Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal upright and lateral chest radiographs demonstrate well - expanded lungs . The cardiomediastinal contour is normal . The heart is normal in size . Streaky opacities at the right lung base are improved compared to the prior examination and likely reflect atelectasis . Again seen is high - density material projecting over the lower right chest , unchanged compared to the prior study . There is no free air under the diaphragm and no pneumothorax .
    OUTPUT:
    
No evidence of free air under the diaphragm .