Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Indwelling support devices are stable in appropriate position . The right lung is clear . Near complete opacification of the left hemithorax with volume loss likely reflects substantial atelectasis . Aeration of left lung apex has not substantially changed . No visible pneumothorax . No definite deep sulcus sign . Large calcified mass in the right upper quadrant
    OUTPUT:
    
Near complete opacification of the left hemithorax with volume loss likely reflects substantial atelectasis has not substantially changed .