Visual Function Metrics in Early and Intermediate Dry Age-related Macular Degeneration for Use as Clinical Trial Endpoints

Abstract

Purpose To evaluate and quantify visual function metrics to be used as predictors of AMD progression and visual acuity (VA) loss in patients with early and intermediate AMD. Design Baseline data of observational, cross-sectional, prospective study. Methods 101 patients were enrolled at Duke Eye Center: 80 patients with AMD age-related eye disease study (AREDS) stage 2 (N=33) and stage 3 (N=47) and 21 age-matched, normal controls. A dilated retinal examination, macular pigment optical density measurements, and several functional assessments: best-corrected VA, mesopic microperimety with eye tracking (MAIA), dark adaptometry (AdaptDx), low luminance VA (LLVA) (standard using log 2.0 neutral density filter and computerized method) and cone contrast test (CCT) (Innova Systems Inc) were performed. Low luminance deficit (LLD) was defined as the difference in numbers of letters read at standard vs. low luminance. Group comparisons were performed to evaluate differences between the control and the AREDS 2 and AREDS 3 groups using two-sided significance tests. Results Functional measures that significantly distinguished between normal and AREDS3 were standard and computerized (0.5 cd/m2) LLVA, percent reduced threshold and average threshold on microperimetry, CCTs, and rod intercept on dark adaptation (p < 0.05). The AREDS 3 group demonstrated deficits in microperimetry reduced threshhold, computerized LLD2 and dark adaptation rod intercept (p < 0.05) relative to AREDS 2. Conclusions and Relevance Our study suggests that LLVA, MAIA microperimetry, CCT and dark adaptation may serve as functional measures of AMD progression.

Cones in ageing and harsh environments: the neural economy hypothesis

“…By studying mesopic vision to include both rod and cone responses, it becomes clear that rods play a role in colour vision, and not just light adaptation. The differing characteristics of rods vs cones for light level, wavelength, retinal eccentricity, and temporal and spatial aspects of vision result in functional differences between controls and patients with AMD for scotopic, mesopic, and photopic mechanisms, along with adaptation, colour contrast, acuity, etc …”

“…The differing characteristics of rods vs cones for light level, wavelength, retinal eccentricity, and temporal and spatial aspects of vision result in functional differences between controls and patients with AMD for scotopic, mesopic, and photopic mechanisms, along with adaptation, colour contrast, acuity, etc. 95,96 In addition to retinal remodelling that occurs with loss of neurons, 84 there is the potential for binocular summation or inhibition, with differences due to binocular disparity, spatial frequency, and eccentricity. 97 In patients with geographic atrophy and AMD, potential vision is not accurately assessed by limiting measurements only to initial ones.…”

Evidence for the Detection of Subclinical Retinal Involvement in Systemic Lupus Erythematosus and Sjögren Syndrome: A Potential Association with Therapies

“…However, the wide spectrum of the kidney involvement in SLE patients needs a larger population to better explore the potential correlation between renal function and ophthalmological findings. HCQ is cleared to a large degree by the kidney, and as such renal disease may increase the circulating level of the drug and the risk of toxicity [28, 29]. Therefore, patients with renal disease might have unpredictably high blood drug levels and a higher risk of toxicity, although there are no specific data to confirm this.…”

The Relationship Between Central Drusen Volume and Low-Luminance Deficit in Age-Related Macular Degeneration

“…The same group later reported that baseline LLD was not correlated with 12-month changes in VA measures or microperimetric sensitivity, although changes in VA were minimal over this period. 15 Cocce et al 3 found that LLD was significantly different between early and intermediate AMD patients, but only on computerized assessment. Although the utility of LLD in the classification of AMD remains unclear, it is likely still useful as a practical measure of patient functionality.…”

“…Visual acuity (VA), the most commonly used measure of visual function, is often unaffected in early and intermediate stage disease. 3 To better stratify disease severity and risk of progression to more advanced disease, there is a need to identify additional markers for AMD progression and to understand the relationships between these markers.…”