Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A left - sided chest tube is unchanged in position when compared to the prior study . No pneumothorax seen . An endobronchial valve is noted in the left hilar region with associated left upper lobe collapse . This results in the luftsichel sign around the aortic knob . No pleural effusion . No consolidation seen .
    OUTPUT:
    
No significant interval change when compared to the prior study .