Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Low lung volumes account for mild bronchovascular crowding . An ill - defined opacity in the right lower lung region is identified . Elsewhere lungs are clear . Cardiomediastinal sillouette is within normal limits There is no pleural effusion or pneumothorax .
    OUTPUT:
    
Low lung volumes with right basilar opacity which is likely atelectasis .