Classification of jejunoileal atresia

Classification of jejunoileal atresia:
• Type I (mucosal web) — The lumen is obstructed by an intact diaphragm or membrane composed of mucosa and submucosa. The muscularis and serosa remain intact, resulting in no discontinuity in the bowel.
• Type II (fibrous cord) — An obvious gap in bowel continuity occurs. The proximal and distal segments are connected by a short fibrous band.
• Type IIIa (mesenteric gap defect) — A gap in bowel continuity, similar to type II, but no tissue connects the blind ends. There is usually an associated V-shaped gap in the mesentery.
• Type IIIb ("apple peel") — Proximal small bowel atresia, absence of the mid-small bowel that is normally supplied by the distal superior mesenteric artery, and a large gap in the small bowel mesentery. The small bowel distal to the atresia is foreshortened and coiled like an apple peel.
• Type IV (multiple atresias) — Multiple type II or IIIA atresias; these appear like a string of sausages. The bowel may also be foreshortened.