Use of vascularized abdominal wall pedicle flaps to grow small bowel neomucosa.

ABSTRACT

Growing new mucosa from remnants of small bowel remaining in patients with short-bowel syndrome might offer a strategy for solving this clinical problem. We have performed a series of experiments investigating the possibility of growing rabbit ileal mucosa on vascularized pedicle flaps of abdominal wall musculature based on the inferior epigastric artery. By patching a defect of distal ileum with a skeletal muscle flap, we were able to demonstrate bowel augmentation by neomucosal ingrowth. Light and scanning electron microscopy confirmed the presence of essentially normal mucosa with well-developed villi atop the skeletal muscle pedicle flap. The mucosa was stripped from the skeletal muscle and compared with stripped mucosa from adjacent ileum in the Ussing chamber in 11 rabbits. The electrophysiologic studies showed no significant difference between normal mucosa and neomucosa in short-circuit current (Isc), potential difference or tissue conductance. The addition of 10 mM glucose resulted in similar unidirectional glucose flux and increase in Isc in both tissues. Bile salt absorption was also similar in both tissues. We conclude that neomucosa can be grown on flaps of skeletal muscle and is similar to normal mucosa by microscopic and electrophysiologic evaluation.