Inter-Eye Difference Thresholds for Predicting an Optic Nerve Lesion in in MS: An International Study

The optic nerve is a frequent site for involvement in multiple sclerosis (MS). Current international diagnostic criteria for MS do not include the optic nerve as a lesion site despite the high prevalence of acute optic neuritis (ON). Spectral-domain optical coherence tomography (SD-OCT) detects thinning of RNFL and GCIP in MS. We sought to determine optimal thresholds for inter-eye differences in retinal nerve fiber (RNFL) and ganglion cell+inner plexiform (GCIP) layer thicknesses that are predictive of a unilateral optic nerve lesion.