Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac , mediastinal and hilar contours appear unchanged . Blunting of the left costophrenic sulcus suggests a small new effusion , with none identifiable on the right side . Streaky basilar opacity seen posteriorly are suggestive of minor atelectasis . Otherwise , lungs appear clear . There is no pneumothorax .
    OUTPUT:
    
Small pleural effusion on the left only .