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The following is a summary of “Longitudinal OCTA vessel density loss in macula and optic nerve head in healthy, glaucoma suspect and established glaucoma eyes,” published in the October 2024 issue of Ophthalmology by Wu et al.
Researchers conducted a retrospective study to assess the longitudinal changes in macular and optic nerve head (ONH) microvascular parameters measured by optical coherence tomography angiography (OCTA) in healthy, glaucoma suspect (GS) and primary open-angle glaucoma eyes (POAG).
They included healthy, GS and POAG eyes from the Diagnostic Innovations in Glaucoma Study with follow-up of at least 2 years and 4 visits of macular and ONH OCTA imaging. Changes in whole-image vessel density (wiVD) for the macula and whole-image capillary density (wiCD) for the ONH were calculated for each diagnostic group using joint mixed-effect modeling. Differences in the rates of change of wiVD and wiCD among the diagnoses were examined through pairwise comparisons. Additionally, the relationships between baseline 24-2 visual field (VF) mean deviation (MD) and the rates of change in wiVD and wiCD were evaluated for POAG eyes.
The results showed that there were 36, 57, and 79 eyes (25, 38, and 50 subjects) in the healthy GS and POAG groups, respectively. Rates of wiVD loss ranged from -0.72 to -0.92% per year, and wiCD loss ranged from -0.28 to -0.66% per year, with all groups showing rates different from zero (P <0.05). The rates of wiCD loss varied significantly across all diagnosis groups (P <0.001), while wiVD change rates did not differ when comparing healthy eyes to GS eyes (P =0.167). Baseline VF MD demonstrated a significant but modest correlation with the rates of both wiVD and wiCD loss (P <0.05), with a slightly stronger correlation observed for wiCD change rates (R2 =0.27 vs. R2 =0.16).
They concluded that glaucoma exhibited earlier microvascular loss in the ONH than in the macula, indicating that ONH vessel density loss may serve as a significant early biomarker for glaucoma progression.
Source: bjo.bmj.com/content/early/2024/10/28/bjo-2024-325746
