Color-flow Doppler-assisted duplex imaging fails to detect ulceration in high-grade internal carotid artery stenosis.

PURPOSE

Pathoanatomic studies suggest that plaque surface disruption, particularly ulceration, plays a key role in the destabilization of internal carotid artery stenosis. Until now, the validity of color-flow Doppler-assisted duplex imaging in detecting such pathoanatomically defined plaque surface abnormalities is unclear.

METHODS

We prospectively determined the interobserver reliability and validity of detecting plaque ulceration by means of preoperative color-flow Doppler-assisted duplex imaging in 43 consecutive patients with high-grade (> or = 70%) internal carotid artery stenosis, comparing these ultrasonographic findings with pathoanatomic evaluations of the corresponding endarterectomy specimens.

RESULTS

Interobserver reliabilities for detecting carotid plaque ulceration were kappa= 0.57 for ultrasonography and kappa = 0.82 for the pathologic reference method. Color-flow Doppler-assisted duplex imaging (observer consensus) failed to detect pathoanatomically defined ulceration (chi square = 0.43; p = 0.51). Likewise, sensitivity, specificity, overall accuracy, and positive predictive value were poor (33%, 67%, 56%, and 46%, respectively).

CONCLUSIONS

We conclude from our data that color-flow Doppler-assisted duplex imaging is not a reliable or valid means to identify plaque ulceration in high-grade carotid artery lesions.