BCI-Based Control for Ankle Exoskeleton T-FLEX: Comparison of Visual and Haptic Feedback With Stroke Survivors

Study Overview
=================
Brief Summary
-----------------
This protocol will developed an assessment of the T-FLEX device controlled by Brain-Computer Interface in patients with Stroke.

Detailed Description
-----------------
Brain-Computer Interface (BCI) remains an emerging tool that seeks to improve the patient interaction with the therapeutic mechanisms and to generate neuroplasticity progressively through neuromotor abilities. Motor Imagery (MI) analysis is the most used paradigm based on the motor cortex's electrical activity to detect movement intention. It has been shown that motor imagery mental practice with movement-associated feedback may offer an effective strategy to facilitate motor recovery in brain injury patients. This protocol will study a BCI system associated with visual and haptic feedback to facilitate MI generation and, to control a T-FLEX ankle exoskeleton. In this study, a group of five post-stroke patients will test four different strategies using T-FLEX: Passive movement, Active movement, Motor Imagination with Visual stimulation and Motor Imagination with Visual-Haptic stimuli. The quantitative characterization of BCI performance will be made by using statistical analysis of electroencephalographic data. Finally, the patient's satisfaction will be evaluated by a questionnaire.

Official Title
-----------------
BCI-Based Control for Ankle Exoskeleton T-FLEX: Comparison of Visual and Haptic Feedback With Stroke Survivors

Conditions
-----------------
Stroke

Intervention / Treatment
-----------------
* Device: Implementation of a BCI system integrated to the T-FLEX lower-limb exoskeleton in post-stroke patients.


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Unilateral lower extremity paresis Hemorrhagic or ischemic stroke A minimum of six months after the acute infarction/onset of the disease Full passive range of motion in lower extremity or at least at neutral position Be able to stand freely Be able to walk with or without aid for at least 20 meters in less than 2 minutes Exclusion Criteria: Peripheral nervous system pathology Epilepsy Weight over 100 kg No cognitive ability to follow the study instructions Pregnancy Use of implanted devices Instable lower extremity joints or fixed contracture

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Implementation of a BCI system integrated to the T-FLEX lower-limb exoskeleton in post-stroke<br>The participants will carry out tests for the evaluation of the functionality of the BCI system integrated to the T-FLEX device. The test consists of 1 session that includes four conditional experiments. Real Movement, Continuous Stationary Therapy, Motor Imagery Detection with Visual Stimulation, and Motor Imagery Detection with Tactile Stimulation. | Device: Implementation of a BCI system integrated to the T-FLEX lower-limb exoskeleton in post-stroke patients.<br>* The participants will carry out 4 tasks with a BCI system integrated to the T-FLEX device. The task consists of 1 session that includes 4 conditional experiments: Active ankle movement, passive ankle movement, Motor Imagery Detection with Visual cue, and Motor Imagery Detection with Tactile Stimulation and visual cue.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Response time | The response time for each task will be automatically measured by a Visual Studio Code Software during the use of the Brain-Computer Interface. This variable will consider the response time of a specific command, since the subject receives the stimulation until the software detects the EEG Signal. The measure unit is milliseconds | Baseline | 
| EEG signals from primary motor cortex | continuous signals will be acquired from the primary motor cortex of lower limbs (FcZ, C2, Cz, C1, Cpz) according to the 10-20 International EEG System. Power spectral density in the frequency band of motor imagery (8-32Hz) will be obtained by OpenVibe Software and Matlab. The measure unit is Decibels per Hertz(dB/Hz). | Baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patient satisfaction with device: Quebec User Evaluation of Satisfaction with Assistive Technology | Measured with QUEST scale. The Quebec User Evaluation of Satisfaction with Assistive Technology (QUEST 2.0) is a 12-item outcome measure that assesses user satisfaction with two components, Device and Services. Scores of 1 indicate dissatisfaction and scores of 5 indicate high satisfaction | Baseline | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Stroke, Brain-Computer Interface, Exoskeleton