Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size can not be assessed accurately because of blunting densities in the left lung base . Significant cardiac enlargement is unlikely . Thoracic aorta of unchanged appearance without local contour abnormalities . The pulmonary vasculature is not congested . There exist some linear densities in the left upper lobe area that appear to be unchanged and most likely represent scar formations . On the left base , a moderate amount of pleural effusion obliterates the entire diaphragmatic contour and blunts the left pleural sinus . This extends into the posterior pleural sinuses as seen on the lateral view . The amount of pleural density appears to be same in comparison with the previous study of ___ .
    OUTPUT:
    
Slightly improved inspiration , but left - sided linear pulmonary scars and pleural effusion remaining . No new pulmonary or cardiovascular abnormalities identified .