Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are lower compared to the previous exam which accentuates the size of the cardiac silhouette which is mildly enlarged . Mediastinal and hilar contours are unremarkable . Crowding of the bronchovascular structures is demonstrated without overt pulmonary edema . Patchy opacities are noted in the lung bases , potentially atelectasis but infection is not excluded . No pleural effusion or pneumothorax is present . No acute osseous abnormality is seen .
    OUTPUT:
    
Low lung volumes with patchy bibasilar airspace opacities , likely atelectasis . Infection can not be completely excluded .