To investigate the ability of MRI to diagnose fetal bowel malposition, regardless of ultrasound data. Retrospective study of all non CNS fetal MRI performed in our department from January 2005 to January 2014. Were analyzed the following data: reason for of MRI, GA at MRI, position of the stomach and jejunum in T2. Position of the jejunum was defined as normal if in the left flank below the stomach and abnormal otherwise, therefore classified into 3 groups : intra -thoracic (A), extra- fetal (B) and abnormal intrafetal (C). The position of the jejunum was studied by two independent operators. Antenatal data were correlated to postnatal imaging, surgical or autopsy findings. 709 fetal MRI were performed during this period. The mean GA at MRI was 30 WG (22 min - 37 max). In 64 cases (9%) jejunum was absent from the sub gastric area in the left flank on T2-weighted images. Forty -one fetuses (64 %) had a left diaphragmatic hernia with intrathoracic position of the proximal jejunum (group A). In 11 cases (17%), jejunum was extrafetal due to gastroschisis (group B). In 12 cases (19%) intra -abdominal proximal jejunum was in an abnormal position, i.e. in the middle or right flank, with a normally positioned stomach ( group C). In only 2 cases of group C (16.6%), gastrointestinal abnormality was suspected on ultrasound. The two operators were concordant in 100 % of cases. All diagnoses of groups A and B (52 cases) were confirmed postnatally or at autopsy. In 10 cases (83%) of group C, malposition was also confirmed postnatally while it had not been suspected during prenatal ultrasounds. One case had a right jejunal deviation caused by a large duplication cyst but bowel position was normal at surgery. In the other one, jejunal position proved normal postnatally. due to T2 -weighted sequences high contrast resolution, fetal MRI is a useful tool for prenatal diagnosis of digestive malposition, including in cases where fetal ultrasound did not suspect this diagnosis.
Congenital diarrhea is very rare, and postnatal diagnosis is often made once the condition has caused potentially lethal fluid loss and electrolyte disorders. Prenatal detection is important to improve the immediate neonatal prognosis. We aimed to describe the prenatal ultrasound and magnetic resonance (MRI) imaging findings in fetuses with congenital diarrhea.The study reports the pre- and postnatal findings in four fetuses that presented with generalized bowel dilatation and polyhydramnios. We analyzed the fetal ultrasound and MRI examinations jointly, then compared our provisional diagnosis with the amniotic fluid biochemistry and subsequently with the neonatal stool characteristics.In each of the four cases an ultrasound examination between 22 and 30 weeks' gestation showed moderate generalized bowel dilatation and polyhydramnios suggesting intestinal obstruction. MRI examinations performed between 24 and 32 weeks' gestation confirmed that the dilatation was of gastrointestinal (GI) origin, with a signal indicating intraluminal water visible throughout the small bowel and colon. The expected hypersignal on T1-weighted sequences characteristic of physiological meconium was absent in the colon and rectum. This suggested that the meconium had been completely diluted and flushed out by the water content of the bowel. The constellation of MRI findings enabled a prenatal diagnosis of congenital diarrhea. The perinatal lab test findings revealed two cases of chloride diarrhea and two of sodium diarrhea.Congenital diarrhea may be misdiagnosed as intestinal obstruction on prenatal ultrasound but has characteristic findings on prenatal MRI enabling accurate diagnosis; this is important for optimal neonatal management.
