Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lung volumes are low . The heart is normal in size . The mediastinal and hilar contours appear unchanged . There is no pleural effusion or pneumothorax . There is a persistent opacity in the left mid lung , as well as a posterior basilar component which is probably in the left lower lobe . Elsewhere , the lungs appear clear . Bony structures are unremarkable .
    OUTPUT:
    
Persistent patchy left lower lung opacities , although improved in the posterior basilar component . Pneumonia could be considered for this appearance in the appropriate clinical setting but there has been some improvement in opacification .