Coherent Structural and Functional Network Changes after Thalamic Lesions in Essential Tremor

Mov Disord. 2022 Sep;37(9):1924-1929. doi: 10.1002/mds.29130. Epub 2022 Jun 23.


Background: Magnetic resonance-guided focused ultrasound of the ventral intermediate nucleus is a novel incisionless ablative treatment for essential tremor (ET).

Objective: The aim was to study the structural and functional network changes induced by unilateral sonication of the ventral intermediate nucleus in ET.

Methods: Fifteen essential tremor patients (66.2 ± 15.4 years) underwent probabilistic tractography and functional magnetic resonance imaging (MRI) during unilateral postural tremor-eliciting tasks using 3-T MRI before, 1 month (N = 15), and 6 months (N = 10) post unilateral sonication.

Results: Tractography identified tract-specific alterations within the dentato-thalamo-cortical tract (DTCT) affected by the unilateral lesion after sonication. Relative to the treated hand, task-evoked activation was significantly reduced in contralateral primary sensorimotor cortex and ipsilateral cerebellar lobules IV/V and VI, and vermis. Dynamic causal modeling revealed a significant decrease in excitatory drive from the cerebellum to the contralateral sensorimotor cortex.

Conclusions: Thalamic lesions induced by sonication induce specific functional network changes within the DTCT, notably reducing excitatory input to ipsilateral sensorimotor cortex in ET. ©[2022] International Parkinson and Movement Disorder Society. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Keywords: brain networks; essential tremor; magnetic resonance imaging; magnetic resonance-guided focused ultrasound; ventral intermediate nucleus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Essential Tremor*
  • Humans
  • Magnetic Resonance Imaging
  • Parkinson Disease*
  • Thalamus / diagnostic imaging
  • Tremor