Clinical Progression of Optic Disc Suspects: Structural Changes and Functional Outcomes

Background:Optic disc suspects with structural abnormalities represent a heterogeneous group at variable risk of developing glaucomatous functional loss. The relationship between structural damage and visual field deterioration remains complex and not fully predictable.

Objective:To evaluate the association between structural changes of the optic nerve head and functional visual outcomes in glaucoma suspects, and to identify factors influencing disease progression.

Methods:A systematic review and meta-analysis were conducted including studies published between 1995 and 2024 from PubMed, Scopus, Web of Science, and Embase. Eligible studies involved human subjects classified as glaucoma suspects with structural abnormalities but without baseline visual field defects.

Results:A total of 42 studies (18,732 eyes) were included, with a mean follow-up of 6.8 ± 2.9 years. The pooled incidence of functional conversion was 21.6% (95% CI: 18.9–24.3%), increasing with longer follow-up. Progressive structural changes were the strongest predictors of functional loss (HR: 18.4; 95% CI: 12.7–26.1; p < 0.001). Moderate to strong correlations were observed between retinal nerve fibre layer (RNFL) thickness and visual field indices (r = 0.52–0.74). However, 38–45% of eyes with structural progression did not develop functional loss, while 12–18% showed functional decline without detectable structural change. RNFL thinning rate demonstrated high predictive accuracy (AUC: 0.84–0.91).

Conclusion: Structural abnormalities significantly increase the risk of functional deterioration in glaucoma suspects, but progression is not universal. Longitudinal structural monitoring, particularly RNFL thinning rates, provides superior predictive value over baseline measurements.