Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are chronically hyperinflated with biapical scarring . There is improvement in the left lower lobe opacification without complete resolution . The mediastinal contours , cardiac borders , and lungs are otherwise unchanged .
    OUTPUT:
    
Improved but not resolved left lower lobe pneumonia . Follow - up radiograph in 4 weeks is recommended to ensure resolution .