The iPod binocular home‐based treatment for amblyopia in adults: efficacy and compliance

Abstract

Background

Occlusion therapy for amblyopia is predicated on the idea that amblyopia is primarily a disorder of monocular vision; however, there is growing evidence that patients with amblyopia have a structurally intact binocular visual system that is rendered functionally monocular due to suppression. Furthermore, we have found that a dichoptic treatment intervention designed to directly target suppression can result in clinically significant improvement in both binocular and monocular visual function in adult patients with amblyopia. The fact that monocular improvement occurs in the absence of any fellow eye occlusion suggests that amblyopia is, in part, due to chronic suppression. Previously the treatment has been administered as a psychophysical task and more recently as a video game that can be played on video goggles or an iPod device equipped with a lenticular screen.

The aim of this case‐series study of 14 amblyopes (six strabismics, six anisometropes and two mixed) ages 13 to 50 years was to investigate: 1. whether the portable video game treatment is suitable for at‐home use and 2. whether an anaglyphic version of the iPod‐based video game, which is more convenient for at‐home use, has comparable effects to the lenticular version.

Methods

The dichoptic video game treatment was conducted at home and visual functions assessed before and after treatment.

Results

We found that at‐home use for 10 to 30 hours restored simultaneous binocular perception in 13 of 14 cases along with significant improvements in acuity (0.11 ± 0.08 logMAR) and stereopsis (0.6 ± 0.5 log units). Furthermore, the anaglyph and lenticular platforms were equally effective. In addition, the iPod devices were able to record a complete and accurate picture of treatment compliance.

Conclusion

The home‐based dichoptic iPod approach represents a viable treatment for adults with amblyopia.

Key words:

• amblyopia
• children's vision
• visual acuity

Acknowledgements

This work was supported by a CIHR grant to Professor Hess (#53346) and a University of Auckland Faculty Development Research Fund grant and an HRC grant to Benjamin Thompson.

The binocular treatment described is patented by McGill University and licensed to Amblyotech (www.amblyotech.com). Robert F Hess and Benjamin Thompson are named inventors.

Additional information

Funding

CIHR

University of Auckland Faculty Development Research Fund

HRC