Decompressive craniectomy, reperfusion, or a combination for early treatment of acute "malignant" cerebral hemispheric stroke in rats? Potential mechanisms studied by MRI

Background and Purpose-Both early reperfusion and decompressive craniectomy have proved beneficial in the treatment of large space-occupying "malignan t" hemispheric stroke. The aim of this study was to directly compare the be nefit of reperfusion with that of craniectomy and to study the effects of c ombined treatment in a rat model of focal cerebral ischemia. Methods-Cerebral ischemia was introduced in 28 rats. Four groups were inves tigated: (1) no treatment, (2) decompressive craniectomy, (3) reperfusion, and (4) reperfusion and craniectomy as treatment at 1 hour after middle cer ebral artery occlusion. Perfusion- and diffusion-weighted MRI were performe d serially from 0.5 to 6 hours after middle cerebral artery occlusion. Results-The 6-hour DWI-derived hemispheric lesion volumes in the reperfusio n group (10.2+/-3.9%), the craniectomy group (23.0+/-6.4%), and the combina tion group (21.8+/-12.4) were significantly smaller than that in the contro l group (44.1+/-5.4%) (P<0.05), Reperfusion, craniectomy, and combined trea tment led to higher perfusion in the cortex compared with the control group , whereas only reperfused animals achieved significantly higher perfusion i n the basal ganglia. Ln 5 animals, combined reperfusion and decompressive c raniectomy resulted in an early contrast media enhancement. Conclusions-Early reperfusion and craniectomy were shown to be effective in decreasing infarction volume by improving cerebral perfusion. Reperfusion remains the best therapy in malignant hemispheric stroke. Combined treatmen t yields no additional benefit compared with single treatment, probably bec ause of early blood-brain barrier breakdown.