Recognition of Neonatal Lymphatic Flow Disorder: Fetal MR Findings and Postnatal MR Lymphangiogram Correlation

Abstract

This study aimed to describe prenatal and postnatal imaging features and outcomes of neonates with neonatal lymphatic disorders (NLDs). An institutional review board-approved search of the radiology database for patients with NLD identified five patients. Inclusion criteria include prenatal imaging (fetal magnetic resonance [MR] imaging and ultrasound) and postnatal three-dimensional T2 Sampling Perfection with Application optimized Contrasts using different flip angle Evolution (SPACE) and dynamic contrast-enhanced MR lymphangiography within 6 months of life. Chart review was undertaken to evaluate morbidity and mortality. Prenatal finding of "nutmeg lung" or fetal pulmonary lymphatic disorder was identified in all five patients on fetal MR imaging, and in four of five patients on fetal ultrasound. Postnatal dynamic contrast-enhanced MR lymphangiography demonstrated abnormal lymphatic flow to the lungs in four of five patients, but absent in the single patient with coexisting hypoplastic left heart syndrome (HLHS). Dermal backflow was seen in one patient, also the only patient with prenatal body wall edema. Three patients with lymphatic flow to the lungs only were classified as neonatal chylothorax. The patient with dermal backflow and perfusion to the lungs was diagnosed with central lymphatic flow disorder (CLFD). The HLHS patient with normal lymphatic perfusion maintained the HLHS diagnosis. Of the five patients, the patient with CLFD and the one with HLHS expired because of respiratory distress. NLDs can be recognized on prenatal and postnatal imaging and may be primary, as in neonatal chylothorax or CLFD, or secondary. In this small series, "nutmeg lung" was present in all patients. Prenatal imaging demonstrates that body wall edema may correlate with postnatal dermal backflow, which, in our small cohort, carried a poor prognosis.