What can doctors see on a chest x-ray?

Many things: Cardiac enlargement reflecting heart disease. Abnormalities in ventilation of lungs. Increased densities which may mean edema(fluid in lungs), hemorrhage, tumor, infection and trauma. Skeletal abnormalities such as fractures, dysplasia, bone tumors. Enlarged lymph nodes in mediastinum representing tumor or infection. Congenital abnormalities are often noted of skeleton, lungs, or heart.