Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Although a left anterior third rib fracture can be visualized , for the most part , known left - sided fractures are not well assessed . There is no pneumothorax or pleural effusion . Streaky opacities in the lower lungs suggest atelectasis in association with low lung volumes . The cardiac , mediastinal and hilar contours appear unchanged . A mild - to - moderate superior endplate compression fracture along an upper thoracic vertebral body appears unchanged . An L1 vertebral body compression fracture is not well assessed , but also appears unchanged .
    OUTPUT:
    
Low lung volumes with increasing bibasilar atelectasis , but no evidence for pneumothorax or pleural effusion . Rib fractures are not well assessed .