This page also covers a newer treatment, external trigeminal nerve stimulation.
Vagus nerve stimulation is a treatment option for children and young people with frequent seizures resistant to anti-seizure medication, and for whom epilepsy surgery is not an option.
What is the vagus nerve?
The vagus nerve is the longest and most complex of the 12 pairs of cranial nerves that start in the brain.
The vagus nerve sends information to or from the surface of the brain to tissues and other organs in the body.
What is vagus nerve stimulation?
In vagus nerve stimulation (VNS), a battery-powered, pulse-generator device, about the size of a cardiac pacemaker – the vagus nerve stimulator – is implanted under the skin of the upper left chest.
A wire is tunnelled under the skin and connected to the left vagus nerve in the neck. This takes between 45 minutes and two hours.
About two weeks after the device has been implanted, it will be switched on.
The device is programmed for pulse width and frequency, current intensity and on/off cycles with a programming wand.
The device is always on and set to send pluses every few seconds. Swiping the magnet over the generator device produces an additional pulse when seizures are just about to happen or are happening. You can turn it on and off at will.
The battery lasts 8–12 years and can be replaced under local anaesthetic.
Typical treatment might involve intermittent stimulation for 30 seconds every 5–10 minutes throughout the day and night.
Who is VNS suitable for?
VNS can be used in children and young people with epilepsy, particularly those who have focal onset seizures resistant to even the highest possible doses of anti-seizure medication, and for whom epilepsy surgery is not an option.
It has also been used for:
- Children with encephalopathic seizures (severe epilepsy with delayed development or even loss developmental skills) that are resistant to anti-seizure medication
- Idiopathic seizures (seizures with no known cause), including tonic-clonic seizures, childhood absence epilepsy, juvenile absence epilepsy and juvenile myoclonic epilepsy
- Lennox-Gastaut syndrome
VSN can be used as an add-on treatment to anti-seizure medications.
It has been used in children as young as six months old, but it is more commonly used in older children.
Before a child or young person has VNS, their epilepsy specialist should discuss with them, and their parents or carers, as appropriate, the risks and benefits of the procedure.
How long does VNS take to work?
It may take 6–12 months after the VNS device has been fitted before you see any improvement in seizure control, with the full effect taking up to 18 months.
What are the side effects of VNS?
VSN is considered to be a safe procedure with no major complications. Typical side effects can include:
- Hoarseness
- Throat discomfort
- Occasional coughing and swallowing difficulties that often settle over time
Side effects are usually mild and can generally be resolved by adjusting the settings to reduce the current.
The procedure can also alter children’s voices. More serious, but rarer, side effects include:
- Infection when the device is being removed
- Irregular breathing
