An interventional study of NIBS and VTS in Glaucoma Open-Angle, sponsored by The Hong Kong Polytechnic University. Not yet recruiting at 1 site in Hong Kong. Open to participants aged 40 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-03-24.
Sponsored by The Hong Kong Polytechnic University · Not applicable, Interventional, and Treatment
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. This study will examine the effect of transcranial direct current stimulation (NIBS) on improving quality of life, visual function and functional performance in patients with peripheral field loss due to glaucoma.
This study uses a prospective, single-masked, randomized, cross-over, placebo-controlled training RCT design.
The eligible participants will be randomly allocated into 4 groups:
(A) Transcranial direct current stimulation; (B) Visual Tetanic Stimulation; (C) Transcranial direct current stimulation+ Visual Tetanic Stimulation; (D) Sham. All participants will underwent all the 4 types of intervention with a 14 days washing out period between intervention types:
All participants will complete twenty-six study visits:
Visit 1: Eligibility assessment (refer to the recruitment criteria); Visit 2: Outcome measures (Pre-intervention/ baseline); Visit 3-7: 5 sessions intervention (1st intervention block); Visit 8: Post 1 outcome measures; Visit 9-13: 5 sessions intervention (2nd intervention block); Visit 14: Post 2 outcome measures; Visit 15-19: 5 sessions intervention (3rd intervention block); Visit 20: Post 3 outcome measures; Visit 21-25: 5 sessions intervention (4th intervention block); Visit 26: Post 4 outcome measures
Eight sessions of assessment will be conducted: (1) Baseline-1; (2) Post-1 (after 5-sessions training); (3) Baseline-2; (4) Post-2 (after 5-sessions training); (5) Baseline-3; (6) Post-3 (after 5-sessions training); (7) Baseline-4; and (8) Post-4 (after 5-sessions training).
924 studies on the registry are indexed under Glaucoma, Open-Angle; 117 are open to participants now.
This study's planned enrollment of 56 is below the median of 80 across 692 interventional studies indexed under Glaucoma, Open-Angle.
Browse Glaucoma, Open-Angle studies →The Hong Kong Polytechnic University is the lead sponsor of 679 studies on the registry; 257 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Short tests of memory and thinking, each scored out of 30. Lower scores suggest more difficulty; criteria give a range, either to include people with memory problems or to leave them out.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
MMSE and MoCA
Short tests of memory and thinking, each scored out of 30. Lower scores suggest more difficulty; criteria give a range, either to include people with memory problems or to leave them out.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participant will receive 5 training sessions with VTS: about 1 hour per session
Other: VTS
Participant will receive 5 training sessions with NIBS: about 1 hour per session
Other: NIBS
Participant will receive 5 training sessions with NIBS+VTS: about 1 hour per session
Other: NIBS+VTS
Participant will receive 5 training sessions with Sham: about 1 hour per session
Other: Sham
Around 1 hour
Around 1 hour
Around 1 hour
Around 1 hour
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 the 24-2 visual field test will be used as the primary outcome of intervention effect.
Time frame: Baseline (before the first intervention session), and immediately before and after each intervention block (5 session of intervention)
Electroencephalography (EEG)
Electrophysiological function is assessed using a 64-channel high-resolution electroencephalography (EEG) system. EEG outcome measures include spectral power in the delta, theta, alpha, beta, and gamma frequency bands, with particular focus on alpha-band activity, as well as functional connectivity measures derived from scalp EEG recordings, including coherence, phase-based connectivity, and related network indices. Pattern-reversal visual evoked potentials (PR-VEP) are recorded during presentation of a high-contrast checkerboard stimulus to the central 20-degree visual field under monocular viewing conditions. Stimuli are presented at 0.5 Hz and 1.5 Hz with 40 reversals. PR-VEP outcome measures include N75 latency, P100 latency, N135 latency, and N75-P100 and/or P100-N135 amplitude.
Time frame: Baseline (before the first intervention session), and immediately before and after each intervention block (5 session of intervention)
Optical Coherence Tomography (OCT)
Retinal nerve fiber layer is measured using spectral-domain Optical Coherence Tomography (OCT). Peripapillary retinal nerve fiber layer thickness is obtained from a circular scan centered on the optic nerve head. Ganglion cell thickness is measure using macular OCT imaging
Time frame: Baseline (before the first intervention session), and immediately before and after each intervention block (5 session of intervention)
Optical Coherence Tomography Angiography (OCT-A)
Evaluation of retinal vascular function in glaucoma patients is measured. Detailed visualisation of microvasculature structure within the retina and optic nerve head is measured, change of ocular perfusion is shown.
Time frame: Baseline (before the first intervention session), and immediately before and after each intervention block (5 session of intervention)
Plan to share: Yes — De-identified individual participant data (IPD) underlying the results reported in this study will be shared via the Open Science Framework (OSF). These data will include participant-level demographic and clinical characteristics, baseline assessments, intervention-related variables, and primary and secondary outcome data necessary to reproduce the reported analyses. Supporting documents, including the study protocol, statistical analysis plan, data dictionary, and study materials, will also be made available on OSF.
Supporting information: Study protocol, Statistical analysis plan, Informed consent form, Clinical study report, Analytic code
Time frame: De-identified individual participant data and supporting documents will be made available beginning within 6 months after publication of the primary study results and will remain available indefinitely on the Open Science Framework (OSF).
Access criteria: will be publicly available
No publications or documents are linked to this record.
This study is not yet recruiting, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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