EC Neurology

Magnetic resonance-guided focused ultrasound (MRgFUS) VIM thalamotomy was approved by the FDA and EMA in 2016 as an effective therapy for essential tremor patients (ET). However, there is a debate regarding the brain target for PD-resistant tremor patients (subthalamus, VIM-thalamic nucleus, associative tracts) to be treated with MRg-FUS in these patients. Some studies treating PD-resistant tremor with MRg-FUS in VIM and STN nucleus describe the efficacy on tremor, but also show adverse effects such as dyskinesia and motor deficits in the treated limb, along with a low impact on the quality of life of these patients. Associative tracts of the basal ganglia, particularly the pallido-thalamic and pallido-subthalamic tracts, have been chosen as targets in the past for ablative lesions by radiofrequency to treat PD patients with resistant tremor to oral therapy and motor fluctuations, with good outcomes but some adverse effects.

We present a prospective 12-month follow-up of 10 PD predominant-tremor patients resistant to oral medication who underwent MRg-FUS ablative lesions of the most rostral and ventral VIM thalamic region, located at the border between the thalamus and the zona incerta (cZI), just below the VIM thalamic nucleus. All the cardinal symptoms of PD separately (tremor, rigidity, and bradykinesia), as well as the impact of this therapy on their activities of daily living, were evaluated over a 12-month follow-up period.

 Keywords: Magnetic Resonance-Guided Focused Ultrasound (MRgFUS); Essential Tremor Patients (ET); Zona Incerta (cZI); Parkinson's Disease

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