Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . Known severe emphysema is better seen on chest CT . Streaky opacity in the right lower lung is likely atelectasis . Interstitial abnormality most prominent at the left base likely reflects combination of atelectasis and emphysema . There is no definite evidence of pneumonia . Mild cardiomegaly is unchanged . There is chronic elevation of the right hemidiaphragm . There is no pneumothorax .
    OUTPUT:
    
Bibasilar atelectasis and severe emphysema better depicted on prior chest CT . There is no definite evidence of pneumonia . Mild cardiomegaly is stable .