Clinical Trial Details
— Status: Recruiting
Administrative data
NCT number |
NCT05965960 |
Other study ID # |
20-5740#2 |
Secondary ID |
|
Status |
Recruiting |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
May 18, 2023 |
Est. completion date |
June 1, 2024 |
Study information
Verified date |
July 2023 |
Source |
University Health Network, Toronto |
Contact |
Julian Kwok |
Phone |
1 416 603 5800 |
Email |
julian.kwok[@]uhn.ca |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
Transcranial Ultrasound Stimulation (TUS) is an emerging non-invasive brain stimulation(NIBS)
technique that can be used on both superficial and deep brain targets with a high spatial
resolution as small as a few cubic millimeters. Neural correlates of TUS have yet been
elucidated. To date, no intracranial recordings (i.e., local field potential [LFP]) have been
captured during or after TUS in patients with movement disorders. In this study, we are
aiming to profile basal ganglia LFP activity during and after TUS by using a DBS system that
is capable of recording LFP. This can shed light on mechanisms of TUS, as well as allow
identification of a neurophysiological biomarker that can be used to tune the TUS sonication
parameters for future clinical trials.
Description:
Experiment 1: Subjects will be randomly assigned to either the sham or active stimulation
group during the first study visit. In the second study visit, there will be a crossover
between the groups, with all subjects undergoing one sham and one active stimulation visit
before the study is completed. During the active stimulation visit, a theta burst protocol
(Isppa: 30 W/cm2, burst length: 20 ms, period: 200 ms, frequency 500 kHz) will be used to
sonicate the bilateral primary motor cortices (M1) or globus pallidus interna (GPi) for 2
minutes. The sham group involves sonications performed with the power set to 0 watts over
bilateral M1s/GPis. In both groups, the subjects will be masked using white noise transmitted
through earbuds. The targets will be identified anatomically using structural MRIs and a
neuronavigation system.
The Percept PC DBS system will be used to record local field potentials (LFPs) from the
subthalamic nucleus (STN) or globus pallidus internus (GPI) at various time points: before
(baseline) and during the sonications, as well as at 10-, 30-, and 45-minute intervals after
the sonications. These recordings will be obtained while the subjects engage in a finger
tapping task monitored by an accelerometer, as well as during resting periods. The power of
LFPs across different frequencies will be compared and correlated with the velocity observed
during the finger tapping task.
Following the completion of sham and active stimulation visits, the subjects will have the
opportunity to participate in an optional control group visit, which entails sonication of
the occipital cortex utilizing the theta burst protocol.
Experiment 2: TUS will be utilized to target the area directly over the DBS lead, while
concurrently recording LFPs to identify any stimulation artifact indicative of target
area-sonication engagement.