Table 3:

The stages of basal Moyamoya vessels

Stages	Angiographic Findings
I	No Moyamoya vessels were seen
II	Moyamoya vessels were localized in the area around the ICA bifurcation, and each vessel was fine and had little contrast
III	Moyamoya vessels had intermediate extension and thickness
IV	Moyamoya vessels extended a great deal, and each one was thick and strongly opacified

Note:—ICA indicates internal carotid artery.