Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is normal in size . The aorta is mildly tortuous and calcified . The mediastinal and hilar contours appear unchanged , allowing for differences in technique . The lateral view shows slight patchy posterior left basilar opacity that can probably be attributed to atelectasis , which has improved since the prior CT from ___ .
    OUTPUT:
    
No evidence of acute disease .