Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is an opacity at the right lung base abutting the right heart border , which could represent pneumonia in the appropriate clinical setting . This is best appreciated on the frontal view , with no definite correlate on the lateral view . There is no pleural effusion or pneumothorax . Heart size is top - normal . No acute osseous abnormalities identified .
    OUTPUT:
    
Right middle lobe opacity , possibly representing pneumonia in the appropriate clinical setting .