Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Again seen is the left - sided chest tube , similar in position . Also again seen is the left pleural effusion , overall similar to the prior study . Mild vascular plethora previously seen on left lung has improved . The right lung is grossly clear , allowing for minimal atelectasis at the right lung base . No pneumothorax detected .
    OUTPUT:
    
Essentially unchanged compared with 1 day earlier .