Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: In comparison to the prior chest radiograph from yesterday morning , the right - sided chest tube has been removed . There is now a 2 .2 cm air collection in the right apex , which is new since the chest tube has been removed . There is also expected volume loss as suggested by the tenting of the right hemidiaphragm . No other significant interval changes . Left lung is essentially clear .
    OUTPUT:
    
Interval development of a 2 .2 cm air collection in the right apex , new since the chest tube was removed . Recommend close interval followup to ensure stability .