Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Low lung volumes are again demonstrated . Chronic interstitial abnormality is again seen as well as more focal opacities within the left lung base , left perihilar region , and right upper lobe which are not significantly changed when compared to the prior exam . The cardiac , mediastinal and hilar contours are relatively unchanged with marked calcification of the aortic knob . No pneumothorax or large pleural effusion is demonstrated . The right PICC has been removed . Assessment of the pulmonary vascularity is limited .
    OUTPUT:
    
Relatively unchanged appearance of the chest compared to prior exam . Persistent opacities within the right upper lobe , left lung base and left perihilar region are redemonstrated on a background of chronic interstitial lung disease which on the prior chest CT was thought to reflect UIP or fibrosing NSIP . As before , these more focal opacities may reflect progression of chronic interstitial lung disease , acute exacerbation of interstitial lung disease , or possibly infection .