Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is normal in size . The cardiomediastinal and hilar contours are within normal limits . There may be mild bronchial wall thickening . Bibasilar opacities persist however there is markedly improved aeration of the left lower lobe . There is no effusion or pneumothorax .
    OUTPUT:
    
Subtle bibasilar opacities likely reflect atelectasis , however there is markedly improved aeration of the left lower lobe from ___ .