Coloured 3D computed tomography (CT) scan of the head and neck of a patient with nasogastric (NG) and endotracheal (ET) tubes inserted. NG tubes are fed through the nose, past the back of the throat and into the stomach for the direct administration of food and medicine. ET tubes are fed through the mouth and into the trachea (airways) to assist with breathing. These tubes may be needed for several reasons, such as when a patient is comatose, undergoing surgery, or has difficulty swallowing or breathing for any reason.