Abdominal wall incision with or without exteriorization of bowel: results from a fetal lamb model for the embryogenesis of gastroschisis.

INTRODUCTION

The embryogenesis of gastroschisis is not completely understood. The aim of our study was to evaluate the impact of a simple abdominal wall defect versus a defect including eviscerated intestine or omentum for the development of gastroschisis in a fetal lamb model.

MATERIAL AND

METHODS

At mid-gestation (day 77) an abdominal wall defect was fetoscopically created with three different approaches in 19 German blackhead sheep. The intestine was eviscerated in 7 fetuses (group 1). The peritoneum was incised and a patch of the omentum pulled through the incision in 5 fetuses (group 2). In 7 fetuses (group 3) the skin and rectus muscle were incised until the peritoneum was visible. In this group, no abdominal contents were exteriorized and the peritoneum was left intact. A second fetoscopic procedure was performed 21 days later, assessing the condition and extension of eviscerated bowel. The fetus was retrieved by Cesarean section on day 132 and evaluated.

RESULTS

The second fetoscopy acting as a control for the creation of gastroschisis demonstrated eviscerated and inflamed intestine in all 3 groups. The amount of eviscerated intestine did not appear to depend on the size of the defect nor on its duration.

DISCUSSION: It appears that a simple incision of the abdominal wall with intact peritoneum is sufficient for the development of gastroschisis in a fetal sheep model. This finding may improve the understanding of the etiology of gastroschisis.