A Multicenter Randomized Controlled Trial Comparing Platelet-Rich Fibrin and Ventral Dartos Flap as Intermediate Layers in Tabularized Incised Plate (TIP) Urethroplasty for Distal Hypospadias With Mild Penile Curvature (PRF)

National Children's Medical Center, Uzbekistan

Status: Invitation-only

Conditions: Functional Outcomes; Hypospadias Repair; Tubularized Incised Plate; Cosmetic Outcomes; Distal Hypospadias; Hypospadias; PRF; Fistula Stenosis

Treatments: Procedure: Group B: Ventral dartos flap rotated over neourethra; Procedure: - Group A: Platelet-rich fibrin membrane prepared intraoperatively and applied over neourethra

Study type: Interventional

Funder types: Other

Identifiers

NCT07045545

0620251

Details and patient eligibility

About

Distal hypospadias is the most common form of hypospadias. The Tubularized Incised Plate (TIP) repair is the standard surgical technique for this condition; however, complications such as fistula formation and meatal stenosis remain concerns. These complications are often influenced by the choice of intermediate tissue layer used to reinforce the neourethra. The traditional ventral dartos flap is effective but can be technically challenging and may result in a bulky tissue layer.

Platelet-rich fibrin (PRF) is an autologous, growth factor-rich biological material that has shown promise in tissue regeneration and healing. It is easy to prepare intraoperatively and may serve as a biological reinforcement to reduce postoperative complications.

This study aims to provide high-quality evidence comparing the effectiveness of PRF versus the ventral dartos flap in patients with distal hypospadias, specifically those with Grade 1 urethral defects and minimal penile curvature, using a stratified study population to ensure balanced groups.

Full description

This randomized controlled trial aims to compare the incidence of urethrocutaneous fistula at a minimum of 6 months postoperatively between two intermediate layers used in hypospadias repair: platelet-rich fibrin (PRF) membrane and ventral dartos flap. The study will also evaluate secondary outcomes, including rates of meatal stenosis, urethral stricture, other postoperative complications, and cosmetic outcomes assessed by standardized photographs and blinded expert scoring.

Study Design and Setting:

This prospective, multicenter, single-blinded randomized controlled trial will be conducted at centers in Tashkent, Uzbekistan, and Jakarta, Indonesia. A total of 140 patients (70 per group) will be enrolled, with randomization stratified by urethral plate score and center to ensure balanced groups.

Participants:

Children aged 6 months to 5 years with primary distal hypospadias (Grade 1, Abbas classification) or redo distal hypospadias (Grade 1, Abbas classification), with penile curvature less than 30° after degloving (measured as per Abbas, 2022), will be included. Exclusion criteria include previous hypospadias surgery, proximal hypospadias, penile curvature ≥30°, or syndromic anomalies/coagulopathies.

Interventions:

Participants will undergo tubularized incised plate (TIP) or glanuloplasty TIP (GTIP) urethroplasty performed by experienced pediatric urologists using standardized techniques.

Group A: Application of autologous platelet-rich fibrin membrane over the neourethra. PRF will be prepared intraoperatively by drawing 10 mL of peripheral blood, centrifuging at 3000 rpm for 10 minutes, extracting the PRF clot, compressing it into a membrane, and securing it over the neourethra with absorbable sutures.

Group B: Rotation of a ventral dartos flap over the neourethra.

Intraoperative PRF Preparation:

Blood will be collected into sterile glass tubes without anticoagulants, centrifuged immediately, and the PRF membrane prepared as described. The membrane will be placed over the neourethra before glans closure, secured laterally, and the skin closure completed in standard fashion.

Stratification:

Participants will be stratified based on urethral plate characteristics using a validated scoring system before randomization to ensure anatomical balance.

Follow-Up:

Patients will be assessed at 1, 3, and 6 months postoperatively for complications (fistula, stenosis, etc.), neomeatus function, and cosmetic appearance. Digital photographs will be evaluated by two blinded pediatric urologists, and cosmetic outcomes will be scored using the HOSE system.

Data Management and Analysis:

All data will be anonymized and stored securely. Statistical analysis will be performed using SPSS v22, applying appropriate tests for categorical and continuous variables, with multivariate regression if necessary.

Enrollment: 5 estimated patients

Sex: All

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

1. Primary and complex distal hypospadias (Grade 1, Abbas classification)
2. Penile curvature <30° after degloving (Methodology of curvature measurement: Abbas T. O. (2022).
3. Children aged 6 months to 5 years

Exclusion criteria

1. Previous hypospadias surgery
2. Proximal hypospadias
3. Penile curvature ≥30°
4. Syndromic anomalies or coagulopathy

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

---

5 participants in 2 patient groups

Group A: PRF applied over neourethra;

Experimental group

Description:

* In patients randomized to the PRF group (Group A), autologous platelet-rich fibrin will be prepared intraoperatively using the following standardized protocol: * Approximately 10 minutes before completion of urethroplasty, a 5-10 mL peripheral blood sample to be drawn from the cephalic vein under sterile conditions. The blood to be immediately transferred into a plain sterile glass tube without anticoagulants or additives. Centrifugation to be performed at 3000 rpm (approximately 400×g) for 10 minutes using a bench-top centrifuge. * Following centrifugation, three distinct layers were formed: 1. Acellular plasma (top) 2. Platelet-rich fibrin clot (middle) 3. Red blood cells (bottom) * The PRF clot to be carefully extracted using sterile forceps , and residual red blood cells were gently separated to ensure a clean PRF membrane. The PRF clot will then gently compressed between saline-soaked sterile gauze to form a pliable membrane suitable for surgical application.

Treatment:

Procedure: - Group A: Platelet-rich fibrin membrane prepared intraoperatively and applied over neourethra

Group B: Ventral dartos flap rotated over neourethra

Active Comparator group

Description:

Participants in this arm will undergo hypospadias repair with the application of a ventral dartos fascia flap. The procedure involves elevating a vascularized flap of ventral dartos fascia from the penile shaft, rotating it over the neourethra to provide additional tissue coverage and promote healing. This flap helps in reducing the risk of fistula formation and enhances vascular support to the neourethra. The surgical steps include dissecting the dartos fascia carefully, rotating it over the neourethral reconstruction, and securing it in place, followed by standard postoperative care and follow-up.

Treatment:

Procedure: Group B: Ventral dartos flap rotated over neourethra