Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared with prior radiographs on ___ , there is a large convex mediastinal opacity centered at the aortic - pulmonary window , possibly representing a postop mediastinal hematoma or medial loculated fluid collection . Pulmonary edema , bibasilar consolidations , and moderate left and small right pleural effusions have improved . Median sternotomy wires and right axillary clips are stable in appearance .
    OUTPUT:
    
1 . Large convexity of left mediastinal border adjacent to the aortic knob , which may represent a postoperative mediastinal hematoma or medial loculated pleural fluid collection . This could be more fully characterized by CT if warranted clinically . 2 . Interval slight improvement in pulmonary edema , bibasilar consolidations , and moderate left and small right pleural effusions .