Table 1.

Cho Classification for peripheral arteriovenous malformations (AVMs).

Type of AVMs	Angiographic manifestations
Ⅰ	Arteriovenous fistula with three or less feeding arteries and a single draining vein.
Ⅱ a	Multiple arterioles shunt to the focal segment of the single draining vein
Ⅱ b	Multiple arterioles shunt to the venous sac with multiple draining veins
Ⅱ c	Multiple arterioles shunt along the long segment of the draining vein
Ⅲ a	Multiple arterioles shunt to multiple draining veins through multiple fine fistulae
Ⅲ b	Multiple arterioles shunt to multiple draining veins through multiple enlarged fistulae