Spiral intestinal lengthening and tailoring - first in vivo study.

INTRODUCTION

Spiral Intestinal Lengthening and Tailoring (SILT) offers a new opportunity for the surgical treatment of short bowel syndrome. SILT requires less manipulation on the mesentery than the Bianchi procedure and does not alter the orientation of the muscle fibers like serial transverse enteroplasty (STEP). This study reports the first SILT results in a surviving animal model.

MATERIAL AND METHODS

Vietnamese minipigs (n=6) underwent interposition of a reversed intestinal segment to produce proximal small bowel dilation. Five weeks later the reversed segment was resected, and the wall of the dilated intestine was cut spirally at 45°-60° to its longitudinal axis. The bowel was lengthened longitudinally, and the spiral shaped intestinal wound was sutured. Five weeks later, the animals were explored, and the lengthened segments were measured. Haematoxylin and eosin, picrosirius, neuron specific enolase, S-100, C-kit, and immunohistochemistry were performed.

RESULTS

Mean lengthening was 74.8% ± 29.5% and mean tailoring (lumen reduction) was 56.25% ± 18.8%. No instances of necrosis, perforation, suture break down, or peritonitis were observed in 6/6 animals. Four of six animals recovered uneventfully with viable lengthened segments. Statistical analysis showed no significant difference in length (p=0,078) and width (p=0,182) after 5 weeks. Two animals developed bowel obstruction due to narrowed lumen, adhesion, and strangulation after 14 and 24 days of surgery. In both animals the lumen was tailored by more than 70% to less than 1.5 cm diameter. The mucosa and the muscle layers in the operated segment had become hypertrophic, but the orientation of the circular and longitudinal muscle fibres remained normal after the SILT procedure. There were no signs of chronic ischemia or collagen accumulation after the SILT. The myenteric and submucosal plexuses and the Cajal cell network appeared normal.

CONCLUSION

The bowel remained viable macroscopically and microscopically after SILT, such that SILT may be an alternative or an addition to the present technical repertoire of intestinal lengthening. However the limitations of tailoring should be kept in mind.