Using Microperimetry and Low-Luminance Visual Acuity to Detect the Onset of Late Age-Related Macular Degeneration

Abstract

To evaluate the performance of microperimetry and low-luminance visual acuity for detecting late age-related macular degeneration (AMD) onset.Methods: Two hundred ninety-two individuals with bilateral large drusen in the Laser Intervention in the Early Stages of AMD study underwent best-corrected visual acuity, lowluminance visual acuity, and microperimetry testing as well as multimodal imaging to detect late (neovascular or atrophic) AMD onset. The performance of the change in the measurement from baseline of each of visual function test for detecting late AMD onset was compared.Results: The area under the receiver operating characteristic curve for detecting neovascular and atrophic AMD onset was not significantly different for low-luminance visual acuity (area under the receiver operating characteristic curve = 0.71 and 0.56, respectively) and microperimetry (area under the receiver operating characteristic curve = 0.82 and 0.62, respectively) compared with best-corrected visual acuity (area under the receiver operating characteristic curve = 0.57 and 0.56, respectively; P $ 0.126 for all). There was also only a fair degree of agreement between the three visual function measures for detecting the onset of neovascular and atrophic AMD (k $ 0.24).Conclusion: Microperimetry, low-luminance visual acuity, and best-corrected visual acuity demonstrate limited performance for detecting the earliest onset of late AMD. It remains to be established whether they perform better than current methods designed to enable self-detection of neovascular AMD onset, such as Amsler grid testing.RETINA 41:1094-1101, 2021N eovascular age-related macular degeneration (nAMD) often develops spontaneously in at-risk individuals with the asymptomatic, early signs of AMD. It is now well recognized that long-term visual acuity outcomes of antivascular endothelial growth factor treatments are highly dependent on presenting visual acuity. [1][2][3] Unfortunately, those that are symptomatic at onset of nAMD present with loss of vision at a level that may not be recoverable despite treatment with the current generation of biologicals.A major barrier for the early detection of nAMD is the lack of sufficiently accurate and appropriate self-monitoring tools. Although conventional Amsler grid testing has a sensitivity of 78% for detecting nAMD with relatively severe visual acuity loss, 4 it can only detect one-third of nAMD eyes with a median pretreatment visual acuity of 20/50. 5 Other visual function tests such as preferential hyperacuity perimetry have been developed in an attempt to overcome this important limitation. A randomized trial demonstrated those randomized to self-monitoring with preferential hyperacuity perimetry led to a median of 4 letters improvement in visual acuity at the time nAMD was first detected compared with those randomized to standard care 1094

Functional Correlates of Outer Retina Remodeling in Intermediate Age-Related Macular Degeneration Using Microperimetry

“…Recent evidence has shown that microperimetric sensitivity and low luminance deficits are poor predictors for AMD progression by themselves when analyzing patients with large drusen, especially when comparing these findings with the presence of pigmentary on fundoscopy. 63 , 64 This may be consistent with making a distinction between growth and regression as two different parts of the drusen life-cycle. Pigmentary changes seen on fundus examination may result from profound RPE–basal lamina alterations, with a loss of overlying photoreceptor bands and associated hypertransmission on OCT B-scans, 46 possibly coexisting with some degree of fading or regression of drusen elements.…”

Targeted High-Density Microperimetry Testing of Nascent Geographic Atrophy in Age-Related Macular Degeneration

“…Individuals in the LEAD Study underwent microperimetry using a standard central 6° radius grid centered on the fovea (based on the preferred retinal locus determined at the start of the examination), consisting of 37 points located at 0°, 1°, 2.33°, 4° and 6° from the fovea. 22 , 23 This stimulus grid is shown in Figure 1 , and all participants performed 2 tests in each eye at every visit. Individuals in the prospective observational study underwent high-density targeted microperimetry testing with an isotropic stimulus pattern also consisting of 37 points that sampled a 1.75° radius (or approximately 1000 μm diameter) region, with an interstimulus spacing of 0.5°.…”

Biomarkers for the Progression of Intermediate Age-Related Macular Degeneration

“…Compared with controls, patients with iAMD have significant deficits in LLVA ( p < 0.05) [ 101 ]. Nevertheless, research examining LLVA along with microperimetry in the same cohort has suggested that LLVA has limited sensitivity for detecting progression to late AMD [ 105 , 106 ].…”