Subclavian artery to external carotid artery bypass graft. Improvement of cerebral blood supply.

External carotid flow may contribute a substantial amount of cerebral flow via collaterals in cases of internal carotid artery occlusion. When common and internal carotid arteries are occluded, the distal portion of the external carotid artery is kept open by collateral flow. Revascularization of the external carotid by means of a bypass graft from the subclavian artery will improve the blood flow through collateral vessels connecting the external and internal carotid territories, and thus increase the cerebral blood supply from the branches of the external carotid artery.