Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Pulmonary edema since ___ radiograph has improved . The mediastinum has an expected postop appearance . No pneumothorax is seen . Mild bibasilar atelectasis is seen . Mild cardiomegaly which is largely unchanged .
    OUTPUT:
    
Improved pulmonary edema as compared to radiograph dated ___