Associations between quantitative contrast sensitivity, optical coherence tomography and progression prognostication in intermediate age-related macular degeneration.

Abstract

Purpose : To assess the association between spectral domain optical coherence tomography (SD-OCT) biomarkers, quantitative contrast sensitivity function (qCSF) metrics and progression from intermediate to late age-related macular degeneration (AMD).

Methods : This retrospective, observational study included 205 eyes of 134 patients with (1) intermediate AMD as per Beckman classification, (2) same-day OCT and qCSF test, (3) visual acuity (VA) ≥20/200 Snellen, and (4) at least 24 months of follow-up. qCSF metrics included the area under the logCSF curve (AULCSF), contrast acuity (CA), and contrast sensitivity (CS) at 1-to-18 cycles per degree (cpd). OCT scans and charts were reviewed for cuticular drusen, subretinal drusenoid deposits (SDD), hyporeflective drusen cores (hDC), refractile drusen, number of hyperreflective foci (HRF) and development of wet AMD or complete RPE and outer retinal atrophy (cRORA). Outer nuclear layer (ONL) thickness and retinal pigment epithelium (RPE) volume were semi-automatically collected using the ETDRS grid.
Generalized linear mixed-effects models assessed the association between qCSF and OCT biomarkers. Cox regression evaluated the impact of qCSF and OCT on the progression to wet AMD and cRORA. All models were nested and adjusted for age and lens opacity.

Results : Median age was 73 years (69-78) with 63% females. Mixed-effects regression revealed higher RPE volume in the central subfield and more iHRF were significantly associated with reduced AULCSF, CA and CS at 6-12 cpd. Thinner ONL in the inner ring and a greater iHRF number were associated with reduced CS at 1 and 3 cpd.
During follow-up, 35 eyes developed wet AMD (17%) and 53 progressed to cRORA (26%).
Cox regression revealed SDD, thinner inner ring ONL and CS at 1.5 cpd were associated with wet AMD. Conversely, higher inner ring RPE volume, hDC, SDD, CS at 1 cpd and a greater number of iHRF were significantly associated with progression to cRORA.

Conclusions : This study provides more structure-function analysis of OCT and qCSF metrics in intermediate AMD. Central RPE volume, parafoveal ONL thinning and iHRF demonstrate the most robust associations of CS function. Various biomarkers and CS at low spatial frequencies were associated with late AMD progression, offering valuable parameters for stratifying intermediate AMD patients in clinical settings.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.