Common Carotid Flow During Graded Stenosis and Occlusion of the Internal Carotid Artery

Since the introduction of the Doppler ultrasonic transcutaneous flow detector, a host of simplified procedures have been proposed for use in evaluating the resistance, percentage lumen decrease and reduction in flow through the internal carotid artery. These methods generally use information derived from the cervical carotid and/or the ophthalmic branches. One method currently in use employs the relationship between the diastolic and systolic velocities of blood flow in the common carotid artery, as measured with the Doppler flowmeter, to estimate vascular resistance in the carotid system.(3)