Category: Other
Objective: To evaluate the efficacy and adverse events of unilateral lesions of the ventral intermediate (VIM) nucleus of the thalamus (thalamotomy) by magnetic resonance guided focused ultrasound (MRgFUS) at 3-month (3m) follow up in a cohort of patients with esential tremor (ET) and tremor dominant Parkinson’s disease (PD) treated at the Clinica Universidad de Navarra (Spain).
Background: The efficacy of unilateral thalamotomies by MRgFUS in tremor has been reported in several studies but larger cohorts of patients are needed.
Method: 135 patients (88 ET, 47 PD) were treated from october 2018 to december 2019. Tremor severity was assessed at baseline and 3m follow-up using the Clinical Rating Scale for Tremor (CRST) in ET patients and items 15, 16, and 17 of the Movement Disorder Society – Unified PD Rating Scale (MDS-UPDRS) part III in patients with PD. Side effects were classified as mild (when they were slight disturbances, such as intermittent paresthesias or ataxia that did not compromise their quality of life), moderate ( when the adverse effect impaired at a partial extent their daily activities), or severe ( if there was an established neurological deficit which implied some level of disability).
Results: 82 patients (mean age 72.8 y.o, female 37%; 58 ET, 24 PD) were evaluated at 3m follow-up. In patients with ET, the CRST score improved 73.94% (baseline 19.69 +/- 5.65; 3m 5.11 +/- 4.53 ). In PD patients, tremor was improved 79.8% (baseline 5.87 +/- 2.02; 3m 1.12 +/- 1.48). The improvement was 100% in 48.7 % of patients with ET and in 48.3% of patients with PD. The most common side effects was gait instability (mild in 14; moderate in 5 and severe in 1 patient) followed by finger paresthesias (11 patients: mild in 10 ,moderate in 1 ) and mild lip/tongue hyposthesia (9 patients ).
Conclusion: MRgFUS thalamotomy for ET and PD is associated with a great improvement in tremor at 3m follow-up. Although side effects are frequent, the vast majority are mild without any clinical relevance.
To cite this abstract in AMA style:
M.C Rodríguez Oroz, O. Parras, A. Gorospe, I. Aviles, P. Manrique, L. Gonzalez, J. Guridi. Efficacy of unilateral thalamotomy by MRgFUS in essential tremor and Parkinson’s disease in a large cohort of patients [abstract]. Mov Disord. 2020; 35 (suppl 1). https://www.mdsabstracts.org/abstract/efficacy-of-unilateral-thalamotomy-by-mrgfus-in-essential-tremor-and-parkinsons-disease-in-a-large-cohort-of-patients/. Accessed June 15, 2025.« Back to MDS Virtual Congress 2020
MDS Abstracts - https://www.mdsabstracts.org/abstract/efficacy-of-unilateral-thalamotomy-by-mrgfus-in-essential-tremor-and-parkinsons-disease-in-a-large-cohort-of-patients/