Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The patient is status post median sternotomy and CABG . The cardiac silhouette size is top normal , unchanged . The mediastinal and hilar contours are stable . Lung volumes are slightly decreased compared to the prior exam , causing mild crowding of the bronchovascular structures . No pulmonary edema is present . Minimal streaky opacities are seen within both lung bases , likely atelectasis . There is no focal consolidation , pleural effusion or pneumothorax . Old right - sided rib fracture is again noted . There are mild degenerative changes in the thoracic spine .
    OUTPUT:
    
Mild bibasilar atelectasis .