Deep Brain Stimulation (DBS) for Laryngeal Dystonia (also known as Spasmodic Dysphonia)

Deep brain stimulation (DBS) is the placement of electrodes on one side or both sides of the brain. The electrodes are connected to an extension cable, which is surgically tunnelled under the skin to connect to a neuropacemaker battery also implanted in a pocket under the skin in the chest or other suitable areas of the body (for example, lower abdominal area). 

Laryngeal dystonia is caused by abnormal activity in the brain which causes the voice box muscles to go into spasm when patients speak. This unwanted voice box muscle spasm causes the voice/speech problem. 

DBS delivers a high frequency electrical current in the area of the brain called the thalamus. High frequency electrical stimulation modulates misbehaving neuronal activity which is causing the muscles of the voice box to spasm on speaking. 

DBS therefore does not ‘cure’ the disorder but is aimed to help control the symptoms by masking the misbehaving neuronal activity. 

DBS is an established treatment for generalised and focal dystonia. It is currently a standard of care for treatment refractory movement disorders such as Parkinson’s disease, tremor, and dystonia. Laryngeal dystonia is a form of focal dystonia. The treatment of patients solely for their laryngeal dystonia is new at our Trust.

Patients are admitted to the hospital 2 days prior to surgery.  During this time, detailed brain MR scans, voice recordings, and preoperative assessments are performed. This can also be done on an outpatient basis for those living close to the hospital and can be discussed with the team. The hospital stay is between 4-5 days. Patients are advised to bring their own medications when they come to the hospital. 

As soon as the patient feels well and stable, he/she can be discharged home. After 2 to 4 weeks, patients will be invited to the Functional Unit for their first programming session, and the DBS system will be turned on.  

It could take 2 to 6 months to achieve the right balance of DBS settings to improve symptoms. Hence, patients are required to attend regular follow up at the hospital with the DBS nurses and neurosurgeons, whereby the DBS setting is fine-tuned.

DBS is performed in one sitting (i.e. the electrodes and neuro-pacemaker battery are implanted in one procedure) and the electrode placement can either be performed with the patient awake or asleep. The neurosurgeon and the DBS team will discuss this with the patient in advance. 

The surgery is not painful. For thalamic DBS, surgery is usually performed awake. A special frame is attached to the head using special pins. Local anaesthetic will be used to numb the skin before the pins are inserted. An MRI scan is then performed so that the surgical brain targets can be seen.  

The hair will not be shaved. However, to reduce the risk of infection, the hair will be washed with antiseptics. Antibiotics are given intravenously before the procedure starts. Through a small skin incision, two small holes are drilled in the skull at the top and to both sides of the head, behind the hairline if possible. A 1.5 mm thick probe is then introduced into the target area of the brain. Since the brain has no nerve endings, this is completely painless. You will be asked to repeat specific sentences during the surgery with and without electrical stimulation so that we can assess your voice. The permanent DBS electrode is then implanted and secured to the burr hole with a special burr hole cap. Then, the same procedure is repeated on the other side of the brain.

When the electrodes are in place, you will be given a general anaesthetic (put to sleep). Then a neuropacemaker is implanted under the collar bone and connected to the brain electrodes via wires hidden under the skin. The skin is closed so that all the hardware is covered. While you are still asleep, a CT scan is performed to show us the final position of the electrodes.  

The surgical procedure takes 2–3 hours. 

Programming of the stimulator will start 2–4 weeks after surgery in the outpatient clinic. This will begin by screening the electrodes for efficacy and side-effects. This process will take around 30 minutes to 1 hour.

• Significant cognitive (thought process) decline (i.e. short-term memory) 
• Swallowing problems – these will require assessment by the speech therapist 
• Significant brain structural changes according to MRI 
• Severe depression 
• History of falls and balance problem 
• Other relevant psychiatric conditions 
• Suicidal ideation 

Other medical conditions are not necessarily a contraindication but may increase further risk from surgery, such as heart problems, kidney problems, problems with breathing, prolonged bleeding problems, patients on blood thinning medication.

All treatments and procedures have risks, and the DBS team will talk to you about the risks of DBS in detail during your consultation. 

Complications from DBS surgery are very rare in well-established and experienced centres. Although complications are rarely observed, these complications may result in serious disability. However, less severe complications are reversible and easy to treat, and do not cause long-term and serious disability. 

Problems that may happen straight away

There is a very rare chance of bleeding in the brain during the surgery which may result in serious complications such as stroke, paralysis or death. These severe complications are rare and as yet never seen in our centre; nevertheless, these are serious complications that patients should know about. The risk of bleeding that may result to serious disability is less than 1% (i.e. less than 1 in 100 patients). 

Seizures can also happen in less than 1% of patients (i.e. less than 1 in 100 patients). This can happen immediately after DBS surgery, however, patients do not develop long-term epilepsy after surgery. 

Less common immediate complications are misplaced electrodes, which is less than 1% chance (i.e. less than 1 in 100 patients). 

In the exceedingly rare event of electrode(s) misplacement, immediate readjustment is carried out whilst the patient is still in the operating room. 

Bruising at the surgical site can happen, but this is usually of no long term consequence. 

Problems that may happen after surgery

Infection may occur after surgery. This may only become apparent several days or weeks after the surgery and usually starts with redness, swelling, oozing, or increasing soreness in the area where the battery is implanted, on the surgical head wounds, or along the implanted wires. Keeping your surgical wounds clean and dry is important. Less than 2 patients out of 100 develop an infection. 

Wound care advice: 

• Before surgery, all patients are swabbed for Methicillin resistant staphylococcus aureus (MRSA). All patients are advised to strictly follow an antibiotic treatment regime for 5 days prior to surgery. 
• After surgery, patients are advised to avoid touching the wound area. 
• Regular hand washing is important. 
• Always keep the wound area clean and dry. 
• While in hospital the wound dressing will be checked daily and will be replaced every 3 days. Patients will receive clear instruction on further wound care after discharge. 
• Patients are advised not to wash the hair until the stitches are taken out. 
• Stitches are taken out 10 days after the surgery. 

Problems that may happen in the longer term 

The side effects are usually a direct result of the stimulation; most are reversible by adjusting the DBS settings, but some are not as easy to resolve. 

• Different speech problems – usually a result of overstimulation. 
• Balance problem – this could be a result of overstimulation. 
• Dystonia (muscle contraction) – usually a result of overstimulation 
• Sensory symptoms (buzzing, tingling sensation) – usually a result of overstimulation.
• Double vision – usually a result of overstimulation or when a specific area in the brain that is responsible for eye movement is activated by the stimulation, this is reversible.
• Dyskinesia (excessive involuntary movement) – usually a result of overstimulation 
• Weight gain – a small number of patients may gain weight after surgery. The cause is unclear.
• Involuntary eyelid closing and eye disturbances – about 10 out of 100 patients may experience this side effect. This is reversible.
• Suicidal ideation – this is very rare, but if there are any current concerns and concerns in the past, patients are referred to a psychiatrist to assess the risk before the surgery.

Patients are advised to report side effects during the consultation. If you have any concerns, please contact our DBS nurses (contact details are provided at the end of this page).

If you decide not to have DBS, you will be referred back to the referring ENT consultant to discuss other alternative treatments.

The decision to offer DBS depends on the balance of the risk and benefit of the intervention. If DBS is not suitable for you, then you will be referred back to the referring ENT consultant to discuss other alternative treatments.

At present, there is no cure for laryngeal dystonia. There are three alternative options to DBS:

1. Speech and Language Therapy

Speech and Language therapy aims to help encourage more relaxed and efficient use of your voice when speaking with this condition.  

2. Injection of Botulinum Toxin to the muscles of the voice box

Injection of Botulinum Toxin (‘Botox’) to the muscles of the voice box is the current ‘gold standard’ of treatment for laryngeal dystonia. It aims to weaken the muscles of the voice box to reduce the voice box spasm that occurs on speech in laryngeal dystonia. 

The procedure involves Botox injection with a needle through the neck in clinic under local anaesthesia with a guidance from a specialist machine called an EMG machine that allows the doctor to help locate the position of the voice box muscle. Sometimes a scope (specialist camera) through the nose to directly visualise the voice box may also be used to help locate the position of the voice box muscles during injection. 

Around 90% of patients (i.e. 9 in 10 patients) are helped by Botox injection with good symptom improvement. Complication profile is significantly less (infection, bruising at the injection site, and swallow problem) than the DBS therapy being a significantly less invasive procedure. 

The main disadvantage of the Botox injection is that its therapeutic effect is only temporary lasting for 3–5 months on average. Therefore, patients will usually need a lifelong repeat injection every 4–6 months. Furthermore, there is a risk of patients developing resistance to Botox overtime from a repeated injection. Should this happen, the Botox treatment will stop working. 

We would expect all patients to have trialled Botox injections as it is a less invasive treatment as compared to DBS. We also encourage all patients to have speech and language therapy before considering DBS, and this should be continued after DBS surgery. 

3. Voice box surgery

Certain forms of voice box surgery have been performed for the adductor type of laryngeal dystonia. 

Myectomy or Myoneurectomy

This surgery involves either cutting the muscles that move the vocal cords on their own (myectomy), or cutting both the nerves and the muscles that move the vocal cords together (myoeneurectomy), to help reduce the strain and the voice box spasm that occurs during speech. There is very limited literature from doctors in the UK but foreign peer-reviewed outcomes of patients are available and said to be effective in 1 to 2 patients out of 3 patients (33–67% success rate). Long-term outcome data of this surgery is currently not available. Risks of this surgery include failure, risk of general anaesthetics, bleeding, infection, dental damage, and the scarring of the vocal cords, causing harsh or weak voice quality. 

Type 2 thyroplasty

This surgery involves remodelling the voice box framework using a titanium implant to help reduce the strain and, therefore, improve your voice in laryngeal dystonia. This surgery is only performed in Japan as the titanium implant used for the surgery is currently only licenced to be used in Japan.  

Please discuss these options with your ENT consultant. 

You will be contacted by the DBS coordinator as soon as you are allocated a date for your surgery. The waiting list for DBS surgery is currently around 3–4 months. It is important for patients to think about the implications of having a life-long treatment that will also require a life-long commitment to attend outpatient follow-up and to regularly communicate with the DBS team. 

Approximately six weeks before the surgery, you will be seen in the pre-surgery assessment clinic. This involves blood tests, swabs for MRSA, and other tests as appropriate. All patients are required to complete an eradication therapy for MRSA prior to surgery. This will be discussed with the patient during the pre-assessment appointment prior to surgery. 

IMPORTANT: It is essential that patients’ medications containing aspirin or non-steroidal anti-inflammatory drugs (NSAID), e.g. Ibuprofen (Nurofen), Naproxen, Diclofenac (Voltarol) etc., are stopped two weeks before and until two weeks after surgery. This is mandatory to maximally avoid the risk of bleeding in the brain during surgery. If pain relief is necessary, Paracetamol is safe to use, as well as Co-codamol. Please discuss with the DBS nurses if you take any of those medications and if you take contraceptives or homeopathic over-the-counter medications. 

If you are taking blood-thinning medications or anticoagulation drugs for heart disease or bleeding problems, you will need to be referred to your responsible doctors to get advice on how to stop the blood-thinning medications and the risks involved in stopping medications temporarily. 

Please do not hesitate to contact the DBS team if you have any questions or concerns.

Patients will be given a follow-up appointment 1–2 weeks after hospital discharge to see the DBS nurses for wound review and removal of stitches. For patients living far away, the removal of stitches can be performed by their local GP. A first appointment to start the stimulation will be booked about 2–4 weeks after the surgery. Patients can contact the DBS nurses for advice via telephone and email consultation or to arrange follow up in clinic. 

For urgent consultations or concerns please contact the DBS coordinator and secretaries, who will inform your DBS nurse or doctor. The DBS team will address the concern on the phone or arrange physical review if needed. 

During weekends or bank holidays, patients can contact the UCLH switchboard and request to speak to the on-call doctor at the National Hospital for Neurology and Neurosurgery. The on-call doctors will do their best to ensure patients are safe and not in too much distress. If necessary, they will arrange for the patient to come to the hospital. In the event of an emergency a patient should always attend their nearest A and E to ensure they are assessed and treated promptly.

It is important to note the following: 

• DBS treatment requires a lifetime commitment to follow up visits to the hospital for review and assessment. 
• Exercise and physical activity can be resumed a few weeks after surgery. 
• Sauna, steam room and sunbeds are not recommended. 
• Scuba diving is only allowed up to a depth of 33 feet / 10m. 
• Extreme/Contact sports can risk breaking or damaging the DBS hardware. 
• You can normally resume work within 4-6 weeks after surgery. 
• Travelling – always carry an identification card for the DBS. Do not go through airport metal detectors. If you need to travel in an airplane within the first months after surgery, please get advice from the DBS team. 
• Do not stand near theft detectors and any object with a strong magnetic field. 
• Patients will require regular battery checks and battery replacement (usually every 3-5 years for non-rechargeable DBS and 10-20 years for rechargeable DBS). 
• Patients will be given a personal controller to enable them to carry out battery. checks and limited adjustments of DBS settings. 
• Patients should inform the DBS team if they require surgical, dental or investigative procedures to check hardware compatibility. 
• Specific medical equipment that is contraindicated for use in patients with DBS include the following: 
  • monopolar electrocautery 
  • diathermy 
  • bone growth stimulator 
  • lithotripsy 
  • arc welding.
• Note: This list is not exhaustive. Please always refer to the device booklet and manual and contact the DBS nurses for further advice.
• X-rays, CT scanners, and mammograms are safe to have, however, patients are advised to inform the doctor or technician. Ultrasound is safe, however, the ultrasound probe should not be applied directly over the implanted battery or cables because this will damage the implanted DBS battery.
• The general rule is that MRI is contraindicated in DBS-implanted patients. However, depending on the model and the make of the implanted DBS device, MRI can be performed under a strict protocol. Please contact the DBS nurses for advice.
• Should a patient need radiation therapy or other forms of therapy, please contact the DBS nurses for advice.

Patients may be asked to participate in research prior to surgery. Participation is entirely voluntary. Refusing or withdrawing from research will not affect your care and medical treatment. However, if in the future you decide to participate in any research project, you must inform the researcher about your DBS implants.

DBS improving voice and speech for laryngeal dystonia patients was first reported from the United States in 2009. Since then, there have been further case reports of laryngeal dystonia patients with their voice and speech symptoms improving with DBS therapy. A phase I randomised clinical trial (the DEBUSSY trial) involving six laryngeal dystonia patients was conducted in Canada in 2021, and this clinical trial confirmed the safety of DBS therapy for laryngeal dystonia whilst showing its good clinical effect.  

The use of DBS in laryngeal dystonia is currently approved and commissioned by the NHS. 

Please be cautious in searching about DBS on Internet. Some information may not be accurate and most likely not be appropriate for your condition (laryngeal dystonia). We advise that you contact the DBS nurses to discuss further information you need. UCLH cannot accept responsibility for information provided by other organisations.

Hariz MI. 2002. Complications of Deep Brain Stimulation Surgery. Mov Disord. 17 Suppl 3:S162-S166. 

Hariz MI, Krack P, Melvill R, et al., 2003. A Quick and Universal Method for Stereotactic Visualization of the Subthalamic Nucleus before and after Implantation of Deep Brain Stimulation Electrodes. Stereotactic and Functional Neurosurgery. 80(1-4):96-101. 

Honey CR, Krüger MT, Almedia T, et al., 2021. Thalamic Deep Brain Stimulation for Spasmodic Dysphonia: A Phase I Prospective Randomized Double-Blind Crossover Trial. Neurosurgery. 89(1):45-52. 

Lee CW, Krüger MT, Akram H, et al., 2024. Central Mechanisms and Pathophysiology of Laryngeal Dystonia: An Up-to-Date Review. Journal of Voice. Available online ahead of print at: https://www.jvoice.org/article/S0892-1997(24)00217-0/abstract  

Lyons MK, Adler CH, Bansberg SF, et al., 2009. Spasmodic dysphonia may respond to bilateral thalamic deep brain stimulation. Afr J Neurol Sci. 28:106-109. 

NHS Commissioning board, 2013. NHS Commissioning Board Clinical Commissioning Policy: Deep Brain Stimulation (DBS) In Movement Disorders (Parkinson’s Disease, Tremor and Dystonia). 

Simonyan K, Barkmeier-Kraemer J, Blitzer A, et al., 2021. Laryngeal Dystonia: Multidisciplinary Update on Terminology, Pathophysiology, and Research Priorities. Neurology. 96(21):989-1001.

Haris Charalambous 
Multi-disciplinary team (MDT) Coordinator  
0203 448 8730 – first point of contact 
haris.charalambous@nhs.net 

DBS Admin Team 

• 0203 448 8726 
• 0203 448 8740 
• 0203 448 8737 
• 0203 448 8719 

DBS Nurse Specialists 

• Joseph Candelario-McKeown 
• Catherine Hartigan 
• Maricel Salazar 
• John Esperida 

Email: uclh.enquiry.dbsnurses@nhs.net  

Website: www.uclh.nhs.uk 
UCLH switchboard telephone number: 020 3456 7890

Travelling to National Hospital for Neurology and Neurosurgery

By Rail

Euston, King’s Cross and St Pancras are all only about 15 minutes walk from the station to the hospital 

By Bus

Southampton Row – Numbers 59, 68, 91, 168, 188, 501 

Theobalds Road – Numbers 19, 38, 55, 243 

High Holborn / New Oxford Street – Numbers 8, 25, 242, 501, 521 

Please note: You can travel on buses and trams using an Oyster or contactless payment card with pay as you go credit, or you can add a Travelcard or Bus & Tram pass to your Oyster card. You are no longer able to use cash to pay for your bus fare. 

By Tube

Russell Square (Piccadilly Line) and Holborn (Central and Piccadilly Lines)  

Both stations are within walking distance. 

Nearest Airport

London City Airport – via DLR from London City Airport to Bank station, transfer to Central Line to Holborn station 

Heathrow Airport – via Piccadilly line about 45 minutes to Russell Square tube station 

Gatwick Airport – via Gatwick Trains to London Victoria Station then take Victoria Line to Green Park station then transfer to Piccadilly line to Russel Square station.