Optical coherence tomography (OCT) measurements of ganglion cell + inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) thicknesses are associated with visual function (VF) and disability in multiple sclerosis (MS). However, the value of measuring Bruch membrane opening–minimum rim width (BMO-MRW) thickness in MS remains unclear.
Sixty-eight patients with MS and 22 healthy controls (HCs) underwent spectral domain OCT, 100%-contrast visual acuity (VA), 2.5%- and 1.25%-contrast letter acuity (LA), and Expanded Disability Status Scale (EDSS) testing. Mixed-effects linear regression models, accounting for within-subject, intereye correlations, were used to assess relationships.
The MS cohort exhibited significantly lower BMO-MRW (P = 0.01), pRNFL at 3.7-, 4.1-, and 4.7-mm diameters surrounding the optic disc (P < 0.001 for all), and GCIPL (P < 0.001) thicknesses than HCs. BMO-MRW thickness was associated with 100%-VA (P < 0.001, R2 = 0.08), 2.5%-LA (P < 0.001; R2 = 0.13), and 1.25%-LA (P = 0.002; R2 = 0.11). All measured pRNFL thicknesses were associated with high- and low-contrast VF (all: P < 0.001). GCIPL thickness was more strongly associated with 100%-VA (P < 0.001; R2 = 0.23), 2.5%-LA (P < 0.001; R2 = 0.27), and 1.25%-LA (P < 0.001; R2 = 0.21) than the other OCT measures assessed. All OCT measures were significantly, but weakly, associated with EDSS scores.
BMO-MRW and pRNFL thicknesses are reduced and associated with VF and disability in MS, but GCIPL thickness is a stronger marker of visual impairment. Our findings corroborate the utility of OCT in providing valuable information regarding the MS disease process.
Department of Neurology (JN, AR, NG, AA, EO, PAC, and SS), Johns Hopkins University School of Medicine, Baltimore, Maryland; Departments of Neurology (LJB and SLG), Population Health (LJB and SLG), and Ophthalmology (LJB and SLG), New York University School of Medicine, New York, New York; Departments of Neurology (EMF and TF) and Ophthalmology (EMF and TF), Dell Medical School, University of Texas at Austin, Austin, Texas; and Department of Biostatistics (CC), Johns Hopkins University, Baltimore, Maryland.
Address correspondence to Shiv Saidha, MBBCh, MD, MRCPI, Neurology Division of Neuroimmunology and Neurological Infections, Johns Hopkins Hospital, 600N. Wolfe Street, Baltimore, MD 21287; E-mail: ssaidha2@jhmi.edu
This study was funded by Race to Erase MS (grant number not applicable [to S.S.]); National Institute of Health (grant number 5R01NS082347-02 [to P.A.C.]); National Multiple Sclerosis Society (grant number RG-1606-08768 [to S.S.]); and Walters Foundation (grant number not applicable [to E.M.F.]).
The authors report no conflicts of interest.
