Introduction: Moyamoya disease was first believed to be confined to Japan, but over the years it has been reported all over the world. We report seven cases from the University Hospital of the Faculty of Medicine of Ribeirão Preto, University of São Paulo with a review of the previously described cases in Brazil.
Material and methods: The diagnosis was based on the diagnostic criteria of the Research Committee on Spontaneous Occlusion of the Circle of Willis.
Results: Five patients presented ischemic and two hemorrhagic events. The meta-analysis of the six cases previously described in Brazil showed that only two were true moyamoya disease according to the diagnostic criteria.
Conclusion: We can assume that the real frequency of moyamoya disease has been underestimated in Brazil.