Distinct clinical and radiographic characteristics of moyamoya disease amongst European Caucasians

Background and purpose Occlusive cerebrovascular moyamoya disease (MMD) is rare and has been characterized mainly in Asian countries, so far. In recent years, MMD has been increasingly reported worldwide, raising the question whether its clinical presentation would vary amongst different ethnic backgrounds. Here, a homogeneous series of 153 patients with MMD are reported and the specific clinical features of this rare disease amongst European Caucasians are highlighted. Methods A total of 153 European Caucasians with MMD who were treated in our institution between 1997 and 2014 were retrospectively identified. Demographic data, clinical symptoms, angiographic characteristics and functional hemodynamic studies were analyzed. Results Moyamoya disease presented with a female predominance of 2,9:1.,78% presented with a typical MMD, 17% with a unilateral MMD and 5% with an atypical MMD. 16% of our patients belonged to the pediatric population. Overall, 81% and 8.5% of our cohort presented initially with ischaemic and hemorrhagic manifestation, respectively. The rate of hemorrhagic manifestation of MMD amongst the pediatric group was slightly higher (12%). Angiographic analysis revealed steno‐occlusive involvement of the posterior circulation in 34% with a higher involvement in pediatric patients (64%) compared to adults (28%). Conclusions The characterization of our homogeneous European Caucasian cohort reveals several significant differences compared to Asian cohorts. In contrast, MMD presents similarly amongst European and North American cohorts, suggesting that non‐Asian MMD is characterized by distinct clinical features.