Two- and three-/four dimensional perineal ultrasonography in men with urinary incontinence after radical prostatectomy

Objective: To investigate the feasibility and inter-investigator reproducibility of perineal ultrasonography in men with and without post-prostatectomy urinary incontinence (PPI).

Patients and methods: This clinical pilot study involved 33 male patients, with a mean (range) age of 67.8 (51-76) years, who underwent radical prostatectomy (RP) ≥1 year ago. We investigated 21 men with clinically and urodynamically proven grade ≥2 PPI and compared them with 12 men without PPI in objective testing as well as in validated questionnaires. We used an abdominal 3.5-5 MHz ultrasound probe, which was placed at the perineum between scrotum and anus. With the help of three-/four-dimensional (3D/4D) multislice imaging we obtained good visualization of the bladder neck, the urethra and pelvic floor muscle contraction. The data from all 33 men was evaluated by two investigators and archived images and videos were also analysed by two independent investigators not present at the actual investigation.

Results: Using perineal ultrasonography we were able to visualize hypermobility of the proximal urethra, funnelling of the bladder neck, voluntary pelvic floor contraction, urethral and paraurethral fibrosis, and suture or sling material. Men with and without PPI differed mainly in the degree of hypermobility of the proximal urethra and opening of the bladder neck. Inter-investigator agreement was 100% in assessing paraurethral tissue and voluntary muscle contraction and 94% in quantifying mobility of the proximal urethra. We were able to evaluate the bladder neck opening in 85% of the men. There was 82% agreement between the initial investigators in evaluation of the bladder neck and 76% in quantifying mobility of the proximal urethra using retrospective analysis of stored images.

Conclusions: Two-dimensional and 3D/4D perineal ultrasonography provides more insight into the diagnosis of men with PPI. Perineal ultrasonography can be used further as a visual aid for biofeedback to teach correct muscle contraction of men with stress incontinence after radical prostatectomy.