Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are normally expanded . Opacities projecting over the spine on the lateral radiograph have improved ; however , there is mild persistent opacity . There is no pleural effusion or pneumothorax . Mild cardiomegaly is unchanged . The mediastinal and hilar contours are normal . The included osseous structures are grossly unremarkable .
    OUTPUT:
    
Improved mild residual opacity at the left base may reflect resolving pneumonia .