Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are low lung volumes . Streaky lower lung opacities bilaterally are compatible with chronic fibrosis . There is relative sparing of the left upper lobe . Heart size and mediastinal contours are within normal limits for a frontal projection . No pleural effusion .
    OUTPUT:
    
Chronic fibrotic changes and no definite evidence of pneumonia .