Objective: We describe a case of medically refractory orthostatic tremor successfully treated with deep brain stimulation in the ventral intermediate nucleus (Vim) of the thalamus.
Background: Orthostatic tremor (OT) is a rare, high frequency and low amplitude postural tremor involving primarily the lower extremities, characterized by a latent period of onset upon standing, a feeling of unsteadiness, associated falls, and relief with movement. It is difficult to treat and often refractory to medications. The literature reporting surgical treatment of OT is limited and sustained symptomatic improvement on long-term follow up is rarely described.
Method: A 68-year-old woman presented with a history of leg shaking with standing. Her tremor started in the right leg then progressed to involve both lower extremities. Medications including gabapentin and clonazepam improved time to symptom onset on standing, however tremor severity continued to progress and her symptoms spread to involve her trunk and arms. She began having increased falls and was unable to perform activities of daily living.
Results: After nine years of symptoms, the patient underwent DBS implantation in the Vim of the bilateral thalamus. Her symptoms resolved with DBS stimulation and she remains well-controlled at 5 years from implantation. On examination with DBS ON, OT can be felt while holding her legs after standing for 4 minutes but is not noticeable to the patient. With DBS OFF, severe and disabling OT appears with less than 2 minutes standing.
Conclusion: Orthostatic tremor is rare. Data on 17 OT patients treated with Vim-DBS were published by Merola et al in 2017. In contrast to these published cases, our patient had complete resolution of symptoms with DBS ON, despite evidence of mild OT on examination. Our data add to the literature on surgical outcome of Vim-DBS in OT, providing additional information in the critical evaluation of surgical treatment in this difficult to treat condition.
To cite this abstract in AMA style:
D. Sugar, M. Zorn, C. Aquino, J. Rolston, P. Moretti. Treatment of medically refractory orthostatic tremor: deep brain stimulation of bilateral thalamic ventral intermediate nucleus with sustained symptomatic improvement [abstract]. Mov Disord. 2020; 35 (suppl 1). https://www.mdsabstracts.org/abstract/treatment-of-medically-refractory-orthostatic-tremor-deep-brain-stimulation-of-bilateral-thalamic-ventral-intermediate-nucleus-with-sustained-symptomatic-improvement/. Accessed November 21, 2024.« Back to MDS Virtual Congress 2020
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