Will Perceptual Learning Via Video Game Playing Improve Visual Acuity Stereopsis & Fixation Stability in Mild Amblyopes?

Amblyopia Clinical Trial

Official title:

Will Perceptual Learning Via Video Game Playing Improve Visual Acuity, Stereopsis and Fixation Stability in Mild Amblyopes? Part 2 Study

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02995174
• Other study ID #: HMRF11122991
• Status: Completed
• Phase: N/A
• Start date: August 2015
• Est. completion date: December 31, 2018

Study information

• Verified date: August 2020
• Source: The Hong Kong Polytechnic University
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Contrast balanced dichoptic videogame training has been found to improve sensory functions in adults with amblyopia; best corrected distance visual acuity (BCVA) and stereopsis, but its effect on motor function, namely amblyopic eye fixation stability, is unknown. Furthermore, the effect of treatment in cases of mild amblyopia is not well understood. The aim of this study is to find out the difference on fixation stability, BCVA and stereopsis in mild amblyopes after 6 weeks' contrast balanced dichoptic video game training.

Description:

Objectives: To assess the change of fixation stability as well as visual acuity and stereopsis before and after training mild amblyopia by perceptual learning through dichoptic video game playing.

Hypothesis: It has been shown that the visual acuity, stereopsis and fixation stability are compromised in amblyopic eye. Perceptual learning via video game playing has been found effective in improving visual acuity and stereoacuity in moderate and severe amblyopic eyes, but there is no study on such treatment in mild amblyopia. In this study, we hypothesize that fixation stability, visual acuity and stereopsis will be improved after training by dichoptic video game playing in mild amblyopia.

Methods: Participants (aged 7 or above) with Best Corrected Visual Acuity (BCVA) ≤ 0.28 logMAR in the amblyopic eye and an interocular acuity difference ≥ 0.2 logMAR will be recruited. An anaglyphic, contrast balanced dichoptic video game will be provided on an i-Pod Touch (Apple Inc.) for 6 weeks of home-based training (60 mins per day). Fixation stability quantified using bivariate contour ellipse area (BCEA by micro-perimeter (MP) Nidek MP-1), BCVA and stereopsis will be assessed before and after treatment.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 23
• Est. completion date: December 31, 2018
• Est. primary completion date: December 18, 2017
• Accepts healthy volunteers: No
• Gender: All
• Age group: 7 Years and older

Eligibility

Inclusion Criteria:

• Best corrected VA in amblyopic eye = 0.28 log MAR, fellow eye VA with an interocular VA difference = 0.20 log MAR;

• Amblyopia could be in form of strabismic, anisometropic and mixed (both strabismic and anisometropic)

• Able to complete 3 successful measurements (each with 30 seconds fixation) of BCEA by the MP-1 systems in each eye

• Able to align the nonius cross (=10mm horizontal error and 5mm vertical error) in the i-Pod game

Exclusion Criteria:

• Myopia of spherical equivalent power > -6.0 diopter in either eye

• Previous intraocular surgery

• any types of ocular pathology (e.g. media opacities or retinal lesion)

• Previous or current history of neurological problem

Related Conditions & MeSH terms

• Amblyopia

Intervention

Device:
• Dichoptic video game in an i-Pod touch device
Amblyope will wear a pair of red green goggles and play the video game with 'contrast-balanced' images displayed on the screen of an i-Pod touch device. The eye with weaker eyesight will see the image with high contrast, and the good eye will see the image with low contrast. The subject will play the game one hour per day for 6 weeks.
• Video game in an i-Pod touch device
Amblyope will wear a pair of red green goggles and play the video game with equal contrast images displayed on the screen of an i-Pod touch device. Both eyes will see the image of same contrast. The subject will play the game one hour per day for 6 weeks.

Locations

Country	Name	City	State
Hong Kong	The Hong Kong Polytechnic University	Hong Kong

Sponsors (1)

Lead Sponsor	Collaborator
The Hong Kong Polytechnic University

Country where clinical trial is conducted

Hong Kong, 

References & Publications (10)

Birch EE, Li SL, Jost RM, Morale SE, De La Cruz A, Stager D Jr, Dao L, Stager DR Sr. Binocular iPad treatment for amblyopia in preschool children. J AAPOS. 2015 Feb;19(1):6-11. doi: 10.1016/j.jaapos.2014.09.009. — View Citation

Birch EE, Subramanian V, Weakley DR. Fixation instability in anisometropic children with reduced stereopsis. J AAPOS. 2013 Jun;17(3):287-90. doi: 10.1016/j.jaapos.2013.03.011. — View Citation

Chung ST, Kumar G, Li RW, Levi DM. Characteristics of fixational eye movements in amblyopia: Limitations on fixation stability and acuity? Vision Res. 2015 Sep;114:87-99. doi: 10.1016/j.visres.2015.01.016. Epub 2015 Feb 7. — View Citation

González EG, Wong AM, Niechwiej-Szwedo E, Tarita-Nistor L, Steinbach MJ. Eye position stability in amblyopia and in normal binocular vision. Invest Ophthalmol Vis Sci. 2012 Aug 9;53(9):5386-94. doi: 10.1167/iovs.12-9941. — View Citation

Guo CX, Babu RJ, Black JM, Bobier WR, Lam CS, Dai S, Gao TY, Hess RF, Jenkins M, Jiang Y, Kowal L, Parag V, South J, Staffieri SE, Walker N, Wadham A, Thompson B; BRAVO study team. Binocular treatment of amblyopia using videogames (BRAVO): study protocol for a randomised controlled trial. Trials. 2016 Oct 18;17(1):504. — View Citation

Hess RF, Babu RJ, Clavagnier S, Black J, Bobier W, Thompson B. The iPod binocular home-based treatment for amblyopia in adults: efficacy and compliance. Clin Exp Optom. 2014 Sep;97(5):389-98. doi: 10.1111/cxo.12192. Epub 2014 Aug 18. — View Citation

Li SL, Jost RM, Morale SE, Stager DR, Dao L, Stager D, Birch EE. A binocular iPad treatment for amblyopic children. Eye (Lond). 2014 Oct;28(10):1246-53. doi: 10.1038/eye.2014.165. Epub 2014 Jul 25. — View Citation

Shaikh AG, Otero-Millan J, Kumar P, Ghasia FF. Abnormal Fixational Eye Movements in Amblyopia. PLoS One. 2016 Mar 1;11(3):e0149953. doi: 10.1371/journal.pone.0149953. eCollection 2016. — View Citation

Subramanian V, Jost RM, Birch EE. A quantitative study of fixation stability in amblyopia. Invest Ophthalmol Vis Sci. 2013 Mar 19;54(3):1998-2003. doi: 10.1167/iovs.12-11054. — View Citation

To L, Thompson B, Blum JR, Maehara G, Hess RF, Cooperstock JR. A game platform for treatment of amblyopia. IEEE Trans Neural Syst Rehabil Eng. 2011 Jun;19(3):280-9. doi: 10.1109/TNSRE.2011.2115255. Epub 2011 Feb 17. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change in fixation stability (in terms of Bivariate contour ellipse area in degree square) in the amblyopic eye after 6 weeks dichoptic video game playing in mild amblyopes	Change in fixation stability (in terms of Bivariate contour ellipse area in degree square) in the amblyopic eye after 6 weeks dichoptic video game playing in mild amblyopes. The 95% bivariate contour ellipse area will be adopted in units of degree square.	6 weeks
Secondary	Change in best corrected visual acuity (in log MAR) in the amblyopic eye after 6 weeks dichoptic video game playing in mild amblyopes	Change in best corrected visual acuity (in log MAR) in the amblyopic eye after 6 weeks dichoptic video game playing in mild amblyopes. Best corrected visual acuity will be measured in log MAR unit.	6 weeks
Secondary	Change in stereopsis (in arc sec) after 6 weeks dichoptic video game playing in mild amblyopes	Change in stereopsis (in arc sec) after 6 weeks dichoptic video game playing in mild amblyopes. The Titmus and Randot preschool stereopsis test will be used and the measurements are recorded in ' second of arc'.	6 weeks