Acute MRI Findings in Young Children with Moyamoya Disease

Abstract

ObjectiveTo describe the diffusion-weighted imaging (DWI) findings in young children with Moyamoya disease (MMD) during the acute period of the condition. MethodsClinical data were collected from 12 children with MMD < 6 years of age, in whom abnormalities were observed on DWI scans obtained within 1 week after the appearance of symptoms related to MMD. The DWI abnormalities were classified into gyral, atypical territorial, honeycomb, classical territorial, multiple-dot, border zone, and deep lacunar patterns. The severity of arterial stenosis was graded by angiographic stages that have been previously described. ResultsIn all but one child, the DWI abnormalities were restricted to the cerebral cortex. The lesions were gyral in nature in seven children and atypical territorial in five; all differed from those of typical arterial strokes. Internal carotid artery stenosis was observed in all 12 children, although the stenosis was mild in 11. The severity of arterial stenosis did not match the regions of ischemic lesions in some children. There was no statistically significant difference in the severity of arterial stenosis according to the presence or absence of ischemic lesions or the pattern of the lesions. ConclusionsLesions located mainly in the cerebral cortex, i.e., not in arterial territories, are characteristic of young children with MMD.