Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The right hemidiaphragm remains elevated with overlying atelectasis . Left base atelectasis is seen , likely similar to prior , underlying infection or aspiration not entirely excluded . No pleural effusion or pneumothorax is seen . The cardiac and mediastinal silhouettes are stable .
    OUTPUT:
    
Left base atelectasis is seen , likely similar to prior , underlying infection or aspiration not entirely excluded .