Abstract
Purpose :
Previous studies have shown that amblyopic patients had structurally intact binocular vision that manifested functionally monocular by suppression and plenty of evidences pointed out that binocular therapy might be effective for adults. We used a novel dichoptic paradigm Implemented in augmented-reality (AR) platform to investigate the efficacy of the novel contrast-rebalance paradigm of daily take-home activities in restoring visual function and stereopsis of amblyopic eyes in adults.
Methods :
15 adults with monocular anisometropic amblyopia who failed in occlusion therapy were enrolled in our study. We set up a contrast-rebalance paradigm implemented in AR platform that was composed of a dual camera system with a head-mounted display and an image-processing system. Therefore, the real-world information from the cameras could be modulated and presented separately for two eyes. The original images and contrast-modulated, partially deprived images were presented in amblyopic eyes and fellow eyes respectively. Each subject was instructed to perform daily activity while wearing this AR platform at home for at least 1.5 hour a day for at least 6 weeks. Visual acuity, randot test were performed before training, after training and 2 months training. Dichoptic global motion coherence paradigm and binocular phase combination paradigm were used to quantify inter-ocular suppression. Functional magnetic resonance (fMRI) was used to investigate the functional alterations in LGN after training.
Results :
The monocular acuity significantly improved in 13 patients and the stereopsis of all patients was reestablished after 6-week contrast-rebalance AR training. The degree of suppression was gradually reduced and the performance of two eyes was almost equal to each other after training. Significantly improved visual acuity, stereopsis and balanced interocular suppression still maintained at 2 months follow-up point after 6-week binocular training. FMRI showed significantly increased bold signal in LGN (especially in P layer) and V1.
Conclusions :
The daily-activity-based dichoptic training with AR platform can reduce suppression and restore visual acuity as well as stereoscopic function in adult amblyopia beyond the critical period. This provides a promising treatment for adult amblyopia.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.