Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The tracheostomy is again noted . The overall appearance is quite similar , though slight differences are present on both sides . On the right , there is slight difference in distribution of right lung opacities . In particular , the previous seen dense platelike opacity in the right mid / lower zone is no longer visualized and may have resolved . The small right pleural effusion is similar in appearance . In the left lung , there is upper zone redistribution . Patchy retrocardiac opacity is slightly more pronounced with new partial obscuration left hemidiaphragm and suggested left lower lobe air bronchograms . On the left , mild upper zone redistribution and slight vascular plethora .
    OUTPUT:
    
Suspected very slight improvement in opacities in the right infrahilar region . Slight worsening of collapse / consolidation at the left lung base . On the left , mild upper zone redistribution and slight vascular plethora .