Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Median sternotomy wires are present . There is a background interstitial abnormality . Opacity in the right upper lung zone peripherally , not changed from ___ . No definite evidence of pneumonia . Cardiomediastinal silhouette unchanged . There is no pneumothorax . Slight blunting of the left costophrenic angle possibly secondary to pleural scarring or a small effusion .
    OUTPUT:
    
Background interstitial abnormality without convincing evidence of pneumonia .