Common carotid artery the common carotid artery ascends in the neck without any subdivision, either the external or the internal carotid being absent; and in a few cases the common carotid has itself been found to be absent, the external and internal carotids arising directly from the arch of the aorta. This peculiarity existed on both sides in some instances, on one side in others. The common carotid usually gives off no branch previous to its bifurcation, but it occasionally gives origin to the superior thyroid artery or its laryngeal branch, the ascending pharyngeal artery, the inferior thyroid artery, or, more rarely, the
Carotid sinus blood vessels. The aortic arch baroreceptors are innervated by the aortic nerve (Nerve of Cyon), which combines with CN X (vagus nerve) and travels to the NTS. It is a sensitive site of the body because stimulation can drive large-scale reflex effects throughout the body. This can be used therapeutically in treatment of resistant hypertension by baroreflex activation. Physical assault at this point, producing massive baroreflex activation can cause dramatic falls in blood pressure and cerebral ischemia. The carotid sinus often has atherosclerotic plaques because of disturbed hemodynamics (low wall shear stress, flow reversal/recirculation). Since these plaques, if large and