Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Since ___ , bilateral asymmetrically distributed perihilar and basilar opacities are mildly improved in the left lung , likely representing pulmonary edema although superimposed pneumonia can not be excluded in the right clinical setting . The tip of the endotracheal tube is seen 4 .0 cm above the carina . Unchanged positioning of the left PICC line . No pneumothorax .
    OUTPUT:
    
Mild improvement in bilateral asymmetrically distributed perihilar and basilar opacities since ___ .