Safety and neuromodulation effect of transcranial focused ultrasound for motor recovery in patients with subacute stroke
Journal
Journal of NeuroEngineering and Rehabilitation
ISSN
1743-0003
Date Issued
2026-03-17
Author(s)
Lai, Pin-Hua
Chu, Po-Chun
Liu, Hao-Li
Lai, Ting-Ju
Huang, Abel Po-Hao
Abstract
Transcranial focused ultrasound (tFUS), a non-invasive brain neuromodulation, can target deeper and more precise brain regions compared to transcranial magnetic stimulation. However, its safety, neuromodulation and therapeutic effects in subacute stroke patients remain unclear. Therefore, the aim of this project is to demonstrate the safety and preliminary efficacy of tFUS for upper limb motor recovery in subacute stroke patients. In this phase I single-arm study, we recruited 10 patients with subacute (≤ 3 months) unilateral stroke. tFUS was applied to the contralesional M1 by neuronavigation once daily for five sessions, using ISPTA 2.8 W/cm² in free field (estimated in situ < 0.3 W/cm²), MI 0.75, PRF 100 Hz, and duty cycle 30%, with 10-minute exposure per session. The primary outcome was safety over 12 weeks. Secondary outcomes included cortical excitability (evaluated by transcranial magnetic stimulation and functional near-infrared spectroscopy) and functional measures assessed pre-treatment and at 1 day, 1 week, 4 weeks, and 12 weeks.) RESULTS: Ten patients completed the trial, and the safety analysis revealed no severe adverse events (AEs), new imaging abnormalities, or neuropsychological decline; only minor transient AEs occurred in 5 of 10 patients. tFUS showed preliminary therapeutic efficacy, with improvements in hemiplegic upper limb motor recovery and functional performance. Greater FMA improvement was observed in the tFUS group compared with age-, sex-, and baseline FMA-matched patients who received rTMS. Exploratory analyses of cortical excitability measures showed bilateral trends toward facilitation; however, these changes did not reach statistical significance. tFUS was safe and well tolerated in subacute stroke patients, with only minor transient AEs and no evidence of structural or neuropsychological harm. tFUS demonstrated potential to enhance upper limb motor recovery and functional outcomes. Although exploratory analyses suggested trends toward cortical excitability changes, these findings were not statistically significant and require confirmation in larger controlled trials.
Publisher
Springer Science and Business Media LLC
Type
journal article