Laser Doppler flux in normal and arteriosclerotic carotid artery wall

The perfusion of the arterial wall was evaluated in vivo in normal sections of the carotid artery, in sections with fibrotic plaques and in sections with plaques and diffuse calcifications using laser Doppler flowmetry. Patients with carotid plaques undergoing carotid endarterectomy were studied. Using intra-operative ultrasound three different levels of atherosclerosis involvement of the arterial wall were defined: normal arterial wall where all components (intima, media and adventitia) were clearly separated and intact; wall with intima-media thickening and fibrotic plaques (without calcifications); sections with diffusely calcified plaques. In 20 patients 20 normal sections, 20 sections with fibrotic plaques and 20 sections with large plaques and diffuse calcifications were studied. Diabetic and hypertensive patients were excluded. Wall flux was measured on the external surface of the common carotid artery before complete dissection for endarterectomy. Measurements were recorded when at least 3/4 of the adventitia was intact for a length of at least 4 cm. The average flux in normal sections was higher (p < 0.05) than in sections with fibrotic plaques and in sections with calcified plaques. A significant difference in flux (p < 0.05) between fibrotic (decreased flux) and calcified areas (very low flux) was recorded. In conclusion a higher wall perfusion was observed in normal arterial sections in comparison with sections with plaques. Sections with diffuse calcifications and larger plaques had a very low flux.