Benefits of accurate and guided endoureterotomy versus ureteral balloon dilatation in the management of ureteral strictures—comparative animal study

BACKGROUND: Endoscopic treatment of ureteral strictures provides a minimally invasive approach with a shorter hospital stay and less postoperative pain. There are different therapeutic options, the dilatation balloon and endoureterotomy with holmium yttrium-aluminum-garnet (Ho:YAG) laser are the most used. To assess histological changes after endoureterotomy in the ureteral stricture treatment comparing Ho:YAG laser endoureterotomy versus balloon dilatation endoureterotomy. METHODS: The subjects used were a total of 48 female pigs. The initial assessment consisted of an endoscopic, nephrosonographic, and contrast fluoroscopic evaluation of the urinary tract. Subsequently, a model of ureteral stricture was performed. Three weeks later, the ureteral stricture was diagnosed and treated. Then animals were randomly assigned to two groups (group A, Balloon dilatation endoureterotomy and group B, Holmium laser retrograde endoureterotomy) in which a double-pigtail ureteral stent was placed for 3 weeks. Follow-up assessments were performed at 3–6 weeks. The final follow-up was completed at 5 months and included the pathological study. RESULTS: In terms of therapeutic effectiveness, the overall success was 81.2%. The success rate was 91.7% in group B and 70.8%in group A without statistical significance. No evidence of vesicoureteral reflux nor urinary tract anomalies were observed. Histological assessment showed statistical significance in overall score, lamina propria fibrosis and serosal alterations in group A with higher histological changes. CONCLUSIONS: The overall histopathological score after ureteral stricture treatment in an animal model showed better remodeling of incised ureteral wall healing after Ho:YAG laser endoureterotomy. Laser endoureterotomy tends to have higher success rate compared to balloon dilatation.