Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A large right pleural effusion is present . There is associated right basilar opacification likely reflective of compressive atelectasis . Left lung is clear . No left - sided pleural effusion or pneumothorax is present . The pulmonary vascularity is not engorged . The mediastinal contours appear unremarkable where visualized . Heart size is difficult to assess , but is likely within normal limits . Probable cholecystectomy clips are seen in the upper abdomen on the lateral view . There are no acute osseous abnormalities .
    OUTPUT:
    
Large right pleural effusion with right basilar opacification likely reflective of compressive atelectasis . Infection can not be completely excluded .