Long-term Outcoune in Patients with Intracranial Arterial Dissection and Subarachnoid Hemorrhage: Analysis of 25 Conservatively Managed Patients in Vertebrobasilar System.

The natural history of intracranial arterial dissection is not well known yet, so that adequate treatment is still controversial for this disease. We conducted this study to elucidate the clinical features and the long-term outcome of the conservatively managed patients with the intracranial arterial dissection and subarachnoid hemorrhage in the vertebrobasilar system. Twenty-five patients were conservatively managed (only control of high blood pressure, no antiplatelet nor anticoagulant), whereas 64 underwent surgery, including intravascular surgery. The reasons for the conservative treatment were: anatomical problems in 11, poor clinical state in 9, and treatment strategy in 5. In the retrospective analysis, age, clinical severity, location of the dissection, and angiographical findings did not differ between the 2 groups. The incidence of the history of arterial hypertension and the rate of rebleeding were significantly higher in the conservative group. In the conservative group, the follow-up period ranged from 0.5 to 14 years (mean=6.4 years). The most common finding on serial angiogram was no change on the initial one, followed by improvement. As for outcome, 13 patients died of rebleeding or vasospasm in the acute stage. The long-term outcome in the remaining 12 was favorable: Eleven made good recovery. These results suggest that the long-term outcome in the ruptured vertebrobasilar arterial dissection might be favorable, if the patients overcome the various problems in the acute stage.