gms | German Medical Science

Objective: Intracranial aneurysms (IAs) can present in association with Moyamoya Disease (MMD). Besides having the well-known risks of Moyamoya-caused ischemic or hemorrhagic strokes, patients with additional aneurysms are at risk of subarachnoid hemorrhage and its related complications.

Method: We report two cases with the combined symptomatic pathology of MMD and IAs out of 25 adult moyamoya patients treated in our department in the last 4 years. One 47yo female patient became symptomatic with a subarachnoid hemorrhage (SAH) Hunt and Hess grade 2, Fisher grade 4 caused by one of four identified intracranial aneurysms. The other patient, a 46yo male became symptomatic by a right sided intracranial hemorrhage (ICH) caused by fragile Moyamoya collaterals. Angiography revealed an incidental aneurysm of the right sided vertebral.

Results: Initial angiography imaging after SAH of patient 1 did not only show 4 IAs (left ICA, right PCA, 2x left PCA) of which three were coil-embolized, but also a total occlusion of the right-sided, as well as a subtotal occlusion of the left sided ICAs with Moyamoya-like collaterals. On day 4 after SAH the patient developed cerebral vasospasms which were treated by eight days of continuous intraarterial nimodipine application (0,4mg/h) in the left ICA and VA. No complications by the first-time reported use of continuous intraarterial nimodipine in a patient with Moyamoya were noticed and the patient recovered without suffering any new neurological deficits. Six months after the SAH, successful bilateral STA-MCA revascularization was performed. The second patient suffered a right-sided basal-ganglia ICH caused by fragile Moyamoya collaterals. Besides typical Moyamoya findings, angiography revealed a VA/PICA aneurysm on the right side, which was clipped microsurgically without any complications. Perfusion imaging with Diamox-challenge revealed an insufficient cerebral perfusion reserve-capacity in both MCA territories. Bilateral STA-MCA was planned as a second step.

Conclusions: The incidence of IAs in our adult moyamoya series is 8%. This percentage rate is distinctly higher than the risk in the general population and probably reflects both the hemodynamic stress and the inflammatory process as contributing factors. Combination of intracranial aneuryms and moyamoya disease is reiterated. Staged interdisciplinary treatment of both distinct pathologies and their respective complications is emphasized for the successful treatment.