Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest demonstrate improvement in a left hydro pneumothorax , with air - fluid level in the left apex , following left upper lobectomy . The fluid component is increasing relative to the aerated component , as expected . There has been interval resolution of the small remaining amount of subcutaneous air . Appearance of the right lung is unchanged compared to the prior study .
    OUTPUT:
    
Improving left hydro pneumothorax following left upper lobectomy .