Purchase this article with an account.
Yi-Zhong Wang, Gui-Shuang Ying, Gina Mitzel, Yu-Guang He; Sensitivity and Specificity of Shape Discrimination Hyperacuity for Differentiating Exudative AMD from Moderate AMD. Invest. Ophthalmol. Vis. Sci. 2011;52(14):100.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Early detection of the onset of choroidal neovascularization is essential for effective treatment of exudative age-related macular degeneration (AMD). In this study, we evaluated the sensitivity and specificity of shape discrimination hyperacuity (SDH), as well as visual acuity (VA), contrast sensitivity (CS) and the Amsler grid (AG) test for differentiating exudative AMD from nonexudative moderate AMD.
Twenty-four eyes (mean E-ETDRS VA±SD: 0.19±0.12 logMAR) with high-risk (large-size drusen) moderate AMD and 9 eyes (mean VA: 0.25±0.05 logMAR) with exudative AMD were included on the basis of clinical and SD-OCT documentation and VA of 20/50 or better. Visual stimuli were distorted circular shapes generated by modulating the radius sinusoidally (mean radius = 1 deg; peak spatial frequency = 3 cyc/deg), presented in a 2-interval forced-choice staircase paradigm. SDH was obtained from radial modulation threshold estimated with a maximum likelihood fitting procedure. E-ETDRS VA test, Pelli-Robson CS test and AG test were also conducted.
The area under the receiver operating characteristic (ROC) curve for differentiating exudative AMD from moderate AMD by SDH was 0.87 (95% CI: 0.72-1.00), which was significantly higher than that of VA (0.66, CI: 0.48-0.83) and CS (0.59, CI: 0.35-0.84) (p=0.04 and 0.005, respectively). In particular, when the cutoff point for defining a test positive was selected based on optimal sensitivity with specificity 65% or higher, the sensitivity and specificity of SDH, VA, CS, as well as AG test for differentiating exudative AMD from moderate AMD were shown in the Table.
Shape discrimination hyperacuity has a high sensitivity and specificity as compared to standard visual function tests for differentiating exudative AMD from high-risk moderate AMD among patients with good visual acuity. Shape discrimination hyperacuity test may provide a useful tool to monitor the progression from moderate to exudative AMD for early treatment.
This PDF is available to Subscribers Only