Evaluation of Retinal Nerve Fiber Layer and Ganglion Cell Complex Thickness in Unilateral Exfoliation Syndrome Using Optical Coherence Tomography

Abstract

To evaluate retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) thickness by using optical coherence tomography in unilateral exfoliation syndrome (XFS) and to assess whether exfoliation itself is an independent risk factor for glaucomatous optic nerve damage. Thirty exfoliative eyes of unilateral XFS cases, 30 fellow eyes of unilateral exfoliation, and 30 eyes of healthy subjects were enrolled the study. Peripapillary RNFL and macular GCC thickness measurements by Cirrus HD OCT (Carl Zeiss Meditec, Dublin, CA) were performed on all subjects. RNFL thickness in superior quadrant was significantly different between groups (P=0.025) and it was thinner in XFS than healthy subjects (P=0.020). All GCC parameters except GCC thickness in inferior quadrant were significantly different between groups (P=0.110 for inferior quadrant, P<0.046 for other GCC parameters). GCC were thinner in XFS than healthy subjects except inferior and inferonasal quadrants (P=0.091, 0.051 for inferior and inferonasal quadrants, respectively, P<0.039 for other GCC parameters). Minimum GCC thickness, GCC thicknesses in superior, and inferonasal quadrants were significantly thinner in fellow eyes than healthy subjects (P=0.011, 0.013, 0.047, respectively). XFS is related with thinner RNFL and GCC even in normal intraocular pressure values, similar optic disc parameters and visual field results. XFS may be an independent risk factor for glaucomatous optic nerve damage. So, further studies are needed to evaluate whether exfoliation itself is an independent risk factor for optic nerve damage.