Liquid Buccal Mucosa Graft Urethroplasty

Background and Rationale There are two definitive treatment options for urethral strictures: DVIU and open urethroplasty. DVIU is an endoscopic procedure considered to be minimally invasive, but also with a high failure rate of 60-92%. The repeated DVIUs are reported to have even higher failure rates. On the other hand, open urethroplasty, considered a gold standard for reconstruction, is invasive, requires incision of the perineum or urethra, leaves a life-long scar, and has long term success rates of 74-95%. The details of DVIU and open urethroplasty are discussed below.

DVIU involves passing a cystoscope into the urethra to the level of stricture and incising the stricture longitudinally to create a wide passage to the level of normal urethra on the proximal side. The hope is to cut through the scar to the level of healthy underlying tissue and in the process of healing to populate the cut surface with healthy urethral epithelium (or at least to stabilize the scar in open configuration). In most cases, the scarring recurs faster than epithelization and most strictures recur after DVIU within 7-8 months. Studies show the strictures after traditional repeat DVIU are longer and require more involved reconstruction than strictures in patients without prior instrumentation.

Open urethroplasty for urethral strictures or bladder neck contractures usually involves longitudinal incision of the urethra (from outside in) and augmentation of the incised part with a strip of harvested Buccal Mucosal Graft (BMG). The goal of the operation is to create a wide urethral lumen for the patient to be able to pass urine without obstruction.

The first step of the procedure for DVIU and open reconstruction are nearly the same: a longitudinal incision of the scarred portion of the urethra. The difference is in the second part: covering the defect with buccal mucosal graft as in open urethroplasty vs leaving the incision uncovered and exposed to passage of urine.

Investigators of this study hereby propose to combine the minimally invasive technique of the DVIU with the technique of augmenting the incised stricture (or bladder neck contracture) using buccal mucosal graft placed endoscopically by means of application of liquid suspended graft. A similar, but more invasive technique was reported by Seith et al in 2012 performed in 12 patients with the exception of need for small open perineal incision for graft fixation. A purely endoscopic skin graft placement into urethra was reported by Naude in 1998 in 53 patients with 95% success rate at 2 years follow up. While he has not made actual incisions, his approach required percutaneous perineal needle placement for graft delivery and a specialized device for graft delivery and graft fixation. The procedure proposed for current trial is purely endoscopic with buccal graft placement and fixation augmented by fibrin glue. This type of fibrin glue sealant is readily available and widely used in General Surgery, Plastic Surgery and in Urology specifically for urethral reconstruction). This will allow for significantly less invasive procedure, shorter procedure time, absence of traditional perineal incision or needle puncture, and earlier return home (same day vs 1-3 days), earlier catheter removal (5-7 days vs 21 days) and earlier return to regular activities (1 week vs 6 weeks).

Overall, the aim is to improve the outcomes of traditional endoscopic procedure while eliminating morbidity of the open reconstruction with added benefits of earlier convalescence and health care savings from decreased surgical morbidity and shortened hospital stay.