CAROTID ARTERY (Fr. earotide, Lat. camas, Gk. Kaporrts, karotis, carotid, from ncipos, karos, deep sleep). The great artery which on each side distributes blood to the different parts of the head. Each carotid artery consists of the primitive or common carotid, which, at the upper margin of the larynx, separates into two great divisions of nearly equal si•, the external and internal tarot id. The external carotid supplies the larnyx, tongue. face, and scalp with blood. its principal branches being the superior thyroid, the lingual, the facial, the occipital, the pos terior auricular, the internal maxillary, and the temporal. The internal carotid enters the cavity 01 the cranium through a somewhat tortuous canal in the temporal bone, and after perforating the dura water, or fibrous membrane of the brain, separates into the anterior and middle cerebral arteries, whit+ are the principal ar teries of the brain; while in its course through the dura nutter it gives off the ophthalmic artery, which subdivides into several small branches; that supply the eye and surrounding parts. Sec Cm Wounds of the carotid trunks are generally from stabs. Suicides have a vague desire to cut them, but rarely cut suffieiently deep by the side of the windpipe. Of eourse, should either vessel
be wounded. death would result almost imme diately. Punctured wi ntids. however, may not be immediately fatal; they may heal. or a false aneurism (q.v.) may result. These arteries are sometimes the seat of spontaneous or true aneurism. Sir .Astley Cooper was the first to tie the common carotid for spontaneous anew ristn, in 1905. and since then the operation has been successfully performed many times. Owing to the numerous interchanges of branches be vessels of both sides of the head, cutting 611' the supply of blood through one carotid is seldom followed by impairment of brain struc ture or function. The common carotid in the horse is the termination of the right arteria in nominata. It. is a large es-el about an inch long, which emerges from the chest below the windpipe, and divides into the right and left carotids. These bend upward. having the wind pipe between them gradually inclining inward at the upper part, where each divides into ex ternal and internal carotids. and a large anasto 'nosing branch arising from between these two. Consult Toldt, Anatomischer Atlas (Berlin and Vienna, 1900).