Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable AP upright chest radiograph was provided . The lungs appear clear aside from minimal plate - like left lower lung atelectasis . The heart and mediastinal contours appear normal . There is no pleural effusion or pneumothorax . Heart size is normal . Bony structures appear intact . There is no free air below the right hemidiaphragm .
    OUTPUT:
    
No acute intrathoracic process .