Accelerated Transcranial Ultrasound Neuromodulation in Parkinson's Disease: A Pilot Study

Area of Science:

• Neuroscience
• Neuromodulation
• Medical Technology

Background:

• Parkinson's disease (PD) is a neurodegenerative disorder affecting motor function.
• Low-intensity transcranial focused ultrasound (TUS) offers a novel approach for neuromodulation.
• Targeting primary motor cortices (M1) is a potential strategy for PD symptom management.

Purpose of the Study:

• To investigate the feasibility of accelerated theta-burst TUS (a-tbTUS) for stimulating bilateral M1 in PD patients.
• To assess the neurophysiologic and clinical outcomes of a-tbTUS in PD.
• To evaluate the impact of a-tbTUS on motor cortical excitability and motor function.

Main Methods:

• A randomized, sham-controlled crossover design was employed with 10 PD patients.
• Patients received active or sham a-tbTUS, with sessions at least 10 days apart.
• Motor cortical excitability was assessed using transcranial magnetic stimulation (TMS)-elicited motor-evoked potentials (MEPs) before and after TUS.
• Clinical outcomes were evaluated using the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS)-III.

Main Results:

• Active a-tbTUS significantly increased TMS-elicited MEP amplitudes compared to baseline (P=0.0057).
• MEP amplitudes were significantly higher following active a-tbTUS compared to sham sonication (P=0.0064).
• No statistically significant changes in MDS-UPDRS-III scores were observed with either active or sham a-tbTUS.

Conclusions:

• Accelerated theta-burst TUS (a-tbTUS) is a feasible non-invasive neuromodulation strategy that enhances motor cortex excitability in PD.
• While neurophysiologic effects were observed, clinical outcomes did not significantly change in this study.
• Future research should focus on optimizing a-tbTUS dosing parameters and evaluating the long-term durability of its effects in PD patients.