Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Low lung volumes bilaterally with crowding of the vasculature in the lung bases . Bibasilar linear atelectasis is seen . Pleural surfaces are normal without pleural effusion or pneumothorax . The heart size is mild to moderately enlarged , however , is likely accentuated by patient positioning , low lung volumes , and AP technique . Mediastinal contour and hila are normal .
    OUTPUT:
    
1 . Low lung volumes . 2 . No evidence of pneumonia .