Objective:

To compare conventional nAMD subtypes with a classification based on drusen and pachychoroid features for predicting long-term visual and atrophic outcomes.

Approach:

• Study design: Retrospective cohort study of 120 treatment-naïve eyes followed for at least six years at a single center in Japan.
• Treatment and classification: All eyes received three anti-VEGF loading doses followed by pro re nata treatment. Researchers classified eyes using conventional categories and a newer system: drusen, pachychoroid, mixed, and other.
• Outcomes: The study assessed maintenance of best-corrected visual acuity (BCVA) and the prevalence of retinal pigment epithelial and outer retinal atrophy (RORA) and complete RORA (cRORA).

Key Findings:

• Overall, 71% of eyes maintained BCVA, defined as losing fewer than 15 ETDRS letters.
• Visual retention did not differ significantly among typical nAMD, PCV, and RAP under conventional classification.
• With the newer classification, 82% of pachychoroid-type eyes maintained vision, compared with 38% of drusen-type eyes.
• BCVA worsened when RORA or cRORA emerged: mean logMAR changed from 0.10 to 0.35 at RORA onset and from 0.36 to 0.82 at cRORA onset.
• At six years, cRORA prevalence was 61.5% in the drusen group and 27.2% in the pachychoroid group; final cRORA prevalence differed significantly across the newer phenotypes.
• Conventional subtypes showed no significant differences in RORA or cRORA prevalence.

Interpretation:

The study authors suggest that classification by drusen and pachychoroid features may distinguish long-term risks of vision loss and atrophy more clearly than conventional nAMD categories. They propose that differences in underlying disease biology may contribute to the observed contrast.

Limitations:

• The study was retrospective and conducted at a single Japanese center.
• Some subgroups, particularly RAP, were small.
• Different anti-VEGF agents were used during the study period.
• The authors state that prospective studies are needed to establish causality.

Conclusion:

The findings suggest that drusen- and pachychoroid-based phenotyping may provide prognostic information about long-term atrophy and vision outcomes; the authors call for prospective studies.