Urodynamic findings in boys with posterior urethral valves after treatmentwith primary valve ablation or vesicostomy and delayed ablation

Purpose: Primary valve ablation and temporary vesicostomy with delayed valv e ablation are alternative initial management procedures in neonates and in fants with posterior urethral valves. To investigate whether initial vesico stomy followed by delayed valve ablation and simultaneous vesicostomy closu re may lead to more alterations in bladder function than primary valve abla tion only we retrospectively compared postoperative urodynamic findings in 2 small groups of patients. Materials and Methods: From 1980 to 1990, 15 male infants 19 days to 34 mon ths old with posterior urethral valves were treated with 1 of 2 initial sur gical approaches, including valve ablation only in 8 (group 1), and primary vesicostomy and delayed valve ablation associated with concomitant vesicos tomy closure in 7 (group 2). Mean age at valve ablation and vesicostomy in groups 1 and 2 was 10.8 +/- 11.2 months (range 1 to 35) and 55.4 +/- 43.3 d ays (range 19 to 151), respectively. Average duration of vesicostomy divers ion was 33.6 +/- 18.8 months (range 14 to 70). All patients underwent conve ntional urodynamics postoperatively using normal saline at room temperature . In groups 1 and 2 mean age at followup was 11.5 +/- 6.6 (range 5 to 16.2) and 9.4 +/- 3.1 (range 4.10 to 14) years, respectively. Controls comprised 46 age matched males who underwent urodynamics using similar methodology. Results: Postoperative urodynamic assessment of maximum cystometric bladder capacity and the incidence of detrusor instability in each treatment group were not statistically different. In group 1 bladder capacity was signific antly higher than that in controls (p <0.0001). In group 2 mean end filling detrusor pressure was increased compared with that in group 1 (29 cm. wate r, range 15 to 60 versus 8, range 4 to 21). Compliance was significantly lo wer in group 2 than in group 1 (p <0.0005). Analysis of detrusor voiding pr essure at maximum flow was not significantly different in the 2 groups, We noted detrusor under activity in 1 group 1 and 2 group 2 cases: In these pa tients post-void residual urine volume was 8% to 66% of cystometric bladder capacity. However, only 1 of these 3 patients who required augmentation cy stoplasty needed intermittent catheterization. Urodynamic patterns of outfl ow obstruction developed in 1 patient in each group, including urethral str icture and bladder neck obstruction. At followup we observed no difference in renal function impairment in the 2 groups. Conclusions: Our retrospective study of rapid filling cystometry suggests t hat primary valve ablation for posterior urethral valves is associated with a better bladder function outcome than that in patients treated with vesic ostomy and delayed valve ablation. Therefore, although cutaneous vesicostom y may be performed as initial management of posterior urethral valves, prim ary valve ablation is the most effective surgical option in these cases.