3. When the stomach appears small or absent, it is important to allow sufficient
time for it to fill, in case it has recently emptied. Generally, the stomach will fill
during a 30 minute examination.
4.
5.
6.
7. The classic “double bubble” sign of a second echo-lucent mass medial to the stomach
(in a transverse view of fetal abdomen) is considered diagnostic of duodenal
obstruction.
This image represents the dilated duodenum proximal to the atretic area.
8.
9. Jejunal atresias, however, are more likely to be multiple and less often
associated with in utero perforation than ileal atresias, likely because of the
lower compliance of the ileum.
Diagnosis of jejunoileal obstructionis based on dilated loops of bowel, most
frequently without a dilated stomach and sometimes with hyperperistalsis.
If peristalsis is not observed, dilated small bowel can be difficult to distinguish
from dilated colon.
The diagnosis of jejunoileal atresia is typically not made until late in the second
trimester, when the bowel dilates.
Polyhydramnios is less common in lower bowel obstructions than in duodenal
atresia, not occurring in any reported ileal atresias,but occurring in one third of
jejunal atresias.
