Liquid buccal mucosa graft endoscopic urethroplasty: a validation animal study.

To validate a novel method of urethral stricture treatment using liquid buccal mucosal grafts (LBMG) to augment direct vision internal urethrotomy (DVIU) in an animal model.

A rabbit stricture model was used to test this method. Strictures were induced in 26 rabbits using electroresection of urethral epithelium. The animals were randomized into two groups: Group-1, treated with DVIU and LBMG in fibrin glue, and Group-2, DVIU with fibrin glue only. LBMG was prepared by suspension of mechanically minced buccal mucosa micrografts in fibrin glue. This LBMG-fibrin glue mixture was later injected into the urethrotomies of Group-1 animals. All animals were killed at 24 weeks after repeat retrograde urethrogram (RUG) and urethroscopy by surgeon blinded to the treatment arm. Radiographic images and histological specimens were reviewed by a radiologist and a pathologist, respectively, blinded to the treatment arm. Stricture treatment was considered a success if a diameter measured on RUG increased by ≥ 50% compared to pre-treatment RUG diameter. Histological specimens were assessed for the presence of BMG engraftment.

In Group-1, 8/12(67%) animals demonstrated engraftment of LBMG, compared to none in Group-2 (p = 0.0005). 7/12(58%) in Group-1 showed radiographic resolution/improvement of strictures compared to 5/13 Group-2 rabbits (38%, p = 0.145). The median percent change for the Group-1 was 59%, compared to 41.6% for Group-2 (p = 0.29).

This proof-of-concept study demonstrates feasibility of LBMG for endoscopic urethral stricture repairs. Further studies are needed to establish the role of this novel concept in treatment of urethral strictures.

World journal of urology. 2019 Jun 07 [Epub ahead of print]

Kathryn A Scott, Guanqun Li, Jared Manwaring, Daniela A Nikolavsky, Yelena Fudym, Tiffany Caza, Zain Badar, Nicole Taylor, Gennady Bratslavsky, Leszek Kotula, Dmitriy Nikolavsky

Department of Urology, State University of New York Upstate Medical University, Syracuse, NY, USA., Department of Pathology, State University of New York Upstate Medical University, Syracuse, NY, USA., Department of Radiology, State University of New York Upstate Medical University, Syracuse, NY, USA., Department of Urology, State University of New York Upstate Medical University, Syracuse, NY, USA. .