Introduction: : Despite being the most common presentation in pediatric moyamoya patients, TIA in children has rarely been described. The clinical features and risk factors for stroke of these TIAs remain unclear. The aim of the study is to describe the clinical characteristics of the TIA in moyamoya children and study risk factors associated with stroke after TIA.

Methods: We searched the moyamoya database of our stroke center for children with initial presentation of TIA from January 2011 to August 2015. TIA characteristics were summarized. Risk factors for subsequent stroke were analyzed using time-to-event analyses.

Results: We identified 60 pediatric moyamoya patients with TIA from 693 moyamoya vasculopathy patients referred to our hospital between 2011 and 2015. The mean age of initial presentation was 10.0 ± 3.5 years. Motor weakness (n=51, [85%]) was the most common symptom in our cohort. Nearly all patients (n=55, [91.7%]) had recurrent TIA during follow-up. Subsequent strokes were observed in 14 patients (23.3%) during follow-up. We identified prolonged duration for recurrent TIA (HR, 3.61; 95% CI, 1.17-11.17; P=0.03) as an independent risk factor for future strokes.

Conclusions: We observed several differences in clinical characteristics of TIA in moyamoya children comparing to adults or children with TIA of various etiology. We identified prolonged duration for recurrent TIA as an independent risk factor for future strokes.

Patient Care: We provided evidence that prolonged episode of recurrent TIA as a risk factor for future stroke event, which could translate into useful clinical information in counselling for the timing of revascularization

Learning Objectives: By the conclusion of this session, participants should be able to have a better knowledge of TIA in pediatric moyamoya patients and Identify when and if to perform revascularization for these patients.

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