Objective: Previous reports have described an association between moyamoya disease and arteriovenous malformations, but this unusual case is the first report of a unilateral moyamoya pattern simultaneously associated with an ipsilateral dural arteriovenous fistula (dAVF).
Clinical presentation: A 44-year-old man presented with headache, tinnitus, and an intraventricular hemorrhage, as seen on computed tomographic scans. Cerebral angiography showed a right moyamoya pattern and an ipsilateral dAVF fed by branches of the external carotid artery and draining into the transverse sinus.
Intervention: After the intraventricular hemorrhage resolved, the patient underwent transarterial embolization of the dAVF with Onyx (EV3, Inc. Irvine, CA), followed by a direct superficial temporal artery-to-middle cerebral artery bypass. Subsequent reconstitution of the dAVF required transvenous embolization, which obliterated the dAVF. At his 2-month follow-up examination, the patient was asymptomatic and neurologically intact.
Conclusion: Recent investigations have established that both moyamoya disease and dAVFs are associated with dural angiogenesis. These factors may represent a mechanism for vaso-occlusive ischemia contributing to the formation of dAVF. This extremely rare coincidental presentation may have deeper pathogenic implications.