Deep brain stimulation for the treatment of uncommon tremor syndromes

ABSTRACT

Introduction: Deep brain stimulation (DBS) has become a standard therapy for the treatment of select cases of medication refractory essential tremor and Parkinson’s disease however the effectiveness and long-term outcomes of DBS in other uncommon and complex tremor syndromes has not been well established. Traditionally, the ventralis intermedius nucleus (VIM) of the thalamus has been considered the main target for medically intractable tremors; however alternative brain regions and improvements in stereotactic techniques and hardware may soon change the horizon for treatment of complex tremors.

Areas covered: In this article, we conducted a PubMed search using different combinations between the terms ‘Uncommon tremors’, ‘Dystonic tremor’, ‘Holmes tremor’ ‘Midbrain tremor’, ‘Rubral tremor’, ‘Cerebellar tremor’, ‘outflow tremor’, ‘Multiple Sclerosis tremor’, ‘Post-traumatic tremor’, ‘Neuropathic tremor’, and ‘Deep Brain Stimulation/DBS’. Additionally, we examined and summarized the current state of evolving interventions for treatment of complex tremor syndromes.

Expert commentary: Recently reported interventions for rare tremors include stimulation of the posterior subthalamic area, globus pallidus internus, ventralis oralis anterior/posterior thalamic subnuclei, and the use of dual lead stimulation in one or more of these targets. Treatment should be individualized and dictated by tremor phenomenology and associated clinical features.

KEYWORDS:

• Deep brain stimulation
• dystonic tremor
• Holmes tremor
• cerebellar tremor
• multiple sclerosis tremor
• post-traumatic tremor
• complex tremor syndromes

Acknowledgment

The authors would like to thank Julia Prusik BS and Marcia Lamb for their assistance with the organization of the manuscript.

Declaration of interest

A Ramirez-Zamora has received consultant honoraria from Teva pharmaceuticals. The Phyllis E. Dake Endowed Chair in Movement Disorders supported this study. The institution and not Dr. Ramirez-Zamora receives grant support from Medtronic and Boston Scientific. Dr. Ramirez-Zamora has participated as a site PI and/or co-I for several NIH and industry sponsored trials over the years but has not received honoraria. MS Okun serves as a consultant for the National Parkinson Foundation, and has received research grants from NIH, NPF, the Michael J. Fox Foundation, the Parkinson Alliance, Smallwood Foundation, the Bachmann-Strauss Foundation, the Tourette Syndrome Association, and the UF Foundation. Dr. Okun’s DBS research is supported by R01 NR014852 and R01NS096008. Dr. Okun has previously received honoraria, but in the past >60 months has received no support from industry. Dr. Okun has received royalties for publications with Demos, Manson, Amazon, Smashwords, Books4Patients, and Cambridge (movement disorders books). Dr. Okun is an associate editor for New England Journal of Medicine Journal Watch Neurology. Dr. Okun has participated in CME and educational activities on movement disorders (in the last 36) months sponsored by PeerView, Prime, QuantiaMD, WebMD, MedNet, Henry Stewart, and by Vanderbilt University. The institution and not Dr. Okun receives grants from Medtronic, Abbvie, Allergan, and ANS/St. Jude, and the PI has no financial interest in these grants. Dr. Okun has participated as a site PI and/or co-I for several NIH, foundation, and industry sponsored trials over the years but has not received honoraria. 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.