Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest were obtained . There is a subtle patchy right base opacity which could be due to atelectasis , although underlying infection is not excluded in the appropriate clinical setting . No pleural effusion is seen . There is no pneumothorax . The cardiac , mediastinal , and hilar contours are stable .
    OUTPUT:
    
Subtle patchy right base opacity could be due to atelectasis ; however , underlying infection in the appropriate clinical setting is not excluded .