Novel Concept and Method of Endoscopic Urethral Stricture Treatment Using Liquid Buccal Mucosal Graft

• Published in: The Journal of urology Vol. 196; no. 6; pp. 1788 - 1795
• Main Authors: Nikolavsky, Dmitriy, Manwaring, Jared, Bratslavsky, Gennady, Caza, Tiffany, Landas, Steve, Hryniewicz-Jankowska, Anita, Kotula, Leszek
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.12.2016
• Subjects: Animals; Cystoscopy - methods; Disease Models, Animal; grafts; injections; Male; minimally invasive surgical procedures; mouth mucosa; Mouth Mucosa - transplantation; Rabbits; Transplantation, Autologous; Urethra - surgery; urethral stricture; Urethral Stricture - surgery; Urologic Surgical Procedures, Male - methods; Urology; injections; direct vision internal urethrotomy; RUG; buccal mucosa graft; liquid BMG; LBMG; urethral stricture; grafts; mouth mucosa; BMG; retrograde urethrogram; minimally invasive surgical procedures; DVIU
• ISSN: 0022-5347; 1527-3792
• DOI: 10.1016/j.juro.2016.05.028

Purpose We describe a novel method of urethral stricture treatment using liquid buccal mucosal grafts to augment direct vision internal urethrotomy. Materials and Methods A rabbit stricture model was used to test this method. In phase 1 the concept of endoscopic liquid buccal mucosal graft implantation was tested by performing direct vision internal urethrotomy in 3 rabbits with immediate intraurethral injection of autologous liquid buccal mucosal grafts suspended in fibrin glue. Animals were sacrificed at 2 to 3 weeks and the urethras were examined for the presence of buccal mucosa engraftment. In phase 2 strictures were induced by electroresection in 9 rabbits divided into 2 groups, including 1) 6 rabbits treated with direct vision internal urethrotomy and liquid buccal mucosal grafts, and 2) 3 controls that underwent direct vision internal urethrotomy and injection of fibrin glue only. Two treated and 1 control animals were sacrificed at 8, 16 and 24 weeks each. Prior to sacrifice the animals underwent retrograde urethrograms and urethroscopy. Histological specimens were examined for the presence of buccal mucosal engraftment. Results In phase 1, 2 of the 3 rabbits demonstrated engraftment of buccal mucosa in the urethra after injection of liquid buccal mucosal grafts. In phase 2 all 6 treated animals demonstrated engraftment and showed resolution/improvement of strictures on retrograde urethrograms and urethroscopy. Controls had no buccal engraftment and showed fibrosis and chronic inflammation. One of the 3 controls had persistent stricture on retrograde urethrograms and cystoscopy. Conclusions This proof of concept study demonstrated the feasibility of using liquid buccal mucosal grafts for endoscopic urethral stricture repair. Such a method may allow for wide application of this novel concept of using liquid buccal mucosal grafts to augment direct vision internal urethrotomy.