[Clinical and neuro-urodynamic assessment of radical prostatectomy]

To study the clinical and urodynamic parameters after radical prostatectomy in order to standardize the management of these patients in the medium-term.

35 cases submitted to radical prostatectomy from February, 1989 to March, 1994 were retrospectively evaluated clinically and urodynamically using a clinical questionnaire, free flowmetry, cystometry, pressure/flow voiding test with simultaneous videocystography and sacral-evoked potentials. The mean age was 65 years and mean follow-up was 14 months.

80% (28) were continent or minimally incontinent on exertion, 9% (3) required the use of some absorbent system and 11% (4) were completely incontinent and required the use of a collecting system. No statistical differences were observed between continence status and tumor stage, patient age or neurovascular preservation. Overall the urodynamic parameters fell within the normal ranges, except for a reduced maximum cystometric capacity. A significant difference (p = 0.05) was found in those patients with significant incontinence vs those who did not for maximum free flow, which disappeared on flowmetry with transducer catheter. Seventy per cent of the incontinent cases were evident on evaluation; 60% had stress incontinence and 40% had instability waves with differential pressure over 80 cm H2O. Six per cent met the criteria for obstruction, whose localization was done during videocystography. Eleven per cent showed non inhibited contractions and 6% showed diminished bladder compliance. The sacral reflex arch was normal in all patients.

The urodynamic study was found to be normal in the majority of patients submitted to radical prostatectomy; therefore performing the study routinely is not justified. However, incontinent patients and those with disturbances on free flowmetry may show incontinence due to instability or obstruction of the urethrovesical junction. We therefore advocate performing a complete study on all patients with significant incontinence and free flowmetry for the rest at least three months after surgery and a complete study should be done if disturbances are found.