Moya Moya Disease:

It is a rare, progressive cerebrovascular disorder characterized by the narrowing or occlusion of major blood vessels leading into the brain, and the formation of abnormal blood vessels called moyamoya vessels. (ie "puff of smoke") characterizes the appearance on angiography of abnormal vascular collateral networks that develop adjacent to the stenotic vessels. The steno-occlusive areas are usually bilateral, but unilateral involvement does not exclude the diagnosis. Cerebral angiography in this case has shown poorly opacified intracranial internal carotid artery and its branches. The CT Scan shows multiple infarcts in bilateral cerebral hemisphere new and old.