- ICH GCP
- US Clinical Trials Registry
- Clinical Trial NCT05362448
Neurophysiologic Assessment of ET Patients Treated by Vim DBS
Assessment of Cerebellar Ataxia Associated With Ventral Intermediate Median Nucleus Deep Brain Stimulation in Essential Tremor: a Multimodal Neurophysiologic Study
Study Overview
Detailed Description
Essential tremor (ET) is a chronic, progressive neurological disease characterized by a symmetrical 4-12 Hz kinetic tremor constantly affecting hands and arms. The tremor can also involve the neck, the lower limb, the voice, the mouth, the tongue or other body regions. ET is among the most frequent movement disorders, with an estimated prevalence of 0,9% of the global population. While the tremor can be mildly disabling at the beginning of the disease, most patients experience a worsening of their tremor over the time. Eventually, disease progression can lead to severe disability, impacting patients' working abilities and in the most severe cases, activity of daily living. Though ET being a frequent debilitating condition, there are still few therapeutic options for the most disabled patients. Several surgical procedures have been evaluated in ET including Deep brain Stimulation (DBS) of Thalamic Ventral intermediate nucleus (Vim) or within the posterior subthalamic area, surgical thalamotomy, Gamma knife or, more recently, MRI guided focused ultrasound thalamotomy. While Gamma knife and focused ultrasound thalamotomy may be safer due to the absence of craniotomy, Vim-DBS remains currently the reference treatment and the most used procedure for medically refractory ET.
Besides the early side effects of Vim-DBS such as haemorrhagic, ischemic and infectious complications occurring immediately after the electrodes implantation procedure, late side-effects such as cerebellar symptoms including gait or upper limb cerebellar ataxia, paraesthesia, dysarthria, dysphagia, and cognitive difficulties are quite frequent. These long-term consequences of the stimulation may dramatically impact the quality of life of patients suffering from ET years after the surgery and mitigate the benefits of this intervention. Considering gait ataxia, it has been reported that this complication may affect up to 37% of ET patients following Vim-DBS surgery and seem to occur more frequently in patient who had pre-operative gait impairment, greater disease severity, older age and when DBS was performed bilaterally. Upper limb ataxia is also common and characterized by the occurrence or the paradoxical worsening of an intention tremor together with asynergy, dyschronometria and dysdiadochokinesia. It has been shown that this latter can be induced by suprathreshold stimulation.
One of the major assets of Vim-DBS over surgical thalamotomy remain its ability to steadily adapt the current delivered by the electrodes by changing the stimulation parameters. Using traditional Implantable Pulse Generator (IPG), it is possible to modify the stimulation mode (monopolar or bipolar stimulation), amplitude, frequency and pulse width as well as to modify the contacts of the electrodes delivering the current. However, despite DBS being a treatment largely available worldwide as well as being part of the routine care for medically refractory tremor, only few studies have assessed the effects of varying DBS settings on cerebellar symptoms presented by patients suffering from ET and stimulated within the Vim. It has been reported that tremor responds best to amplitude, which is usually increased until a complete resolution of the tremor is obtained. Increasing the stimulation pulse width produces a similar clinical effect and may help to alleviate tremor. Interestingly, it has recently been shown that decreasing the pulse width may improve the gait disorders, widen the therapeutic window and diminishes DBS induced side effects. This clinical finding is supported by the recent dissection of the neuronal network underlying Vim DBS clinical response which suggest that tremor suppression could be due to dentato-rubro-thalamic tract stimulation while gait and limb ataxia could be promoted by the stimulation of the cerebello-rubro-spinal and the rubro-olivo-cerebellar tract meaning the possibility of correcting these side effects by accurately optimizing the DBS parameters.
Among the clinical effect of the different types of parameters, the stimulation frequency has certainly been the less extensively studied in ET. This is at first sight quite surprising given that decreasing the frequency of stimulation of the Subthalamic nucleus (STN) is a valuable therapeutic option in Parkinson's disease especially for patient presenting with dopa-refractory symptoms such as freezing of gait or speech impairment. Lower frequency stimulation has also shown to be beneficial for some patients suffering from dystonia, and it has been suggested that this sustained clinical improvement was obtained by avoiding the stimulation of the structure responsible of side effects.
In comparison, a very low number of studies has focused on the consequences of lower frequency stimulation on tremor. Noteworthy is the fact that most of them have pointed that the tremor suppression was better achieved for a frequency around 100 Hz, with little evidence for a small additional therapeutic effect for frequencies above 130 Hz. Conversely, frequency of 50 Hz or lower seems to not suppress tremor and could even worsen it or induce myoclonic jerks. Based on these clinical findings, it is currently admitted initiating the stimulation with a frequency of 130 Hz and increasing it up to 180 Hz if the therapeutic effect on tremor remains unsatisfying despite concomitant high amplitude and large pulse width. A recent small case series has interestingly shown that some patients presenting with balance disorder years after Vim DBS surgery were having their trouble improved when the stimulation frequency was decreased to 130 Hz. Additionally, there are some evidence that, similarly to short pulse width stimulation, decreasing the frequency up to 100 Hz may help to optimize postural or intention tremor and DBS side effects control by widening the therapeutic window. Taken together, these findings suggest that, similarly to shorter pulse width, a lower frequency of stimulation could be an interesting therapeutic approach for ET patients suffering from balance disorders or upper limb ataxia promoted by Vim-DBS. However, since all the above-mentioned studies were unblinded and non-randomized, the level of evidence supporting such a strategy remain weak. Additionally, none of these works has aimed at evaluating the effect of decreasing DBS frequency on gait and balance, neither by using clinical testing, nor by using quantitative measurement such as 3D motion analysis or computerized posture assessment.
For these reasons, the aim of the present study will be to study the effect of varying Vim-DBS frequency on cerebellar features including gait and upper limb ataxia in ET by using non-invasive quantitative physiological tools, namely computerized spiral test analysis, 3D infrared gait motion analysis, balance measure against force perturbation analysis and oculography.
Patients presenting an ET treated by Vim-DBS stimulation for more than 3 months, followed at the National Hospital of Neurology and Neurosurgery, University College London Hospital, London, United Kingdom will be included.
Regarding the procedure, the investigators will first assess the therapeutic window by estimating the therapeutic and side effect thresholds for three different frequencies (80 Hz-130 Hz-180 Hz). Additionally, the investigators will subsequently analyse balance and gait using a 3D motion analysis system, the tremor using a tablet coupled to a computerized spiral analysis software and eye movements using oculography for the three different settings and with the DBS turned off.
Eventually, the investigators will localize the position of the electrodes and model Volume of Tissue Activated using the DBS planning software Guide-XT® and the pre and postoperative brain MRI.
Study Type
Enrollment (Anticipated)
Phase
- Not Applicable
Contacts and Locations
Study Contact
- Name: Patricia Limousin, MD PhD
- Phone Number: +44 02034567890
- Email: p.limousin@ucl.ac.uk
Study Locations
-
-
England
-
London, England, United Kingdom, WC1N 3BG
- Recruiting
- National Hospital For Neurology and Neurosurgery
-
Contact:
- Patricia Limousin, MD PhD
- Phone Number: +44 0203 448 8723
- Email: p.limousin@ucl.ac.uk
-
Contact:
- Thomas Wirth, MD MS
- Phone Number: +44 0203 448 8723
- Email: t.wirth@nhs.net
-
-
Participation Criteria
Eligibility Criteria
Ages Eligible for Study
Accepts Healthy Volunteers
Genders Eligible for Study
Description
Inclusion Criteria:
- Age > 18 years
- No gender specification
- Patient suffering from severe medically intractable essential tremor and treated by Vim-DBS
- Willing and able to provide written informed consent
Exclusion Criteria:
- Concurrent and/or recent involvement in other research that is likely to interfere with the intervention within the last 3 months before study enrolment
- Patients presenting with other cause(s) of balance or gait disorders (stroke, concomitant neurological, rheumatological or orthopaedic disease, severe hypopallesthesia, visual impairment, neuromuscular or vestibular disorders)
- Recently implanted patients (<3 months)
- Patients unable to provide written informed consent (patients presenting with psychiatric or cognitive disorders)
Study Plan
How is the study designed?
Design Details
- Primary Purpose: Basic Science
- Allocation: Randomized
- Interventional Model: Crossover Assignment
- Masking: Triple
Arms and Interventions
Participant Group / Arm |
Intervention / Treatment |
---|---|
Active Comparator: 80 Hz
Stimulation with a frequency of 80 Hz
|
First, we will calculate for each patient and each frequency the amplitude therapeutic window (difference between therapeutic and side effect threshold).
We will determine an optimal amplitude for each frequency that we will apply in the second part of the study.
|
Active Comparator: 130 Hz
Stimulation with a frequency of 130 Hz
|
First, we will calculate for each patient and each frequency the amplitude therapeutic window (difference between therapeutic and side effect threshold).
We will determine an optimal amplitude for each frequency that we will apply in the second part of the study.
|
Active Comparator: 180 Hz
Stimulation with a frequency of 180 Hz
|
First, we will calculate for each patient and each frequency the amplitude therapeutic window (difference between therapeutic and side effect threshold).
We will determine an optimal amplitude for each frequency that we will apply in the second part of the study.
|
Sham Comparator: DBS off
Absence of stimulation
|
First, we will calculate for each patient and each frequency the amplitude therapeutic window (difference between therapeutic and side effect threshold).
We will determine an optimal amplitude for each frequency that we will apply in the second part of the study.
|
What is the study measuring?
Primary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
---|---|---|
Center of Pressure Displacement
Time Frame: 1 day
|
Quantitative continuous variable assessed using balance against force perturbation analysis under the three different DBS settings conditions and with the DBS switched off
|
1 day
|
Secondary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
---|---|---|
Side effect threshold
Time Frame: 1 day
|
Amplitude of DBS stimulation needed to induce side effects under the three DBS settings conditions
|
1 day
|
Therapeutic threshold
Time Frame: 1 day
|
Amplitude of DBS stimulation needed to correct tremor under the three DBS settings conditions
|
1 day
|
Therapeutic window
Time Frame: 1 day
|
Difference between side effect threshold and therapeutic threshold under the three DBS settings conditions
|
1 day
|
Total Energy Delivered
Time Frame: 1 day
|
Energy delivered by the pulse generator under the three different DBS settings conditions
|
1 day
|
Charge density
Time Frame: 1 day
|
Charge delivered by the pulse generator under the three different DBS settings conditions
|
1 day
|
Scale for the Assessment and Rating of Ataxia score
Time Frame: 1 day
|
Scoring of cerebellar ataxia under the three different DBS settings conditions and with the DBS switched off
|
1 day
|
Tremor rating scale score
Time Frame: 1 day
|
Scoring of tremor severity under the three different DBS settings conditions and with the DBS switched off
|
1 day
|
Volume of Tissue Activated
Time Frame: 1 day
|
Prediction through imaging of the volume of tissue activated by stimulation under the three different DBS settings conditions
|
1 day
|
Computerized spiral test analysis (SWVI)
Time Frame: 1 day
|
Comparison of spiral width variability index (SWVI) between the four different conditions
|
1 day
|
Computerized spiral test analysis (AUC)
Time Frame: 1 day
|
Comparison of the Area under the curve (AUC) of the acceleration after Fast Fourier Transform between the four different conditions
|
1 day
|
Computerized spiral test analysis (tremor frequency)
Time Frame: 1 day
|
Comparison of the tremor frequency between the four different conditions
|
1 day
|
Balance motion analysis (CoP initial position)
Time Frame: 1 day
|
Comparison of the center of pressure (CoP) initial position and the resisting force between the four different conditions
|
1 day
|
Balance motion analysis (resisting force)
Time Frame: 1 day
|
Comparison of the resisting force between the four different conditions
|
1 day
|
Gait motion analysis (step length)
Time Frame: 1 day
|
Comparison of step length between the four different conditions
|
1 day
|
Gait motion analysis (number of steps)
Time Frame: 1 day
|
Comparison of the number of steps between the four different conditions
|
1 day
|
Gait motion analysis (stride length)
Time Frame: 1 day
|
Comparison of the stride length between the four different conditions
|
1 day
|
Gait motion analysis (stride velocity)
Time Frame: 1 day
|
Comparison of the stride velocity between the four different conditions
|
1 day
|
Gait motion analysis (normalized double support time)
Time Frame: 1 day
|
Comparison of the normalized double support time between the four different conditions
|
1 day
|
Gait motion analysis (step length asymmetry)
Time Frame: 1 day
|
Comparison of the step length asymmetry between the four different conditions
|
1 day
|
Oculography (fixation index)
Time Frame: 1 day
|
Comparison of the fixation index between the four different conditions using eye tracking system
|
1 day
|
Oculography (saccades velocity)
Time Frame: 1 day
|
Comparison of saccades velocity between the four different conditions using eye tracking system
|
1 day
|
Oculography (saccades latency)
Time Frame: 1 day
|
Comparison of saccades latency (ms) between the four different conditions using eye tracking system
|
1 day
|
Oculography (saccades accuracy index)
Time Frame: 1 day
|
Comparison of saccades accuracy index between the four different conditions using eye tracking system
|
1 day
|
Oculography (VOR gain)
Time Frame: 1 day
|
Comparison of the vestibulo-ocular reflex gain (VOR) between the four different conditions using eye tracking system
|
1 day
|
Collaborators and Investigators
Study record dates
Study Major Dates
Study Start (Actual)
Primary Completion (Anticipated)
Study Completion (Anticipated)
Study Registration Dates
First Submitted
First Submitted That Met QC Criteria
First Posted (Actual)
Study Record Updates
Last Update Posted (Actual)
Last Update Submitted That Met QC Criteria
Last Verified
More Information
Terms related to this study
Keywords
Additional Relevant MeSH Terms
Other Study ID Numbers
- 274481
Plan for Individual participant data (IPD)
Plan to Share Individual Participant Data (IPD)?
Drug and device information, study documents
Studies a U.S. FDA-regulated drug product
Studies a U.S. FDA-regulated device product
product manufactured in and exported from the U.S.
This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.
Clinical Trials on Essential Tremor
-
Emory UniversityCompletedEssential Tremor | Essential Vocal Tremor | Essential Voice Tremor | Voice Tremor | Vocal TremorUnited States
-
Syracuse UniversityNational Institute on Deafness and Other Communication Disorders (NIDCD)CompletedEssential Voice Tremor | Voice Tremor | Vocal Tremor | Essential Tremor of VoiceUnited States
-
ES Therapeutics Australia Pty LtdRecruitingTremor, EssentialCanada
-
InSightecActive, not recruitingNeurologic Manifestations | Tremor | Tremor, EssentialKorea, Republic of, Canada
-
SK Life Science, Inc.CompletedEssential Tremor, Movement Disorders
-
University of MinnesotaRecruitingEssential Tremor | Upper Extremity Essential TremorUnited States
-
Xiangya Hospital of Central South UniversityEnrolling by invitation
-
Merz Pharmaceuticals GmbHCompleted
-
Merz Pharmaceuticals GmbHCompletedEssential Tremor of the Upper LimbUnited States, Canada, Poland
-
University Hospital, Clermont-FerrandAllerganCompletedEssential Head TremorFrance
Clinical Trials on Frequency
-
Centro Universitario La SalleCompletedChronic Pain | Neck Pain | Myofascial Pain SyndromeSpain
-
Capital Medical UniversityCompletedMajor Depressive DisorderChina
-
Zonguldak Bulent Ecevit UniversityCompleted
-
University of California, San FranciscoRecruitingPain, Postoperative | Complex Regional Pain Syndromes | Spinal Cord Injuries | Nerve Injury | Trigeminal Neuralgia | Post-herpetic Neuralgia | Post-Stroke Pain | Nerve Root Avulsion | Chronic Neuropathic PainUnited States
-
University of Alabama at BirminghamUniversity of South AlabamaActive, not recruitingRespiratory Distress Syndrome | Bronchopulmonary Dysplasia | Ventilator-Induced Lung Injury | Preterm InfantUnited States
-
Seoul National University Bundang HospitalCompletedStroke | AphasiaKorea, Republic of
-
Meshalkin Research Institute of Pathology of CirculationCompletedChronic Limb-Threatening IschemiaRussian Federation
-
Seoul National University Bundang HospitalMinistry of Health & Welfare, KoreaTerminatedStroke | HemiplegiaKorea, Republic of
-
University of BirminghamMaastricht UniversityCompletedPhysical ActivityUnited Kingdom
-
Fred Hutchinson Cancer CenterNational Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)Completed