Abstract
362 cases of intracranial AVM were presented to analyze the incidence of intracranial bleeding after onset. Of these, 91 patients were treated conservatively, and then long time follow-up study was done on 80 patients until death or until May 1989 (mean follow-up time 9.9 years).
The incidence of bleeding among these 80 cases was analyzed according to age at onset, location and size of AVM, and initial symptoms. Only the initial symptoms were significantly related to the risk of bleeding after onset. The average yearly risk of re-bleeding in the hemorrhage onset group was 2.8%, and the same risk of first bleeding in the non-hemorrhage onset group was 1.2%.This finding is useful in deciding the treatment where a difficult operation is predicted.
