Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Posterior basilar opacity best seen on the lateral view may be due to atelectasis , aspiration , infection is not entirely excluded in the appropriate clinical setting . No large pleural effusion is seen . There is no pneumothorax . The cardiac silhouette is moderately enlarged . The aorta is calcified . A right - sided central venous catheter terminates at the proximal right atrium .
    OUTPUT:
    
Posterior basilar opacity best seen on the lateral view may be due to atelectasis , aspiration , infection is not entirely excluded in the appropriate clinical setting .