Pointwise assessment of three-dimensional computer reconstruction of mitral leaflet surfaces from rotationally scanned echocardiograms in vitro

Three-dimensional transesophageal echocardiography offers promise for improved understanding of mitral leaflet pathology, but it has not been validated quantitatively, nor has the minimum number of imaging planes for satisfactory reconstruction been determined with a rotational scanning geometry. This study assessed its accuracy in vitro by comparing, on a 1 x 1-mm grid, the surfaces of mitral leaflets derived from 5-degree rotational ultrasonic scans with those derived from laser scans of casts of the atrial side of the leaflets. Overall, the ultrasonically derived surface had a mean absolute deviation of 0.65 +/- 0.12 min from the laser-derived surface. Using only alternate imaging planes (10-degree increments) made no significant difference in the overall distribution of deviations (P = .56), although the distributions on some individual specimens differed markedly. We conclude that 5-degree rotational scanning in vitro can reconstruct the mitral valve leaflets with sufficient accuracy and detail to render clinically important features.