Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is top normal to mildly enlarged . The mediastinal contours are not widened . Retrocardiac opacity obscuring the medial left hemidiaphragm with also areas of relative retrocardiac lucency may be from previously seen hiatal hernia . The sternotomy wires are unchanged . The lungs show improved but continued bibasilar and right upper lung airspace opacities . There is no pneumothorax .
    OUTPUT:
    
Improved but persistent multifocal opacities likely representing multifocal pneumonia - recommend follow - up imaging after treatment to ensure resolution . Hiatal hernia .