Accuracy of In Vivo Carotid B-Mode Ultrasound Compared With Pathological Analysis

<jats:p> <jats:italic>Background and Purpose</jats:italic> —This study aimed to determine the correlation of in vivo ultrasound measurements of intima-media thickening (IMT), lumen diameter, and cross-sectional area of the common carotid artery (CCA) with corresponding measurements obtained by gross pathology and histology. </jats:p> <jats:p> <jats:italic>Methods</jats:italic> —Sixty-six moribund neurological patients (mean age 71 years) underwent B-mode ultrasound of the CCA a few days before death. During autopsy, carotid specimens were removed in toto. Carotid arteries were ligated and cannulated for injection of a hydrophilic embedding material under standardized conditions. The carotid bifurcation was frozen and cut manually in 3-mm cross slices. Digital image analysis was carried out to determine the diameter and the cross-sectional area of the frozen slices of the CCA. IMT was assessed by light microscope. Ultrasonic and planimetric data were compared. </jats:p> <jats:p> <jats:italic>Results</jats:italic> —Mean measurements of lumen diameter and cross-sectional area were 7.13±1.27 mm and 0.496±0.167 cm <jats:sup>2</jats:sup> , respectively, by ultrasound, and 7.81±1.45 mm and 0.516±0.194 cm <jats:sup>2</jats:sup> , respectively, by planimetric analysis of the unfixed redistended carotid arteries ( <jats:italic>R</jats:italic> <jats:sup>2</jats:sup> =0.389 and 0.497). The mean IMT was 1.005±0.267 mm by ultrasound and 0.67±0.141 mm histologically, resulting in a mean difference of −31%. </jats:p> <jats:p> <jats:italic>Conclusions</jats:italic> —Transcutaneous B-mode ultrasound provides a reliable approach for in vivo measurements of the cross-sectional area and, less exactly, of the lumen diameter of the CCA. Compared with histological results, in vivo ultrasound measurements of the IMT are systematically larger. </jats:p>