Purchase this article with an account.
Chang-Bing Huang, Wuli Jia, Zhong-Lin Lu; Discriminating amblyopia from myopia based on interocular inhibition. Invest. Ophthalmol. Vis. Sci. 2014;55(13):788.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Amblyopia impacts visual function via modest attenuation of signal in the amblyopic eye and markedlyelevation of interocular inhibition from the fellow eye to the amblyopic eye (Huang et al, 2011). Taking advantage of evident asymmetry in interocular inhibition in amblyopia, we developed a quick and simple procedure to discriminate amblyopia from myopia, even without optical correction in both groups.
Twenty-four amblyopic and 14 age-matched myopic subjects participated in this study. We adopted the qCSF procedure (Lesmes, et al, 2010) to measure CSF in 8 conditions: 2 eyes x 2 corrective status (with and without optical correction) x2 patching materials (untested eye patched with opaque or translucent materials). Each measurement lasted about five minutes.
We defined the ratio of the area under log CSF (AULCSF) of a tested eye between the translucent and opaque conditions as the inhibition index. The lower the inhibition index is, the greater the imbalance between the two eyes. Under the fully corrected condition, the index was significantly lower (all p<0.05) in the amblyopic eye (0.43±0.06) than in the fellow eye (1.09±0.10) of amblyopia and both eyes of the myopic subjects (0.97±0.05and 1.01±0.03); Removing optical correction led to almost the same results (0.36±0.16 vs0.93±0.19, 1.15±0.11and0.9±0.18). No significant difference was found among the two eyes of the myopic subjects and the fellow eye of amblyopic subjects, and between the corrected and uncorrected conditions. Eight-day monocular contrast detection training reduced the inhibition index by ~60% in a subgroup of amblyopic subjects. With AULCSF, cutoff spatial frequency, and inhibition index as predictors, a logistic regression has successfully discriminated amblyopia from myopia at a 100% correct rate.
Manipulating the luminance level in the fellow eye drastically changed the CSF in the amblyopic eye. The same manipulation had no significant effects on the CSF of the fellow eye in amblyopic vision, nor on the CSF of the myopic eyes. The effect may provide a simple method to discriminate amblyopia from myopia.
This PDF is available to Subscribers Only