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Updated: Jan 20, 2026

MRI-guided Focused Ultrasound Thalamotomy for Patients with Medically-refractory Essential Tremor
Published on: December 13, 2017
Focused ultrasound resolves persistent radiosurgery related change in a patient with tremor
Erin L Mazerolle1,2, Graham M Seasons1,3, Robyn Warwaruk-Rogers4
1Department of Radiology, Cumming School of Medicine, University of Calgary, 2905-3330 Hospital Dr NW, Calgary, Alberta T2N 4N1, Canada.
Abstract:
We report on a patient who underwent magnetic resonance guided focused ultrasound (MRgFUS) thalamotomy to treat tremor 3 years after a stereotactic radiosurgery (SRS) thalamotomy. The SRS produced only limited and transient improvements and was associated with a persistent hyperintensity on T2-FLAIR MR images. The MRgFUS thalamotomy was successful, with tremor improvement at 3 months, no adverse effects, and radiological appearance of the MRgFUS lesion similar to other patients undergoing this therapy. We also observed that the SRS-related T2-FLAIR hyperintensity had increased signal intensity 1 day post-MRgFUS, but appeared completely resolved 3 months post-MRgFUS. In conclusion, the case demonstrates that MRgFUS thalamotomy may effectively control tremor in patients with a history of SRS thalamotomy. We also speculate on the potential mechanisms of the apparent resolution of radiation-related change, and discuss possible applications of MRgFUS to reduce persistent SRS-related inflammation.
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