Ultrasound-Guided Botulinum Toxin Infiltrations in Essential Tremor Patients: A 36-week Follow Up.

Area of Science:

• Neurology
• Medical Imaging
• Pharmacology

Background:

• Essential tremor (ET) poses treatment challenges due to limited efficacy and adverse effects of oral medications.
• Invasive procedures like Deep Brain Stimulation and High-intensity Focused Ultrasound are effective but costly and invasive.
• Current botulinum toxin treatments for ET have limitations, with ultrasound guidance being under-explored.

Purpose of the Study:

• To evaluate the long-term efficacy of ultrasound-guided IncobotulinumtoxinA (IncoBoNT) infiltrations in improving tremor and quality of life in ET patients.
• To explore a novel anatomo-physiological paradigm for targeted muscle injections in ET.

Main Methods:

• Eighteen ET patients received ultrasound-guided IncoBoNT injections.
• Patients were monitored for 12 months, assessing tremor severity and quality of life.
• An anatomo-physiological paradigm was used for muscle targeting based on tremor patterns (supination/pronation and flexion/extension).

Main Results:

• Significant improvements in TETRAS scores were observed at 36 weeks for both supination/pronation (46.4%) and flexion/extension (48.2%) tremor patterns (p < 0.0022).
• Quality of life scores (QUEST-QOL) also showed substantial improvement (65% and 62.7%, respectively, p < 0.0018).
• All patients demonstrated notable improvements in self-evaluated spiral tests and neurophysiological measures (p < 0.01), with treatment effects lasting 8-12 weeks.

Conclusions:

• Ultrasound-guided IncoBoNT infiltrations represent a promising therapeutic option for essential tremor patients refractory to oral treatments.
• The study demonstrated significant, long-lasting tremor reduction and quality of life enhancement with minimal adverse effects.
• The proposed anatomo-physiological paradigm may enhance treatment precision, though tremor pattern variability requires consideration.