (41 ± 42 cm3; p = 0.02) or delayed (47 ± 45 cm3; p < 0.05) recanalization. The analysis of infarct patterns revealed extensive sparing of peripheral cortical regions in both the early and delayed recanalization groups compared to the persistent occlusion group. In the early/delayed recanalization groups, cortical involvement was often limited to the central MCA territory (i.e. insular region and adjacent cortex, in addition to the basal ganglia). The final infarct volume was 80 ± 71 cm3 in patients with early, 93 ± 62 cm3 in those with delayed, and 194 ± 156 cm3 in those without recanalization. Conclusions: Delayed recanalization significantly limits DWI lesion expansion in patients with proximal MCA occlusion and selectively saves peripheral cortical regions. Collateral supply to the peripheral MCA territory may be sufficient for an extended period of time. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background and Purpose: Type 2 diabetes mellitus (DM2) is associated with an increased risk of stroke. DM2 is also associated with cognitive impairments. Vascular dysfunction, such as impaired cerebrovascular reserve capacity (CVR), may be a determinant of these changes, but previous studies on CVR in DM2 have provided variable results in selected populations of patients. We aimed to examine CVR in a population-based sample of DM2 patients. Methods: The CO2 reactivity of the middle cerebral artery was examined using transcranial Doppler ultrasonography in 81 DM2 patients and 38 controls. In DM2 patients CVR was correlated with diabetic parameters, vascular risk factors and cognitive functioning.Results: CVR was similar in patients and controls (51 vs. 49%). Within the DM2 group, there was no statistically significant relationship between CVR and DM duration, HbA1c, albuminuria, blood pressure, intima-media thickness and cognition. CVR tended to be lower in diabetic patients with retinopathy [46 vs. 55%, mean difference: –7.9 (confidence interval –18.0, 2.2)]. Conclusion: We conclude that CVR is not impaired in unselected patients with DM2 and probably does not, therefore, play a major role in the aetiology of cognitive impairment. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Up until the 17th century, ideas surrounding the discovery of encephalic arteries were to remain largely influenced by the political and religious ideologies of the era. Parts of the encephalic arterial system have been called after several anatomists from this earlier period. From the 18th century onwards, scientists and doctors in particular, liberated themselves from the political and religious trends which had governed their work in previous centuries. Some progress was made by applying the clinico-anatomical method to neurology, but it was only at the end of the 19th century and the beginning of the 20th century that discoveries about encephalic arteries had gained ground. During the same period, anatomists in several countries were producing detailed descriptions of this arterial system. Moreover, this period saw the advent of the first generation of vascular neurologists, one of whom, Charles Foix, is considered as the founder of the discipline. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Analysis of microembolic signals (MES) suggests a change of flow direction (CFD). The aim of the present study was to relate MES direction in an amplitude plot, based on the radiofrequent (RF) signal, to the vascular anatomy as seen with transcranial color-coded duplex (TCCD). Methods: In 5 patients undergoing heart valve surgery or aortic arch replacement, preoperatively TCCD of the distal part of the internal carotid artery and the middle and anterior cerebral arteries on the right side was performed to determine potential depths of changes in flow direction. Peroperatively, a transcranial pulsed Doppler (TCD) monitoring probe was fixed over the right temporal bone. A customized RF-based system, connected to the TCD device, captured and stored the MES. Off-line, the color-coded amplitude of the clutter-filtered RF signals was plotted as a function of time (sample interval 0.17 ms) and depth (sample interval 0.05 mm). Results: A total of 313 MES were recorded in 4 patients with 66 MES (21%) showing a CFD. All MES with CFD could be assigned to maximally three different depth values, six out of eight CFD depth values as seen with the RF analysis were within 1 mm from a turn in flow direction as estimated with TCCD. Conclusions: A CFD of MES occurred at a very limited number of depths and corresponded mostly with the intracranial vascular anatomy, namely a turn of the flow direction in the intracranial vessels as observed with TCCD. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: In acute infarction involving the anterior circulation, the ipsilateral posterior cerebral artery (PCA) often appears to be longer than the contralateral PCA on magnetic resonance angiography. We described this finding as dominant ipsilateral PCA (DIPCA). We sought to find the frequency of DIPCA and its predictors. Methods: We recruited 164 consecutive individuals with acute infarct involving the anterior circulation, and analyzed their radiological and clinical features. Results: DIPCA was noted in 27 patients (16.5%). It was more frequent in patients with than in patients without steno-occlusive disease of the ipsilateral anterior circulation (30.5 vs. 2.4%, p < 0.001). Multivariate analysis revealed a significant relationship between the severity of arterial lesions in the ipsilateral anterior circulation and DIPCA (p = 0.039). Conclusions: DIPCA may reflect increased leptomeningeal collateral flow via the ipsilateral PCA, and its development may be dependent on the stenotic anterior circulation.Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]