The impact of optic disk morphological characteristics on peripapillary retinal nerve fiber layer thickness in non-glaucomatous subjects with high myopia.

BACKGROUND

To analyze peripapillary retinal nerve fiber layer (pRNFL) thickness (pRNFLT) alterations in non-glaucomatous eyes with high myopia (HM), and to describe its relationship with some optic disk (OD) morphologic features.

METHODS

A cross-sectional case-control study includes 185 Caucasian subjects with HM and 122 healthy controls. Results of the pRNFLT analysis provided by optical coherence tomography were compared between the HM and control group, and the effects of some morphological features of OD, including tilt, OD radius, and peripapillary chorioretinal atrophy (pCRA) extension, on pRNFLT analysis were investigated.

RESULTS

The mean pRNFL of the HM group was significantly thinner than the control group in the inferior (p <0.001), superior (p <0.001), and nasal (p = 0.001) quadrants. In the HM group, the superior quadrant pRNFL was significantly thinner in the tilted OD subgroup compared to the non-tilted OD subgroup (p <0.001). The mean pRNFLT was negatively correlated with pCRA extension in the inferior (r =-0.209 and p = 0.020), superior (r =-0.308 and p <0.001), and nasal (r =-0.235 and p = 0.008) quadrants.

CONCLUSIONS

In non-glaucomatous Caucasian subjects with HM, pRNFL is thinner compared to controls in the inferior, superior, and nasal quadrants, and this thinning is negatively correlated with pCRA extension. Superior quadrant pRNFL is also thinner in tilted OD than non-tilted OD. The morphological characteristics of OD in non-glaucomatous eyes with HM are closely associated with the results of pRNFLT analysis.