Changes of urodynamic findings after radical retropubic prostatectomy

We wanted to evaluate the urodynamic changes of radical retropubic prostatectomy in patients with localized prostate cancer and identify specific factors that could influence the postoperative continence status.

Sixty-six consecutive patients (mean age 68 years) were studied urodynamically within 1 week before surgery, and 44 of them at a mean 7.6 months after radical intervention.

Complete urinary continence was achieved in 37/44 men (84. 1%) after 6 months and in 43/44 patients (97.7%) 1 year after surgery. Stress incontinence of varying degree improved with time. Seven patients demonstrated a moderate incontinence 4 months after radical prostatectomy and 1/7 was still incontinent after 1 year. Mean flow rate, maximum detrusor pressure, maximum urethral closure pressure (at rest and voluntary contraction of the sphincter) and functional urethral length showed significant changes after surgery. Detrusor instability, which was present in 31.8% of the 66 patients preoperatively, was not responsible for any case of postoperative incontinence. The urethral pressure profile was significantly reduced in all patients after surgery.

The present study indicates that there are no preoperative alterations in bladder function such as detrusor instability to identify patients at risk for postoperative incontinence. Postoperative incontinence seems to depend upon sphincteric deficiency as expressed by the reduced pressures in the sphincteric mechanism.