[Ultrasonic noninvasive examination of the human cerebrovascular system using the vascular impedance method].

The authors employed input vascular impedance measurements, based on the non-invasive ultrasound measurements of blood flow and pressure in common carotid artery, to evaluate human cerebro-vascular system. An analysis involved a 4-element substitute model of vascular system which included: compliance, inertia, vascular resistance, and peripheral resistance. Preliminary clinical examination of both sick and healthy individuals indicate that total real resistance measured in the common carotid artery depends on the patency of branching arteries. At the same time, ratio of vascular resistance Ro do peripheral resistance Rp may be an indicator of the atheromatous lesions to the arteries below measurement point. Ratio Ro greater than 0.5 is being considered as an index of pathology.