The creation of a small bowel pouch by tissue expansion--an experimental study in pigs

Tissue expanders (inflatable silicone balloons) were implanted into a bypassed ileum segment of seven pigs and consecutively filled over 8 to 12 weeks. The mean increase of the volume of the small bowel loops was 12 fold with a maximum of 22.8 times the original volume. The final volume 9 weeks after expander removal still presented an increase of 500%. Histologically there was an increase of the thickness of all layers of the bowel wall, especially in the tunica muscularis. The mucosa showed a value above normal in mean in vitro 14C-resorption capacity per surface area in the reintegrated bowel. Possible clinical applications of the augmentation of the gut by expansion as a rectum substitute after proctocolectomy, as a urinary bladder or stomach substitute, and for the treatment of short bowel syndrome are discussed.