Perceptual Learning Treatment for Amblyopia
Towards Developing a Perceptual Learning Treatment for Amblyopia
Objectives. To develop a new treatment for amblyopia using a perceptual learning approach.
Hypothesis to be tested. Our proposed experiments are designed to investigate whether practicing a grating detection task can improve vision in patients with amblyopia.
Design and subjects. A total of 36 patients with amblyopia will be randomized allocated into two intervention groups: Group 1, perceptual learning therapy. Group 2, occlusion therapy. A control group comprising of 18 subjects with normal vision will be recruited for comparison. A battery of tests will be used to assess a range of visual functions before and after the treatment intervention.
Study instruments. Grating acuity testing system
Interventions. We have established a clinical protocol for acuity training. On each trial, a properly oriented stimulus will be presented randomly at one of the four locations on a flat monitor screen. The visual task is to indicate the location of the stimulus. Participants will be required to undertake 20 one-hour sessions of training.
Main outcome measures. Resolution acuity, visual acuity, contrast sensitivity function
Study Overview
Status
Status
Conditions
Conditions
Intervention / Treatment
Intervention / Treatment
Study Type
Study Type
Enrollment (Actual)
Enrollment
Phase
Phase
- Not Applicable
Contacts and Locations
Study Locations
-
-
-
Hong Kong, Hong Kong
- Optometry Research Clinic
-
-
Participation Criteria
Eligibility Criteria
Eligibility Criteria
Ages Eligible for Study
Accepts Healthy Volunteers
Description
Inclusion Criteria:
- Visual acuity in the amblyopic eye: 20/25 or worse
Exclusion Criteria:
- Manifest eye disease & nystagmus
Study Plan
How is the study designed?
Design Details
- Primary Purpose: Treatment
- Allocation: Non-Randomized
- Interventional Model: Parallel Assignment
- Masking: None (Open Label)
Number of Arms
Arms and Interventions
Participant Group / ArmParticipant Group / Arm |
Intervention / TreatmentIntervention / Treatment |
|---|---|
|
Experimental: Perceptual learning group - Amblyopia
Visual training
|
The intervention will be a vision therapy.
On each trial, a properly oriented stimulus will be presented randomly at one of the four locations on a flat monitor screen.
The visual task is to identify the location of the stimulus.
|
|
Active Comparator: Perceptual learning group - Control
Visual training
|
The intervention will be a vision therapy.
On each trial, a properly oriented stimulus will be presented randomly at one of the four locations on a flat monitor screen.
The visual task is to identify the location of the stimulus.
|
|
Placebo Comparator: Occlusion therapy - Amblyopia
Patching
|
Participants will be required to patch the good eye for 20 days, 1 hour per day.
|
What is the study measuring?
Primary Outcome Measures
Primary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
|---|---|---|
|
Change of grating acuity
Time Frame: 20 hours
|
Grating acuity tests the participants' ability to resolve fine details.
This study measures the change of grating acuity after 20 hours of vision training.
|
20 hours
|
Secondary Outcome Measures
Secondary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
|---|---|---|
|
Change of visual acuity
Time Frame: 20 hours
|
Visual acuity tests the participants' ability to resolve letters.This study measures the change of visual acuity after 20 hours of vision training.
|
20 hours
|
|
Change of contrast sensitivity
Time Frame: 20 hours
|
Contrast sensitivity reflects the participants' sensitivity to identify low contrast visual stimuli.
This study measures the change of contrast sensitivity after 20 hours of vision training.
|
20 hours
|
|
Change of stereopsis
Time Frame: 20 hours
|
Visual acuity tests the 3-D perception.
This study measures the change of stereopsis after 20 hours of vision training.
|
20 hours
|
Collaborators and Investigators
Sponsor
Sponsor
Investigators
Investigators
- Principal Investigator: Tsz Wing Leung, Ph.D., The Hong Kong Polytechnic University
Publications and helpful links
General Publications
- Li RW, Klein SA, Levi DM. Prolonged perceptual learning of positional acuity in adult amblyopia: perceptual template retuning dynamics. J Neurosci. 2008 Dec 24;28(52):14223-9. doi: 10.1523/JNEUROSCI.4271-08.2008.
- Li RW, Ngo C, Nguyen J, Levi DM. Video-game play induces plasticity in the visual system of adults with amblyopia. PLoS Biol. 2011 Aug;9(8):e1001135. doi: 10.1371/journal.pbio.1001135. Epub 2011 Aug 30.
- Levi DM, Li RW. Improving the performance of the amblyopic visual system. Philos Trans R Soc Lond B Biol Sci. 2009 Feb 12;364(1515):399-407. doi: 10.1098/rstb.2008.0203.
Study record dates
Study Major Dates
Study Start (Actual)
Study Start
Primary Completion (Actual)
Primary Completion
Study Completion (Actual)
Study Completion
Study Registration Dates
First Submitted
First Submitted
First Submitted That Met QC Criteria
First Submitted That Met QC Criteria
First Posted (Actual)
First Posted
Study Record Updates
Last Update Posted (Actual)
Last Update Posted
Last Update Submitted That Met QC Criteria
Last Update Submitted That Met QC Criteria
Last Verified
Last Verified
More Information
Terms related to this study
Additional Relevant MeSH Terms
Other Study ID Numbers
Other Study ID Numbers
- HSEARS20171108002
Plan for Individual participant data (IPD)
Plan to Share Individual Participant Data (IPD)?
Drug and device information, study documents
Studies a U.S. FDA-regulated drug product
Studies a U.S. FDA-regulated device product
This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.