Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable upright chest radiograph ___ at 23 :28 is submitted .
    OUTPUT:
    
There has been interval appearance of mild perihilar and interstitial edema . Overall cardiac and mediastinal contours are likely unchanged given differences in patient rotation . No large effusions . No pneumothorax . Improved aeration at the left base consistent with resolving atelectasis .