CT angiography: application to the evaluation of carotid artery stenosis

To determine whether computed tomographic (CT) angiography can be used to accurately quantify carotid stenoses and differentiate severe stenoses from occlusions.

CT angiography was used to evaluate 50 carotid arteries in 27 patients who were referred for surgical evaluation after diagnosis of carotid stenosis and who had undergone standard angiography. Four observers read each study separately in a blinded fashion, then all four observers together reviewed those studies in which the individual readings differed to reach a consensus reading.

The consensus readings for the two modalities were in agreement on stenosis category in 41 (82%) of the 50 carotid arteries (kappa W = 0.852 +/- 0.114). The consensus readings in the other nine arteries differed by only one category; seven had less severe stenosis at CT angiography and two had more severe stenosis. The CT angiograms also depicted a variety of additional abnormalities, including loops (n = 6), aneurysms (n = 2), and ulcers (n = 4).

These results indicate that CT angiography can non-invasively provide most of the information needed before carotid endarterectomy.