Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral chest radiographs were obtained . There are subtle patchy opacities at the right lung base . The heart size top - normal and the mediastinal contours are stable . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
Subtle right lung base opacity which may be due to atelectasis , however infection is not excluded in the appropriate clinical setting .