Abstract
The prognosis for intracranial hemorrhage associated with moyamoya disease is extremely poor. The objective of the Japan Adult Moyamoya (JAM) Trial, a multicentered prospective randomized controlled trial conducted by 22 institutions in Japan, was to test the hypothesis that extracranial-intracranial direct bypasses reduce the rebleeding risk in adult patients with moyamoya disease. Eighty adult patients with hemorrhagic moyamoya disease were allocated either to conservative care or to bilateral extracranial-intracranial direct bypass and observed for five years thereafter. The results of the JAM Trial strongly support the beneficial effect of direct bypass surgery for hemorrhagic moyamoya disease. Clinicians should, however, keep in mind that the results were achieved under very low complication rate and cannot be applied to indirect bypasses.
