Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is stable top - normal heart size with normal mediastinal and hilar contours . There is mild prominence of the interstitial markings which appears similar to prior . No focal consolidation , pleural effusion or pneumothorax . Midline sternotomy wires are intact .
    OUTPUT:
    
Mild interstitial abnormality , chronic .