Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A portable radiograph of the chest is provided . There are bilateral lower lobe opacities . The lungs are otherwise clear . The hilar and cardiomediastinal contours are normal . Lung volumes are very low . There is a double - lumen catheter terminating near the cavoatrial junction . There is no pneumothorax .
    OUTPUT:
    
Low lung volumes with lower lobe opacities , which may represent atelectasis , but should be correlated clinically to rule out an infectious process . See subsequent CT for further details .