Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest were obtained . There is persistent chronic , diffuse , mild increase in interstitial markings bilaterally , similar to prior dating back to at least ___ . Bibasilar atelectasis is seen without definite focal consolidation . No pleural effusion or pneumothorax is seen . The cardiac and mediastinal silhouettes are stable .
    OUTPUT:
    
Chronic , diffuse increase in interstitial markings . Slight increase in opacity at the right lung base is felt to more likely be due to atelectasis rather than consolidation .