ABSTRACT
Congenital duodenal obstruction is the most common cause
of intestinal obstruction in the newborn period, occurring in
1 in 500010000 live births.13
Duodenal obstruction is the result of intrinsic lesion,
extrinsic lesion, or a combination of both. Intrinsic duodenal
obstruction may be caused by duodenal atresia, stenosis,
diaphragm, a perforated diaphragm, or a ‘windsock’ web.
The windsock web is a duodenal membrane which is
ballooned distally as a result of peristalsis from above.4,5
Extrinsic duodenal obstruction may be caused by annular
pancreas, malrotation, or preduodenal portal vein. Although
the annular pancreas forms a constricting ring around the
second part of the duodenum (Fig. 49.1), it is not believed to
be the cause of duodenal obstruction6,7 and there is usually
an associated atresia or stenosis in patients with an annular
pancreas.810 Similarly, preduodenal portal vein has also
seldom been reported to be the cause of duodenal obstruc-
tion and it is often associated with other causes of intestinal
obstruction, such as malrotation or duodenal atresia.11,12
