Radiographic and computed tomographic findings of intrathoracic ectopic liver in a dog

A 5-year-old spayed female Maltese was referred due to a suspected diaphragmatic hernia. Radiography revealed a soft tissue mass in the right caudal thorax with loss of diaphragm cupola dome-shape. A diaphragmatic hernia was considered, but surgical exploration revealed an intact diaphragm and unremarkable liver lobes. CT after a surgical inspection showed all intact liver lobes and intrathoracic mass connected to the liver. The intrathoracic mass was retracted to the abdomen by incising the diaphragm. Histopathologic examination revealed hepatocellular vacuolar degeneration, indicating an intrathoracic ectopic liver. Intrathoracic ectopic liver should be included in the differential diagnosis when diaphragmatic hernia is suspected in radiography.