Bladder function associated with posterior urethral valves after primary valve ablation or proximal urinary diversion in children and adolescents.

Purpose: We retrospectively reviewed 2 series of patients with posterior urethral valves treated initially with valve ablation preceded by bilateral cutaneous ureterostomies or valve ablation alone to evaluate and compare bladder function behavior of each treatment group.

Materials And Methods: From 1970 to 1983, 19 males 22 days to 21 months old with posterior urethral valves were treated with 1 of 2 initial surgical approaches, including upper tract diversion, delayed undiversion and ablation in 11 (group 1), and primary valve ablation only in 8 (group 2). Median patient age at the time of cutaneous urinary diversion and primary valve ablation for groups 1 and 2 was 7 and 9 months, respectively. Median duration of bladder defunctionalization was 48 months. All patients were evaluated urodynamically after initial ablation or re-functionalization of the bladder using standard rapid fill cystometry. Median patient age for groups 1 and 2 was 14 and 9.5 years, respectively, at the time of urodynamic testing 16 and 12.6 years, respectively, at followup.

Results: Urodynamic assessment revealed detrusor instability in 5 group 1 patients but in only group 2 1 patient. Group 2 patients had significantly lower median end filling pressure (4 versus 15 cm. water, p <0.03) and higher maximum bladder capacity (1.4 versus 0.8, p <0.005) than those in group 1. Group 1 patients had lower compliance than those in group 2 (median 15 versus 82 cm. water, p <0.05). Further analysis showed no difference between groups 1 and 2 in overall median voiding detrusor pressure at maximum flow (51 versus 52.6 cm. water, respectively). Cystometric detrusor under activity patterns were noted in 5 group 1 and 2 group 2 patients. Residual urine volumes were 17%, 31%, 19% and 8% of bladder capacity, respectively, in 2 group 1 and 2 group 2 patients. At final followup 5 group 1 and 2 group 2 patients had renal function deterioration. Two other group 1 patients and group 2 had progression to end stage renal failure. A higher ureteral reimplantation rate was noted in group 1 (63%) than group 2 (6%).

Conclusions: This retrospective study revealed that long-term bladder function of patients with posterior urethral valves treated with temporary supravesical diversion is affected more adversely than those treated with valve ablation alone.