Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart appears mildly enlarged . The lung volumes are low . Mitral annular calcifications are unchanged . The mediastinal and hilar contours appear unchanged . There is similar slight blunting at each costophrenic sulcus . Although these may reflect tiny pleural effusions , scarring may also explain the appearance . A mild background interstitial abnormality appears unchanged .
    OUTPUT:
    
No evidence of acute disease .