Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is normal in size . The mediastinal and hilar contours appear within normal limits . There is probably a very small pleural effusion on the left but pleural effusions have mostly resolved . Moderate S - shaped curvature is noted along the visualized thoracolumbar spine .
    OUTPUT:
    
Small left - sided pleural effusion ; no evidence of pneumonia or parenchymal edema .