A jejunal biopsy is a test to take a tiny sample of your child's jejunum.
Laparotomy showed the proximal ileum and distal jejunum had prolapsed through a tear at the rectosigmoid junction.
The duodenum is about 10 in (25 cm) long and connects the stomach and the jejunum.
The duodenum is the first part of the small intestine, extending from the valve at the bottom of the stomach that regulates stomach emptying (pylorus valve) to the second part of the small intestine (jejunum).
The malrotation, stenosis, or membranous bands are corrected surgically so that the duodenum has a normal opening and connects properly to the stomach and jejunum.