Urethral pressure reflectometry, a novel technique for simultaneous recording of pressure and cross-sectional area in the prostatic urethra: testing in men without bothersome lower urinary tract symptoms.

Objective. Urethral pressure reflectometry (UPR) was introduced in 2005, for simultaneous measurement of pressure and cross-sectional area in the female urethra. It has shown to be more reproducible than conventional pressure measurement. Recently, it has been tested in the anal canal and the prostatic urethra. The primary aim of this study was to describe UPR in men without bothersome lower urinary tract symptoms. Material and methods. The study investigated 18 men, median age 59 (range 50-77) with UPR and pressure-flow analyses (PQ), the International Prostate Symptom Score and the Danish version of Prostate Symptom Score, flow rate, residual urine measurements, transrectal ultrasound, urethral pressure profilometry and visual analogue scale (Discomfort). UPR parameters measured were opening and closing pressure, opening and closing elastance and hysteresis, from the bladder neck to the sphincter region. Results. All UPR parameters increased significantly from the bladder neck to the sphincter region, except for the opening pressure between the prostate and the sphincter region. Seven men were obstructed according to PQ, but with no significant differences in any other standard urodynamic parameters. The hysteresis in the sphincter region was significantly lower in the obstructed group (p=0.005). Discomfort was significantly lower with PQ compared to UPR (p=0.04). Nine men had slight bleeding from the urethra during measurement with UPR. Conclusions. The increase in all parameters from the bladder neck to the sphincter region is consistent with previous studies measuring the same parameters. The hysteresis may explain why seven men were obstructed according to PQ.