Endoscopic coagulation of nasal blood vessels
In some centres, radiologists use embolisation to control nasal bleeding. During arteriography (in which dye is injected into the carotid system) a catheter is introduced into the carotid-artery system until the vessel giving rise to the bleeding (usually a branch of the external carotid) can be visualised by dye injection. The artery is then selectively embolised by injection of particulate matter (usually gelfoam) which obstructs it and causes thrombosis. The technique is strongly advocated by a small number of radiologists, but most centres do not have access to it. There are risks of embolising unselected vessels. The consequence of inadvertently embolising a branch of the internal carotid supplying the brain would be a stroke.