Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Patient is status post median sternotomy . Postsurgical changes are again noted at the left hemi thorax with left mid lung scarring and left base retrocardiac opacity . There is also right perihilar and infrahilar opacity , similar in distribution compared to the prior CT from ___ although may be slightly increased , could be due to radiation pneumonitis and superimposed postprocedural change although overlying infection is not excluded . No pneumothorax is seen . The cardiac and mediastinal silhouettes are stable .
    OUTPUT:
    
Patient is status post median sternotomy . Postsurgical changes are again noted at the left hemi thorax with left mid lung scarring and left base retrocardiac opacity . There is also right perihilar and infrahilar opacity , similar in distribution compared to the prior CT from ___ although may be slightly increased , could be due to radiation pneumonitis and superimposed postprocedural change although overlying infection is not excluded . No pneumothorax is seen . The cardiac and mediastinal silhouettes are stable .