Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest were obtained . The previously seen right hilar and right upper lobe opacity is again seen and is consistent with mass seen on recent CT scan . Elevation of the right lung base with associated volume loss in the upper lobe is also unchanged since prior study . There is also some post-obstructive changes in the right upper lobe , which appear less prominent than on prior study . The mediastinal width is unchanged compared to prior radiograph . There is no evidence of pulmonary edema or pneumothorax .
    OUTPUT:
    
Interval improvement in previously seen post-obstructive changes and improved aeration of the right lung . Otherwise , unchanged since the prior study .