Twenty-two,patients,of,acute,cerebral,revascularization,were,analyzed,in,order,to,evaluate,various,predictors related to surgical effectiveness and outcome. These patients presented sudden neurological symptoms following occlusion of the middle cerebral artery (MCA). The left MCA was involved in 8 patients, and the right in 14 patients. Prior to surgical intervention, CT scan, serial angiography, and measurement of cerebral blood flow (CBF) were performed. STA-MCA anastomosis was completed in 21 patients, and left MCA embolectomy was performed on one patient. In the 14 patients of the effective group, the time elapsed from onset of stroke to revascularization was an average of 19.5 hours (6-72 hours). Of these patients,7 cases has a residual CBF of 24.8±1.2m1/100g/min (45% of normal CBF). Collateral flow, as judged from the preoperative angiograms, was good in 4 cases, and fair in 10 cases. In the 8 cases of the non-effective group, the time elapsed prior to the restoration of flow was an average of 8.2 hours (6-16 hours). Three cases had a residual CBF of 19.5 ±1.1m//100g/min. Collateral flow was fair in 5 cases, and poor in 3 cases. These results suggest that good preoperative collateral flow and residual CBF constitute the most accurate favorable predictors for the estimation of surgical effectiveness and outcome, and the time limits for acute cerebral revascularization is variable according to the degree of residual CBF supplied by collateral flow patterns
