Can the posterior:anterior urethral ratio on voiding cystourethrogram be used as a reliable predictor of successful posterior urethral valve ablation in male children?

Abstract

Background The role of the voiding cystourethrogram (VCUG) in the follow-up of children with posterior urethral valves (PUVs) post-ablation has been considered a standard practice. The urethral ratio and gradient of change have proven to be useful. Objectives We aimed to review the role of the ‘ideal’ ratio on predicting residual PUV post-ablation. Methods A systematic review of the PubMed, SCOPUS and Web of Science databases was performed (April 2019). The search terms included ‘Urethral Ratio and Posterior urethral valve ablation’. All cited reference lists were further evaluated for additional inclusive studies. Results Eleven studies were identified, of which nine were relevant to the topic. Case reports, comments and adult and animal studies were excluded, leaving four studies for critical review. In total, 338 patients were assessed. The control group consisted of 167 age-matched, male children. Study regions included India and Australia. The ages ranged from 15 days to 3.4 years. Ablation methods included the use of a resectoscope with cutting diathermy, cold knife or Bugbee electrode. The mean urethral ratios in the control group ranged from 1.04 to 1.73. The suggested predictive urethral cut-off ratios recommended include 2.2 ( p = 0.001), 2.5–3 and 3.5. Conclusion Although the precise cut-off ratio could not be clearly defined in this review, a urethral ratio less than a range of 2.2–3.5 has proven to be a beneficial predictor of ablation success and should thus be incorporated into standard VCUG reporting templates in the follow-up of PUVs in male children in resource-limited settings.

Posterior Urethral Valve Type II: Case Report

“…The endoscopic approach allows identification and resection of the valves under direct vision, associated with bladder neck incision, by the resectoscope with electrode knife, hook, cold blade, or inflated balloon catheter. [7,8,9,10,11] The bladder neck incision in conjunction with valve resection has again been suggested to improve bladder dynamics. [12,13,14] In our case we use the cold blade handset with bladder neck incision to relieve the pressure.…”