Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is probably normal in size . Although some areas of the right lung appear better aerated , there is overall new volume loss with moderate elevation of the right hemidiaphgram and rightward shift of mediastinal structures suggesting substantial atelectasis in the right lung . Atelectasis may be primarily perihilar noting that there is more coalescent opacity associated with the right hilum over the short interval A new area of right upper lateral subpleural opacification may be due to a loculated effusion but is not specific . The left lung appears clear .
    OUTPUT:
    
Substantial new volume loss in the right lung associated with increased perhilar opacity which may be associated with infection or post-obstructive pneumonitis .