Blood pressure reduction in the first 24 hours of stroke onset is independently associated with poor outcome after 3 months.

Background and Purpose-Although white matter is a potential target of acute stroke therapy, there is uncertainty about its relative resistance to ischemia and whether it is capable of mounting a penumbral response. To explore these issues further, we examined the differential effects of ischemia on gray and white matter using magnetic resonance (MR) perfusion-diffusion mismatch after acute stroke. Methods-MR imaging studies were performed within 12 hours in patients with initial hemispheric ischemic stroke."At-risk" tissue was defined as tissue with abnormal diffusion-weighted imaging/perfusion-weight imaging or infarction on follow-up image. Tissue was segmented using a probabilistic atlas generated from age-matched controls. The proportions of "at-risk" tissue, which was penumbral at the time of imaging, were compared between gray and white matter. Results-Thirty-two patients had diffusion-perfusion mismatched penumbral tissue present in both gray and white matter compartments. Although the absolute mismatch volumes were greater in gray (median 42 cm 3 , interquartile range 18 to 70 cm 3 ) than in white matter (39 cm 3 , 17 to 49 cm 3 ; PϽ0.001), the proportion of "at-risk" tissue, which was penumbral at the time of imaging (median 3.7 hours, range 1.5 to 9.9 hours) was greater in white (69%, 49% to 86%) than gray matter (62%, 52% to 75%; Pϭ0.026). However, the proportions spontaneously salvaged by 3 months were similar in both compartments. Conclusions-These findings are consistent with white matter being able to mount an ischemic penumbral response in humans and being more resistant to cerebral ischemia than gray matter. They also raise the possibility that the therapeutic window is longer for white matter and may require alternative therapeutic strategies. (Stroke. 2005;36:2132-2137.)

Resumo -A hemorragia intraparenquimatosa cerebral (HIC) é o subtipo de AVC de pior prognóstico e com tratamento ainda controverso em diversos aspectos. O comitê executivo da Sociedade Brasileira de Doenças Cerebrovasculares, através de uma revisão ampla dos artigos publicados em revistas indexadas, elaborou sugestões e recomendações que são aqui descritas com suas respectivas classificações de níveis de evidência. Estas diretrizes foram elaboradas com o objetivo de prover o leitor de um racional para o manejo apropriado dos pacientes com HIC, baseado em evidências clínicas.PALAVRAS-CHAVE: hemorragia intraparenquimatosa cerebral, recomendações, tratamento. Brazilian guidelines for the manegement of intracerebral hemorrhageAbstract -Among the stroke subtypes, intracerebral hemorrhage (ICH) has the worst prognosis and still lacks a specific treatment. The present manuscript contains the Brazilian guidelines for the management of ICH. It was elaborated by the executive committee of the Brazilian Cerebrovascular Diseases Society and was based on a broad review of articles about the theme. The text aims to provide a rational for the management of patients with an acute ICH, with the diagnostic and therapeutic resources that are available in Brazil.