Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single portable view of the chest demonstrates lower lung volumes on the current exam . Interstitial changes are seen compatible with patient 's known underlying COPD . Left base opacity , most suggestive of scarring , unchanged from priors . The cardiomediastinal silhouette is within normal limits for technique . Atherosclerotic calcifications seen at the aortic arch .
    OUTPUT:
    
No definite acute cardiopulmonary process .