Stenosis of the internal carotid artery at the bifurcation. Radiologic definition and Doppler diagnosis

: One hundred internal carotid arteries with varying degrees of stenosis were studied by angiography and doppler ultrasound. We found the minimal diameter of a stenosis, measured in mm, more suitable as reference for the doppler-based method than verbal assessment of a stenosis as slight, moderate or pronounced. The sensitivity and specificity of maximal blood velocity to diagnose high-grade stenosis is satisfactory for screening patients who might benefit from endarterectomy. Spectral velocity spread, or comparison of the velocity in the stenosis with that of a cranial reference segment of the artery did not increase the sensitivity to detect low-grade stenoses.