Incidence and neurological significance of postoperative cerebral vasospasm. A study of 80 consecutive cases with clipped saccular aneurysms.

Abstract

The pre- and postoperative angiograms of 80 patients with clipped cerebral aneurysms were reviewed and vasospasm was classified, according to the extent of the angiospasm, into three types (type I diffuse, widespread spasm, type II multisegmental vasoconstriction, type III local angiospasm). The neurological Status of the patients at the time of angiography and Operation was correlated with the clinical grading System of Hunt and Hess. Postoperative vasospasm was found in 40% of the cases. There was a remarkably close correlation between the incidence of severe spasm (type I) and the time which had elapsed from haemorrhage to Operation: Almost all patients who developed diffuse extensive angiospasm after Operation (most of them had no pre-operative spasm or only minor, initially local, vasoconstriction) had been operated on within the first eight days after subarachnoid haemorrhage. Those cases which had angiospasm pre-operatively but no longer had vasospasm after Operation had all undergone Operation later than the first week. Patients with local or multisegmental angiospasm are more often grade III or IV within the first week than patients with equal spasm postoperatively two or three weeks after initial SAH. This suggests that in the early phase after rupture of an aneurysm factors other than local vasoconstriction per se must play a pathogenetic role. These factors have no influence or only a minor significance in the later weeks.