Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiac silhouette size is normal . The mediastinal and hilar contours are unremarkable . Patchy opacities are demonstrated in the lung bases , findings which may reflect atelectasis , but infection or aspiration are not excluded in the correct clinical setting . No pleural effusion or pneumothorax is present . No acute osseous abnormality is visualized .
    OUTPUT:
    
Patchy bibasilar airspace opacities may reflect atelectasis however infection or aspiration are not excluded .