Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest demonstrate low lung volumes . There is small right pleural effusion . Right hemidiaphragm is slightly elevated . Right lung opacities may represent atelectasis . There is no left pleural effusion . Opacities in the left mid lung zone are slightly more conspicuous since prior . Mild perihilar vascular congestion . Otherwise , hilar and mediastinal silhouettes are unremarkable . Heart size is top normal . Partially imaged upper abdomen is unremarkable .
    OUTPUT:
    
Small right pleural effusion is unchanged since ___ exam . No left pleural effusion . Left mid lung zone opacities , slightly more conspicuous since prior , which may represent developing infection , atelectasis or aspiration .