Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest were compared to previous exam from ___ . There is slight increased opacity projecting over the spine on the lateral view , potentially localizing to the left on the frontal view . The frontal view is not significantly changed from prior . Elsewhere , the lungs are notable for stable linear opacity in the left mid lung with possible overlying pleural thickening . Cardiac silhouette is enlarged , but not significantly changed . Surgical clips are seen in the right upper quadrant suggesting prior cholecystectomy . Osseous and soft tissue structures are otherwise unremarkable .
    OUTPUT:
    
Increased opacity projecting over the spine on the lateral view , likely due to atelectasis . Please refer to subsequent CT chest .