Ileo-colon-rectoplasty. An experimental morpho-functional study on the pig.

A small bowel loop was interposed, isoperistaltically or pouch-shaped between colon and rectum, (ileo-colon-rectoplasty) in 8 pigs to clarify whether the small intestine can push the semi-solid and septic content of the colon, and whether the function and morphology of the loop are modified with respect to the original. A radiographic and histologic study was performed 6 months after the operation. The structural modifications of the interposed small bowel consist of disappearance of folds, villous atrophy, superficial appearance of the glandular crypts, and, only in the isoperistaltic loop, hypertrophy of the muscular layers. Any modification in the morphologic aspect of the pouch has not been observed, as shown by the radiographic barium enema. Therefore the mucosa of the grafted ileum suffered an architectural change caused from the contact with the fecal material. The lack of structural modifications of the muscular layers and the dimensions of the above colon of the interposed ileal pouch represents an indirect proof of the correct function of reservoir ejection. The experimental results obtained confirm the applicability of this technique in the reconstruction of transit after wide resection of the left colon and rectum, for technical reasons, in man.