ULTRASOUND DETERMINATION OF TOTAL ARTERIAL-WALL THICKNESS

Purpose: Ultrasonic measurement techniques for determining intima-medi a thickness and total arterial wall thickness have been described. The intima-media thickness measurements are currently in use in large epi demiologic trials. Intima-media thickness does not evaluate extramedia l atherosclerotic change and so may not fully reflect pathologic chang es in the arterial wall. Methods: After we performed variability studi es of B-mode image acquisition and measurement, we measured total wall thickness and intima-media thickness of the common carotid arteries i n 60 adult subjects in three groups: a control group aged 20 to 29 yea rs, a control group aged 60 to 79 years, and a claudication group aged 60 to 79 years. Measurements were made with B-mode ultrasound images. Results: No statistical difference between sexes was noted. A statist ically significant (p less than or equal to 0.05) increase in intima-m edia thickness and wall thickness was found with increasing age, and a n additional increase was observed with clinically significant lower e xtremity arterial occlusive disease (p less than or equal to 0.05). Im age quality had an effect on measurement accuracy. Conclusions: The fi nding that the wall thickness of common carotid arteries is increased in those patients with clinically significant lower extremity disease supports the theory that atherosclerosis affects the arterial wall in a systemic fashion. Because intima-media thickness also increases acro ss subject groups without change in its proportional contribution to t he total arterial wall thickness, extramedial arterial changes also oc cur with aging and the development of atherosclerosis. We propose that because increases in wall thickness measurements of common carotid ar teries follow intima-media thickness increases (but do not necessarily measure the same physiologic change) and the wall thickness method ca n be used in cases when the intima-media thickness cannot be measured, arterial Nail thickness measurement may serve as an alternate or conf irmatory test of peripheral artery atherosclerotic severity.