Fetal Gastrointestinal Tract: US and MR

Abstract

Evaluating the normal anatomy and detecting an abnormality of fetal GI tract is based on sonography: it is an evidence. However, the prenatal US demonstrates true insufficiencies for diagnosing GI tract malformation (Corteville et al. 1996; Haeusler et al. 2002; Phelps et al. 1997). Actually, sonographic imaging is only able to detect a bowel loop dilatation or hyperechogenic bowel. Rarely, etiological diagnosis may be done, such as Down syndrome with duodenal stenosis. Obviously, even where the mechanism of bowel atresia is unknown, the infant will be operated on in the first days of life. Nevertheless, a simple dilatation may refer to a more severe disorder: bowel volvulus, multiple atresia, apple peel syndrome. A volvulus may impair the bowel vitality, and the diagnostic emergency cannot be assessed with US. In the same way, while US may show and measure a normal fetal colon, it is actually unable to affirm a microcolon, which is an extremely interesting etiological marker: small or large bowel atresia, meconium ileus, megacystis-microcolon-intestinal hypoperistalsis syndrome.