Abstract
Purpose :
To investigate the associations between the distribution of the retinal nerve fiber layer, the retinal vascular topography and disc size in healthy myopic eyes.
Methods :
A total of 105 healthy myopic eyes from 105 subjects were included. Disc imaging was performed with both SD OCT and HRT 2 in each subject. The middle point of the intersections of the most temporal major retinal blood vessels (including superior artery, superior vein, inferior artery and inferior vein) and the 3.46 mm circle were determined. Subsequently, the retinal vessel angle was calculated. We divided subjects into two groups (small disc group [n=42] and control group [n=63]) using an HRT-measured disc size of 1.5 mm2 as a reference point. The RNFL thickness peak angle around the optic disc was calculated. Comparisons of the RNFL thickness peak angle and the retinal vessel angle were performed between the two groups by independant t test.
Results :
Both the retinal vessel angle and the RNFL thickness peak angle were significantly and independently associated with disc area (β=0.35 and β=0.25, respectively, all p<0.001), after adjustment of other covariants. We observed significant temporal shifting of the retinal vessel angles and the RNFL thickness peaks in the small disc group compared with the controls.
Conclusions :
Retinal vessel angle and the RNFL thickness peak angle were independently associated with various disc parameters. Temporal shifting of the retinal nerve fiber layer thickness profile and the retinal vascular topography were associated with smaller disc size in healthy myopic eyes. As this phenomenon may lead to false positive results in OCT-based RNFL thickness maps, results from our study may help prevent misdiagnosis of glaucoma and improve the sensitivity and specificity of glaucoma detection.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.