Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal , and the mediastinal and hilar contours are unremarkable . Lung volumes are reduced compared to the prior study . There is minimal ill - defined patchy opacities in both lung bases , findings which could reflect atelectasis , but infection is difficult to exclude . No focal consolidation , pleural effusion or pneumothorax is present . There are no acute osseous abnormalities .
    OUTPUT:
    
Patchy ill - defined opacities in both lung bases , findings which could reflect atelectasis but infection can not be excluded .