# Interpupillary Distance and Peripapillary Myopic Changes: A Pilot Study in a Glaucomatous Cohort

## TL;DR

This study investigates whether interpupillary distance affects myopic changes around the optic nerve in glaucoma patients, finding no significant link.

## Contribution

The study is the first to explore the relationship between interpupillary distance and peripapillary myopic changes in a glaucomatous cohort.

## Key findings

- Interpupillary distance showed no significant correlation with optic disc ovality or gamma peripapillary atrophy width.
- Axial length was strongly correlated with optic disc ovality and gamma peripapillary atrophy.
- Biomechanical forces from interpupillary distance do not appear to influence optic nerve head remodeling in myopia.

## Abstract

Background/Objectives: Myopia is associated with peripapillary changes, namely, gamma peripapillary atrophy (γPPA) and optic disc ovalization, estimated by the ovality index (OI). These changes have been suggested to be promoted by adduction. Recent studies highlight that near reading significantly contributes to the development and progression of myopia and that the interpupillary distance (IPD) influences vergence amplitudes. While both adduction and convergence are involved during near reading, a potential link between IPD and myopic peripapillary changes has not yet been explored. We, therefore, sought to determine whether IPD is related to the OI or γPPA width. Methods: In this monocentric cross-sectional study, 100 eyes from 100 adults (mean age of 62.6 ± 13.7 years) were analyzed. Axial length (AL), refractive error, and IPD were recorded. The OI and γPPA width were assessed using spectral-domain Optical Coherence Tomography. Pearson correlations and multivariable linear regressions were performed, adjusting for age, gender, and myopia status. Results: IPD showed no significant correlation with the OI (r = 0.001; p = 0.989) or γPPA (r = −0.028; p = 0.789). A weak, non-significant correlation was found between IPD and AL (p = 0.059). In contrast, AL was strongly correlated with both a lower OI and wider γPPA (p < 0.001). Conclusions: These findings suggest that IPD-related biomechanical forces do not influence optic nerve head (ONH) shape or γPPA. Axial elongation remains the key driver of myopic ONH remodeling.