Hope is Alive, Thanks to You!

Providing hope is the undercurrent of everything we do at the International Essential Tremor Foundation. We want to let people with essential tremor know there is hope for better treatment options, hope for increased understanding, and hope for a cure.

The key component in all of this is research. We have to continue to investigate what causes ET, how it is passed down from one family member to another, what tames it, what stimulates it and how we can stop it.

Since 2001, the IETF has dedicated a portion of its funds annually toward research initiatives. To date, and with your support, we have provided more than $750,000 in research grants. These grants have helped fund a study on gene variants associated with ET and one that identified changes in specific cerebellar proteins that could play a role in ET. They have focused on assistive devices and medications that suppress tremor. And, they have helped to establish the ET Centralized Brain Repository (located at Yale School of Medicine) to study, post mortem, the brains of people with ET.

July is a time when we hold our annual Research Appeal. All money donated during the appeal goes toward our research grants. These grants keep hope alive. They are a promise for a better tomorrow, for a tremor free life for the millions of people who are afflicted with ET.

As you consider donating to our research grant program, take a look at this year’s IETF Research Grant recipients that you helped fund through your 2017 donations. Donations can be made online.

2018 IETF GRANT RECIPIENTS

Research Study Subject: Optogenetic Interrogation of Cerebellar Circuitry of a Novel Mouse Model of Essential Tremor.

Sponsoring Institution: Columbia University

Principal Investigator: Sheng-Han Kuo, MD

Overview: The major obstacle for the effective therapy development for essential tremor is the unclear brain structural alterations that leads to tremor. To overcome this obstacle, we have previously identified structural alterations in the cerebellum, the brain region important for motor coordination, in essential tremor patients. Now, we will determine how this brain pathology can lead to tremor by establishing a mouse model with similar pathological alterations in the cerebellum. We will use the novel neuroscience tools to specifically silence the neuronal activities within the cerebellum in this mouse model and we will assess how these manipulations can influence tremor. The results of our proposal will establish a new platform to screen therapies for essential tremor and will advance our knowledge of essential tremor.

“The continued support for the International Essential Tremor Foundation is instrumental for my research in the tremor field,” Kuo said. Only through the continued research, we can advance our understanding where the tremor comes from in the brain and find ways to treat tremor.”

 

Research Study Subject: A Pilot Study for Quantitative Assessment of Gait in Essential Tremor Using Wireless Sensors; Potential Diagnostic Tool and Measure of Progression

Sponsoring Institution: University of Kansas Medical Center

Principal Investigator: Vibhash Sharma, MD

Although essential tremor (ET) is the most common tremor disorder, its diagnosis can be challenging, and misdiagnosis of ET is not uncommon. The most common movement disorder confused with essential tremor is tremor predominant Parkinson’s disease (PD). Dopamine transporter (DaT) scan is the only available diagnostic tool utilized in the differentiation of ET from PD. However, due to its expense and limited availability it is important to develop a relatively inexpensive tool that can easily and efficiently be utilized in clinical settings to aid in the accurate diagnosis of ET. With growing evidence of gait abnormalities in ET, studying quantitative gait measures may potentially aid in differentiating ET and PD. In this pilot study, we aim to quantitatively analyze gait and balance in the clinical setting using wireless sensors to determine if the gait abnormalities are present in early ET, and whether comparing various aspects of gait and balance can help to differentiate between ET and PD. In this study, we will include patients who have received a DaTscan as part of their clinical care, to help confirm a diagnosis of either ET or PD.  The DaTscan results will be considered the “gold standard” diagnosis, which will be compared to the results of the gait and balance assessments to determine if these assessments can similarly differentiate the patients as either ET or PD.

“The IETF has played a vital role in expanding research in ET,” Sharma said. “This research grant from the IETF will provide a good platform to conduct a pilot study to explore the clinical spectrum of ET related to subtle changes in gait and balance and potentially develop a new tool to aid in the accurate diagnosis of ET.”

Surgical Treatment of Essential Tremor

(This is an article that Dr. Arif Dalvi wrote for our May issue of Tremor Talk magazine. It’s just a sampling of the stories we include in each issue. Annual donors to the IETF receive Tremor Talk magazine in the mail three times per year.)

By Arif Dalvi, MD, MBA
Director of the Comprehensive Movement Disorders Program
Palm Beach Neuroscience Institute 

Background
Many patients with essential tremor (ET) get relief with medications. However, some patients, despite trying multiple medications, have a disabling tremor affecting activities such as eating, writing or using tools. Severe tremor also leads to social embarrassment and isolation. Surgical options can significantly improve quality of life in such patients.

Surgical treatment for ET goes back many decades. Abnormal circuits in a deep brain structure called the thalamus misfire sending signals to the muscles causing a tremor. In the 1970s, Irving Cooper, a neurosurgeon from Columbia University in New York, introduced the idea of making a lesion (similar to a small stroke) in the thalamus to suppress these tremor circuits. However, long term experience shows tremor relief from this method called thalamotomy may wear off in a few years. Patients with tremor in both hands need a thalamotomy on both sides of the brain, leading to higher risk of complications including difficulty with speech compared with a lesion only on one side.

The Birth of DBS
To find the best target the patient undergoes brain mapping while awake. The area within the thalamus is given a test dose of electrical stimulation to see if the tremor subsides. Alim Benabid, a neurosurgeon from Grenoble in France, realized stimulation on a constant basis could provide long-term control of tremor. He developed a brain pacemaker connected to a wire in the brain targeting the thalamus and the idea of deep brain stimulation (DBS) was born. This is the most established surgical technique for control of tremor. DBS was approved by the FDA in 1997 for ET and is covered by Medicare and many private insurers for appropriate patients.

DBS has the advantage of not requiring a stroke-like lesion in the brain. Unlike with a misplaced thalamotomy, side effects can usually be reversed by turning the pacemaker off. Both sides of the brain can be targeted without inducing the kind of complications seen when thalamotomy is done on both sides. DBS settings can be gradually increased over the years if the tremor gets worse. The battery for the DBS pacemaker requires replacement every three to five years. It must be kept in mind that there is approximately a two percent risk of a brain bleed with initial electrode placement.

DBS results depend on accurate placement of the electrode. New types of electrodes allow electrical stimulus to be directed in different directions. These directional electrodes allow for good tremor control while minimizing side effects even without perfect placement. DBS technology continues to improve with directional electrodes, smaller and longer lasting pacemakers, and rechargeable batteries being some of the innovations.

MRI-Focused Ultrasound
MRI-Focused Ultrasound (MRI-FUS) is the most recent surgical option. High energy ultrasound waves are targeted to the thalamus with high-quality MRI imaging. The ultrasound beam makes a lesion like a thalamotomy. The procedure is done on an awake patient in an MRI suite. A lighter test dose is applied to see if tremor improves. If there are no side effects, a full intensity dose is applied. MRI-FUS does not require a burr hole in the skull or electrodes and pacemakers within the body. In this sense, it is “noninvasive,” but a misplaced lesion can still result in permanent side effects. Small numbers of patients with ET have undergone this procedure, usually with favorable results. How these patients will fare in the longer term remains to be seen.

Surgical option choices for severe tremor should be made under the guidance of a movement disorders neurologist highly experienced with these procedures.