Megacystis and incomplete bladder emptying in the absence of fixed urethral obstruction is identified in up to 50% of males with prune belly syndrome (PBS). Urodynamics show decreased detrusor contractility and relative outflow resistance that in combination prevents effective bladder emptying. The voiding dysfunction can be progressive and while urinary diversion with a cutaneous vesicostomy is commonly utilized in infants in diapers this is not a good option in a toilet trained child. Clean intermittent catheterization is a preferred management but can be difficult in boys with normal penile sensation. We report our experience with external sphincterotomy to reduce outflow resistance in toilet trained males with PBS.
Methods
We retrospectively reviewed our patient database for patients with PBS ICD-9 code (756.71) and a history of external sphincterotomy CPT code (52276). Sphincterotomy was performed using a pediatric resectoscope and a single incision at the twelve o’clock position using a pure cutting current. An indwelling catheter was left for 24-48 hours after the procedure. Patients were followed at 6 month intervals. Patient demographics, indications for sphincterotomy and clinical outcomes were tabulated. Post-void residual volumes were determined by either catheterization or US.
Results
Six sphincterotomies were performed in five toilet trained males with PBS between 1995 and 2010. All patients had progressive hydronephrosis on US. In four cases intermittent retention or urinary tract infections were additional indications to improve bladder emptying. In all cases parents/children were unable/refused to perform CIC. Hydronephrosis returned to baseline in all patients after sphincterotomy. No patient had recurrent urinary retention. None of the patients developed incontinence after sphincterotomy. All but the oldest patient is currently active in our clinic.
| age (yrs) | 10 indication | Pre-procedure PVR (ml) | Post-procedure PVR (ml) | Pre/post peak flow rate (ml/sec) | Follow-up | |
| 1 | 17 | Progressive hydronephrosis | 2500 | 500 | not available | recurrence @ 3 years now on CIC |
| 2 | 3 | UTI's | 350 | 50 | two/nine | stable @ 12 yrs |
| 3 | 3 | Intermittent retention | 360 | 100 | not available | no recurrence @ 5 years |
| 4a | 9 | Intermittent retention | 2200 | 500 | six/nine | progressive hydro @ 3 yrs |
| 4b | 12 | Progressive hydronephrosis | 1400 | 250 | three/ten | well @ 12 months |
| 5 | 5 | UTI's | 2000 | 30 | two/ten | well @ 6 months |
Conclusion
External sphincterotomy can effectively treat incomplete bladder emptying in select patients with PBS. It decreases renal dilation and urinary tract infections while protecting renal function and can eliminate the need for CIC.