Temporal profile of angiographical stages of moyamoya disease: when does moyamoya disease progress?

To elucidate the initiation of Moyamoya disease, we analyzed the progression of angiographical stages in repeated angiographical studies. The clinical subjects consisted of 39 patients. Angiographical stages were classified by the criteria of Suzuki and Takaku. For examinations, conventional cerebral angiography or magnetic resonance angiography was performed. The follow-up period ranged from three months to 17 years. We found the following results. 1. Older patients presented with advanced angiographical stages. 2. Angiographical stages were usually progressive in pediatric patients, while stable in adult patients. In pediatric cases, the disease advanced to stage V within 10 years from the onset in the majority of patients. However, in certain cases the disease progressed after adolescence. 3. Among pediatric patients, certain cases, in whom the onset of the disease was later than five years of age, showed relatively slow progression of angiographical stages. Our data indicate that certain pediatric cases whose disease started after five years of age presented with stable temporal changes in the angiographical stages. These findings might indicate that in only a few adult cases does the disease initiate in adulthood and in the majority of adult patients the disease starts in childhood.