This necropsy image shows a peritoneopericardial hernia with the liver in the pericardial sac. In small animals, most peritoneopericardial hernias are congenital, whereas most diaphragmatic hernias are traumatic. Clinical signs depend on which viscera are herniated within the thoracic cavity and the chronicity. Clinical signs of congenital peritoneopericardial can be associated with poor venous return to the heart, or respiratory or GI signs. However, most often this type of hernia is an incidental finding. Dx: Plain or contrast thoracic radiographs. Click here to see a lateral radiograph of a diaphragmatic hernia in a small animal. Rx: Surgical repair. Ref: Cohn and Cote, Clinical Vet Advisor – Dogs and Cats, 4th ed. pp. 778-89. Image courtesy of Kalumet.