Condition category
Eye Diseases
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Background and study aims
Anisometropic amblyopia occurs when there is an unequal focus between the eyes. It causes a reduction of the best corrected visual acuity (best distance vision) of the eye without an cause. This condition can lead to permanent vision loss in one eye and limit the vision with both eyes. The main treatments in amblyopia are for children and involve wearing an eye patch over one eye to strengthen the other eye. This treatment is thought to be only effective in the first years of life. A new method of treatment for amblyopia based on the use of a dichoptic (presenting independent and not coordinated stimulus to the eyes) games in a virtual reality environment could help amblyopia for those who are not children. This type of treatment is promising as is non-invasive, without risks associated and motivating for patient as it consists of a game. The aim of this study is to evaluate the effect of dichoptic visual training using a virtual reality head mounted display in a sample of anisometropic amblyopic adults and to evaluate the potential usefulness of this option of treatment.

Who can participate?
Adults aged 17 and older who have anisometropic amblyopia

What does the study involve?
Participants undergo an eye examine prior to the training. Participants receive dichoptic visual training using computer games and a wearable virtual reality system. Participants attend two training sessions a week for one month. Training sessions take 40 minutes and include two different types of games. Participants are followed up for stereopsis (the perception of depth) and visual acuity after their last training session and again three months later.

What are the possible benefits and risks of participating?
There are no notable benefits or risks with participating.

Where is the study run from?
1. Commenius University (Slovakia)
2. University of Alicante (Spain)

When is the study starting and how long is it expected to run for?
May 2016 to October 2016

Who is funding the study?
University of Alicante (Spain)

Who is the main contact?
Dr David Pablo Pinero

Trial website

Contact information



Primary contact

Dr David Pablo Pinero


Contact details

Department of Optics
Pharmacology and Anatomy
University of Alicante
Crta San Vicente del Raspeig s/n
San Vicente del Raspeig

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Amblyopia treatment of adults with Dichoptic training using the Virtual Reality oculus rift head mounted display: Preliminary results



Study hypothesis

Dichoptic visual training using a virtual reality head mounted display is able to restore visual acuity and stereopsis in adults with anisometropic amblyopia.

Ethics approval

Ethics Committe of Jessenius Medical School Commenius University, 08/03/2016, ref: EK 1795/2016

Study design

Prospective interventional non randomised pilot study

Primary study design


Secondary study design

Non randomised study

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet’


Anisometropic amblyopia


Participants all undergo a baseline ophthalmological examination including visual testing, manifest and cycloplegic refraction, cover test, four dot Worth test, anterior segment examination with the slit lamp, corneal topography and funduscopy.

Participants then undergo a dichoptic visual training was performed using the beta version of the computer game Diplopia Game which was run in the Oculus Rift OC DK2 virtual reality head mounted display. Two games are used, a space game in which subjects were flying spaceship through a system of rings and a breaker game which is a typical block breaker game, but played in a virtual reality 3D setting. Both games had a dichoptic setting in which the central part of the picture was different for each eye.

Each participant undergoes eight training sessions, being performed twice a week. Each session included 40 minutes of training with the two different games (20 minutes per game). This takes one month.

Stereopsis and visual acuity were tested after finishing the last session of training (one month after beginning the training) and three months after the end of training.

Intervention type



Drug names

Primary outcome measure

1. Visual acuity is measured using calibrated liquid crystal display (LCD) optotype with Snellen charts (CC-X10, Topcon, Japan) at baseline, one and three months
2. Stereopsis is measured using the Stereo Randot graded circle test (Stereo Optical, IL, USA) at baseline, one and three months

Secondary outcome measures

1. Compliance is measured using the computer registration of the training sessions at one month
2. Refraction is measured using retinoscopy and subjective refraction in trial frame at baseline, one and three months

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Anisometropic amblyopia
2. Age of 17 years old or more
3. Willing to perform the visual training

Participant type


Age group




Target number of participants


Total final enrolment


Participant exclusion criteria

1. Strabismus
2. Previous ocular surgery
3. Corneal irregularity
4. Opacification of ocular media including cataracts
5. Active ocular disease

Recruitment start date


Recruitment end date



Countries of recruitment

Slovakia, Spain

Trial participating centre

Commenius University
Eye Clinic Jessenius Faculty of Medicine Martin L. Novomeského 9
036 01

Trial participating centre

University of Alicante
Department of Optics, Pharmacology and Anatomy Crta San Vicente del Raspeig s/n San Vicente del Raspeig

Sponsor information


Commenius University

Sponsor details

Faculty of Medicine
Špitálska 24
813 72

Sponsor type




Funder type


Funder name

University of Alicante

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Planned publication of the results in BMC Ophthalmology journal.

IPD sharing statement:
The datasets generated during and/or analysed during the current study are/will be available upon request from Peter Ziak, or David P Piñero,

Intention to publish date


Participant level data

Available on request

Basic results (scientific)

Publication list

2017 results in (added 26/11/2020)

Publication citations

Additional files

Editorial Notes

26/11/2020: The following changes were made to the trial record: 1. Publication reference added. 2. The total final enrolment was added.