Cerebrovascular diseases
-
Cerebrovascular diseases · Jan 2012
Hyperintensity of distal vessels on FLAIR is associated with slow progression of the infarction in acute ischemic stroke.
Hyperintensity of distal vessels on FLAIR-MRI has been associated with a higher grade of arterial collaterals and a smaller infarct volume in acute stroke patients. No studies analyze the influence of the hyperintense vessel (HV) sign on the speed of the ischemia progression during the first hours. Our aim was to study the association of the HV sign with progression of infarction in acute stroke patients. ⋯ HV sign on FLAIR, especially if prominent, is associated with a slow progression of the ischemic area in acute stroke patients with cerebral artery occlusion of the anterior circulation. This radiological sign may predict the speed of the ischemia progression, opening an opportunity for reperfusion therapies in longer time windows.
-
Cerebrovascular diseases · Jan 2012
Significance of good collateral compensation in symptomatic intracranial atherosclerosis.
Collateral circulation stabilizes cerebral blood flow in patients with acute occlusion, but its prognostic role is less studied in intracranial atherosclerosis and appears different in moderate to severe stenosis. We aimed to study the associations between antegrade flow across stenosis, collateral flow via leptomeningeal anastomosis, and the neurological outcome and recurrence risk in patients with symptomatic intracranial stenosis. ⋯ Good collateral compensations are more important in patients with symptomatic intracranial stenosis and compromised antegrade flow, and are associated with favorable outcome and less recurrence risk. The feasibility of composite flow assessment should be explored in future studies to identify high-risk intracranial stenosis with compromised hemodynamics.
-
Cerebrovascular diseases · Jan 2012
Cerebrospinal fluid catecholamine levels as predictors of outcome in subarachnoid hemorrhage.
Subarachnoid hemorrhage (SAH) is associated with marked sympathetic activation at the time of ictus. The purpose of this study is to determine whether early central catecholamine levels measured from cerebrospinal fluid (CSF) relate to outcome in patients with SAH. ⋯ CSF catecholamine levels are elevated in SAH patients who experience early mortality or disability. EPI may potentially serve as useful index of outcome in this population of patients with SAH.
-
Cerebrovascular diseases · Jan 2012
Persistence of hyperdense middle cerebral artery sign on follow-up CT scan after intravenous thrombolysis is associated with poor outcome.
The rates and extent of recovery in acute ischemic stroke (AIS) patients treated with intravenous tissue plasminogen activator (IV-tPA) remain highly variable. Hyperdense middle cerebral artery sign (HMCAS) on pretreatment unenhanced computerized tomography (CT) of the brain represents the presence of thrombus, often associated with severe neurological deficits and poor clinical outcome at 3 months. However, HMCAS is reliable only in AIS patients managed conservatively. In patients treated with systemic thrombolysis, HMCAS may disappear (representing clot dissolution) or persist (persisting clot) on the follow-up CT scan of the brain. We aimed at evaluating whether disappearance or the persistence of HMCAS on follow-up CT scan of the brain can predict the final outcome at 3 months. ⋯ Persistence of HMCAS on the follow-up CT scan of the brain in acute ischemic stroke patients treated with IV-tPA can be used as an early predictor of poor functional outcome.
-
Cerebrovascular diseases · Jan 2012
Case ReportsLocal hemodynamics at the rupture point of cerebral aneurysms determined by computational fluid dynamics analysis.
Cerebral aneurysms carry a high risk of rupture and so present a major threat to the patient's life. Accurate criteria for predicting aneurysm rupture are important for therapeutic decision-making, and some clinical and morphological factors may help to predict the risk for rupture of unruptured aneurysms, such as sex, size and location. Hemodynamic forces are considered to be key in the natural history of cerebral aneurysms, but the effect on aneurysm rupture is uncertain, and whether low or high wall shear stress (WSS) is the most critical in promoting rupture remains extremely controversial. This study investigated the local hemodynamic features at the aneurysm rupture point. ⋯ The hemodynamics of 6 ruptured cerebral aneurysms of the middle cerebral artery were examined using retrospective CFD analysis. We could confirm the rupture points in all cases. With those findings, local hemodynamics of ruptured aneurysms were quanti-tatively investigated. The rupture point is located in a low WSS region of the aneurysm wall. Bleb-removed simulation showed increased WSS of the bleb-removed area, associated with the flow impaction area. Although the number of subjects in this study was relatively small, our findings suggest that the location of the rupture point is related to a low WSS at the aneurysm wall. Further investigations will elucidate the detailed hemodynamic effects on aneurysm rupture.