Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiomediastinal and hilar silhouettes are unremarkable . Mild streaky atelectasis at the bilateral lung bases . There is a rounded opacity seen at the posterior left chest base . This is most likely a small Bochdalek 's hernia and is best seen on the lateral view . However , focal consolidation is not excluded . If there is high concern , this could be further evaluated with CT scan . Multilevel moderate degenerative changes of the thoracic spine are present . No priors are available for comparison .
    OUTPUT:
    
There is a rounded opacity seen at the posterior left chest base . This is most likely a small Bochdalek 's hernia and is best seen on the lateral view . However , focal consolidation is not excluded . If there is high concern , this could be further evaluated with CT scan .