Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest are compared to previous exam from ___ . There is a rounded opacity in the left mid lung , which is not clearly visualized on the lateral , but may project over the spine . The lungs are otherwise clear . There is no effusion or pulmonary vascular congestion . The cardiac silhouette is slightly enlarged but unchanged . No acute osseous abnormality is detected .
    OUTPUT:
    
Nodular opacity projecting over the left lower lung , potentially within the lower lobe . Nonurgent chest CT suggested to further characterize .