Penile urethral compression-release maneuver as a non-invasive screening test for diagnosing prostatic obstruction

The purpose of this study was to evaluate the feasibility of using a penile urethral compression and quick release maneuver during urination as a potential non-invasive clinical screening tool in the evaluation of patients with voiding dysfunction and the diagnosis of prostatic obstruction. The penile compression-release maneuver was performed in adult men with symptomatic voiding dysfunction and in asymptomatic normal men by compressing the penile urethra for 2-3 seconds after the initiation of flow and quickly releasing the compression. The penile compression-release index, calculated from the resulting flow rate surge (Q(surge)) and the steady flow rate (Q(surg)-Q(s)/Q(s)), was analyzed with respect to the type of voiding dysfunction. A comprehensive urodynamic study was performed in each patient to determine the presence and severity of prostatic obstruction and to measure detrusor contractility. The penile compression-release indices measured with this maneuver in patients with bladder outlet obstruction (183+/-76%, n = 43) or detrusor instability (157+/-65%, n = 13) were significantly greater than the index observed in non-obstructed patients with normal contractility (67+/-37%, n = 24) or in non-obstructed patients with impaired detrusor contractility (70+/- 32%, n = 10). In asymptomatic younger men who had normal free flow rates (>15 mL/s), the penile compression-release index (55+/-29%, n = 20) was significantly less than that observed in patients with outlet obstruction or detrusor instability. These findings suggest that the magnitude of the flow rate change generated after the penile compression-release maneuver depends on the magnitude of the isometric detrusor contraction developed during penile urethral compression and on the conduit status of the outlet. In patients determined to have poor urinary flow rates, this non-invasive maneuver has been able to differentiate prostatic obstruction associated with normal detrusor contractility from other causes of low urinary flow rates. Despite these encouraging trends, further studies in a larger cohort are required to determine its potential clinical utility as a screening tool for diagnosing prostatic obstruction.