Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Persistent basilar predominant interstitial lung disease as evaluated on recent chest CT . No focal consolidation , effusion , edema , or pneumothorax . The heart remains mildly enlarged . Enlarged mediastinal lymph nodes on the recent chest CT are not as well appreciated on this radiograph . A hiatal hernia is small . No acute osseous abnormality . Multilevel degenerative changes in the thoracic spine are mild .
    OUTPUT:
    
Bibasilar interstitial lung disease has been more fully characterized by a recent CT . No definite superimposed secondary process such as pneumonia , although subtle new abnormalities may be difficult to detect in the setting of chronic lung disease .