Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest are provided . There is a left chest tube in unchanged position with the tip positioned near the left lung apex . There is increased left basilar opacity which likely represents left pleural effusion . There is no discernable pneumothorax on the left . The right lung remains clear . Overall , cardiomediastinal silhouette appears grossly stable , though the left heart border is somewhat effaced . Bony structures appear intact .
    OUTPUT:
    
Unchanged position of left chest tube with increasing left basal opacity likely representing effusion and probably a component of atelectasis . No definite pneumothorax is seen .