[The evaluation of simple estimation method of prostate size by transabdominal ultrasound]

We evaluated 107 patients who were diagnosed as benign prostatic hypertrophy preoperatively and underwent transurethral resection of the prostate. We obtained the maximum cross section of the adenoma by transabdominal scanning using a real-time large-sized convex scanner and a 3.5 MNz. transducer. Regarding the adenoma as an ellipsoid with revolution around its transverse axis, 2 diameters (breadth and height) were measured with transverse scan (a and b, respectively). We then calculated the values of the estimated size of the adenoma according to the formula for a spheroid. V = (pi/6) ab2. Thus the calculated weight were correlated with the resected weight of the specimen after a complete transurethral resection of the prostate. As a result, the sonographic estimation provided a high correlation coefficient: r = 0.956. The result suggested that our method of transabdominal ultrasonography in the preoperative evaluation of the prostatic size was rapid, simple and noninvasive, was well adapted for screening sufferers from prostatic diseases, and gave preoperative information for transurethral resection of the prostate and other surgical operation.