We present two cases of windsock deformity; both were rare in location and one had a rare associated anomaly. In the first case, the windsock was observed in the fourth part of duodenum, causing partial intestinal obstruction. In the second case, the windsock was located in the third part of the duodenum.

Windsock deformity (WD) is a rare anomaly. Fewer than 100 cases of WD have been reported[1–3]. The second part of the duodenum is the most common site of WD[1]. Associated anomalies, such as intestinal malrotation and a preduodenal portal vein, are well known. Presentation of a fenestrated duodenal web with acute pancreatitis has also been reported[4]. We report two cases of windsock deformity; both were rare in location and one had a rare associated anomaly.

Only 100 cases of WD have been reported in the literature[1–3]. The second part of the duodenum is the most common site, representing 85% to 90% of all WD cases. The third and fourth parts of the duodenum represent 20% and 10% of WD cases, respectively[15].

The WD in our first case was in the fourth part of the duodenum, which is a very rare location. The duodenum undergoes a solid phase; between the eighth and tenth week of gestation, the duodenal lumen is re-established by the gathering of vacuoles, and re-canalization occurs. Insults during this crucial period of development are believed to result in a failure of re-canalization and consequent atresia, stenosis and webs[56]. The resultant obstruction causes dilatation in the proximal duodenum and stomach, as well as hypertrophy and distention of pylorus[5].

Abdominal distention and vomiting were common complaints in each of our cases. Our first case was followed up by a pediatrician with diagnoses of constipation and growth failure. The great majority of individuals with WD are asymptomatic. A significant proportion of patients have a later onset of symptoms, and in some, the diagnosis is delayed until adulthood[7]. Clinical presentation may be characterized by nonspecific abdominal symptoms. Abdominal discomfort is usually located in the epigastria, right upper abdomen or umbilical area, and is made worse or brought on by eating and relieved by vomiting, belching or assuming a certain posture[15].

WD can be an incidental finding of upper gastrointestinal barium examination. In the second case, a pre-operative upper gastrointestinal study revealed the intraduodenal web. One of the most important features of duodenal diverticulum is the retention of barium in the sac. Barium retention for 6 or more hours is diagnostic[13].

Associated anomalies, such as intestinal malrotation and a preduodenal portal vein, are well recognized. Pancreatitis has also been reported in individuals with intraluminal duodenal diverticula[45]. Superior mesenteric artery syndrome is a very rare condition in childhood, most frequently resulting in duodenal obstruction in the adult population[12]. Bleeding from ulcers at the diverticulum[8], obstruction from gallstones[9] and marbles[3], as well as cholangitis[10] have been described. Hepatic hemangioma is an unusual finding in the pediatric population and is more common in older children and adolescents than in neonates and infants[111]. We discovered, incidentally, the hemangioma during US for the diagnosis of intestinal pathology.

Duodenotomy with web excision was performed in both of our cases. Two basic options for the repair of duodenal obstruction secondary to a web or atresia are presented: duodenoduodenostomy and duodenotomy with excision of the web. The web should be defined with the aid of a tube trough in the stomach, and the ampulla of Vater should be carefully identified prior to excision. The advent of improved pediatric flexible fiberoptic endoscopes and fiberoptic laser technology makes endoscopic ablation of duodenal webs and windsocks in the newborn possible[59].

We aimed to present two cases of WD showing rare locations in the fourth and third part of the duodenum from the same institution.