Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single upright view of the chest demonstrates large right pneumothorax , producing mild leftward deviation of the cardiomediastinal structures . Left lung is clear . Right lower lobe opacity , likely reflects compressive atelectasis .
    OUTPUT:
    
Large right pneumothorax , possibly tension . Findings discussed with Dr . ___ at 5 :45 a .m . at the time of discovery .