Comparison of the ECST, CC, and NASCET grading methods and ultrasound for assessing carotid stenosis

We compared three angiographic methods for grading of carotid stenosis and examined the correlation between angiographic and ultrasound findings. Two observers independently measured 111 carotid stenoses on arteriographic fil ms of 84 patients. The stenoses were graded according to the European Carot id Surgery Trial (ECST), North American Symptomatic Carotid Endarterectomy Trial (NASCET), and Common Carotid (CC) methods. The results obtained by th ese methods were compared, and the interobserver reproducibility of the mea surements was calculated. In addition, all angiographic results were compar ed to ultrasound findings obtained before angiography. Measurements using t he CC method were the most reproducible and those using the NASCET method t he least. The NASCET method underestimated the degree of stenosis compared to the other meth ods. The ECST and CC methods yielded almost identical res ults (97% agreement). Ultrasound provided an accuracy of 94% compared to EC ST and CC methods and 84% compared to the NASCET method. Interobserver repr oducibility of angiographic quantification of carotid stenoses was best for the CC and ECST methods and least for the NASCET method. Ultrasound demons trated better accuracy than the ECST and CC methods.