A Prospective Study of Outcomes After Tubularized Incised Plate (TIP) Urethroplasty: a Multivariable Analysis of Prognostic Factors in Children 1-3 Years Old

Background: Tubularized incised plate (TIP) urethroplasty as the most common hypospadias repair method, aims to achieve normal functioning of the penis along with cosmetic reconstruction. However, there are remaining questions toward anatomical prognostic factors affecting the results of surgery. Lack of age-matched controls or controlling for meatal location, employment of several surgical techniques or multiple surgeons, or age heterogeneity of the study population are the problems affected the results of the current body of literature. Objective: This prospective study aimed to evaluate the preoperative factors to predict future complications associated with hypospadias repair outcomes in males aged between 1-3 years and performed by a single surgeon with employing multivariate analysis. Patients and methods: A prospective cohort of 101 males aging from 1 to 3 years with distal to mid-shaft hypospadias were consecutively selected for TIP repair. The urethral plate dimensions in erect and flaccid states, penile length, glans diameter, and chordee were evaluated individually before reconstruction. After surgery and during follow-up visits, the subsequent transient and persistent complications were recorded. Results: Postoperatively, the acute transient events were observed in 42 cases (41.6%) and the persistent complications in 16 cases (15.8%). The uncomplicated group had a higher percentage of patients with distal meatal location than the complicated group (P=0.01%). Furthermore, fistula formation was notably higher in the group with acute surgical site infection (P<0.001). The analysis also showed the width of the urethral plate to be inversely associated with the development of complications (P=0.03). Conclusion: By performing TIP by a single surgeon on a homogenous study population and eliminating the impact of severe chordee as a potential cofounding variable, this study prospectively found that out of the anatomical specifications, pre- and postoperative factors, the urethral meatus location was the only significant and independent predictor of the development of complications in young children with midshaft to distal hypospadias. Finally based on the inverse association of width with the complications we hypostatized that a combination of urethral width and depth should be considered in the investigation of prognostic factors for hypospadias repair outcomes.