A Randomized Controlled Trial of Gabor-Based Perceptual Learning for Adult Amblyopia

NCT07764198 | Recruiting DMC

• 1 other identifier: 20250325.2.1
• Study Type: interventional
• Target: 80
• Locations: 1 country
• Sites: 1

Brief Summary

This study is initiated and conducted by the Shanghai Eye Disease Prevention and Treatment Center / Shanghai Eye Hospital. Many people once believed that amblyopia (commonly known as "lazy eye") could only be treated during childhood (the critical period of visual development) and that nothing could be done once we reached adulthood. However, modern visual science research has revealed that the adult visual cortex still retains a certain degree of "neuroplasticity" (the brain's ability to reorganize, learn, and adapt). The Gabor target training used in this study-powered by RevitalVision software-is a scientifically proven visual training program. By repeatedly performing visual tasks near your perception threshold on a computer screen, this training exercises your eye-brain coordination, helping your brain process visual information much more efficiently. To help you and your family participate with peace of mind, we have compiled the following answers to frequently asked questions: Q1: How will I participate in this study? What is the difference between the two groups? To scientifically compare the training's effectiveness, this study uses a rigorous randomized controlled design. A total of 80 eligible participants will be randomly assigned by a computer program in a 1:1 ratio to one of two groups: Immediate Training Group: You will begin the 12-week home-based Gabor visual training right after randomization. Your study participation ends after your Week 12 follow-up. Delayed Training Group: During the first 12 weeks after randomization, you will simply wear your prescribed glasses and go about your daily life without active visual training. After completing your Week 12 eye evaluation, you will receive the exact same 12-week Gabor visual training for free (conducted from Week 12 to Week 24). Please be assured: No matter which group you are assigned to, every eligible participant will ultimately receive the exact same 12-week professional visual training. This "delayed treatment" design is highly ethical. It ensures everyone gets treated while allowing us to compare the two groups transitionally during the first 12 weeks, thereby ruling out other factors like "getting used to the vision charts" or "gradually adjusting to new glasses". Q2: How is the visual training performed? Is it difficult to do at home? The training is fully home-based, meaning you do not need to visit the hospital constantly. However, it requires your dedication and, ideally, supervision from your family: Training Tools: You will use the specialized RevitalVision perceptual learning software on a calibrated computer monitor. Training Environment: The training should be done in a dark or standard low-light room. Your only main light source should be the computer screen, and you will sit exactly 1.5 meters away. Glasses \& Patching: You must wear your prescribed study glasses during training. If you have monocular (one-sided) amblyopia, you will need to patch your stronger eye (non-study eye), using only your weaker eye (amblyopia eye) to view the screen. Frequency \& Duration: You will train 4 times a week, for about 30 minutes per session, over a continuous span of 12 weeks. The software is adaptive: it automatically adjusts the difficulty of your next session based on your performance to keep you at your optimal training zone. Q3: What do I need to do at the hospital during the study? Your safety and visual health are our top priorities. We will provide meticulous, standardized eye examinations throughout the study: Before the training begins, you will go through an 8- to 12-week "Refractive Stability Phase". During this time, we will perform cycloplegic refraction (dilation) and prescribe your glasses, checking your vision multiple times to ensure your baseline sight is completely stable. During the study, you will only need to visit the clinic for follow-ups at Weeks 6 and 12 (the Delayed Group will also have visits at Weeks 18 and 24). At these visits, our examiners (who do not know which group you are in to ensure objectivity) will measure your vision using standard ETDRS charts, evaluate your contrast sensitivity (using the computerized FrACT test), assess your stereoacuity (3D vision), and capture advanced 3D structural scans of your retina and choroid using Swept-Source OCT. Q4: Is the training safe? What if my vision gets worse? The visual training is entirely physical and non-invasive, with an excellent safety record. In very rare cases, some participants might experience mild, temporary eye strain, headaches, or slight discomfort when they first start training. Double-Safety \& Rescue Protocols: We have set strict "rescue criteria". If at any point during your observation or training, your vision drops significantly or if you experience persistent double vision, we will immediately initiate a professional assessment. If necessary, we will halt the training and provide standard clinical medical care.

Conditions

Amblyopia; Anisometropia

Outcome Measures

Primary Outcomes (1)

• Change in amblyopic-eye ETDRS letters

  Change from randomized baseline in amblyopic-eye ETDRS letters at week 12

Study Arms (2)

Immediate-Training Group

ACTIVE COMPARATOR

Device: Gabor training

Delayed-Training Group

OTHER

Delayed-Training Group: Gabor-Based Perceptual Learning Home-based training will be delayed by 12 weeks.

Device: Gabor training

Interventions

Gabor training DEVICE

Gabor-Based Perceptual Learning: Home-based training will use the RevitalVision visual perceptual-learning software. Training should be conducted in a dark or standardized low-illumination environment, with a calibrated computer display as the primary light source and a viewing distance of 1.5 m. Training modes include single-image, clarity, lateral-masking, and image-shift tasks, with parameters adaptively adjusted according to performance.

Delayed-Training Group; Immediate-Training Group

Eligibility Criteria

• Age: 18 Years - 39 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Written informed consent; age 18-39 years inclusive at randomization.
• Diagnosis of amblyopia, with amblyopic-eye BCVA of approximately 20-70 ETDRS letters (approximately decimal BCVA 0.05-0.6).
• Amblyopia caused by anisometropia, strabismus, or both, meeting the following definitions:
• Anisometropic amblyopia: interocular spherical-equivalent difference ≥1.00 D or astigmatic difference ≥1.50 D in any meridian, with no manifest strabismus at distance or near.
• Strabismic amblyopia: strabismus at distance or near, or a history of strabismus surgery, without meeting the anisometropia criterion.
• Combined-mechanism amblyopia: meeting both the strabismus and anisometropia criteria.
• Completion of standardized optical correction and the 8-12-week stability period; absolute difference between week -4 and week 0 ETDRS scores \<5 letters, with no continuing pretreatment improvement trend.
• Ability to use the study device for home training and accept electronic adherence monitoring.

You may not qualify if:

• Eccentric fixation, clinically significant nystagmus, or inability to complete reliable ETDRS testing.
• Corneal, lenticular, retinal, macular, optic-nerve, or neurologic disease capable of explaining the visual-acuity reduction.
• Study-eye spherical equivalent \<-8.00 D, or high refractive error judged by the investigator to compromise test reliability.
• Recent intraocular surgery or ocular trauma, or extraocular-muscle surgery considered likely to affect outcomes.
• Diplopia at baseline that interferes with safety evaluation, or an unacceptable training risk as judged by the investigator.
• Patching, penalization, other visual training, or treatment likely to affect amblyopia outcomes within the prespecified period before randomization.
• Inability to complete follow-up, understand the tasks, or participation in another clinical study likely to affect outcomes.

Sponsors & Collaborators

• Jiannan Huang: lead

Study Sites (1)

Shanghai Eye Disease Prevention and Treatment Center

Shanghai, China

RECRUITING

MeSH Terms

Conditions

Amblyopia; Anisometropia

Condition Hierarchy (Ancestors)

Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vision Disorders; Sensation Disorders; Neurologic Manifestations; Eye Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Refractive Errors

Central Study Contacts

Yan Xu

CONTACT

021-62982727-856; drxuyan_2004@163.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Shanghai Eye Disease Prevention and Treatment Center

Study Record Dates

• First Submitted: August 9, 2026
• First Posted: August 13, 2026
• Study Start: May 25, 2025
• Primary Completion (Estimated): October 1, 2026
• Study Completion (Estimated): December 1, 2026
• Last Updated: August 13, 2026

Record last verified: 2026-08

Locations

CN (1)