Neonatal lymphatic flow disorders: impact of lymphatic imaging and interventions on outcomes.

Neonatal chylothorax (NCTx) and central lymphatic flow disorder (CLFD) are historically challenging neonatal disorders with high morbidity and mortality. We conducted a retrospective study of 35 neonates with pulmonary lymphatic abnormalities at our institution who underwent lymphatic evaluation between December 2015 and September 2018. Patients with only pulmonary lymphatic perfusion syndrome were classified as NCTx and those with multiple flow abnormalities were classified as CLFD. Demographics, clinical characteristics, and outcomes were compared using t-tests/Wilcoxon rank sum tests and Fisher's exact tests. All 35 patients had intranodal MR lymphangiography and 14 (40%) also had conventional fluoroscopic lymphangiography. Fifteen (42.8%) patients were diagnosed with NCTx and 20 (57.1%) were diagnosed with CLFD. Thirty-four (97.1%) patients had pleural effusions. None of the NCTx group had ascites, anasarca, or dermal backflow compared to 17 (85%) (p < 0.001), 8 (42.1%) (p: 0.004), and 20 (100%) (p < 0.001) of the CLFD group, respectively. In the NCTx group, 11 (73.3%) had ethiodized oil embolization and 4 (26.7%) received conservative therapy. Ten (50%) of the CLFD patients had an intervention; of those, two (10%) had ethiodized oil-only embolization. Eight had non-ethiodized oil embolizations (two (25%) had embolization with glue, three (37.5%) underwent surgical lymphovenous anastomosis, two (25%) underwent thoracic duct (TD) externalization, and one (12.5%) had a non-TD lymphatic channel drain placed). Complete resolution of pleural effusions was achieved in all 15 NCTx patients, whereas 9 (45%) of 20 CLFD patients had resolution of chylothorax (p: 0.001). Establishing a diagnosis of NCTx or CLFD is paramount in selecting treatment options and providing prognostic information. Development of lymphatic interventions represents a paradigm shift in our understanding of neonatal lymphatic flow disorders and may be associated with improved survival.