Glaucoma Rehabilitation Using ElectricAI Transcranial Stimulation (GREAT) - Randomized Controlled Trial Using Combined Perceptual Learning and Transcranial Electrical Stimulation for Vision Enhancement

The Hong Kong Polytechnic University

Status: Enrolling

Conditions: Glaucoma

Treatments: Other: Real-PL training + Real-tES(tDCS); Other: Placebo-PL training + Sham-tES (tDCS); Other: Real-PL training + Sham-tES (tDCS)

Study type: Interventional

Funder types: Other

Identifiers

NCT05874258

HSEARS20190905001

Details and patient eligibility

About

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.

Full 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).

Enrollment: 144 estimated patients

Sex: All

Ages: 18 to 80 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• 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).

Exclusion criteria

• 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 design

Primary purpose: Supportive Care

Allocation: Randomized

Interventional model: Factorial Assignment

Masking: Double Blind

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144 participants in 3 patient groups, including a placebo group

Real-PL + Real-tES (tDCS)

Experimental group

Description:

Participant will receive 30 training sessions with real PL and real tES (tDCS): 3-4 sessions per week, about 1 hour per session

Treatment:

Other: Real-PL training + Real-tES(tDCS)

Real-PL + Sham-tES (tDCS)

Experimental group

Description:

Participant will receive 30 training sessions with real PL and sham tES (tDCS): 3-4 sessions per week, about 1 hour per session

Treatment:

Other: Real-PL training + Sham-tES (tDCS)

Placebo-PL + Sham-tES (tDCS)

Placebo Comparator group

Description:

Participant will receive 30 training sessions with placebo PL and sham tES (tDCS): 3-4 sessions per week , about 1 hour per session

Treatment:

Other: Placebo-PL training + Sham-tES (tDCS)