Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Linear atelectasis is scarring in the lingula is improved when compared to the prior study . Lung volumes are within normal limits . The trachea is central . The cardiomediastinal contour is unchanged . The heart is not enlarged . No pleural effusion seen on the AP projection however there is likely a small effusion on the left side seen on the lateral projection only . No consolidation or pneumothorax seen . The visualized bony structures are unremarkable in appearance .
    OUTPUT:
    
Probable small left pleural effusion .