RecruitingNot ApplicableInterventional

Testing the safety of non-invasive transcranial ultrasound stimulation in people with essential tremor

Essential tremor causes involuntary shaking, mostly in the hands, making everyday activities like eating or writing difficult. Current options like medicines or surgery do not work for everyone and can cause unwanted side effects. This clinical trial tests a non-invasive, helmet-shaped device called Meridian. It sends low-intensity sound waves (ultrasound) through the skull to temporarily change activity in a deep part of the brain that controls movement. Unlike older ultrasound treatments, this gentle technique does not burn or destroy brain tissue. The goal of this study is to check whether the device is safe and whether it can temporarily ease hand tremors. Taking part involves a screening visit with an MRI brain scan, one stimulation session lasting around three hours, and a next-day follow-up phone call. While it does not offer a permanent cure, it could help develop new future treatments.

At a glance

Status

Recruiting

Phase

Not Applicable

Sponsor

NeuroHarmonics Ltd

Enrolment target

Start

21 Sep 2026

Estimated completion

21 Mar 2027

Essential tremor

What is this study about?

Essential tremor is a common condition that causes rhythmic, uncontrollable shaking, most often in the hands and arms. Daily tasks like holding a cup of tea, writing a note, or fastening buttons can become difficult and frustrating. While medicines help many people, others find the benefits wear off or experience difficult side effects. Brain surgery is an option for some, but many people understandably prefer to avoid invasive operations.

Researchers at University College London Hospitals are testing a completely non-invasive alternative using sound waves. The trial uses a special helmet called Meridian, which sends low-intensity ultrasound through the scalp and skull. These sound waves target a tiny control centre deep within the brain that regulates shaking. Because the sound waves are gentle, they do not heat up or damage brain cells. Instead, they briefly alter how those cells fire messages.

This is an early-stage study designed to test the safety of the equipment and see if it can produce a measurable, temporary reduction in shaking. Because this is a test of a new technique, taking part will not provide lasting symptom relief. However, the findings will give scientists important knowledge that could lead to new, pain-free treatments for essential tremor in the future.

Key takeaways

Tests a non-invasive ultrasound helmet (Meridian) designed to briefly calm brain signals causing hand tremors.
Open to adults aged 18 to 80 who have experienced hand tremors for at least three years.
Aimed at checking safety and short-term effects, so it does not provide a permanent cure.
Involves a screening visit with an MRI scan, a single three-hour testing session, and a follow-up phone call.
Takes place at University College London Hospitals in London.

Who may be eligible?

This study is open to adults aged 18 to 80 who have had essential tremor affecting both hands for at least three years. To take part, you should have tried standard tremor medicines (such as propranolol or primidone) without enough benefit, experienced unacceptable side effects, or have reasons why you prefer not to take them. If you currently take tremor medication, your dose must have been steady for at least two weeks.

The study is not suitable for everyone. Because the helmet must focus carefully on a specific spot in the brain, participants cannot have significant head shaking or head tremors. The helmet also comes in specific sizes, meaning people with a head circumference over 62 cm (or hair circumference over 80 cm) cannot be fitted properly.

In addition, you must be able to safely have an MRI scan. This means people with heart pacemakers, cochlear implants, or certain metallic implants cannot take part. For safety reasons, anyone with a history of seizures, epilepsy, previous brain surgery, or a recent stroke will also be excluded.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

I am between 18 and 80 years old.
I have had tremor affecting both of my hands for at least three years.
Standard tremor medicines have not worked well, caused bad side effects, or are not suitable for me.
I do not have significant head shaking or head tremors.
I can safely have an MRI scan (no pacemakers or incompatible metal implants).
I have no history of epilepsy, unexplained seizures, or brain surgery.

Answer every question to see your result.

What does participation involve?

Taking part involves two visits to the National Hospital for Neurology and Neurosurgery in London, followed by one telephone call. First, you will attend a screening appointment to check your tremor and have a brain MRI scan to map your head shape. Next, you will return for a single stimulation session lasting around two and a half to three hours. During this visit, you will sit comfortably wearing the Meridian helmet while small sensors on your hands track your tremors. Sound stimulation will be delivered in four separate blocks, one of which will be an inactive 'sham' (dummy) period so researchers can compare the results. Your tremor will then be monitored for up to an hour. The following day, the research team will phone you at home to check how you are feeling.

Potential risks and benefits

Taking part will not cure your tremor or provide lasting relief, as any effects on your shaking are expected to be strictly temporary. However, your involvement will help scientists develop non-invasive treatments for others in the future. Over 700 people have taken part in similar ultrasound studies without serious issues. Potential side effects are usually mild and short-lived, such as a mild headache, scalp tingling, hearing a clicking or buzzing sound during stimulation, or temporary changes in your tremor. Some people may also feel mild discomfort or claustrophobia during the MRI scan. You are free to withdraw from the study at any time without giving a reason, and your normal NHS care will not be affected.

Locations (1)

National Hospital for Neurology and Neurosurgery
Approximate
London, England

Common questions

Will this study permanently stop my tremor?

No. This is an early safety trial designed to test temporary changes in brain signals. Any change in your tremor will only last a very short time.

Does the ultrasound helmet hurt?

No, the sound waves do not cause pain and do not burn tissue. You might feel a slight tingling on your scalp, a mild headache, or hear a quiet buzzing noise.

What is a 'sham' stimulation period?

A sham period is an inactive test where the helmet is on, but no active ultrasound waves are sent. This helps researchers confirm whether any changes are truly caused by the stimulation.

Do I have to stop taking my regular tremor tablets?

Not necessarily. If you take medication, your dose must be steady for at least two weeks before joining. Never stop or change your medicines without speaking to your doctor first.

Where does the study take place?

The trial is based at the National Hospital for Neurology and Neurosurgery, part of University College London Hospitals NHS Foundation Trust in London.

How to find out more

Anna Latorre

a.latorre@ucl.ac.uk +44 20 3448 8066 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.