Correct!
1. Osteophyte
There is a tubular opacity that appears to be connecting to the hilum on the lateral view (Figure 2).
Figure 2. Frontal and lateral chest radiographs show that the left hilum is somewhat “dense” compared with the right hilum, caused by an abnormal opacity projecting over the spine (arrow) on the lateral view.
All the answer choices are potential possibilities; however the chest radiographic findings would be an unusual appearance for an osteophyte, especially as the patient does not have osteophyte formation elsewhere in the spine. Pneumonia is possible given the patient’s history of cough. A pulmonary AVM and a posterior mediastinal mass such as a peripheral nerve sheath tumor are possible. Note there is partial calcification of the left hemidiaphragm, consistent with asbestos-related pleural disease.
Contrast-enhanced thoracic CT (Figure 3) was performed for further evaluation of the chest radiographic findings.
Figure 3. Enhanced thoracic CT displayed in soft tissue windows.
Based on the thoracic CT appearance, what is the diagnosis? (Click on the correct answer to proceed to the fourth of five panels)