Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single AP upright portable chest radiograph obtained . The lungs are clear . Cardiomediastinal silhouette is stable with prominence of the superior mediastinum which is attributable to tortuous mediastinal vessels as seen on prior MR ___ and stable from prior chest radiographs dating back to ___ . Bony structures are intact .
    OUTPUT:
    
No acute findings in the chest .