There are two surgical alternatives to NMD. Unlike NMD, they do not cause permanent damage to brain tissue (this means they can be reversed). These are:
Deep brain stimulation (DBS)
What is DBS?
DBS is a type of brain surgery. It has been used as a treatment for:
- severe depression that has not been helped by other treatments
- long-term OCD that has not been helped by other treatments
- movement disorders such as Parkinson's disease
The National Institute for Health and Care Excellence (NICE) has produced clinical guidelines for the use of DBS in Parkinson's disease, but not for depression or OCD. This is because there is a lack of evidence on how safe or effective DBS is at treating mental health problems.
How does DBS work?
If you have DBS, you will be given a local or a general anaesthetic. A stereotactic frame is used to implant electrodes (insulated wires that conduct electricity) in your brain, but, instead of destroying the cells, the electrodes are left in place and used to stimulate a small area of your brain.
Wires lead just under your skin from your brain to a stimulator (similar to a pacemaker), which is set in your chest wall, and is programmed to deliver electrical stimulation.
With both depression and OCD you might find DBS helpful while the stimulation is turned on, but your problems could return when it is turned off.
What are the side effects of DBS?
Possible side effects are:
- wound infection after the operation
- complications if the equipment goes wrong, such as problems with the stimulator
- complications as a result of the surgery such as bleeding in the brain and seizures
- an increase in symptoms of depression and anxiety
Some people have reported experiencing suicidal feelings after DBS but this is thought to be quite rare and it is not known whether it is caused by the surgery itself or the mental health problems that they are having treatment for.
Also, having the DBS implants means that you cannot be treated with electroconvulsive therapy (ECT).
Where is DBS performed?
DBS is performed in Southmead Hospital, Bristol, as well as the NMD centre in Dundee.
Vagus nerve stimulation (VNS)
What is VNS?
VNS is a type of brain surgery, used in rare cases to treat:
- severe depression that hasn’t been helped by other treatments
- epilepsy (a neurological disorder that can cause seizures)
There is some research that shows that VNS can help to reduce the symptoms of severe depression hasn’t been helped by other treatments.
However, VNS is not currently recommended by the National Institute for Health and Care Excellence (NICE) for the treatment of mental health problems because there is not enough research on its safety and how effective it is.
How does VNS work?
A device called a generator is implanted in your chest, with electrodes connected to the vagus nerve in your neck area. The device sends timed pulses to your vagus nerve, which has branches from many organs of your body to your brain. The procedure is carried out under general or local anaesthetic.
What are the side effects of VNS?
Possible side effects are:
- neck pain
- sore throat difficulties breathing
- changes in your voice
Reducing the intensity or the frequency of the electrical pulses from the generator implanted in your chest may help to reduce the side effects that you experience.
Where is VNS performed?
VNS is more widely available than DBS, but it is still only offered in specialist centres by experienced staff. As it's used most commonly to treat epilepsy, VNS may be more likely to be performed in centres where there is a specialist epilepsy clinic.