B-mode ultrasonic guidance was used to perform 41 percutaneous renal biopsies in 40 patients. Puncture point of the kidney was determined at 3cm. above the lower pole, 1cm. inside from the lateral border of the kidney. Needle was punctured at an angle of 45 degrees for the skin surface. Renal tissue was obtained in 40 of the 41 procedures (97.6%), and 37 specimens contained 5 or more of glomeruli which were adequate for histological diagnosis. Gross hematuria was observed in 3 patients (7.3%) as the complication, and these were subsided within 1 to 4 days. Other complications did not occur. The depth of renal puncture site from the skin was 4.02cm. on the average and never exceeded 6 cm. in any case. A highly significant correlation was observed between the depth of the renal capsule from the skin and the distance of the skin puncture site from the median line (r=0.766, p<0.001). Determination of renal localization by ultrasonography has proved to be a safe and highly successful means of guidance for the performance of percutaneous renal biopsy, and it has many advantages over other techniques.
