ABSTRACT
Good quality thoracic radiographs can provide vital information about overall cardiac size and shape in dogs and cats with heart disease. Radiographs are the best means of evaluating pulmonary blood vessels, examining the lungs for evidence of edema or other abnormalities, and assessing the pleural space, mediastinum, and diaphragm. However, a major limitation of radiography is that fluid has the same opacity as soft tissue. Because the heart appears as a single fluid/tissue opacity, internal structures cannot be discerned and pericardial effusion cannot be differentiated from cardiomegaly.
