RESUMO
OBJECTIVE: To estimate the possibilities of using three-dimensional ultrasound study (3D USS) in the diagnosis of the sizes and structure of an atherosclerotic plaque (ASP). MATERIAL AND METHODS: The data obtained by examination of 20 heterogeneous ASPs in the carotid artery wall, by applying 3D USS and magnetic resonance imaging (MRI), were compared. Intra- and interoperator reproducibilities were assessed by the Bland-Altman method; the volume of each plague was measured by two (contour and ellipse) methods. The contour method was used to estimate all plagues; the ellipse method was applied to 13 of the 20 plagues, which was due to the shape of ASPs that rarely had an ellipsoid shape. RESULTS: Intra- and interoperator reproducibilities in ASP volume estimation by 3D USS was as follows: with the use of contour and ellipse algorithms, the coefficient of variation was 7.72 and 3.77%, respectively; with these algorithms, the interoperator reproducibility was 8.18 and 6.21%, respectively; the derived values were not greater than those allowed for medical studies (10%). The coefficients of variations for MRI in the estimation of ASP sizes were significantly higher for inter- and intrareproducibilities (68.82 and 43.4%, respectively). CONCLUSIONS: The results of this investigation agree with thedata available in the literature and support that 3D USS is an effective diagnostic me-hod in evaluating the magnitude of an ather-sclerotic process.