The Adaptation of Urethral Pressure Profiles to Detect Sphincter Incompetence and Sphincter Obstruction using a Microcomputer

Abstract

A new system for performing urethral pressure profiles, the fluid bridge test and micturitional urethral pressure profiles has been designed based on the use of a microcomputer. The method described has not only led to major improvement in the presentation and accuracy of these tests but for the first time urethral profilometry has been adapted to detect sphincter incompetence and obstruction in 1 simple method. The fluid bridge test was performed on 46 men and 18 women. The results suggested that this test was excellent for urodynamic evaluation of retrograde ejaculation, post-prostatectomy incontinence and vesicourethral neuropathy, and its value was confirmed in women with stress incontinence. Micturitional urethral pressure profiles were performed in 38 men and 2 women. Not only was this test found to correlate well with conventional methods of detecting obstruction but it was able to diagnose urinary outflow obstruction in patients with equivocal pressure/flow studies and patients with acontractile detrusors. It also allowed diagnosis of the site of obstruction in men with vesicourethral neuropathy without the need for radiological screening.

Comparison of Pressure/Flow Studies with Micturitional Urethral Pressure Profiles in the Diagnosis of Urinary Outflow Obstruction

“…One of the main criticismsof the urethral pressure profile has been its inability to determine whether the urethral sphincter mechanisms are competent, incompetent or obstructive (Abrams, 1979). The adaptation of this investigation using computer technology to include the fluid bridge test (Desmond et al, 1985) and the micturitional urethral pressure profile (Desmond and Ramayya, 1987) has restored the credibility of fluid-perfused urethral profilometry and now offers a realistic alternative approach to assessing lower urinary tract dysfunction.…”

Quantification of Bladder Outlet Obstruction by Measurement of Urethral Opening Pressure Using an Adapted Fluid Bridge Test

“…The process of micturition occurs by contraction of the detrusor and simultaneous relaxation of the distal sphincter mechanism. In the unobstructed male the bladder neck opens widely, there is no recordable pressure drop across the bladder neck, (Yalla et al, 1980;Desmond and Ramayya, 1987) and the flow controlling zone is in the region of the distal sphincter (Griffiths, 1980). In patients with bladder neck obstruction the bladder neck fails to open fully and there is a recordable pressure drop across the bladder neck during voiding (Desmond and Ramayya, 1988).…”