MR of Fetal Abdomen and Pelvis

Congenital malformations of the abdomen, pelvis, and gastrointestinal tract are common. As various organs can be affected, accurate location and morphological characterization are important for accurate diagnosis. Ultrasonography (US) is the imaging method of choice for screening and for evaluating fetal abdominal and pelvic anomalies, and magnetic resonance (MR) has proven useful as a complementary noninvasive technique in the study of fetal morphology. Excellent tissue contrast, the characteristic appearance of bowel loops on T2- and T1-weighted sequences, and the negligible influence of maternal position and fetal movements make MR ideal for the evaluation of abdominal and gastrointestinal tract disorders. In this chapter we describe the normal appearance of fetal abdominal and pelvic structures on MR, discuss the most common anomalies involving these structures, and define the role of MR in the study of these anomalies.