Duodenum malrotation

Midgut volvulus is the most dramatic consequence of intestinal malrotation. When present at birth, the classic finding on a plain film is partial obstruction of the duodenum, but evidence of complete obstruction may also be present. In such cases, it is impossible to distinguish midgut volvulus from... 

A patient with malrotation may also develop dense peritoneal bands, termed Ladd s bands, that originate in an attempt to fix the bowel. These bands extend from the cecum to the hilum of the liver, posterior peritoneum, or abdominal wall across the duodenum and can cause extrinsic duodenal obstruction. 

Obstruction due to Ladd s bands produces a Z-shaped configuration, outlining the lack of normal rotation and fixation of the duodenum. The Z-configuration may appear similar to the corkscrew of volvulus, but it does not indicate volvulus itself (Fig. 1.12). It must be stressed, however, that in most children with malrotation obstruction is caused by the volvulus with the band playing a lesser role or no roll at all (Ford et al. 1992 Torres and Ziegler 1993). 

Fig. 1.12a,b. Malrotation with z-shape of the duodenum and jejunum. Upper gastrointestinal series. Anteroposterior (a) and lateral (b) projections show a central, downward, Z course of the duodenum. No volvulus was found at surgery. Surgery demonstrated the partial obstruction to be produced by Ladd s bands... 

In the case of duodenal obstruction with similar clinical signs as atresia, but with air distal to the duodenum, intestinal malrotation should be ruled out. 

Fig. 5.6. a UGI determines normal rotation by identifying the duodenojejunal junction (ligament of Treitz). b Intestinal malrotation demonstrated with a barium enema. Localization of jejunum in right upper quadrant. The duodenum does not cross the spine... 

Fig. 9.1. Nonrotation type of intestinal malrotation. CECT at the level of the pancreatic head shows right-sided contrast-filled small bowel loops, left-sided colon, and absence of the horizontal duodenum. Note an abnormal relationship of the superior mesenteric vessels and aplasia of the uncinate process of the pancreas...

Fig. 9.2. Type 11c of intestinal malrotation The horizontal duodenum passes anteriorly to the vertically oriented superior mesenteric vessels with a normally located colon in front of it. (Reprinted with permission from Zissin et al. 1999)...

The characteristic CT findings of intestinal nonrotation include abnormal orientation of the superior mesenteric vessels, aplasia or hypoplasia of the uncinate process of the pancreas, right-sided small bowel loops, a left-sided colon, and the absence of the horizontal part of the duodenum. Vertical or reversed location of the superior mesenteric vessels is, however, not specific for intestinal malrotation. 

Fig. 12.9a,b. Small bowel malrotation. Plain radiograph demonstrating dilated stomach and first part of the duodenum in an infant with mid-gut volvulus b barium meal confirms the enormous distension of the duodenum. Note the collapsed jejunal loops... 

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