Introduction: The natural courses and prognosis of Moyamoya disease (MMD)-related aneurysms are not well-known. The purpose of this study is to address the single institution’s experience about treatment outcomes of MMD–related aneurysms.
Methods: From January 1995 to December 2015, a total of 599 patients has been diagnosed and treated as MMD at single institution. 32 patients (5.3 %) with 42 aneurysms were identified. Excluding follow-up loss, 26 patients with 35 aneurysms were enrolled in this study. These lesions were classified into two groups (A: major artery aneurysms, B: non-major artery aneurysms) according to the location of parent artery. We investigated the characteristics and treatment outcomes of MMD-related aneurysms by a retrospective review of Electronic Medical Record.
Results: Among 35 aneurysms including 10 ruptured lesions, there were 21 (60 %) in group A and 14 (40 %) in group B, respectively. The average size of aneurysms was 4.0 mm in group A and 3.4 mm in group B. The most common location was a basilar artery (n = 8, 38.1 %) and a posterior choroidal artery (n = 7, 46.7 %). Four aneurysms were treated at the time of diagnosis and the rest 18 aneurysms in group A and 13 aneurysms in group B were treated conservatively and followed up (mean 59 months). In group A, 14 lesions (77.8 %) were stable, while 4 lesions (22.2 %) grew and treated by endovascular coiling. In group B, 10 lesions (92.3 %) were stable, while 3 lesions (7.7 %) progressed or ruptured. During the follow-up, additional 5 aneurysms were treated. 9 cases were successfully treated by endovascular method (7 in group A, 2 in group B) with one case of procedure-related complication (11.1 %).
Conclusions: MMD-related aneurysms have a considerable rate of growing or bleeding (22.6%. In a selected case, endovascular technique can be a solution.
Patient Care: Cerebral aneurysm in patients with Moyamoya disease (MMD) should be treated more aggrassively than those in non-MMD patients, and followed up more frequently.
Learning Objectives: To characterize cerebral aneurysm associated with Moyamoya disease, as they seem to have worse prognosis.