Comment on the Paper by Esen et al. Entitled "Evaluation of Choroidal Vascular Changes in Patients with Multiple Sclerosis Using Enhanced Depth Imaging Optical Coherence Tomography".

thickness in optic neuritis associated with MS. Similar to Esen et al. [1] , they found a reduced average-RNFL thickness in MS eyes with optic neuritis. However, they also reported that inferiorand temporal-quadrant RNFL thickness is different between eyes with optic neuritis and control eyes. Moreover, they found a statistically significant difference in the inferior quadrant between eyes without optic neuritis and control eyes [3] . Esen et al. [1] only reported the difference between the average-RNFL thicknesses of the groups but they did not compare the quadrants in their study. As Scheel et al. [2] , we think that RNFL can be used as a marker of MS damage in the optic pathway and white matter and wonder whether there is a significant difference between the control, MS-with-optic-neuritis and MS-without-optic-neuritis groups in their study. We suppose that this comparison will improve our understanding of the application of RNFL measurements in patients with MS. Dear Editor We read the article by Esen et al. [1] entitled ‘Evaluation of choroidal vascular changes in patients with multiple sclerosis using enhanced depth imaging optical coherence tomography’ with great interest. The authors evaluated the choroidal thickness changes in patients with multiple sclerosis (MS) using optical coherence tomography. They found that choroidal structural and retinal nerve fiber layer (RNFL) changes can be seen in the course of MS. We congratulate the authors for their study and would like to make a contribution. Scheel et al. [2] investigated the association of RNFL with white matter damage assessed by diffusion tensor imaging. They reported that there was a significant correlation between RNFL and fractional anisotropy inside the optic radiation, central corpus callosum and remainder of the white matter. They suggested that RNFL can be used as a marker of white matter damage in MS. Chatziralli et al. [3] evaluated RNFL Received: November 8, 2015 Accepted: November 26, 2015 Published online: January 5, 2016