Gastric adaptive changes following experimental gastroplasty.
To study the adaptive response of the stomach secondary to partial obstruction imposed by gastroplasty, groups of rabbits with calibrated midgastric constrictions created as a stoma (unreinforced, Group II), as a short channel (Group III), or as a stoma reinforced with polypropylene mesh (Group IV), were compared to controls (Group I). It was found that the unreinforced stoma dilated rapidly while the pouch dilated moderately. In both the channel and reinforced stomas, the pouch dilated markedly. Increased fibrosis was found inside of the polypropylene banding, resulting in a significant incidence of luminal obstruction. The channel dilated in stages, affecting the proximal end first; but obstructive effect remained as long as part of the channel was undilated. We conclude that a narrow stoma is incompatible with a small pouch over time. Since anatomic specifications do not define function, both function (such as emptying) and adaptive changes should be studied in animal models before introduction of any new gastric limiting procedures into clinical practice.