Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single AP view of the chest is provided . No pneumothoraces are seen . Lung volumes are low causing crowding of the bronchovascular structures . At the left lower lobe , there is an ill - defined opacity which could be consistent with an infectious process in the correct clinical setting , or aspiration . There is mild right basilar atelectasis . Cardiomediastinal silhouette and hilar contours are unremarkable .
    OUTPUT:
    
Ill defined left lower lobe opacity , possibly infection versus aspiration .