SUMMARY One hundred patients with asymptomatic carotid bruit or transient ischemic attack (TIA) underwent continuous-wave Doppier (CWD) and real time ultrasound (RTU) testing of their cervical carotid arteries. After ultrasonic studies, 51 patients also underwent bilateral carotid angiography. There was 95 % agreement between CWD and angiography for the diagnosis of a significant (> 50 %) stenosis. The RTU diagnosis of a normal or occluded vessel was correct in 100% of cases. Seven plaques appreciated on RTU may not have been large enough for detection by angiography. In this small series, ulceration confirmed pathologically was more reliably predicted by RTU than by cerebral angiography.Significant ipsilateral carotid plaques occurred more often in patients with amaurosis fugax than in patients with hemispheric TIAs. Ipsilateral plaque ulceration occurred in 50% of symptomatic carotid bruits, but in only 10% of asymptomatic carotid bruits. Plasma concentrations of total cholesterol were significantly higher in TIA patients with carotid stenosis than in controls. Stroke Vol 17, No 1, 1986 CEREBRAL ANGIOGRAPHY is a reliable technique for diagnosis of cerebrovascular disease, but its usage is limited by its high cost and associated risks. Carotid ultrasound testing is safer and less expensive. We used the combination of continuous-wave Doppier (CWD) and real time ultrasound (RTU) testing to evaluate the carotid bifurcations of 100 patients with asymptomatic carotid bruit (ACB) and transient ischemic attack. Material and MethodsFrom June 1982 to September 1983, 100 consecutive Caucasian patients referred to the Neurosonology laboratory with either ACB or TIA were examined by CWD and RTU. These patients ranged in age from 40 to 84 years (table 1). Of 100 patients, 15 had asymptomatic carotid bruit (ACB), 19 had amaurosis fugax, 28 had vertebrobasilar TIAs and 38 had hemispheric TIAs. Fifty-one also underwent fourvessel cerebral angiography and 19 underwent carotid endarterectomy.All CWD scans were performed on supine patients with the 1050 DOPSCAN* imaging system and a 5 MHz transducer using the techniques described by Spencer et al' and Blackwell et al.2 CWD was interpreted as abnormal whenever there was no flow detectable (obstruction) or there was a doppier frequency shift greater than 6 KHz (> 50% stenosis). RTU studies were performed with an 8 MHz high-resolution Biosonics scannert with patients seated in a dental chair. Longitudinal and transverse images of the carotid bifurcation were obtained and videotaped from anteroposterior, lateral and posterolateral projections.• RTU was interpreted as showing obstruction whenever there was no discernible lumen and no appreciable pulsation. Ulcerated plaque was diagnosed by RTU whenever the atheroma had an undercut, crater-like, or markedly irregular surface.The findings of CWD and RTU were compared with the results of cerebral angiography in the 51 patients who underwent angiography. For the correlation of ultrasound results with clinical data, CWD and RTU results ...