Seromuscular gastrocystoplasty in dogs.

Introduction: The aim of this study was to investigate the feasibility of seromuscular gastrocystoplasty (SGCP) in an animal model and to compare it to conventional gastrocystoplasty (CGCP).

Materials And Methods: CGCP and SGCP (using gastric segments without mucosa) were each performed in 6 dogs. In both procedures, two-thirds of the dome of the bladder were excised and the gastric segment anastomosed to the bladder remnant. Cystography, cystomanometry, measurements of urine pH, and gross and microscopic pathological studies were carried out preoperatively, and postoperatively, at 6 and 12 weeks.

Results: All seromuscular gastric segments proved viable, and 6 weeks after the operation they were covered by a thin layer of transitional epithelium, which had gradually thickened by the end of the 12-week follow-up. There was no difference in bladder capacity and compliance between the two groups, however, fasting urinary pH values were higher (less acidic) in the SGCP group.

Conclusions: Stripping off the mucosa of the gastric segment appears to stop hydrochloric acid secretion, thereby lessening the possible risk of ulceration, perforation, dysuria-haematuria, metaplasia and malignancy. The uroepithelium overgrowth of the seromuscular gastric segments might provide a more physiological neo-bladder than when using full-thickness gastrocystoplasty.