[Three-dimensional display of the prostate based on transrectal ultrasonogram].

A software for a lap top computer to display prostatic contour three-dimensionally based on transrectal ultrasonograms was developed, and its clinical usefulness was examined. The prostatic contour of a case with prostatic cancer showed a typical irregular surface, and that of a case with prostatic hypertrophy had a smooth spherical shape, while that of a normal case had a flat shape. Each showed its characteristic shape. Estimation of the prostatic weight by assuming that the prostatic contour has ellipsoidal contour is a simple method for prostatic weight measurement, but it has a tendency to underestimate the weights, especially in normal cases. Three-dimensional display of the contour of prostatic cancer, prostatic hypertrophy, and normal prostate revealed that it could be estimated as ellipsoid in prostatic cancer or hypertrophy, while the normal prostatic contour was too flat to be calculated as such. Among 52 patients with benign prostatic hypertrophy who underwent transrectal ultrasonotomography before and during the anti-androgen therapy more than three time, nine cases showed transient reduction of more than 30% in prostatic weight and then reenlargement of more than 30%. In these cases, three-dimensional display of prostatic contour was done. The display was useful to visualize clearly which part reenlarged. Therefore, usefulness of the three-dimensional display of the prostate was verified.