Abstract T P378: Factors Associated with the Presentation of Moyamoya in Childhood

Introduction: Moyamoya accounts for approximately one fifth of cerebral arteriopathies in children presenting with acute stroke, however often is not diagnosed until stroke occurs, even in higher risk populations and often despite a history of transient ischemic attacks (TIA’s). The surgical management and outcome are well reported, but limited information exists regarding signs and symptoms preceding diagnosis. This study was undertaken to better define which groups of children are at risk for moyamoya and how these children present. Methods: With IRB approval, the charts of all patients with a diagnosis of moyamoya cared for between Jan 1, 1997 - Sept 26, 2013 were reviewed. Results: Of 54 children with moyamoya, the mean age at presentation was 7 ½ years. 56% were female. 32 (59 %) had predisposing medical conditions associated with moyamoya. 17 (31%) were of Asian descent. Only 11 children (20%) had no underlying predisposing condition identified, of whom 4 had underlying conditions not previously reported in association with moyamoya. 8 patients (15%) were Native American. 38 (70%) had a history of transient ischemic attacks. 26 (48%) presented with acute stroke, of whom ¾ had left and ¼ had right hemisphere strokes. 52% had a history of headache. Discussion: The mean age and female predominance in this series are consistent with previous reports. Most children with moyamoya in this series had an underlying predisposing condition, compared with other US series, where almost half had no predisposing condition identified. 15% of children in this series are American Indian or Alaska Native, compared with 1.3% of all patients served at this institution. In this series, fewer children (48% vs 68%) presented with stroke, more (70% vs 43%) had a history of TIAs, and more (52% vs 22%) had a history of headaches than in previous reports. In addition, the Native American population may be at higher risk of moyamoya than previously recognized.