G. Dubrovsky1, A. Thomas2, S. Shekherdimian1, J. Dunn2 1University Of California – Los Angeles,Los Angeles, CA, USA 2Stanford University,Palo Alto, CA, USA
Introduction:
Intestinal lengthening with endoluminal springs has been well studied in animal models, and has been shown to lengthen a segment of intestine by as much as 3-fold. Springs are secured inside the intestine by surgically narrowing the intestine around the spring. This method of intestinal lengthening can be performed within a functional segment of bowel, and does not interfere with normal digestion or peristalsis. However, the amount of intestinal narrowing or plication necessary for lengthening has not been studied. The goal of this study is to determine if lengthening can be optimized by changing the amount of intestinal plication performed to secure an endoluminal spring.
Methods:
Juvenile mini-Yucatan pigs underwent surgical implantation of a nitinol spring within a segment of intestine via enterotomy that was closed. Plication or narrowing of the intestine around the spring with sutures was performed to help secure the spring within the intestine. There were three total groups of pigs; in the first group, the diameter of the intestine was reduced by 50%, in the second group it was reduced by 30%, and in the third group it was reduced by only 10% (FIGURE). Pigs were kept on a liquid diet post-operatively. 3 weeks after the original operation the pigs were euthanized and intestinal segments were examined for longitudinal lengthening and for histological changes.
Results:
All pigs tolerated the surgeries without complications. There were no cases of obstruction or perforation and all springs remained in place at the site of original implantation. While 50% plication resulted in 3-fold lengthening, 30% plication resulted in a 1.8-fold increase in length, and 10% plication resulted in a 1.3-fold increase in length. All lengthened segments showed significant increases in both the thickness of the muscularis propria as well as the depth of crypts as compared to normal segments of intestine.
Conclusion:
Intestinal plication is effective in securing springs within a segment of intestine to achieve intestinal lengthening, and the degree of plication effects the amount of lengthening that can be achieved. 50% reduction in the diameter of the bowel allows for maximal intestinal lengthening, while still avoiding bowel obstruction. These results will be important in guiding potential future therapies in the treatment of short bowel syndrome.
