Clinical History
This patient presented clinically with signs of an upper small bowel obstruction. A congenital duodenal obstruction was shown using radiology.
Imaging Findings
The patient was admitted to the hospital with severe vomiting and a weight loss for the past six months. In a small bowel follow-through, done five months earlier, a delay of passage in the barium
through the small bowel had been observed. A repeat small bowel series showed gastric hyperperistalsis and a dilatation of the first and second part of the duodenum, with a delay in the further
passage of barium (Fig. 1a,1b). After a change in the patient’s position, the barium entered the distal duodenum. The proximal duodenal dilatation persisted. On a spiral CT-scan five days
later, a marked dilatation of the proximal duodenum was apparent with tapering of the third part of the duodenum (Fig. 2a ). Intraluminally, a thin layer of gas adjacent to a membranous structure was
noted (Fig. 2b). An endoscopic examination performed a day later showed a dilatation of the proximal duodenum and a membrane in the third part of the duodenum having a narrow central aperture (Fig.
3a ). Bile-stained food remnants were seen.
Discussion
The imaging findings are typical of a congenital duodenal web or an intraluminal duodenal diverticulum. This disorder usually presents in neonates or young infants and then appears as a curvilinear
defect extending across the lumen of the duodenum. Typically, a distension of the duodenal bulb is noted, and the appearance in the neonate can be indistinguishable from a duodenal atresia. With the
stretching of the web, a so-called “windsock appearance“ can be demonstrated. The passage of food is possible through an eccentric defect, and consequently, the presentation can be
delayed. The adult presentation of this disorder is described with pancreatitis, which most likely follows a reflux in the pancreatic duct, as the web is usually located inferior to the
hepatopancreatic ampulla. The CT-appearance in this case, showing a thin layer of gas adjacent to the diverticulum (Fig. 2b), seems to be pathognomonic [1], but has been described only once
previously in the literature. The treatment consists of a surgical or an endoscopic removal of the diverticulum. A subsequent thorough imaging of the whole bowel is mandatory, because this condition
can be associated with other anomalies such as the presence of duodenal bands or diverticulae elsewhere in the bowel. This case, with a late presentation of a serious and correctable congenital
anomaly, underlines how important it is for all radiologists to recognise paediatric conditions presenting in adulthood.
Differential Diagnosis List