Determination of the time required for appropriate chemical de-epithelialization of an ileal segment for cystoplasty: an animal model.

Unlabelled: Another group of authors from Iran attempted experimentally to determine the required time for the appropriate enzymatic treatment of the ideal segment to complete de-epithelialization, thus reducing its absorptive function. They found that 25 min of enzymatic treatment of the ideal segment was adequate for this, and that it was recommended from their experimental study for cystoplasty.

Objectives: To determine the time required for the appropriate enzymatic treatment of an ileal segment to de-epithelialize its mucosa and to reduce its absorptive function for cystoplasty in dogs.

Materials And Methods: Twenty-one adult female Persian mixed-breed dogs were divided into seven equal groups: group 1 (negative control group) had no ileocystoplasty; group 2 (positive control group) had a routine ileocystoplasty with no enzymatic treatment of the ileal segment; and groups 3-7 had an ileocystoplasty with 5, 10, 15, 20 or 25 min, respectively, of enzymatic treatment of the ileal segment with collagenase and trypsin. The seven groups were then compared for haematological, biochemical and histological changes, and glucose reabsorption assessed using a glucose-absorption test.

Results: No dogs showed any signs of metabolic disturbances, biochemical and haematological changes. There were significant differences in blood glucose level (BGL) for the groups at different times after the glucose-absorption test, but a pair-wise comparison showed significant differences in BGL between group 1 and the other groups, except group 7. The degree of histopathological change was associated with the duration of enzymatic treatment, in that changes were more prominent in group 7. There was no shrinkage or collagen deposition.

Conclusions: In these conditions, 25 min of enzymatic treatment of the ileal segment is sufficient to remove the absorptive function of the augmented bladder, and is recommended for cystoplasty in dogs.