Malrotation criteria

Quote from "Pediatric Surgery (Springer Surgery Atlas)" by Prem Puri, Michael E. Höllwarth -

"Plain abdominal radiograph is often normal; features suggestive of malrotation with or without midgut volvulus are a distended stomach and proximal duodenum with a paucity of gas distally, either throughout or unilaterally. An upper gastrointestinal contrast study is the investigation of choice for any child presenting with bilious vomiting. The study should be performed urgently to look for findings characteristic of malrotation: The D-J flexure is seen right of the left vertebral pedicle and/or inferior to the pylorus. The duodenum passes caudally and anteriorly. Contrast tapering or a “corkscrew” appearance suggests obstruction and/or volvulus. Caecal position is highly variable and may be normal in up to 15% of cases of malrotation, so contrast enema is not always helpful. Abdominal ultrasound may show reversal in the relationship of the SMA to the superior mesenteric vein (SMV). In a normal situation, the SMV is located to the right of the SMA; an SMV to the left of the artery is suggestive of malrotation. Computer tomography is not indicated in infants and children."