Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable AP upright chest radiograph obtained . The lungs are clear bilaterally . No pneumothorax or signs of pneumomediastinum . Heart and cardiomediastinal contour is normal . Bony structures are intact . No free air below the right hemidiaphragm .
    OUTPUT:
    
No acute intrathoracic process .