The primary goal of surgery is to reduce or eliminate the tremors of essential tremor. Since the disability from tremor is usually due to difficulty with activities performed by the “dominant” hand (ex. right hand in right-handed people), such as eating, drinking, and writing, surgery is usually only needed on the side of the brain opposite the side of the dominant hand. However, in cases where patients have severe tremors in both hands and need both hands to function effectively for certain activities, or with other tremors in the middle of the body such as voice tremors, surgery on both sides of the brain is considered to provide the most effective treatment.
Focused ultrasound for essential tremor. In 2016, the FDA approved a new, noninvasive treatment for essential tremor; it has now been successfully performed hundreds of times at Weill Cornell Medicine Neurological Surgery.
High-intensity focused ultrasound is an advanced treatment that uses 1,000 precisely targeted beams of ultrasound energy to converge on a single, minuscule spot in the brain that is causing symptoms, particularly tremors. Dr. Michael Kaplitt, a pioneer in the use of this treatment for essential tremor, is now performing it routinely on patients with essential tremor. As of January 2023, with FDA approval, he is now performing the procedure on the second side of the brain in patients who had one side of the brain treated previously and at least nine months have elapsed since the first side was treated.
Find out more about focused ultrasound for relieving tremors.
Deep Brain Stimulation (DBS) is a minimally invasive surgical procedure to treat neurological symptoms of essential tremor.
DBS uses a neurostimulation device — similar to a heart pacemaker — to deliver electrical pulses to a very precise location in the brain circuits that influence symptoms. The abnormal activity in these circuits causes many of the movement problems in essential tremor; the electrical pulses from the DBS device blocks the activity of these circuits so that the rest of the brain can function more normally, resulting in improvement or even complete prevention of tremor.
The procedure involves placing a battery-operated neurotransmitter under the collarbone. The device is connected to a wire implanted under the skin that runs up the length of the neck into the scalp, where it is guided to the brain through a small hole in the skull. The tip of this wire sends the electrical impulses generated by the neurotransmitter into the precise spot in the brain that regulates the activity of the key circuits in essential tremor.
The procedure is usually done in two stages. The first stage, in which the electrode is placed in the brain, is done while the patient is awake in order to provide feedback during surgery and to permit monitoring of brain activity to make sure that the electrode is placed in the correct location. Other than a brief pinch for injection of local anesthetic to numb the skin, there is generally no pain associated with this procedure. Often, testing of the electrode during surgery will result in substantial reduction or elimination of tremor on the operating table. The second stage, in which the neurotransmitter is placed under the collarbone and connected to the end of the electrode left just under the skin, is very similar to that of receiving a heart pacemaker. This second procedure is performed with the patient asleep under general anesthesia, since it does not require any feedback. For essential tremor, these two stages are often performed in a single day, but occasionally they are performed on separate days if it is felt that the patient would better tolerate the second stage after a period of recovery from the first stage.
As with all surgical procedures, DBS poses a small risk of bleeding and infection. There are also potential risks related to the device, such as breakage or movement of a wire. The major benefit of DBS, however, is that it does minimal damage to the surrounding brain tissue, as can happen with other surgeries. The implanted device can also be reprogrammed wirelessly and painlessly without additional surgery, so that the treatment is individualized to each patient, and the therapy can be reversed as technologies advance for improved treatments in the future.
The best candidates for DBS are patients who have tremors with movement and no other major symptoms, but whose tremors are preventing them for properly performing activities such as eating, drinking, and writing to a degree that is harming their quality of life.
Lesioning Surgery
An older alternative to DBS is lesioning surgery, in which a probe is placed into similar brain targets as DBS. Instead of leaving an electrode, the probe is heated to destroy a portion of the brain target. The idea is to eliminate the part of the brain that is firing abnormally in essential tremor. These procedures are usually only performed on one side of the brain, since patients can have increased complications from destroying the same target on both sides of the brain. The effects of lesioning can often wear off over time, and the surgery itself is permanent and cannot be reversed. For all of these reasons, lesioning is performed much less frequently in most centers today and is usually considered only in patients who for some reason are poor candidates for DBS or who have had DBS and cannot tolerate the device due to repeated infections or other unusual complications.
The major type of lesioning for essential tremor is called thalamotomy. This procedure destroys part of the thalamus region of the brain (Vim), which can help in reduce tremors. It is usually not performed on both sides of the brain for those who require both sides treated due to a higher rate of complications. The effects of thalamotomy may also not be as long-lasting as those of DBS.
The Movement Disorders service of Weill Cornell Medicine Neurological Surgery is a leader in the diagnosis and treatment of essential tremor. Led by pioneering researcher and neurosurgeon Michael Kaplitt, MD, PhD, the Movement Disorder service provides state-of-the-art options for essential tremor treatment, including minimally invasive deep brain stimulation surgery.
Reviewed by Michael Kaplitt, MD, PhD
Last reviewed/last updated: July 2024
