Statement of the Problem: Annually, in the US, almost 750,000 individuals suffer a stroke and approximately 200,000 of them die within the year. The yearly number of strokes is expected to increase by 50% by 2030 because of a rapid increase in the elderly population. Death and chronic disability arising from stroke is costly. In 2003, the total cost for stroke services was estimated to be $51 billion. Studies have shown that neurologically asymptomatic individuals with significant atherosclerotic narrowing (>50% stenosis) of the internal carotid artery’s (ICA) luminal diameter are at heightened risk of stroke. However, identification of these individuals and timely medical and/or surgical interventions can often preclude a stroke. Carotid Doppler ultrasonography (CDUS) is currently the primary modality for identifying ICA atheromas, determining extent of stenosis and thereby categorizing stroke risk. Panoramic radiographs obtained during routine oral and maxillofacial surgery may also image atheromas if they contain adequate amounts of calcium. However, a large scale study employing contemporaneous CDUS criteria to characterize the severity of disease identified by these radiographs has not been performed. Materials and Methods: We examined the radiographs of 1,400 consecutively treated, neurologically asymptomatic oral surgery patients, over age 50. Individuals having an atheroma received a CDUS evaluation employing criteria developed in 2003 by Consensus Panel of the Society of Radiologists in Ultrasound. Method of Data Analysis: The ICA was considered normal when the ICA peak systolic velocity (PSV) was <125 cm/sec and no plaque or intimal thickening was visible sonographically on the gray scale image. A <50% ICA stenosis was diagnosed when the ICA PSV was <125 cm/sec and visual plaque estimation on the gray scale image was <50% stenosis. A 50–69% ICA stenosis was diagnosed when the ICA PSV was 125–230 cm/sec and >70% ICA stenosis was diagnosed when the ICA PSV was greater than 230 cm/sec. Results: Fifty-three patients or 3.8% of the sample population had radiographically identified atheromas. CDUS evaluation of the 86 ICAs with a radiographically identified atheroma revealed that 73 (84.8%) had <50% stenosis, 9 (10.5%) had 50–69% stenosis, and 4 (4.7%) had 70–95% stenosis. The 20 ICAs without radiographic evidence of an atheroma each exhibited <50% stenosis on CDUS. Conclusion: These results suggest that slightly more than 15% of ICAs with a radiographically identified atheroma have hemodynamically significant (>50%) stenosis which places the patient at heightened risk of future stroke. References Friedlander AH, Friedlander IK, Yueh R, et al: The prevalence of carotid atheromas seen on the panoramic radiographs of patients with obstructive sleep apnea and their relation to risk factors for atherosclerosis. J Oral Maxillofac Surg 57:516, 1999 Grant EG, Benson CB, Moneta GL, et al: Carotid artery stenosis: Gray-scale and Doppler US diagnosis. Society of Radiologists in Ultrasound Consensus Conference. Radiology 229:340, 2003 Funding Source: Department of Veterans Affairs.