Colonic Atresia Etiology: in-utero vascular accidentEnema: microcolon that is shortened in appearance Cases of Colonic Atresia The AXR (left) shows a distal bowel obstruction. The enema (right) shows a microcolon with opacification of only the descending colon. Surgical images show numerous loops of small bowel which are dilated, thickened and inflamed along with an extremely dilated ascending colon which is at the lower part of the left image and to the left side of the right image. An area of atresia was identified at approximately the hepatic flexure. The downstream colon (not shown) had the appearance of a microcolon. On the right image, the forceps are on the dilated appendix.