Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Left pleural drain has been pulled in slightly higher position . The lung volume is still low . The right lung base opacification is slightly improved . The left lung is still opacified at the base , might be atelectasis but pneumonia can not be excluded . Severe subcutaneous emphysema is stable . Pneumomediastinum is slightly increased , especially alongside the left upper lobe , where minimal increase of pneumothorax can not be excluded . Heart size is top normal . Aorta is mildly elongated with calcification in the aortic arch as for aortosclerosis .
    OUTPUT:
    
Stable subcutaneous emphysema , minimal increse of pneumomediastinum . Persistent bibasilar opacities , more prominent at the left base .