Cerebrovascular diseases
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Cerebrovascular diseases · Jan 2011
Randomized Controlled TrialCilostazol improves outcome after subarachnoid hemorrhage: a preliminary report.
Cerebral vasospasm (VS) is the most common cause of morbidity and mortality after aneurysmal subarachnoid hemorrhage (SAH). Reversal of VS by intra-arterial infusion of cyclic adenosine monophosphate (cAMP)-elevating agents has been reported; however, the preventive role in the development of VS is not fully understood. This study is designed to evaluate the possible efficacy of using cilostazol, a selective inhibitor of phosphodiesterase type 3 and a cAMP-elevating agent, in patients with SAH. ⋯ Cilostazol may improve outcomes after SAH, but further double-blind, placebo-controlled studies are required for a definitive conclusion.
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Cerebrovascular diseases · Jan 2011
Comparative StudyChanges in cerebral perfusion around the time of delayed cerebral ischemia in subarachnoid hemorrhage patients.
Because the pathogenesis of delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH) is unclear, we studied cerebral perfusion at different time points around the occurrence of DCI. ⋯ Our findings suggest that DCI patients already have diffusely worse perfusion (absolute values) than no-DCI patients before focal worsening (increased asymmetry) occurs and becomes symptomatic. The partial recovery in the measured areas suggests that DCI can be partly reversible.
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Cerebrovascular diseases · Jan 2011
Comparative StudyDifferences in diffusion-weighted image and transesophageal echocardiographical findings in cardiogenic, paradoxical and aortogenic brain embolism.
The purpose of the present study was to clarify the difference in the infarct topography on diffusion-weighted image (DWI) and cardiac and aortic findings on transesophageal echocardiography (TEE) in stroke patients with different embolic sources. ⋯ Embolic stroke patients often have multiple embolic sources. The present study suggests the possibility that embolic stroke has unique clinical features depending on its source. DWI and TEE findings might be helpful in characterizing cardiogenic, paradoxical and aortogenic brain embolism.
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Cerebrovascular diseases · Jan 2011
Review Historical ArticleThe ischemic penumbra: correlates in imaging and implications for treatment of ischemic stroke. The Johann Jacob Wepfer award 2011.
The concept of the ischemic penumbra was formulated 30 years ago based on experiments in animal models showing functional impairment and electrophysiological disturbances with decreasing flow to the brain below defined values (the threshold for function) and irreversible tissue damage with the blood supply further decreased (the threshold for infarction). The perfusion range between these thresholds was termed 'penumbra', and restitution of flow above the functional threshold was able to reverse the deficits without permanent damage. However, in further experiments, the dependency of the development of irreversible lesions on the interaction of the severity and duration of critically reduced blood flow was established - proving that the lower the flow, the shorter the time for efficient reperfusion. ⋯ Some of these discrepancies can be explained by unselective application of relative perfusion thresholds, which might be improved by more complex analytical procedures. Heterogeneity of the MRI signatures used for the definition of the mismatch are also responsible for disappointing results in the application of PW/DW-MRI for the selection of patients for clinical trials. As long as a validation of the mismatch selection paradigm is lacking, its use as a surrogate marker of outcome is limited.