The outcome of the acute subdural hematoma

Thirty-five cases of acute subdural hematoma (ASDH) were reviewed and divided into two groups of A and B according to the outcome. The findings of computed tomography (CT) and the time interval between head trauma and surgical intervention were investigated to know the factors that influence the prognosis in ASDH. Group A, 18 patients, had a poor outcome. Fifteen patients out of 18 had the removal of hematoma and decompression craniectomy with 10 deaths, 4 vegetative states and 1 severe disability. Three patients died without surgery. Group B, 17 patients, were treated surgically in the same way as in group A and all patients had a good recovery with 14 making a full recovery and 3 with a moderate disability. Surgical mortality was 31.3% and overall mortality was 37.1%. The features of the CT findings in 18 patients of group A were as follows. Eleven patients had midline shift of more than 15 mm, 9 had subdural high density area of more than 15 mm and 12 patients had bilateral collapse of the lateral ventricles. The charactaristic finding of CT recognized in all patients of group A was disappearance of the ambient cistern. On the contrary, in 17 patients of group B the displacement of the intracranial structure was not so severe as in group A. The midline shift of 14 patients was less than 7.5 mm, the width of subdural high density area of 15 patients was less than 7.5 mm and the ambient cistern was recognized in 12 patients. For 11 patients out of 15 in group A, the operation was performed within 6 hours following the onset of head trauma, however, 9 patients died, one in a vegetative state and one had severe disability postoperatively. Thirteen patients out of 17 in group B were operated on later than 6 hours after the onset of the head trauma, and yet took a good outcome. (J.P.N.)