Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are well expanded and show a focus of opacification in the left lung along the paraspinal region , which could represent a loculated fluid collection from previous effusion or a small area of scarring . There is a small left effusion , which has decreased compared to the previous examination . The heart size is enlarged . The mediastinal and hilar contours are normal . The right lung is clear .
    OUTPUT:
    
Interval decrease in the size of a now small left pleural effusion . Focus of scarring in the left superior segment of the lower lobe .