Over a period of 28 months, 29 patients who sustained uncal herniation originating from fronto-temporal acute subdural hematoma with major contusion and swelling of the temporal lobe were treated surgically. These 29 patients were divided into two groups according to whether or not they underwent aggressive temporal resection in two study periods. During the initial 16 months, from February 1991 to June 1992, 16 of the 29 (group A) underwent classic surgery (subtemporal decompression for evacuation of the hematoma and debridement of the contused brain). In the 12 months from July 1992 to June 1993, the remaining 13 patients (group B) underwent an aggressive temporal lobectomy in addition to the afore-mentioned procedures, including 10 complete temporal lobectomies and three anterior temporal lobectomies. In group A, there were nine operative deaths, with a mortality of 56%, and the mean Glasgow Outcome Scale (GOS) score was 2.2 +/- 0.4 (mean +/- SEM) after 24 to 36 months of follow-up. In group B, one patient died after operation, and the mean GOS score was 4.0 +/- 0.4 in a follow-up period of 12 to 24 months. Compared with group A, group B showed a better survival rate and more favorable functional outcome. Favorable recovery in group B was noted only after a complete temporal lobectomy (good in seven and moderate disability in three). The three patients who underwent an anterior temporal lobectomy had unfavorable recoveries (two vegetative states and one death).(ABSTRACT TRUNCATED AT 250 WORDS)