Combined Fundus Autofluorescence and Near Infrared Reflectance as Prognostic Biomarkers for Visual Acuity in Foveal-Sparing Geographic Atrophy

Abstract

During the review period eyes with foveal-sparing GA were likely to maintain the baseline BCVA. There was no linear correlation of BCVA with foveal-sparing size. Yet, BCVA was worse if the spared foveal area was <1.5 mm2 or if the bridge was smaller than 400 μm in width. These findings add to the understanding of the natural history of foveal-sparing GA and may support future clinical trial designs.

Percentage of Foveal versus Total Macular Geographic Atrophy as a Predictor of Visual Acuity in Age-related Macular Degeneration

“…Foveal sparing status has been shown to have a stronger correlation with VA than total GA size, however, it does not quantify the extent to which the foveal area is affected nor the worsening of VA over time since it only measures presence or absence of geographic atrophy in the anatomic foveola centralis 8, 15, 16 . A recent investigation of the associations of VA with total GA size as well as foveal sparing status in 65 eyes found no relationship between VA and total GA size as well as foveal island size 18 . The same group also evaluated the width of the bridge - defined as the minimal linear dimension of intact RPE located within the residual foveal island - and only found a suggestion of a positive relationship in the range of 300 to 550 μm of bridge width and no relationship at all outside of this range leading to the conclusion that this measurement might not be an ideal outcome parameter for GA clinical trials.…”

Multimodal Imaging of Nonneovascular Age-Related Macular Degeneration

“…These results have been replicated to some extent in subsequent reports. 36,137,140,141 Additionally, the extent of hyperautofluorescence surrounding atrophic lesions, defined as the rim-area focal hyperfluorescence or the convex hull (the convex polygon outlining the hyperautofluorescent area surrounding the lesion), have been positively correlated with lesion growth rates (Fig. 7).…”

“…36 137 In another report by Sunness et al, 138 eyes with baseline unifocal lesions progressing to multifocal, horseshoe, ring, or solid configurations had greater GA progression rates than eyes with a stable configuration. 138 Qualitative FAF patterns of the hyperautofluorescence surrounding the GA lesions have been shown to correlate with growth rates of GA. 36,137,[139][140][141] The FAF in AMD (FAM) study classified GA according to the associated or adjacent hyperautofluorescent patterns, including none, focal, banded, patchy, or diffuse, with diffuse patterns further categorized as reticular, branching, fine granular, fine granular with peripheral punctate spots, or trickling (Fig. 7).…”

Microperimetry for geographic atrophy secondary to age-related macular degeneration

“…Metrics of visual function, including BCVA, low-luminance visual acuity, reading speed, and patient-reported outcomes, provide valuable information about how GA affects patients on a daily basis. 44 Often, however, BCVA does not correlate with visual dysfunction in patients with GA. 57 Patients with foveal-sparing lesions and associated paracentral scotomas can experience apparent preservation of central vision based on a high-contrast single-letters test such as BCVA even while parafoveal lesions enlarge over time 23,48 ; however, these patients may experience other visual function deficits during activities of everyday living, such as a blurred or distorted visual field or changes in reading speed. 57 Microperimetry is a psychophysical visual function test used to spatially map retinal sensitivity or the level of response of the retina to light stimuli (assuming that the posterior visual pathway is normal and subjects can perform the test).…”