Leptomeningeal collateral status predicts outcome after middle cerebral artery occlusion.

OBJECTIVES: Perfusion through leptomeningeal collateral vessels is a likely pivotal factor in the outcome of stroke patients. We aimed to investigate the effect of collateral status on outcome in a cohort of unselected, consecutive stroke patients with middle cerebral artery occlusion undergoing reperfusion therapy. MATERIALS AND METHODS: This retrospectively planned analysis was passed on prospectively collected data from 187 consecutive patients with middle cerebral artery occlusion admitted within 4.5 hours to one center and treated with intravenous thrombolysis alone (N = 126), mechanical thrombectomy alone (N = 5), or both (N = 56) from May 2009 to April 2014. Non-contrast CT (NCCT) and computed tomography angiography (CTA) were provided on admission and NCCT repeated at 24 hours. Collateral status was assessed based on the initial CTA. Hemorrhagic transformation was evaluated on the 24-hour NCCT and according to European Cooperative Acute Stroke Study (ECASS) criteria. Modified Rankin Scale score was assessed at 90 days, and mortality at 1 year. RESULTS: At 90 days, median (IQR) modified Rankin Scale score in patients with poor collateral status was 4 (3-6) compared to 2 (1-4) in patients with good collateral status (P < .0001). Patients with poor collateral status were less likely to achieve a good 90-day outcome (modified Rankin Scale score 0-2) (Adjusted odds ratio 0.27, 95% CI: 0.09-0.86). During the first year, 40.9% of patients with poor collateral status died vs 18.2% of the remaining population (P = .001). CONCLUSIONS: Leptomeningeal collateral status predicts functional outcome, mortality, and hemorrhagic transformation following middle cerebral artery occlusion.

Stroke severity and incidence of acute large vessel occlusions in patients with hyper-acute cerebral ischemia: results from a prospective cohort study based on CT-angiography (CTA).

BACKGROUND: The frequency of acute large vessel occlusions in relation to clinical severity has not yet been established in a comprehensive, consecutive and unselected cohort of patients with hyper-acute cerebral ischemia. AIM: The aim of this study was to establish the frequency of acute large vessel occlusions and describe the relations to the National Institutes of Health Stroke Scale (NIHSS), lesion site and time from symptom onset in unselected consecutive patients with hyper-acute cerebral ischemia. METHODS: A prospective single hospital registry was based on consecutive unselected patients admitted from July 2009 to December 2011 with symptoms of acute cerebral ischemia within 4.5 h from symptom onset. ICA, M1, M2, ACA, PCA, BA and VA were assed for occlusions. Best NIHSS-cut-off values were calculated based on sensitivity and specificity for detecting any, anterior and posterior occlusions and the effect of time after symptom onset was assessed. RESULTS: Six hundred thirty-seven patients, with admission NIHSS: 1-42, were included; 183 patients presented with acute vessel occlusions (28.7%) in 15 different combinations of occlusions. The best NIHSS-cut-off for detecting any occlusion was 6. NIHSS is highly depending on lesion site, highest values being observed in relation to combined and M1 occlusions. CONCLUSION: Acute vessel occlusions are frequent in unselected patients. Occlusions occurred in all NIHSS score values but a NIHSS cut-off value of 6 most optimally predicted acute vessel occlusion, even though accuracy was low.

Vascular pathology in the extracranial vertebral arteries in patients with acute ischemic stroke.

INTRODUCTION: Vascular pathology in the extracranial vertebral arteries remains among the possible causes in cryptogenic stroke. However, the diagnosis is challenged by the great variety in the anatomy of the vertebral arteries, clinical symptoms and difficulties in the radiological assessments. The aim of this study was to assess the prevalence of CT angiography (CTA)-detected pathological findings in the extracranial vertebral arteries in an acute stroke population and secondly to determine the frequency of posterior pathology as probable cause in patients with otherwise cryptogenic stroke. METHOD: The analysis was based on 657 consecutive patients with symptoms of acute stroke and a final diagnosis of ischemic stroke or transient ischemic attack. On admission, a noncontrast CT cerebrum and CTA were performed. A senior consultant neuroradiologist, blinded to clinical data, reviewed all CTA scans systematically, assessing the four segments of the extracranial vertebral arteries. First, the frequency of pathological findings including stenosis, plaques, dissection, kinked artery and coiling was assessed. Subsequently, we explored the extent of the pathological findings that were the most plausible causes of stroke, namely either a possible dissection or a kinked artery. RESULTS: Findings in the extracranial vertebral arteries included significant stenosis (0.8%), atherosclerotic plaque types (3.8%), possible dissections (2.6%), kinked arteries (2.6%) and coiling (32.0%). Eighteen patients (2.8%) with pathological findings had an unknown cause of stroke, likely posterior symptoms and no clinical stroke symptoms from the anterior circuit. Of these, 3 cases were kinked arteries (0.5%) and 15 cases (2.3%) were possible dissections. CONCLUSION: We found that in approximately 3% of the study population, the most plausible cause of the cryptogenic strokes was due to a pathological finding in the posterior extracranial vertebral arteries, being either a possible dissection or a kinked artery. In general, posterior vascular pathology is not uncommon, and CTA is a useful modality in the detection of changes based on characteristics and locations of findings in the extracranial vertebral arteries. Ultrasound examination can be a useful supplementary tool in deciding the consequence of vascular findings on CTA.