Mesenteric neovascularization with distraction-induced intestinal growth: enterogenesis.

BACKGROUND

Distraction-induced enterogenesis, whereby the intestine lengthens with application of linear forces, is an emerging area which may provide a unique treatment for short bowel syndrome. With an increase in overall tissue mass, there is an increase in oxygen and nutrient demand. We hypothesized that a neovascularization within the mesentery is necessary to support the growing small bowel.

METHODS

A curvilinear hydraulic device was used to induce growth within the small bowel of Yorkshire pigs, and the intestine was harvested after 14 days. High-resolution gross pictures were recorded of the mesentery at implantation and at harvest, and CT imaging of the bowel and mesentery was performed at harvest after dye injection.

RESULTS

After 2 weeks of distraction, an average of 72.5 % (8.7 cm) bowel lengthening was achieved. Gross images of the mesentery between major vessels showed a blossoming of the microvasculature and this was confirmed by CT imaging with 3D reconstruction. Mesenteric sample taken from the distracted segment had a fourfold increase in the volume of microvasculature versus controls.

CONCLUSION

Enterogenesis results not only in increased bowel length, but also significant increase in the mesenteric microvascularity. Presumably, this sustains the lengthened segment after application of longitudinal forces.