Unilateral Moyamoya Phenomenon Due to MCA Occlusion in a Child Presenting with Intracerebral Hemorrhage.

SUMMARY: Spontaneous middle cerebral artery (MCA) occlusion leading to moyamoya phenomenon is different from classical moyamoya disease. Previous studies have reported such phenomena in adults with ischemic lesions, except for a solitary case in a child.We report a case of a ten-year old girl who presented with a deep intracerebral hematoma and a normal ipsilateral middle cerebral artery on initial evaluation by CT. Subsequently, on follow-up angiography, the ipsilateral MCA was occluded with evidence of unilateral basal lenticulostriate and transdural collateral supply causing a 'moyamoya' phenomenon. This report discusses a rare and interesting disease from the perspective of 'moyamoya' phenomenon and angiogenesis.