Ureterorectal diversion with rectal augmentation. Morphological and manometric study in the dog

Area of Science:

• Urology
• Surgical Innovation
• Gastroenterology

Background:

• Uretersigmoidostomy is associated with high complication rates, leading to its abandonment.
• A novel ureterorectal diversion model was developed to improve rectal capacity and reduce pressure.

Purpose of the Study:

• To assess the feasibility of a new ureterorectal diversion technique using an ileal segment in adult dogs.
• To evaluate the impact of this diversion on rectal physiology, capacity, and pressure.

Main Methods:

• 12 Beagle dogs underwent ileal segment ureterorectal diversion, with one ureter implanted and the other serving as a control.
• Rectal pressure and elasticity were measured preoperatively and 3 months postoperatively using balloon distension.
• Radiographic studies and autopsy examinations were performed to assess the augmented rectal space and ureterorectal anastomosis.

Main Results:

• Rectal augmentation significantly decreased intrarectal pressure by 50% (P < 0.01) for a given distension volume.
• The rectal wall's elasticity remained unchanged, but reservoir capacity was effectively increased.
• Ureteroileal implantation patency was observed in 2 out of 7 cases, with associated pyelonephritis in the right kidneys.

Conclusions:

• The novel ureterorectal diversion effectively increases rectal capacity and decreases pressure, offering a potential alternative to traditional methods.
• Significant technical challenges with ureteroileal implantation in the canine model hindered a complete assessment of the reimplantation technique's efficacy.