Accuracy of Color/Duplex
Carotid Sonography
· near 90%     Polak et al:
         Radiology 173:793, 1989
         Neale et al:
         J Vasc Surg 20:642, 1994
· 65-71%     NASCET Study
         Eleiasziw et al:
         Stroke 26:1747, 1995
Crittenden: Radiology 205:577, 1997 (Letter to the Editor)