Posters

Retinal nerve fiber layer thickness in patients with large optic discs using optical coherence tomography and confocal scanning laser ophthalmoscopy

Poster Details

First Author: E.Baser TURKEY

Co Author(s):    S. Kilic   H. Mayali   G. Seymenoglu              

Abstract Details

Purpose:

Large optic discs are suspected to be more susceptible to glaucomatous damage, while they are reported to have greater retinal nerve fiber layer (RNFL) thickness compared to normals. The purpose of this study is to investigate RNFL thickness of patients with large optic discs using two different devices, and to search correlations between optic disc area (DA) and some other ocular parameters.

Setting:

Celal Bayar University School of Medicine Department of Ophthalmology, Glaucoma Section.

Methods:

Patients with glaucoma or glaucoma suspects with large DA who were followed in our department were included. Patients’ DA and cup/disc (C/D) ratio were determined with confocal scanning laser ophthalmoscopy (CSLO) and RNFL thickness was measured with both CSLO and optical coherence tomography (OCT). Central corneal thickness (CCT) was measured with optical pachymetry. RNFL thickness measurements determined by two different devices were compared with each other. Correlations between DA, C/D ratio, CCT and RNFL thicknesses were investigated.

Results:

The study included 137 eyes of 101 patients with a mean age of 55.9. The mean spherical equivalent refraction was -0.36 D, mean DA was 2.74 mm and mean CCT was 547 microns. Mean RNFL thickness was 189 microns with CSLO and 95 microns with OCT, which was significantly different (p=0.001). Statistical analysis showed no correlations between DA and refraction (r:0.147), DA and CCT (r:0.079), DA and C/D (r:0.166), DA and RNFL with CSLO (r:0.013) and DA with RNFL with OCT (r:0.067).

Conclusions:

Measurements of RNFL as determined by CSLO and OCT should not be used interchangeably. Since there appears to be no correlations between DA, refraction, CCT and RNFL thicknes in eyes with large optic discs, we conclude that optic disc size should be considered as a separate risk factor for glaucoma.

Financial Disclosure:

NONE