Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Ill - defined airspace opacity in the medial right lower lung may represent atelectasis related to low lung volumes . The upper lungs are mildly hyperinflated . There is no pleural effusion , pneumothorax , or pulmonary edema . The cardiomediastinal silhouette , including a tortuous descending aorta , is unchanged .
    OUTPUT:
    
Ill - defined right lower lung airspace opacity may represent atelectasis .