The Impact of Neuronavigation in rTMS for Hemiplegic Stroke Patients.

The Impact of Neuronavigation in Repetitive Transcranial Magnetic Stimulation (rTMS) for Hemiplegic Stroke Patients.

This is a randomized, controlled trial investigating the efficacy and precision of neuronavigation -guided repetitive transcranial magnetic stimulation (rTMS) for motor recovery in patients with subacute stroke hemiparesis.

The primary goal is to determine if using neuronavigation to precisely target the unaffected primary motor cortex (M1) improves treatment accuracy, efficiency, and clinical outcomes compared to conventional manual positioning.

The study will enroll 30 participants with first-ever stroke onset between 2 weeks and 6 months. Participants will be randomized into two parallel groups: the Experimental Group (neuronavigation-guided rTMS) and the Control Group (conventional positioning rTMS). Both groups will receive the same rTMS parameters: 1 Hz stimulation (low-frequency) over the unaffected M1, 1,200 pulses per session, administered for 10 sessions over 2 consecutive weeks.

Primary outcome measures include the change in the Fugl-Meyer Assessment (FMA) Score for the Upper Extremity and the measurement of coil positioning deviation between sessions. Assessments will be conducted at baseline (T0), post-treatment (T1, Week 3), and one month post-treatment (T2, Week 7). This study is funded in part by a research grant from the Metal Industries Research & Development Centre (MIRDC).

This is a single-center, randomized, two-group parallel-assignment interventional trial conducted at Taichung Veterans General Hospital to compare the effectiveness of neuronavigation-guided rTMS versus conventional rTMS in subacute stroke patients with hemiparesis.

Background: Repetitive Transcranial Magnetic Stimulation (rTMS) is recognized for its potential in stroke rehabilitation, with low-frequency (1 Hz) stimulation over the unaffected motor cortex in the subacute phase rated as Grade A (definitely effective) for upper limb motor recovery. However, the efficacy of rTMS is highly dependent on accurate and consistent coil placement over the target cortical area.

Study Hypothesis: We hypothesize that using neuronavigation-which integrates infrared tracking with brain MRI to establish a precise 3D coordinate reference-will significantly increase the treatment precision, reduce the required localization time, and ultimately lead to superior clinical outcomes compared to conventional manual targeting methods.

Intervention Details:

1. Participants: 30 eligible patients (age 20-85) who are 2 weeks to 6 months post-stroke and demonstrate unilateral upper limb weakness will be enrolled.
2. Stimulation Parameters: All participants will receive low-frequency rTMS (1 Hz) at 80% of the motor threshold (RMT). Each session consists of 1,200 pulses delivered over approximately 20 minutes.
3. Grouping:

(1)Experimental Group (n=15): Coil positioning will be guided by a neuronavigational system throughout all 10 sessions. The system tracks the coil and patient's head relative to the initial M1 hotspot.

(2)Control Group (n=15): Coil positioning will rely on standard manual localization (e.g., cap positioning).

Outcome Assessments:

The study will track three primary outcomes: FMA score (a key measure of motor function), coil positioning deviation (a measure of precision), and the time required for initial hotspot localization. Secondary outcomes include functional and spasticity measures such as the Barthel Index (BI), Modified Rankin Scale (mRS), Modified Ashworth Scale (mAS), and neurophysiological parameters (MEP, EEG).

Timeline:

All outcome measures will be assessed at three time points: Baseline (T0), Post-treatment (T1, Week 3), and 1-month Follow-up (T2, Week 7).

Safety:

All adverse events, including rare severe events like seizures (<0.01%) and syncope, will be managed according to standard emergency protocols, and treatment will be discontinued if adverse effects persist or significant clinical weakness occurs. The study protocol is within established safety guidelines.

Inclusion Criteria:

• First-ever ischemic or hemorrhagic stroke confirmed by imaging.
• Stroke causing unilateral upper limb weakness (MRC grade <=3)
• Stroke onset must be between 2 weeks and 6 months prior to enrollment (subacute phase).
• Age between 20 and 85 years old.
• Stable vital signs, clear consciousness, and no cognitive impairment.
• Able to cooperate with assessments and treatment.
• Written informed consent must be signed by the patient or a legal guardian.

Exclusion Criteria:

• Contraindications to TMS (e.g., metallic implants in head, pacemaker, cochlear implant).
• History of epilepsy or seizures.
• Pregnancy.
• Severe cognitive or communication disorders, or inability to give informed consent.
• Unstable medical conditions affecting participation.
• Use of certain medications, including benzodiazepines, antidepressants, muscle relaxants (baclofen, tizanidine), or ongoing botulinum toxin injections for post-stroke spasticity.
• Modified Rankin Scale (mRS) score >=5 .