Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is normal in size . The mediastinal and hilar contours appear within normal limits aside from patchy calcification along the aortic arch . There is minimal subpleural scarring at the left lung apex . A mild interstitial process suggests congestion . There are no pleural effusions or pneumothorax . Small - to - moderate anterior osteophytes are present along the mid to lower thoracic spine . A healed old left sixth rib fracture is present .
    OUTPUT:
    
Mild interstitial abnormality , probably due to slight fluid overload or vascular congestion .