Comparing the Outcomes of Tubularized Incised Plate Urethroplasty and Dorsal Inlay Graft Urethroplasty in Children with Hypospadias: A Systematic Review and Meta-Analysis

Background: Due to their simplicity and excellent outcomes, the tubularized incised plate urethroplasty (TIPU) and the dorsal inlay graft urethroplasty (DIGU) are two of the most commonly used techniques for hypospadias repair in children. However, there is a lack of consensus on which technique offers more favourable results and less added morbidity to the patient.

Aims: This study aimed to systematically compare the reported outcomes of the TIPU and DIGU techniques in an effort to determine the procedure of choice in children undergoing primary hypospadias repair.

Design: A systematic review and meta-analysis of randomized and observational studies.

Methods: An electronic database search was conducted up to May 2018. Sources included Medline, Embase, Cochrane library, CINAHL, Web of Science, and Google Scholar as well as trial registries and grey literature sources. Studies were selected if they compared the operative complications of TIPU and DIGU in children. Secondary outcomes included standardized cosmetic scores and urinary flow studies. A metaanalysis of reported complications was performed using a random-effects model.

Results: Two randomized, two prospective, and two retrospective studies met the inclusion criteria. TIPU and DIGU were performed in 350 and 267 patients respectively. Pooled analysis did not demonstrate a significant difference regarding post-operative urethrocutaneous fistula, meatal/urethral stenosis, wound dehiscence, or total complications. Subgroup analysis according to hypospadias severity did not alter initial findings. Sensitivity analysis with exclusion of retrospective studies demonstrated a significant increase in post-operative meatal/urethral stenosis and total complications after TIPU. Statistical analysis of secondary outcomes was not feasible due to insufficient data. Most studies were of low methodological quality with a high risk of bias.

Conclusions: There is no strong evidence to suggest that either technique offers more favourable outcomes. Until more robust randomized trials exist, decisions regarding the appropriate repair should be based on the surgeon’s experience and outcomes.