The Role of Carotid Duplex Ultrasound in Evaluating Plaque Morphology: Potential Use in Selecting Patients for Carotid Stenting

Purpose: To study the role of duplex ultrasonography in evaluating plaque morphology and its correlation to neurological symptoms and cerebral infarctions on computed tomographic scans. Methods: The hospital records of 181 patients (107 males; average age 66 years, range 41 to 89) with > 50% carotid stenosis (29 bilateral lesions) who had undergone duplex ultrasonography, carotid arteriography, and cerebral computed tomography were studied retrospectively. Of 210 duplex examinations, 139 were appropriate for morphological analysis of surface characteristics and echogenicity. Results: Over half of the plaques examined had irregular surfaces (81, 58%) and displayed mixed (i.e., heterogeneous) echogenic patterns (74, 53%). Irregular (68 of 81, 84%) and heterogeneous (65 of 74, 88%) plaques were associated with ipsilateral neurological symptoms (p < 0.0001). Similarly, 44 (54%) of 81 irregular plaques and 42 (57%) of 74 heterogeneous plaques were found in patients with cerebral infarctions in the carotid territory (p < 0.0001). Conclusions: Heterogeneous and/or irregular plaques were more often associated with both neurological symptoms and infarctions than smooth or homogeneous plaques. These findings may have implications in patient selection for endoluminal therapy.