Perceptual Learning Improve Visual Function in Patients With Keratoconus

Study Overview
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Brief Summary
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This project aims at non-progressive keratoconus patients with unsatisfactory visual acuity corrected by spectacles, and explores the effectiveness and maintenance of visual acuity improved by perceptual learning.

Official Title
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A Randomized Controlled Clinical Study of Perceptual Learning Improving Visual Function in Patients With Keratoconus

Conditions
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Keratoconus, Stable

Intervention / Treatment
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* Device: spectacles
* Device: perceptual learning


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged 9 years or older; Has been diagnosed as Keratoconus,BAD-D≥2.6; Change of Kmax < 1.0 D and change of BAD-D <0.4175 betweem the last two Pentacam result; The best corrected visual acuity of both eyes was between 0.1 and 1.0; Has voluntarily agreed to participate in the study by signing the statement of informed consent. Exclusion Criteria: Has history of acute keratoconus; Has other eye diseases or other diseases/conditions causing vision loss; Has eye surgery history in the past 1year; Is currently using local/systemic medications or other interventions that may affect visual function; Receiving other treatments that may affect the results of this study, such as contact lenses during the study; Has any known neurological diseases; Participating in other studies currently that may affect the results of this study; Study other reasons that the physician considers inappropriate for inclusion in the program.

Ages Eligible for Study
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Minimum Age: 9 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Placebo Comparator:placebo practice+spectacles<br>Patients will take placebo practices with spectacles every two days. | Device: spectacles<br>* Spectacle is the the most common treatment for refractive errors.<br>|
| Experimental: Experimental： perceptual learning practice+spectacles<br>Patients will take perceptual learning practices with spectacles every two days. | Device: spectacles<br>* Spectacle is the the most common treatment for refractive errors.<br>Device: perceptual learning<br>* Blurred vision from the eyes can be improved by enhancing the brain's visual processing.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 3-months corrected visual acuity | Mean changes of best corrected visual acuity between 3 months after perceptual learning training and baseline values. | baseline；3 months. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| corrected visual acuity of other time frame | Mean changes of best corrected visual acuity for 6,9,15 months. | 6,9,15 months | 
| ucorrected visual acuity (UCVA) | Mean changes of ucorrected visual acuity (UCVA) for 3,6,9,15 months. | 3,6,9,15 months | 
| contrast sensitivity function (CSF) | Mean changes of contrast sensitivity function (CSF) for 3,6,9,15 months. | 3,6,9,15 months |