Urodynamics in benign prostatic hypertrophy.

Synchronous urinary flow and pressure studies were carried out on 51 male subjects of whom 12 were normal subjects and 39 had benign prostatic hypertrophy with varying degrees of bladder outlet obstruction. A urodynamic scoring system was evolved for accurate and objective diagnosis of bladder outlet obstruction. The minimum urethral resistance was found to be the most valuable single urodynamic parameter for the diagnosis of bladder outlet obstruction. Hitherto this urodynamic parameter was determined through tedious calculations. In the course of the present study a new instrument, the Urethroresistance, was devised for the direct recording of urethral resistance during micturition.