Additional layer for better outcome in tubularized incised plate of hypospadias repair: Systematic review and network meta-analysis of randomized control trials.

Abstract

<h4>Introduction</h4>Hypospadias is a prevalent congenital defect of the male urethra, usually repaired using the tubularized incised plate (TIP) procedure. However, post-operative complications remain a challenge. Performing additional interventions have been proposed to reduce the risk of complications after TIP. Nonetheless, a comprehensive comparison of such interventions is limited.<h4>Methods</h4>Systematic review and network meta-analysis (NMA) were conducted on randomized controlled trials (RCTs) that reported the efficacy of additional layers or flaps in TIP. We performed Bayesian statistics incorporating random-effects modelling. The interventions were ranked based on the surface under the cumulative ranking curve (SUCRA).<h4>Results</h4>This NMA of 22 RCTs involved a total of 1,994 pediatric patients. Multiple interventions may potentially reduce the rate of urethrocutaneous fistula (UCF), including the double dartos flap (DDF) (SUCRA 82.61%, [risk ratio (RR): 0.104, 95% confidence interval (CI): 0.0189-0.321], absolute risk reduction (ARR): 13.74%), the tunica vaginalis flap (TVF) (SUCRA 60.19%, [RR: 0.295, 95% CI: 0.0766-0.784], ARR: 17.32%), and a combination of the tunica vaginalis with dartos fascia (TVF + SDF) (SUCRA 98.83%, [RR: 1.04 × 10^-9, 95% CI: 2.02 × 10^-28 - 0.102], ARR: 12%). No intervention significantly improved the secondary outcomes. Sensitivity analysis showed the robustness of the results. The model fitness and inconsistency test indicate that the findings were strong and consistent.<h4>Conclusions</h4>This NMA found that none of the interventions were definitively superior, especially for the secondary outcomes. However, DDF was found to be most successful in reducing the rate of UCF after TIP hypospadias repair. There is a need for further research, specifically in the realm of TVF, TVF + SDF, and autologous platelet derivatives. Also, head to head comparisons between interventions are strongly recommended.