Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The right chest tube appears unchanged in comparison to the prior chest radiograph . There is small amount of subcutaneous emphysema . No pneumothorax . There is bilateral apical pleural thickening , worse on the right . There is bilateral diffuse interstitial thickening , worse at the bases which is unchanged . Heart size is normal . The mediastinal and hilar contours are normal . The pulmonary vasculature is normal . No pleural effusion is seen . There are no acute osseous abnormalities .
    OUTPUT:
    
1 . Chest tube in appropriate positioning without evidence of pneumothorax . 2 . Unchanged bilateral diffuse interstitial thickening representing chronic interstitial lung disease .