Radionuclide assessment of bladder-emptyingfunction in normal male population and in patients before and after prostatectomy

Abstract

Radionuclide assessment of the bladder-emptying function was evaluated in 82 normal individuals and in 16 patients before and after prostatectomy. The parameters evaluated were: average flow rate (AFR), peak flow rate (PFR), corrected peak flow rate (CPFR = PFR/[bladder volume] 0.5), ejection fraction (EF) of the bladder, and post-voiding residual urine (RU) volume. A good interobserver reproducibility was found in 19 measurements. Urinary flow rates, EF, and RU showed a highly significant statistical difference between normal individuals and patients before surgery: AFR, 9.2 +/- 5.1 vs. 2.9 +/- 1.5 mL/sec; PFR, 19.5 +/- 9.2 vs 7.4 +/- 3.2 mL/sec; CPFR, 1.17 +/- 0.34 vs 0.54 +/- 0.22; EF, 95.6 +/- 4.6 vs 68.2 +/- 23.2 percent; and RU, 11.8 +/- 15.8 vs 93.4 +/- 115 mL; respectively. After prostatectomy the urinary flow rates showed a highly significant improvement and did not differ from the normal individuals: AFR, 7.9 +/- 2.7 mL/sec; PFR, 19.0 +/- 6.4 mL/sec; and CPFR, 1.32 +/- 0.57. The EF after surgery (91.7 +/- 10.9%) was lower than in normal individuals, but showed a significant improvement compared with EF before surgery. The RU after surgery (27.4 +/- 48.0 mL) although lower than before surgery did not differ significantly and was greater than in the normal individuals. No relationship between age and flow was found in this study. Both average and peak flow rates were related to the bladder volume. This method involves a single, noninvasive procedure which enables determination of bladder-emptying function.