Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes remain low with chronic interstitial opacities again noted along the periphery and lung bases with associated honeycombing and fibrosis . Patchy retrocardiac opacity likely reflects atelectasis , however it is hard to exclude slight worsening of interstitial lung disease compared to the previous radiograph . Cardiac and mediastinal contours are similar with the heart size appearing mildly enlarged . Pulmonary vasculature is not engorged . No pleural effusion or pneumothorax is clearly demonstrated . No acute osseous abnormalities seen .
    OUTPUT:
    
Chronic interstitial lung disease most likely reflective of usual interstitial pneumonia , better characterized on prior chest CT . Patchy retrocardiac opacity likely reflects atelectasis though it is difficult to exclude slight interval worsening of chronic interstitial lung abnormality .