It’s the most well-known condition you’ve never heard of, and often described as more of a nuisance than a disability — uncontrollable shaking of a body part (mostly your hands) where you can’t tie your shoes or hold a glass.
Essential tremor (ET) is the most common form of movement disorder and impacts nearly 10 million Americans. It has posed debilitating conditions on public figures such as former actress Katharine Hepburn and playwright Eugene O’Neill.
Many confuse the tremor with Parkinson’s disease though the nature of the tremor is different. Also, unlike Parkinson’s disease, essential tremor is not considered a progressive neurodegenerative disease.
While most endure symptoms and forego treatment, there are treatment options. These include medications, as well as surgical interventions such as deep brain stimulation and a new FDA-approved treatment that utilizes focused ultrasound and MR imaging to target and treat the brain called Exablate Neuro.
Essential tremor, characterized by kinetic and postural tremors, can emerge at any age, but it is mostly found in adults 40 and older. The condition can and often does get progressively worse, depending on age and disease duration.
With longer disease durations, patients can also develop a degree of gait imbalance.
The majority of cases likely go undiagnosed, or get confused with Parkinson’s disease. Many patients, even those who are impacted by ET, get used to the shaking and never seek medical treatment.
A DaTscan is the lone FDA-approved imaging test to differentiate essential tremor from Parkinson’s, disease, though it cannot actually diagnose ET. A radioactive drug that binds areas of the brain utilizing a neurotransmitter called dopamine is injected, which is then imaged with a single-photon emission computed tomography (SPECT) camera.
An abnormal DaTscan would be consistent with Parkinsonsian disorders, whereas in ET, the scan is expected to be normal.
The majority of essential tremor cases either don’t require treatment, or are treated without surgery. The difference between these tremors and many other diseases is that the kinetic (action) tremor is visible during activities such as holding a cup or spoon, or with writing or drawing.
The first issue to consider for treatment is if the tremor is a problem or disabling? Many people just want to be reassured that it isn’t Parkinson’s disease.
In many patients, one of the features of ET is its responsiveness to alcohol. Unfortunately, this can lead to people self-medicating, which can lead to serious dependency problems (though a small amount of alcohol with dinner may be helpful, especially in public situations).
As for nonpharmacological treatments, you can try using heavier spoons, metal cups or even wrist weights in order to dampen the tremor. A 1/8 or 1/4-lb band may suffice, which can help with eating or holding a cup because the weight dampens the tremor, making some activities more manageable.
Several assistive devices — such as spoons with stabilizing gyroscopes and responsive orthotics — have been developed to help reduce the impact of the tremor, though they tend to be expensive and are not formally approved by the FDA.
There are a number of medications people can use for treatment of essential tremor. The two main medications that have proven to be effective are:
If none of the medications prove sufficient, surgery may be necessary.
Two-thirds of people with essential tremor won’t need treatment, let alone surgical treatment. In fact ET is often managed by a primary care physicians or internist.
If necessary, there are two varieties of surgical treatment: deep brain stimulation (DBS), which is considered the gold standard, and lesion therapy.
Deep brain stimulation has a long track record and works by stimulating the brain via tiny implanted electrodes that connect to a pacemaker-like device implanted beneath the collarbone. This device continuously blocks the abnormal circuitry of the brain, and is beneficial in both essential tremor and Parkinson’s disease. A potential advantage of DBS is that it is reversible and adjustable over time.
Lesion therapy places a surgical lesion in ventral intermediate thalamus. It has shown to be highly beneficial and does not require inserting permanent devices or hardware. However, attempts to control tremors on both sides of the body have increased risk of cognitive difficulty and potential speech issues.
Radiofrequency thalamotomy is another surgical procedure to relieve ET.
Incisionless treatments include thalamotomy via focused ultrasound or stereotactic radiosurgery (gamma knife). Instead of using ultrasound to make the lesion, gamma knife employs radiation to slowly create the same lesion in the same spot of the brain. Gamma knife’s effects develop over several months, whereas focused ultrasound is immediate.
Martin Niethammer, MD, PhD, is a neurologist and movement disorders specialist at North Shore University Hospital and an assistant professor of neurology at the Donald and Barbara Zucker School of Medicine at Hofstra/Northwell.
David Weintraub, MD, is director of functional neurosurgery at North Shore University Hospital and an assistant professor at the Zucker School of Medicine.