Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single AP view of the chest provided . Lung volumes are low , but grossly clear . Minimal retrocardiac scarring versus atelectasis is unchanged . No pleural effusion or pneumothorax . Hilar and cardiomediastinal contours are normal .
    OUTPUT:
    
Lung volumes are low , but there is no evidence of pneumonia or aspiration .