Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A tracheostomy tube is in appropriate position . In comparison to the most recent prior study , there is similar appearance of the opacified left lung base silhouetting the left heart border and left hemidiaphragm , compatible with chronic moderate left pleural effusion and associated left lower lobe atelectasis . Superimposed infection in the appropriate clinical context can not be excluded . Mild streaky opacification of the right lung base is compatible with atelectasis . The cardiac silhouette is incompletely evaluated , but remains moderately enlarged . The upper lung zones are relatively clear .
    OUTPUT:
    
Persistent left basilar opacification , likely a combination of moderate left pleural fluid and underlying atelectasis or consolidation .