Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is persistent complete opacification of the left hemithorax with marked volume loss including leftward mediastinal shift . Streaky right upper lobe opacity has decreased , suggesting an atelectasis . Otherwise , the right lung appears clear . There is no right - sided pleural effusion . No pneumothorax is demonstrated . The patient is status post posterior lumbar fusion , incompletely characterized .
    OUTPUT:
    
No evidence of acute disease .