Fig. 7From: Four collateral circulation pathways were observed after common carotid artery occlusionCTA discovered a fourth collateral circulation pathway that supplied ipsilateral ICA after CCAO. CTA showed coexistence of several collateral circulation pathways in one patient. Pathway 1: ipsilateral vertebral artery – occipital artery (arrow ①) – ECA – ICA. Pathway 2a: ipsilateral thyrocervical trunk – ascending cervical artery (arrow②) – occipital artery – ECA – ICA. Pathway 2b: ipsilateral costocervical trunk – deep cervical artery (arrow ③) – occipital artery – ECA – ICA. Pathway 4: ipsilateral thyrocervical trunk – inferior thyroid artery – superior thyroid artery (arrow ④) – ECA – ICABack to article page