Deep brain stimulation and other surgical modalities for the management of essential tremor

ABSTRACT

Introduction

Surgical treatments are considered for essential tremor (ET) when patients do not respond to oral pharmacological therapies. These treatments mainly comprise radiofrequency (RF) thalamotomy, gamma knife radiosurgery (GKRS), deep brain stimulation (DBS), and focused ultrasound (FUS) procedures.

Areas covered

We reviewed the strengths and weaknesses of each procedure and clinical outcomes for 7 RF studies (n = 85), 11 GKRS (n = 477), 33 DBS (n = 1061), and 13 FUS studies (n = 368). A formal comparison was not possible given the heterogeneity in studies. Improvements were about 42%–90% RF, 10%–79% GKRS, 45%–83% DBS, 42%–83% FUS at short-term follow-up (<12 months) and were about 54%–82% RF, 11%–84% GKRS, 18%–92% DBS, and 42%–80% FUS at long-term follow-up (>12 months).

Expert opinion

We found DBS with inherent advantages of being an adjustable and reversible procedure as the most frequently employed surgical procedure for control of ET symptoms. FUS is a promising procedure but has limited applicability for unilateral control of symptoms. RF is invasive, and GKRS has unpredictable delayed effects. Each of these surgical modalities has advantages and limitations that need consideration when selecting a treatment for the ET patients.

KEYWORDS:

• Essential tremor
• ET
• deep brain stimulation
• DBS
• thalamotomy
• FUS

Acknowledgments

The authors would like to acknowledge Tyler’s Hope Foundation for dystonia cure.

Author contributions

Qianwei Ren performed the data collection and drafted the manuscript;

Kai-Liang Wang and Fan-gang Meng performed the data analysis, data interpretation and revised the manuscript;

Bhavana Patel was involved in collection of data and critique of manuscript;

Shannon Chiu was involved in collection of data and critique of manuscript;

Wei Hu was involved in collection of data and critique of manuscript;

Aparna Wagle Shukla was involved in conception, organization and execution of research project, review and critique of manuscript.

Declaration of interest

Wagle Shukla reports receiving grants from the NIH and has received grant support from Benign Essential Blepharospasm Research foundation, Dystonia coalition, Dystonia Medical Research foundation, National Organization for Rare Disorders and grant support from NIH (K23 NS092957-01A1); receiving honoraria from Acadia, Cavion, Elsevier and MJFF; and participation as a co-author for several NIH, foundation, and industry-sponsored trials over the years. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer disclosures

One peer reviewer has received grants from NIH, DoD and Medtronic through their employer and is a member of the North American Neuromodulation Society. Peer reviewers on this manuscript have no other relevant financial relationships or otherwise to disclose.

Additional information

Funding

This paper was funded by the NIH (grant nos. K23 NS092957-01A1)