Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright portable chest radiograph was provided . Lungs appear hyperinflated with upper lobe lucency suggesting underlying emphysema . There is mild but stable linear opacity in the lower lungs , likely representing atelectasis or scarring . The left CP angle is excluded . Cardiomediastinal silhouette is stable . Bony structures are intact .
    OUTPUT:
    
Findings compatible with emphysema without superimposed acute intrathoracic process .