Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest were obtained . The heart is of top normal size , exaggerated by low lung volumes . Cardiomediastinal contours are stable . Lungs are clear without focal or diffuse abnormality . Vague retrocardiac opacity may represent atelectasis or infection . Blunting of the left costophrenic angle is compatible with a small effusion . No pneumothorax . No radiopaque foreign body .
    OUTPUT:
    
Small left pleural effusion with vague retrocardiac opacity , which may represent atelectasis or , in the right clinical setting , infection . Findings were communicated by ___ to Dr . ___ on ___ at ___ pm .