Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is normal . The aorta is slightly unfolded . The mediastinal and hilar contours are unremarkable . On the lateral view , there is a 2 .2 cm rounded opacity projecting over the lower lobes and descending thoracic aorta , not clearly delineated on the frontal view . The remainder of the lungs are clear . No pleural effusion or pneumothorax is identified . There are mild degenerative changes in the thoracic spine . Mild scarring is noted within the lung apices .
    OUTPUT:
    
1 . Approximately 2 .2 cm rounded opacity projecting over the lower lobes on the lateral view in the region of the descending thoracic aorta . This could reflect a summation of shadows as no corresponding abnormality is definitively noted on the frontal view , but a non urgent chest CT is recommended for further evaluation . 2 . No acute cardiopulmonary abnormality otherwise seen .