Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes remain low . There is mild enlargement of the cardiac silhouette . The mediastinal and hilar contours are unchanged . Pulmonary vasculature is not engorged . Increased interstitial markings with patchy opacities at the lung bases persist , most likely reflective of a combination of known chronic interstitial lung disease with atelectasis . No focal consolidation , pleural effusion or pneumothorax is present . There are mild to moderate multilevel degenerative changes demonstrated in the thoracic spine .
    OUTPUT:
    
Low lung volumes with chronic interstitial abnormality and likely superimposed atelectasis at the lung bases .