Umbilical venous catheterization (UVC) is a common procedure performed in neonatal intensive care units. Inadvertent extravasation of parenteral nutrition (PN) into the liver parenchyma causing a fluid collection defined as TPN-oma is a well-known complication due to malpositioned UVC. The paper reports the case of a preterm female infant born at 30 weeks gestational age with a hepatic lesion containing PN fluid, successfully treated with ultrasound-guided aspiration.