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The following is a summary of “Choriocapillaris impairment in dry AMD: insights from swept-source OCT angiography and associations with structural biomarkers,” published in the May 2025 issue of British Journal of Ophthalmology by Overbey et al. 

Researchers conducted a retrospective study to analyze choriocapillaris flow deficit percentage (CCFD%) across different stages of dry age-related macular degeneration (AMD) using swept-source optical coherence tomography angiography (SS-OCTA).  

They analyzed 270 eyes from 182 individuals and grouped them into early (70 eyes), intermediate (121 eyes), and geographic atrophy [GA, 79 eyes] stages of dry AMD. All participants completed comprehensive assessments, including 6×6 mm macular SS-OCTA scans using the PLEX Elite 9000 system. Images were examined for subretinal drusenoid deposits [SDDs], retinal pigment epithelium [RPE] atrophy area, incomplete RPE and outer retinal atrophy [iRORA], and drusen volume in the 3 mm central region. The CCFD% was computed after compensation and binarization using Phansalkar’s method [radius = 4–15 pixels] across early treatment diabetic retinopathy study sectors. Linear mixed-effects models adjusted for age were used to evaluate correlations with AMD stages and imaging biomarkers.  

The results showed that CCFD% progressively increased with advancing stages of dry age-related macular degeneration. Intermediate AMD eyes had significantly higher CCFD% than early AMD across all examined regions (P<0.001), GA eyes demonstrated greater CCFD% than both early (P<0.001) and intermediate AMD (P<0.001), SDDs were linked to elevated CCFD% in early (P<0.01) and intermediate AMD (P<0.05) across most regions but not in GA (P>0.05). Incomplete RPE and outer retinal atrophy [iRORA] in intermediate AMD and larger RPE atrophy in GA were both associated with increased CCFD% (P<0.001).  

Investigators concluded that CCFD% increased with dry AMD severity and imaging features, supporting its potential as a clinical and research biomarker. 

Source: bjo.bmj.com/content/early/2025/05/13/bjo-2024-326416