Bladder Mucosa Harvested with Holmium Laser for Treatment of Urethral Strictures: Does the Graft Have its Tissue Integrity Preserved?

Objective: The aim of this study is to evaluate the integrity and the microstructural characteristics of the bladder mucosa graft harvested using a minimally invasive technique with the Holmium laser (Ho-YAG) for the treatment of urethral stricture.

Materials and methods: We studied patients with urethral strictures greater than 2 cm, with a urethroplasty indication. The patients were submitted to urethroplasty with the dorsal onlay reconstruction by a single surgeon. After the urethral dissection we use the Ho-YAG laser with a 550µg end fire laser fiber to obtain a fragment of bladder mucosa for the graft confection. A fragment of the bladder mucosa was fixed in a 10% buffered formalin to HE and Masson's trichrome analysis for the tissue integrity. Five sections were stained, and five fields of each section were selected. We used the Image J software, version 1.46r, loaded with its own plug-in to determine tissue integrity.

Results: We studied 11 patients (Mean age= 47.64); 9 (81.8%) with bulbar stricture and 2 (18.2%) with penile stricture (mean size = 4.63mm). The mean of bladder graft size was 53.64mm and the meantime of harvesting was 47.63 minutes. The histological study of the bladder wall graft showed an organization in accordance with normal standards, with the presence of an intact urothelium in the bladder graft. The submucosal layer is preserved, joining the detrusor to the urothelium and the collagen and elastic fibers are well organized.

Conclusion: The graft harvested from the bladder uroepithelium using Ho-YAG has its histological integrity preserved, which makes this technique a viable option for reconstructive surgery. However, more studies are needed to establish its long-term efficacy and safety of this new technique.