Focused ultrasound treatment for essential tremor has been approved by the Food and Drug Administration (FDA) in July 2016. Medicare approved the treatment in all US states as of July 12, 2020.
Essential tremor (ET) is the most common movement disorder, affecting an estimated 3% of the population, or approximately 10 million individuals in the United States. ET is commonly viewed as a relatively benign disease.
However, the associated disabling aspects of ET, such as significant tremor of the hands, can impair patients’ ability to eat, shave, write, perform household activities, and function in the workplace.
The underlying etiology of ET is unclear, but cases often run in families (familial tremor). It has been estimated that approximately 50% of all cases are due to a genetic mutation, and the pattern of inheritance is most consistent with autosomal dominant transmission (i.e. dominant trait).
Focused Ultrasound Therapy
Focused ultrasound is a noninvasive, therapeutic technology with the potential to improve the quality of life and decrease the cost of care for patients with essential tremor. This novel technology focuses multiple beams of ultrasound energy precisely and accurately on targets deep in the brain without damaging surrounding normal tissue.
How it Works
Where the focused ultrasound beams converge, they produce precise ablation (thermal destruction of tissue), enabling ET to be treated noninvasively. The primary target is a region in the thalamus called the ventral intermediate nucleus (Vim), but other adjacent targets and white matter pathways are also in use.
Current treatments are being performed on one side of the brain, but there is a study underway of staged bilateral treatments.
- It is a noninvasive, single treatment that enables patients to recover rapidly and quickly return to activities of normal life (usually the next day).
- Compared to RF ablation or DBS, focused ultrasound offers a reduced risk of infection, of damage to the non-targeted area, and of blood clot formation.
- Focused ultrasound offers rapid resolution of symptoms.
- In contrast to lesioning performed with stereotactic radiosurgery, focused ultrasound does not use ionizing radiation, thus avoiding the side effects of exposure to radiation.
- Because it is non-invasive, focused ultrasound could be an option for medically refractory ET patients (those who do not respond well to medication) who do not want to undergo surgery.
Phase 3 Pivotal Clinical Study
Enrollment has been completed in a multi-center pivotal randomized study to evaluate the safety and efficacy of focused ultrasound for the treatment of medication-refractory essential tremor patients. Results of this study have been reviewed and approved by the FDA.
A clinical trial at the University of Maryland is doing staged bilateral treatments for ET. The interval between treatments will be at least nine months.
A clinical trial in the UK and Spain has begun and is doing staged bilateral treatments. This group will treat the second side after at least nine months have passed after the first treatment.
Please see a list of possible treatment sites here.
Regulatory & Reimbursement
The Exablate system manufactured by Insightec earned FDA approval to treat essential tremor in July 2016. It is also approved for treating essential tremor in Europe, Korea, Canada, Japan, Russia, Taiwan, and the Middle East.
In the US, the Medicare contractors in the various states incrementally approved focused ultrasound treatment for essential tremor. However, on July 12, 2020, all US sites approved for payment under Medicare.
Commercial coverage and Medicaid will typically follow Medicare but should be evaluated with each company and region. Some facilities have a cash payment option, for those who are not willing to wait for insurance decisions for payment. Prices vary, but a rough estimate is $40,000.
Device manufacturer, Insightec has established an informational website, including patient stories and access to treatment site information. They have also set up a Reimbursement Support Manager, who can help with questions about the status of reimbursements. Her contact information is: Kim Martin, Reimbursement Support Manager, 1-(866) 392-8478 or .
Giordano M, Caccavella VM, Zaed I, Foglia Manzillo L, Montano N, Olivi A, Polli FM. Comparison between deep brain stimulation and magnetic resonance-guided focused ultrasound in the treatment of essential tremor: a systematic review and pooled analysis of functional outcomes. J Neurol Neurosurg Psychiatry. 2020 Dec;91(12):1270-1278. doi: 10.1136/jnnp-2020-323216. Epub 2020 Oct 14.
De Vloo P, Milosevic L, Gramer RM, Dallapiazza RF, Lee DJ, Fasano A, Hutchison WD, Lozano AM, Schwartz ML, Kalia SK. Microelectrode Recording and Radiofrequency Thalamotomy following Focused Ultrasound Thalamotomy. Stereotact Funct Neurosurg. 2020 Sep 16:1-4. doi: 10.1159/000510109.
McDannold NJ, White PJ, Cosgrove GR. MRI-based thermal dosimetry based on single-slice imaging during focused ultrasound thalamotomy. Phys Med Biol. 2020 Sep 11. doi: 10.1088/1361-6560/abb7c4.
Jones RM, Huang Y, Meng Y, Scantlebury N, Schwartz ML, Lipsman N, Hynynen K. Echo-Focusing in Transcranial Focused Ultrasound Thalamotomy for Essential Tremor: A Feasibility Study. Mov Disord. 2020 Aug 20. doi: 10.1002/mds.28226.
Su JH, Choi EY, Tourdias T, Saranathan M, Halpern CH, Henderson JM, Pauly KB, Ghanouni P, Rutt BK. Improved Vim targeting for focused ultrasound ablation treatment of essential tremor: A probabilistic and patient-specific approach. Hum Brain Mapp. 2020 Aug 6. doi: 10.1002/hbm.25157.
Saluja S, Barbosa DAN, Parker JJ, Huang Y, Jensen MR, Ngo V, Santini VE, Pauly KB, Ghanouni P, McNab JA, Halpern CH. Case Report on Deep Brain Stimulation Rescue After Suboptimal MR-Guided Focused Ultrasound Thalamotomy for Essential Tremor: A Tractography-Based Investigation. Front Hum Neurosci. 2020 Jun 26;14:191. doi: 10.3389/fnhum.2020.00191. eCollection 2020.
Kapadia AN, Elias GJB, Boutet A, Germann J, Pancholi A, Chu P, Zhong J, Fasano A, Munhoz R, Chow C, Kucharczyk W, Schwartz ML, Hodaie M, Lozano AM. Multimodal MRI for MRgFUS in essential tremor: post-treatment radiological markers of clinical outcome. J Neurol Neurosurg Psychiatry. 2020 Jul 10:jnnp-2020-322745. doi: 10.1136/jnnp-2020-322745.
Ito H, Yamamoto K, Fukutake S, Odo T, Kamei T. Two-year Follow-up Results of Magnetic Resonance Imaging-guided Focused Ultrasound Unilateral Thalamotomy for Medication-refractory Essential Tremor. Intern Med. 2020 Jul 7. doi: 10.2169/internalmedicine.4360-19.
Yamamoto K, Ito H, Fukutake S, Odo T, Kamei T, Yamaguchi T, Taira T. Movement during focused ultrasound therapy caused by an unstable magnetic resonance table: case report. J Neurosurg. 2020 Jul 3:1-4. doi: 10.3171/2020.4.JNS20219.
Buch VP, McShane BJ, Beatson N, Yang A, Blanke A, Tilden D, Korn M, Chaibainou H, Ramayya A, Wombacher K, Maier S, Marashlian T, Wolf R, Baltuch GH. Focused Ultrasound Thalamotomy with Dentato-Rubro-Thalamic Tractography in Patients with Spinal Cord Stimulators and Cardiac Pacemakers. Stereotact Funct Neurosurg. 2020 May 13:1-7. doi: 10.1159/000507031.
Fukutome K, Kuga Y, Ohnishi H, Hirabayashi H, Nakase H. What factors impact the clinical outcome of magnetic resonance imaging guided focused ultrasound thalamotomy for essential tremor? J Neurosurg. 2020 May 1:1-6. doi: 10.3171/2020.2.JNS192814.
Chapman M, Park A, Schwartz M, Tarshis J. Anesthesia considerations of magnetic resonance imaging-guided focused ultrasound thalamotomy for essential tremor: a case series. Can J Anaesth. 2020 Apr 14. doi: 10.1007/s12630-020-01644-1.
Bruno F, Catalucci A, Arrigoni F, Sucapane P, Cerone D, Cerrone P, Ricci A, Marini C, Masciocchi C. An experience-based review of HIFU in functional interventional neuroradiology: transcranial MRgFUS thalamotomy for treatment of tremor. Radiol Med. 2020 Apr 7. doi: 10.1007/s11547-020-01186-y.
Paff M, Boutet A, Neudorfer C, Elias GJB, Germann J, Loh A, Kucharczyk W, Fasano A, Schwartz ML, Lozano AM. Magnetic Resonance-Guided Focused Ultrasound Thalamotomy to Treat Essential Tremor in Nonagenarians. Stereotact Funct Neurosurg. 2020 Mar 30:1-5. doi: 10.1159/000506817.
Gallay MN, Moser D, Jeanmonod D. MR-guided focused ultrasound cerebellothalamic tractotomy for chronic therapy-resistant essential tremor: anatomical target reappraisal and clinical results. J Neurosurg. 2020 Feb 7:1-10. doi: 10.3171/2019.12.JNS192219.
Parras O, Domínguez P, Tomás-Biosca A, Guridi J. The role of tractography in the localization of the Vim nucleus of the thalamus and the dentato-rubro-thalamic tract for the treatment of tremor. Neurologia. 2020 Jan 5. pii: S0213-4853(19)30131-8. doi: 10.1016/j.nrl.2019.09.006. [Epub ahead of print] Review. English, Spanish.
Pouratian N, Baltuch G, Elias WJ, Gross R. American Society for Stereotactic and Functional Neurosurgery Position Statement on Magnetic Resonance-Guided Focused Ultrasound for the Management of Essential Tremor. Neurosurgery. 2019 Dec 12. pii: nyz510. doi: 10.1093/neuros/nyz510.
Halpern CH, Santini V, Lipsman N, Lozano AM, Schwartz ML, Shah BB, Elias WJ, Cosgrove GR, Hayes MT, McDannold N, Aldrich C, Eisenberg HM, Gandhi D, Taira T, Gwinn R, Ro S, Witt J, Jung NY, Chang JW, Rosenberg J, Ghanouni P. Three-year follow-up of prospective trial of focused ultrasound thalamotomy for essential tremor. Neurology. 2019 Dec 10;93(24):e2284-e2293. doi: 10.1212/WNL.0000000000008561. Epub 2019 Nov 20.
Krishna V, Sammartino F, Cosgrove R, Ghanouni P, Schwartz M, Gwinn R, Eisenberg H, Fishman P, Chang JW, Taira T, Kaplitt M, Rezai A, Rumià J, Gedroyc W, Igase K, Kishima H, Yamada K, Ohnishi H, Halpern C. Predictors of Outcomes After Focused Ultrasound Thalamotomy. Neurosurgery. 2019 Nov 6. pii: nyz417. doi: 10.1093/neuros/nyz417.
Sharma S, Pandey S. Treatment of essential tremor: current status. Postgrad Med J. 2019 Oct 1. pii: postgradmedj-2019-136647. doi: 10.1136/postgradmedj-2019-136647.
Pineda-Pardo JA, Urso D, Martínez-Fernández R, Rodríguez-Rojas R, Del-Alamo M, Millar Vernetti P, Máñez-Miró JU, Hernández-Fernández F, de Luis-Pastor E, Vela-Desojo L, Obeso JA. Transcranial Magnetic Resonance-Guided Focused Ultrasound Thalamotomy in Essential Tremor: A Comprehensive Lesion Characterization. Neurosurgery. 2019 Oct 1. pii: nyz395. doi: 10.1093/neuros/nyz395.
Ranjan M, Elias GJB, Boutet A, Zhong J, Chu P, Germann J, Devenyi GA, Chakravarty MM, Fasano A, Hynynen K, Lipsman N, Hamani C, Kucharczyk W, Schwartz ML, Lozano AM, Hodaie M. Tractography-based targeting of the ventral intermediate nucleus: accuracy and clinical utility in MRgFUS thalamotomy. J Neurosurg. 2019 Sep 27:1-8. doi: 10.3171/2019.6.JNS19612.
Miller TR, Zhuo J, Eisenberg HM, Fishman PS, Melhem ER, Gullapalli R, Gandhi D. Targeting of the dentato-rubro-thalamic tract for MR-guided focused ultrasound treatment of essential tremor. Neuroradiol J. 2019 Aug 13:1971400919870180. doi: 10.1177/1971400919870180.
Chang KW, Park YS, Chang JW. Skull Factors Affecting Outcomes of Magnetic Resonance-Guided Focused Ultrasound for Patients with Essential Tremor. Yonsei Med J. 2019 Aug;60(8):768-773. doi: 10.3349/ymj.2019.60.8.768.
Levi V, Eleopra R, Franzini A, Romito L. Is Deep Brain Stimulation still an option for tremor recurrence after Focused Ultrasound thalamotomy? A case report. J Clin Neurosci. 2019 Jul 18. pii: S0967-5868(19)30831-8. doi: 10.1016/j.jocn.2019.07.035.
Sinai A, Nassar M, Eran A, Constantinescu M, Zaaroor M, Sprecher E, Schlesinger I. Magnetic resonance-guided focused ultrasound thalamotomy for essential tremor: a 5-year single-center experience. J Neurosurg. 2019 Jul 5:1-8. doi: 10.3171/2019.3.JNS19466.
Jones RM, Kamps S, Huang Y, Scantlebury N, Lipsman N, Schwartz ML, Hynynen K. Accumulated thermal dose in MRI-guided focused ultrasound for essential tremor: repeated sonications with low focal temperatures. J Neurosurg. 2019 May 10:1-8. doi: 10.3171/2019.2.JNS182995. [Epub ahead of print] PMID: 31075781
D'Souza M, Chen KS, Rosenberg J, Elias WJ, Eisenberg HM, Gwinn R, Taira T, Chang JW, Lipsman N, Krishna V, Igase K, Yamada K, Kishima H, Cosgrove R, Rumià J, Kaplitt MG, Hirabayashi H, Nandi D, Henderson JM, Butts Pauly K, Dayan M, Halpern CH, Ghanouni P. Impact of skull density ratio on efficacy and safety of magnetic resonance-guided focused ultrasound treatment of essential tremor. J Neurosurg. 2019 Apr 26:1-6. doi: 10.3171/2019.2.JNS183517. [Epub ahead of print]
Boutet A, Gwun D, Gramer R, Ranjan M, Elias GJB, Tilden D, Huang Y, Li SX, Davidson B, Lu H, Tyrrell P, Jones RM, Fasano A, Hynynen K, Kucharczyk W, Schwartz ML, Lozano AM. The relevance of skull density ratio in selecting candidates for transcranial MR-guided focused ultrasound. J Neurosurg. 2019 May 3:1-7. doi: 10.3171/2019.2.JNS182571. [Epub ahead of print]
Yang AI, Chaibainou H, Wang S, Hitti FL, McShane BJ, Tilden D, Korn M, Blanke A, Dayan M, Wolf RL, Baltuch GH. Focused Ultrasound Thalamotomy for Essential Tremor in the Setting of a Ventricular Shunt: Technical Report. Oper Neurosurg (Hagerstown). 2019 Mar 19. pii: opz013. doi: 10.1093/ons/opz013.
Pineda-Pardo JA, Martínez-Fernández R, Rodríguez-Rojas R, Del-Alamo M, Hernández F, Foffani G, Dileone M, Máñez-Miró JU, De Luis-Pastor E, Vela L, Obeso JA. Microstructural changes of the dentato-rubro-thalamic tract after transcranial MR guided focused ultrasound ablation of the posteroventral VIM in essential tremor. Hum Brain Mapp. 2019 Mar 13. doi: 10.1002/hbm.24569.
Gasca-Salas C, Guida P, Piredda R, Obeso I, Vela Desojo L, Martínez-Fernández R, Hernández-Fernández F, Máñez-Miró J, Pineda-Pardo JA, Del Álamo M, Rodriguez-Rojas R, Mata-Marín D, Alonso-Frech F, de Luis E, Obeso JA. Cognitive safety after unilateral magnetic resonance-guided focused ultrasound thalamotomy for essential tremor. J Neurol Neurosurg Psychiatry. 2019 Mar 8. pii: jnnp-2018-320129. doi: 10.1136/jnnp-2018-320129.
Harary M, Segar DJ, Hayes MT, Cosgrove GR. Unilateral Thalamic Deep Brain Stimulation vs. Focused Ultrasound Thalamotomy for Essential Tremor. World Neurosurg. 2019 Feb 19. pii: S1878-8750(19)30400-0. doi: 10.1016/j.wneu.2019.01.281.
Park YS, Jung NY, Na YC, Chang JW. Four-year follow-up results of magnetic resonance-guided focused ultrasound thalamotomy for essential tremor. Mov Disord. 2019 Feb 13. doi: 10.1002/mds.27637.
Weidman EK, Kaplitt MG, Strybing K, Chazen JL. Repeat magnetic resonance imaging-guided focused ultrasoundthalamotomy for recurrent essential tremor: case report and review of MRI findings. J Neurosurg. 2019 Jan 25:1-6. doi: 10.3171/2018.10.JNS181721.
Boutet A, Ranjan M, Zhong J, Germann J, Xu D, Schwartz ML, Lipsman N, Hynynen K, Devenyi GA, Chakravarty M, Hlasny E, Llinas M, Lozano CS, Elias GJB, Chan J, Coblentz A, Fasano A, Kucharczyk W, Hodaie M, Lozano AM. Focused ultrasound thalamotomy location determines clinical benefits in patients with essential tremor. Brain. 2018 Nov 17. doi: 10.1093/brain/awy278.
Meng Y, Solomon B, Boutet A, Llinas M, Scantlebury N, Huang Y, Hynynen K, Hamani C, Fasano A, Lozano AM, Lipsman N, Schwartz ML. Magnetic resonance-guided focused ultrasound thalamotomy for treatment of essential tremor: A 2-year outcome study. Mov Disord. 2018 Oct 4. doi: 10.1002/mds.99.
Krishna V, Sammartino F, Agrawal P, Changizi BK, Bourekas E, Knopp MV, Rezai A. Prospective Tractography-Based Targeting for Improved Safety of Focused Ultrasound Thalamotomy. Neurosurgery. 2018 Mar 21. doi: 10.1093/neuros/nyy020.
Jung NY, Park CK, Chang WS, Jung HH, Chang JW. Effects on cognition and quality of life with unilateral magnetic resonance-guided focused ultrasound thalamotomy for essential tremor. Neurosurg Focus. 2018 Feb;44(2):E8. doi: 10.3171/2017.11.FOCUS17625.
Click here for additional references from PubMed.
Pre- and post-treatment assessment videos courtesy of University of Virginia