9-year-old male with moyamoya disease who presented with repeated episodes of transient left hemiparesis

(A) Noncontrast head CT scan shows low-density area of infarction in the right basal ganglia (arrow).

(B) MRI FLAIR image depicting a high-signal-intensity area in the right basal ganglia and multiple small hyperintense areas in both basal ganglia consistent with infarction.

(C, D) Selective intra-arterial DSA (anteroposterior projection) shows severe stenoses of the distal right and left internal carotid arteries. Abnormal network of blood vessels (puff of smoke or moyamoya vessels) in the vicinity of the stenotic areas were noted (arrows).