GlaucomaNCT05874258
Glaucoma Rehabilitation Using ElectricAI Transcranial Stimulation (GREAT) - Randomized Controlled Trial Using Combined Perceptual Learning and Transcranial Electrical Stimulation for Vision Enhancement
A study testing Real-PL training + Real-tES(tDCS) in people with Glaucoma, run by The Hong Kong Polytechnic University at 1 site in Hong Kong.
Trial summary
Glaucoma is a complex disease that can result in progressive vision loss. It is the second leading cause of blindness, accounting for 23% of permanent blindness in Hong Kong. There are no treatments that restore vision lost to glaucoma. Read more about this study
- Who is it for?
- Ages 18 to 80 years
- Conditions the study is for
- Glaucoma
- What is being tested?
- Real-PL training + Real-tES(tDCS)
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 144 participants
- Where
- 1 siteHong Kong
- Study dates
- 15 May 2023to 31 Dec 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 80 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age range from 18 to 80 years;
- Diagnosis of primary open angle or normal tension glaucoma with relative scotoma in both eyes;
- A relative scotoma defined as a Humphrey Field Analyser (HFA) threshold perimetry loss (mean deviation of -6dB) within the central 24 degree of the visual field for at least one eye;
- Best-corrected distance visual acuity of 6/12 or better (equivalent to 0.3 logMAR acuity or better to confirm that participant's central vision is preserved).
- Stable vision and visual field loss for at least 3 months;
- With a cognitive functional score of 22 or above in the Montreal Cognitive Assessment - Hong Kong version (HK-MoCA) (to confirm participant's intact cognitive function).
Who cannot join
- Ocular diseases other than glaucoma (e.g. age-related macular degeneration, diabetic retinopathy, moderate to severe cataract) or severe hearing impairment (to ensure that participant can hear the instructions clearly during assessments and training);
- Severe medical problems (e.g. stroke, Parkinson's disease) or self-reported neurological (e.g. brain surgery, brain tumor, peripheral neuropathy), or cognitive disorders (e.g. diagnosed dementia or cognitive impairment);
- Self-reported vestibular or cerebellar dysfunction, history of vertigo;
- Using any medications for any neurological conditions or psychiatric drugs (e.g. sedative, hypnotic) that might interfere motor control;
- Contraindications for non-invasive brain stimulation.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Hong Kong1 site, 1 recruiting
- Recruiting
The Hong Kong Polytechnic University
Hong Kong
Allen Cheong, PhD, 852-27666108, allen.my.cheong@polyu.edu.hk
Melinna Mei, PhD, 852-34002309, melinna.mei@polyu.edu.hk
About this study
Official title: Improving Vision and Quality of Life in Patients With Glaucoma Using Non-invasive Brain Stimulation and Perceptual Learning: A Randomized Clinical Trial
Glaucoma is a complex disease that can result in progressive vision loss. It is the second leading cause of blindness, accounting for 23% of permanent blindness in Hong Kong. There are no treatments that restore vision lost to glaucoma. However, recent studies have shown that vision can be improved by perceptual learning (PL) and transcranial electrical stimulation (tES). This study will examine the effect of perceptual learning and tES on improving quality of life, visual function and functional performance in patients with peripheral field loss due to glaucoma. It is phase 2 of Glaucoma Rehabilitation Using ElectricAI Transcranial Stimulation (GREAT) project.
Read the detailed description
Study design:
This study uses a prospective, double-masked, randomized, placebo-controlled training RCT design.
The eligible participants will be randomly allocated into 3 groups:
(A) Placebo-Perceptual learning + Sham-tES; (B) Real-Perceptual learning + Sham-tES; (C) Real-Perceptual learning + Real-tES.
All participants will complete forty-three study visits:
Visit 1: Eligibility assessment (refer to the recruitment criteria); Visit 2-3: Outcome measures (Pre-intervention/ baseline); Visit 4-13: 10 sessions intervention (1st batch); Visit 14-15: Interim 1 Outcome measures; Visit 16-25: 10 sessions intervention (2nd batch); Visit 26-27: Interim 2 Outcome measures; Visit 28-37: 10 sessions intervention (3rd batch); Visit 38-39: Post-training 1 Outcome measures; Visit 40-41: Post-training 2 Outcome measures (to evaluate the retention effect after 1 month); Visit 42-43: Post-training 3 Outcome measures (to evaluate the retention effect after 2 months).
Six sessions of assessment will be conducted: (1) Baseline; (2) Interim-1 (after 10-sessions training); (3) Interim-2 (after 20-sessions training); (4) Post-1 (after 30-sessions training); (5) Post-2 (1-month post training); and (6) Post-3 (2-month post training).
- Conditions
- Glaucoma
- Being tested
- Real-PL training + Real-tES(tDCS), Real-PL training + Sham-tES (tDCS), Placebo-PL training + Sham-tES (tDCS)
- Keywords
- glaucoma, transcranial direct current stimulation (tDCS), perceptual learning (PL)
- Medical subject headings
- Glaucoma
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Real-PL training + Real-tES(tDCS)Other
PLtraining : around 40mins, tDCS: 20mins
Real-PL training + Sham-tES (tDCS)Other
PL training : around 40mins, tDCS: 20mins
Placebo-PL training + Sham-tES (tDCS)Other
PL training : around 40mins, tDCS: 20mins
| Study group | Role | What they receive |
|---|---|---|
| Real-PL + Real-tES (tDCS) | Experimental | Participant will receive 30 training sessions with real PL and real tES (tDCS): 3-4 sessions per week, about 1 hour per session Receives: Other: Real-PL training + Real-tES(tDCS) |
| Real-PL + Sham-tES (tDCS) | Experimental | Participant will receive 30 training sessions with real PL and sham tES (tDCS): 3-4 sessions per week, about 1 hour per session Receives: Other: Real-PL training + Sham-tES (tDCS) |
| Placebo-PL + Sham-tES (tDCS) | Placebo comparator | Participant will receive 30 training sessions with placebo PL and sham tES (tDCS): 3-4 sessions per week , about 1 hour per session Receives: Other: Placebo-PL training + Sham-tES (tDCS) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Visual field test
Visual field test is measured monocularly using the 24-2 Swedish interactive threshold algorithm (SITA) standard tests by Humphrey Visual Field Analyzer (HFA, Carl Zeiss Meditec Inc., California). The mean deviation (MD), pattern standard deviation (PSD), and visual field index (VFI) are recorded and the MD of 24-2 visual field test is used as primary outcome of intervention effectiveness.
Measured: Change from baseline at 5weeks, change from baseline at 10weeks, change from baseline at 15weeks, change from baseline at 19weeks, changes from baseline at 23weeks
Secondary outcomes (5)
High Resolution Perimetry (HRP)
The current HRP is a valid and reliable computer-based visual field assessment based upon a previously well-established program. The revised HRP uses circular geometry instead of a rectangle to present stimuli, while maintaining its high-resolution advantage. During the HRP test, suprathreshold stimuli are presented in a radial pattern within 20 degrees, with a step size of 3 degrees. These stimuli are presented monocularly at a total of 98 positions, with the order of presentation randomized. To ensure a stable result and accurate assessment of participants' responses, the HRP test is repeated five times. Throughout the HRP test, fixation is monitored by an infrared eye tracker (SR Research, Eyelink Portable Duo).
Measured: Change from baseline at 5weeks, change from baseline at 10weeks, change from baseline at 15weeks, change from baseline at 19weeks, changes from baseline at 23weeks
Electroencephalography (EEG)
64-channel electroencephalography(EEG) recordings from Neuroscan will be used to understand the electrophysiological changes in the intervention. A standard visual evoked potential task (VEP) and a specific designed SSVEP task will be used to assess the functional integrity of central vision and peripheral function. Besides, resting-state EEG will be recorded to measure the functional connectivity at different timepoints. ERP components (such as P100, N1 and N2) in VEP, tagging frequency response in SSVEP, and the power correlation in resting state will be analyzed as physiological indicators.
Measured: Change from baseline at 15weeks, change from baseline at 19weeks, changes from baseline at 23weeks
Gait Test
All participants will be asked to walk along a 7-m walkway at their normal pace. Two disturbing factors will be introduced while walking: visual searching task and obstacle crossing. For trials with visual search, visual stimuli will be presented on the monitor (located at the end of the walkway) when the participant crosses the obstacle. For trials with obstacle crossing, an obstacle with two different colors (grey for low contrast and yellow for high contrast obstacle) of two different heights (2.5x60x5 cm or 2.5x60x15 cm) are positioned at the middle of the walkway. Participants' gait parameters including hip flexion/extension (degree), knee Min/Max (degree), ankle flexion/extension (degree), head flexion/extension (degree), walking speed (mm/s), step width (mm), and toe clearance(mm) will be measured and analyzed for each condition.
Measured: Change from baseline at 15weeks, change from baseline at 19weeks, changes from baseline at 23weeks
Balance function
Balance function will be evaluated for the following two conditions:
- Static Balance: Participants will be asked to stand on a force place with a foam while performing visual searching. Parameters including maximum antero-posterior amplitude (mm), maximum medio-lateral amplitude (mm), total sway path (mm), and root mean square sway (mm/s) will be analyzed.
- Perturbed Balance: Participants will be asked to stand on a force place which will translate forward or backward while performing visual searching. Parameters including latency (ms) reacting to the perturbation, maximum antero-posterior amplitude (mm), maximum medio-lateral amplitude (mm), total sway path (mm), and root mean square sway (mm/s) will be analyzed.
Measured: Change from baseline at 5weeks, change from baseline at 10weeks, change from baseline at 15weeks, change from baseline at 19weeks, changes from baseline at 23weeks
Questionnaires for QoL
National Eye Institute Visual Function Questionnaire 25 (NEI-VFQ 25) and Low Vision Quality of Life (LVQoL) will be used to evaluate the patient-perceived outcome of the intervention on daily living. In NEI-VFQ 25, more positive person measures indicates greater visual ability, and more negative person measures have less visual ability. In the LVQoL, the completion results in a summed score between 0 (a low quality of life) and 125 (a high quality of life).
Measured: Change from baseline at 15weeks, change from baseline at 19weeks, changes from baseline at 23weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted24 May 2023
- Study start15 May 2023
- Primary completion30 Jun 2026 (estimated)
- Study completion31 Dec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for GlaucomaStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Factorial
- Model description
- A prospective, double-masked, randomized, placebo-controlled training RCT design
- Masking
- Double blind
- Who is masked
- Participant, Outcomes assessor
- Enrolment
- 144 participants (estimated)
Sponsor and investigators
- Lead sponsor
- The Hong Kong Polytechnic University
- Sponsor type
- University, hospital or other
- Collaborators
- The University of Hong Kong, University of Waterloo, University of Magdeburg
- Responsible party
- Principal investigator, Allen MY Cheong, The Hong Kong Polytechnic University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05874258
- Sponsor's protocol ID
- HSEARS20190905001
- Status last verified
- Oct 2024
- First submitted
- 3 May 2023
- Last updated
- 29 Oct 2024
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes
Publications
Jia S, Mei X, Chen L, Chan LH, Tsang C, Suen V, Li T, Zaw MW, Liu A, Thompson B, Sabel B, Woo G, Leung CKS, Yip SP, Chang DHF, Cheong AMY. Glaucoma Rehabilitation using ElectricAI Transcranial Stimulation (GREAT)-study protocol for randomized controlled trial using combined perceptual learning and transcranial electrical stimulation for vision enhancement. Trials. 2024 Jul 22;25(1):501. doi: 10.1186/s13063-024-08314-3.
PubMed 39039582
Study at a glance
From the registry record, last updated by the sponsor on 29 Oct 2024. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Improving Vision and Quality of Life in Patients With Glaucoma Using Non-invasive Brain Stimulation and Perceptual Learning: A Randomized Clinical Trial
- ClinicalTrials.gov ID
- NCT05874258
- Acronym / sponsor ID
- HSEARS20190905001
- Conditions
- Glaucoma
- Keywords
- glaucoma, transcranial direct current stimulation (tDCS), perceptual learning (PL)
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 144 participants (estimated)
- Lead sponsor
- The Hong Kong Polytechnic UniversityUniversity, hospital or other
- Collaborators
- The University of Hong Kong, University of Waterloo, University of Magdeburg
- Study start
- 15 May 2023 (actual)
- Primary completion
- 30 Jun 2026 (estimated)
- Study completion
- 31 Dec 2026 (estimated)
- First posted
- 24 May 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Glaucoma is a complex disease that can result in progressive vision loss. It is the second leading cause of blindness, accounting for 23% of permanent blindness in Hong Kong. There are no treatments that restore vision lost to glaucoma. However, recent studies have shown that vision can be improved by perceptual learning (PL) and transcranial electrical stimulation (tES). This study will examine the effect of perceptual learning and tES on improving quality of life, visual function and functional performance in patients with peripheral field loss due to glaucoma. It is phase 2 of Glaucoma Rehabilitation Using ElectricAI Transcranial Stimulation (GREAT) project.
Detailed description
Study design:
This study uses a prospective, double-masked, randomized, placebo-controlled training RCT design.
The eligible participants will be randomly allocated into 3 groups:
(A) Placebo-Perceptual learning + Sham-tES; (B) Real-Perceptual learning + Sham-tES; (C) Real-Perceptual learning + Real-tES.
All participants will complete forty-three study visits:
Visit 1: Eligibility assessment (refer to the recruitment criteria); Visit 2-3: Outcome measures (Pre-intervention/ baseline); Visit 4-13: 10 sessions intervention (1st batch); Visit 14-15: Interim 1 Outcome measures; Visit 16-25: 10 sessions intervention (2nd batch); Visit 26-27: Interim 2 Outcome measures; Visit 28-37: 10 sessions intervention (3rd batch); Visit 38-39: Post-training 1 Outcome measures; Visit 40-41: Post-training 2 Outcome measures (to evaluate the retention effect after 1 month); Visit 42-43: Post-training 3 Outcome measures (to evaluate the retention effect after 2 months).
Six sessions of assessment will be conducted: (1) Baseline; (2) Interim-1 (after 10-sessions training); (3) Interim-2 (after 20-sessions training); (4) Post-1 (after 30-sessions training); (5) Post-2 (1-month post training); and (6) Post-3 (2-month post training).
Study design
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Factorial
- Masking
- Double blind (participant, outcomes assessor)
- Number of arms
- 3
- Model description
- A prospective, double-masked, randomized, placebo-controlled training RCT design
| Arm | Type | Receives |
|---|---|---|
| Real-PL + Real-tES (tDCS) | Experimental | Other: Real-PL training + Real-tES(tDCS)Participant will receive 30 training sessions with real PL and real tES (tDCS): 3-4 sessions per week, about 1 hour per session |
| Real-PL + Sham-tES (tDCS) | Experimental | Other: Real-PL training + Sham-tES (tDCS)Participant will receive 30 training sessions with real PL and sham tES (tDCS): 3-4 sessions per week, about 1 hour per session |
| Placebo-PL + Sham-tES (tDCS) | Placebo comparator | Other: Placebo-PL training + Sham-tES (tDCS)Participant will receive 30 training sessions with placebo PL and sham tES (tDCS): 3-4 sessions per week , about 1 hour per session |
Who may qualify
- Ages
- 18 to 80 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Age range from 18 to 80 years;
- Diagnosis of primary open angle or normal tension glaucoma with relative scotoma in both eyes;
- A relative scotoma defined as a Humphrey Field Analyser (HFA) threshold perimetry loss (mean deviation of -6dB) within the central 24 degree of the visual field for at least one eye;
- Best-corrected distance visual acuity of 6/12 or better (equivalent to 0.3 logMAR acuity or better to confirm that participant's central vision is preserved).
- Stable vision and visual field loss for at least 3 months;
Key exclusion criteria (5 listed)
- Ocular diseases other than glaucoma (e.g. age-related macular degeneration, diabetic retinopathy, moderate to severe cataract) or severe hearing impairment (to ensure that participant can hear the instructions clearly during assessments and training);
- Severe medical problems (e.g. stroke, Parkinson's disease) or self-reported neurological (e.g. brain surgery, brain tumor, peripheral neuropathy), or cognitive disorders (e.g. diagnosed dementia or cognitive impairment);
- Self-reported vestibular or cerebellar dysfunction, history of vertigo;
- Using any medications for any neurological conditions or psychiatric drugs (e.g. sedative, hypnotic) that might interfere motor control;
- Contraindications for non-invasive brain stimulation.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Real-PL training + Real-tES(tDCS)PLtraining : around 40mins, tDCS: 20mins | Other | Real-PL + Real-tES (tDCS) |
| Real-PL training + Sham-tES (tDCS)PL training : around 40mins, tDCS: 20mins | Other | Real-PL + Sham-tES (tDCS) |
| Placebo-PL training + Sham-tES (tDCS)PL training : around 40mins, tDCS: 20mins | Other | Placebo-PL + Sham-tES (tDCS) |
Primary outcome
Visual field test
Time frame: Change from baseline at 5weeks, change from baseline at 10weeks, change from baseline at 15weeks, change from baseline at 19weeks, changes from baseline at 23weeks
Visual field test is measured monocularly using the 24-2 Swedish interactive threshold algorithm (SITA) standard tests by Humphrey Visual Field Analyzer (HFA, Carl Zeiss Meditec Inc., California). The mean deviation (MD), pattern standard deviation (PSD), and visual field index (VFI) are recorded and the MD of 24-2 visual field test is used as primary outcome of intervention effectiveness.
5 secondary outcomes
High Resolution Perimetry (HRP)
Time frame: Change from baseline at 5weeks, change from baseline at 10weeks, change from baseline at 15weeks, change from baseline at 19weeks, changes from baseline at 23weeks
Electroencephalography (EEG)
Time frame: Change from baseline at 15weeks, change from baseline at 19weeks, changes from baseline at 23weeks
Gait Test
Time frame: Change from baseline at 15weeks, change from baseline at 19weeks, changes from baseline at 23weeks
Balance function
Time frame: Change from baseline at 5weeks, change from baseline at 10weeks, change from baseline at 15weeks, change from baseline at 19weeks, changes from baseline at 23weeks
Questionnaires for QoL
Time frame: Change from baseline at 15weeks, change from baseline at 19weeks, changes from baseline at 23weeks
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Oct 2024.
- Derived from this study: PubMed 39039582Jia S, Mei X, Chen L, Chan LH, Tsang C, Suen V, Li T, Zaw MW, Liu A, Thompson B, Sabel B, Woo G, Leung CKS, Yip SP, Chang DHF, Cheong AMY. Glaucoma Rehabilitation using ElectricAI Transcranial Stimulation (GREAT)-study protocol for randomized controlled trial using combined perceptual learning and transcranial electrical stimulation for vision enhancement. Trials. 2024 Jul 22;25(1):501. doi: 10.1186/s13063-024-08314-3.
- Individual participant dataSharing planned: Yes
Related trials for Glaucoma
Not yet recruiting
Glaucoma Drop Aids Part 2
Glaucoma, Intraocular Pressure
Not yet recruiting
PAUL® Glaucoma Implant Safety and Effectiveness Study
Refractory Glaucoma
Recruiting
The Acute Effect of Exercise Type And Timing on Ambulatory Blood Pressure and Intra-Ocular Pressure in Individuals With Glaucoma (The ACHIEVE-project).
Glaucoma Open-Angle Primary, Hypertension
RecruitingObservational study
Anterior Segment Anatomy Assessed by Swept-Source OCT in Ocular Surgery Patients
Cataract, Primary Angle-Closure Glaucoma
RecruitingObservational study
PRESERFLO™ MicroShunt XI Observational PMCF Study With no Control Group
Primary Open Angle Glaucoma
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Real-PL training + Real-tES(tDCS) in people with Glaucoma, run by The Hong Kong Polytechnic University at 1 site in Hong Kong.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 29 Oct 2024. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Hong Kong. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Allen Cheong, PhD (852-27666108, allen.my.cheong@polyu.edu.hk), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Visual field test (time frame: Change from baseline at 5weeks, change from baseline at 10weeks, change from baseline at 15weeks, change from baseline at 19weeks, changes from baseline at 23weeks). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05874258, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Oct 2024.