May 26, 2023

Essential Tremor: Why it’s Undertreated and When to Refer

Essential tremor affects approximately 10 million Americans but, unfortunately, is one of the most undertreated movement disorders.

“Many people think essential tremor isn’t particularly disabling and that patients can just deal with it, but it gets worse over time. Eventually, it can severely impact a person’s ability to do very basic things like typing, writing, drinking or eating with utensils. It also frequently leads to embarrassment, social isolation and depression,” says Ryder Gwinn, MD, a neurosurgeon at the Eastside Neuroscience Institute.

Fortunately, today’s treatments can manage essential tremor and help patients maintain a good quality of life. One of the most effective approaches – deep brain stimulation (DBS) – can reduce tremors by 80% to 95% and is far safer and more effective than many physicians realize.

“It’s natural to worry about bleeding anytime there’s a surgery involving the brain, but DBS has been widely used for many years. There is a less than 1% chance of hemorrhage and an even smaller chance that any bleeding will result in permanent injury,” Dr. Gwinn says.

The Limits of Medication for Essential Tremor

Essential tremor typically starts in one hand and spreads to the other hand. Over time, it can make it difficult to complete many activities of daily living.

“Many people end up isolating themselves because they’re worried about things like going out to dinner and spilling their wine or having people stare at them,” Dr. Gwinn says.

Treatment typically starts with one of the two medications approved for essential tremor: propranolol and primidone. These can diminish a mild tremor but many patients can’t tolerate the medications, which can be accompanied by lethargy, depression and other side effects.

“Typically, medications only reduce the tremor by up to 50%. Even with medication, many patients can get worse or eventually become completely disabled,” Dr. Gwinn says.

How Deep Brain Stimulation Helps with Essential Tremor

The primary interventional treatments for essential tremor are focused ultrasound and DBS. Focused ultrasound is non-incisional and uses ultrasound beams to create a lesion in the part of the brain that causes the tremor. It can reduce tremors by 80%, but side effects such as sensory changes or balance problems, while rare, can be permanent.

Dr. Gwinn and his colleagues at the Eastside Neuroscience Institute typically recommend DBS as a first line treatment due to its reversibility. DBS uses electrical pulses to create a functional lesion that mitigates tremor, rather than creating a permanent lesion.

“We’ve found that DBS offers a very significant tremor reduction, and is adjustable and reversible if there are side effects – the neurons will start functioning normally again as soon as the stimulation ends,” Dr. Gwinn says.

DBS includes three steps:

An initial surgery to place a wire into the ventralis intermedius nucleus (Vim) of the thalamus. This requires a one-night inpatient stay.
A second, outpatient surgery to implant a pulse generator under the skin near the clavicle.
Programming sessions where a physician or nurse practitioner adjusts the output of the device in order to control the tremor.

Unfortunately, right now only about 1% of patients who could benefit from DBS have actually undergone treatment. Dr. Gwinn attributes this to a lack of awareness among patients and even physicians that DBS is safe and can significantly improve quality of life.

“Fortunately, DBS has been around for more than 20 years and the data demonstrate that the risk of bleeding is very low, while the benefit can be quite large,” he says.

How DBS Helped a Woman Get Back to Playing Guitar

We recently used DBS to help a 58-year-old woman who first developed a tremor in her late twenties. The tremor progressed until she struggled to write, cook and play the guitar.

“When she would go to a restaurant, she would think ahead about what to order to be sure she could manage it, and she struggled to participate in a band that was a really important activity for her,” Dr. Gwinn says.

She came to the Eastside Neuroscience Institute after medications didn’t have a significant benefit. We implanted a DBS device in December of 2022. Within a few months, she was back to playing guitar and her quality of life had significantly improved.

When to Refer for Essential Tremor

Dr. Gwinn recommends referring to a movement disorders neurologist when tremor is causing a detrimental effect on daily life and/or when a patient has tried medication and still has a disabling tremor.

“Physicians should also keep in mind that many patients with essential tremor don’t report dysfunction because they’re embarrassed to admit that they have become disabled,” Dr. Gwinn says.

The Eastside Neuroscience Institute takes a collaborative, multidisciplinary approach that considers each patient’s medical condition and goals. Our team includes:

Neurologists who specialize in movement disorders.
Neuropsychologists who help evaluate patients.
Nurse practitioners who help with everything from patient education to programming DBS devices.
A neurosurgery team that utilizes state-of-the-art approaches and technologies, including a NeuroMate robot that helps ensure devices are implanted as accurately as possible.

“When we recommend DBS, it’s the result of a collective approach where we all agree that this treatment is the most appropriate for the patient and gives them the best opportunity for a good quality of life afterwards,” Dr. Gwinn says.

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