Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared with the prior radiograph , increased bibasilar opacities reflect atelectasis . Heart size is top normal . Mediastinal and hilar silhouettes are normal . Lungs are otherwise clear without focal consolidation , pleural effusion , or pneumothorax . Linear calcifications overlying the right lung apex are unchanged . Healed bilateral rib fractures are unchanged in appearance . A left - sided presumed pacer device is unchanged in appearance and position .
    OUTPUT:
    
No evidence of pneumothorax .