Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiac silhouette size remains mildly enlarged . The mediastinal and hilar contours are unchanged . Lung volumes are low causing crowding of bronchovascular structures with possible mild pulmonary vascular engorgement but without overt pulmonary edema . Patchy opacities in lung bases may reflect areas of atelectasis in the setting of low lung volumes . No pleural effusion or pneumothorax is clearly identified . There are no acute osseous abnormalities .
    OUTPUT:
    
Low lung volumes with patchy opacities in lung bases possibly reflecting atelectasis . Possible mild pulmonary vascular engorgement .