CT scans detect disease or injury within different parts of the body. CT has become a valuable screening tool to identify potential tumors or abdominal lesions. Also, CT scans can be used to image the head to locate injuries, tumors, clots that lead to stroke, hemorrhage and other conditions. CT scans will image the lungs to show cancers, pulmonary embolism (blood clots), excess fluid and other conditions such as emphysema or pneumonia. While imaging complex bone fractures, badly damaged joints or bone tumors, a CT scan is particularly useful.