Internal carotid artery mainly of historical significance. The segments of the internal carotid artery are as follows: The internal carotid artery is a terminal branch of the common carotid artery; it arises around the level of the fourth cervical vertebra when the common carotid bifurcates into this artery and its more superficial counterpart, the external carotid artery. The cervical segment, or C1, or cervical part of the internal carotid, extends from the carotid bifurcation until it enters the carotid canal in the skull anterior to the jugular foramen. At its origin, the internal carotid artery is somewhat dilated. This part of the artery
Carotid sinus the carotid sinus reflex when pressure builds in one or both carotid sinuses. Stimulation of baroreceptors at the carotid sinus can be used to treat resistant hypertension via activation of the baroreflex. A pacemaker-like device can be implanted to electrically stimulate the receptors chronically, which is found to lower blood pressure by 15-25 mmHg. Massage of the carotid sinus, carotid sinus massage is used to diagnose carotid sinus syncope and is sometimes useful for differentiating supraventricular tachycardia (SVT) from ventricular tachycardia. Like the valsalva maneuver, it is a therapy for SVT. It is less effective than pharmaceutical management of SVT