Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are underinflated with streaky opacities suggestive of atelectasis at the bases , slightly more confluent in the right lower lobe posterior . Cardiomediastinal silhouette is enlarged . There is no pleural effusion or pneumothorax . There is mild rightward curvature of the thoracic spine . Partially calcified aortic knob is again noted . Elevation of the right hemidiaphragm is a chronic finding .
    OUTPUT:
    
Low lung volumes with bibasilar atelectasis . No definite pneumonia , but short - term followup radiographs may be helpful to exclude focal aspiration or subtle pneumonia in right lower lobe posteriorly . Chronic elevation right hemidiaphragm .