Uroflowmetry parameters before and after meatoplasty for primary symptomatic meatal stenosis in children.

Abstract

One measure of a successful outcome of meatoplasty for symptomatic urethral meatal stenosis has traditionally been witnessed voiding and subjective assessment of urinary stream. This evaluation is flawed by nonobjective criteria and potential differing interpretations by different clinicians. We sought to assess urinary flow better following meatoplasty using voiding uroflowmetry to measure objectively response to treatment. We retrospectively reviewed the records of 22 boys who underwent meatoplasty for symptomatic meatal stenosis and who had uroflowmetry (flow rates, voided volumes and voiding times) performed preoperatively and postoperatively. Statistical comparison of voiding parameters was analyzed using Student's paired t test. Mean patient age was 7 years (range 4 to 13). There were no complications and no recurrences associated with meatoplasty during a mean followup of 12 months. There was a significant increase in maximum urinary flow rates following meatoplasty (9.7 ml per second preoperatively vs 16.4 ml per second postoperatively, p = 0.001). Mean postoperative post-void residual volumes and voiding times were significantly lower than preoperative values, at 13.9 ml vs 19.3 ml (p = 0.01) and 29 seconds vs 19 seconds (p = 0.03), respectively. Voided volumes did not differ between the time intervals (157 ml preoperatively vs 147 ml postoperatively, p = 0.25). Flow patterns were abnormal in 19 of 22 patients preoperatively, and 88% of these patients had bell curve-shaped patterns following meatoplasty. Flow rates measured by noninvasive uroflowmetry showed significant increases following meatoplasty for meatal stenosis. Uroflowmetry represents an objective method to assess outcomes following meatoplasty compared to subjective visualization of the urinary stream during voiding.