Journal of Clinical and Experimental Ophthalmology
Open Access

Abstract

Improvement of Contrast Sensitivity in Adults with Amblyopia through Dichoptic Attention Task Training

Gabriela Acevedo Munares, Ismet Joan Uner and Chuan Hou*

Aim: Attention deficits are revealed in amblyopic vision. It has been reported that selective visual attention is allocated preferentially toward the non-amblyopic fellow eye in adults with amblyopia. In this study, we examined whether training with dichoptic attention tasks, which is expected to improve selective visual attention to the amblyopic eye, improves contrast sensitivity in adults with amblyopia.

Methods: We used training stimuli, which included tasks that required significant attentional efforts from the amblyopic eye. Through a mirror stereoscope, participants were instructed to quickly search and count highly visible targets presented in the amblyopic eye, while simultaneously being presented with distractors in the fellow eye. Thirteen adults with amblyopia (six anisometropic and seven strabismic) between 22 and 66 years old participated in the study. Trainings were about two visits per week and two hours per visit for two months. Contrast response function and contrast sensitivity (1/contrast threshold, defined as the contrast at 75% correct orientation responses) in the amblyopic eye were measured with psychophysical procedures and compared before and after the training.

Results: Contrast response function and contrast sensitivity in the amblyopic eye improved for 10 of 12 participants after training (one strabismic amblyope withdrawn from the study). The group average of contrast sensitivity after the training was significantly higher than that before the training (p<0.01). Contrast sensitivity improved an average of 31.73% across all participants, which was correlated with the improvement of selective visual attention to the amblyopic eye (rho=0.55, p=0.04). There was no significant difference in contrast sensitivity improvement between subgroups of anisometropic and strabismic amblyopia (p=0.1495).

Conclusion: Amblyopic training with a dichoptic approach, incorporating attention demand tasks in the amblyopic eye, might be an effective way of treating amblyopia.

Published Date: 2023-09-29; Received Date: 2023-08-28