Prenatal diagnosis of abdominal lymphatic malformations.

Abdominal lymphatic malformations (LM) are rare congenital malformations of the lymphatic system, representing only 2% of all LM in newborns. They may arise from intra-abdominal solid organs (such as the liver, pancreas, kidneys, spleen, adrenal glands, and gastrointestinal tract), mesentery, omentum, and retroperitoneum. Mesenteric LM are the most commonly seen, with retroperitoneal LM being the second most common. Fetal abdominal LM could be associated with karyotypic or other abnormalities, including skin edema, hydrops fetalis, and polyhydramnios, and prenatal diagnosis and perinatal counseling for these LM are important. Prenatal ultrasound (US) and magnetic resonance imaging (MRI) have led to an increased diagnosis of abdominal LM and improved monitoring and intervention postnatally. This article provides an overview of fetal abdominal LM, including the prenatal diagnoses, differential diagnoses, comprehensive illustrations of the imaging findings, treatments, and fetal outcomes.