URODYNAMIC FINDINGS IN POSTPROSTATECTOMY INCONTINENCE

Due to the large variability in the reported contribution of bladder d ysfunction to postprostatectomy incontinence and the impact this dysfu nction may have on the outcome of selected treatment, we retrospective ly reviewed the videourodynamic findings of bladder and sphincteric fu nction in patients with postprostatectomy incontinence. The contributi ons of bladder and sphincteric causes of incontinence are determined. Ninety-two patients had multichannel videourdynamic testing performed as part of a comprehensive evaluation for incontinence at least 1 year after prostatectomy. Using a 6-French double-lumen catheter in the bl adder and a 10-French catheter in the rectum, all pressures were recor ded continuously while in the upright position. Valsalva leak point pr essures (VLPP) were measured in the absence of a bladder contraction a t a 150-ml volume and at 50-ml increments thereafter until maximum fun ctional capacity was reached. Bladder compliance and bladder capacity were determined and the presence of detrusor instability (DI) was docu mented. Sixty-five patients (71%) presented after radical prostatectom y (RP) and 27 patients (29%) after transurethral resection of the pros tate (TURP). The predominant urodynamic finding was sphincteric incomp etence as VLPP were obtained in 85 patients (92%) and ranged from 12 t o 120 cm water. DI was a common finding, occurring in 34 patients (37% ), and classified as follows: a) phasic instability in 22/34, b) tonic instability in 3/34, and c) mixed phasic and tonic instability in 9/3 4. However, we found DI to be the sole cause of incontinence in only 3 /92 patients (3.3%). There was no statistically significant difference in the incidence of sphincteric incompetence after RP or TURF; howeve r, TURF patients had a higher incidence of DI, which was statistically significant (P = 0.019). There was no correlation of incontinence sev erity and VLPP when comparing preoperative pad usage to VLPP less than or equal to 70 or greater than or equal to 71 cm water. Although blad der dysfunction may be contributing problem in patients with postprost atectomy incontinence, it is rarely the only mechanism for this disord er. VLPP does not correlate with incontinence severity. Although sphin cteric incompetence is the most common mechanism contributing to incon tinence after prostatectomy, bladder dysfunction may coexist or be an isolated cause of postprostatectomy incontinence. Therefore, urodynami c studies are important to illustrate the exact cause(s) of incontinen ce in each individual patient after prostatectomy. (C) 1998 Wiley-Liss , Inc.