Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared to prior examination , the left - sided pleural effusion has significantly improved status post thoracentesis with small remaining amount of fluid with associated left base atelectasis . Atelectasis is also noted in the right lung base . Lung volumes are low . Edema has significantly improved . There is no pneumothorax .
    OUTPUT:
    
Significant improvement of left - sided effusion as well as of mild pulmonary edema with remnant low lung volumes and bibasilar atelectasis .