LASER-DOPPLER FLUX IN NORMAL AND ARTERIOSCLEROTIC CAROTID-ARTERY WALL

The perfusion of the arterial wall was evaluated in vivo in normal sec tions of the carotid artery, in sections with fibrotic plaques and in sections with plaques and diffuse calcifications using laser Doppler f lowmetry. Patients with carotid plaques undergoing carotid endarterect omy were studied. Using intra-operative ultrasound three different lev els of atherosclerosis involvement of the arterial wall were defined: normal arterial wall where all components (intima, media and adventiti a) were clearly separated and intact; wall with intima-media thickenin g and fibrotic plaques (without calcifications); sections with diffuse ly calcified plaques. In 20 patients 20 normal sections, 20 sections w ith fibrotic plaques and 20 sections with large plaques and diffuse ca lcifications were studied. Diabetic and hypertensive patients were exc luded. Wall flux was measured on the external surface of the common ca rotid artery before complete dissection for endarterectomy. Measuremen ts were recorded when at least 3/4 of the adventitia was intact for a length of at leaf 4 cm. The average flux in normal sections was higher (p < 0.05) than in sections with fibrotic plaques and in sections wit h calcified plaques. A significant difference in flux (p < 0.05) betwe en fibrotic (decreased flux) and calcified areas (very low flux) was r ecorded. In conclusion a higher wall perfusion was observed in normal arterial sections in comparison with sections with plaques. Sections w ith diffuse calcifications and larger plaques had a very low flux.