Clinical profile, imaging features and short term visual outcomes of Indian optic neuritis patients with and without seromarkers for myelin oligodendrocyte glycoprotein and neuromyelitis optica

Abstract

Purpose: To analyze clinical profile, imaging features, and short-term visual outcomes of optic neuritis patients in Indian population with and without seromarkers for myelin oligodendrocyte glycoprotein (MOG)/neuromyelitis optica (NMO). Methods: Electronic medical records of 203 optic neuritis patients who presented between June 2018 and December 2019 to the Neuro-ophthalmology services of a tertiary care center in India were retrospectively analyzed. Results: Of 203 patients, 57 patients (28.08%) were positive for MOG-antibody and 20 patients (9.85%) were positive for NMO antibody. 114 patients (56.16%) were double-negative (negative for both antibodies) and 12 patients (5.91%) were diagnosed as multiple sclerosis (MS). None of the patients had both antibodies. Mean age of presentation was 31.29 ± 1.035 years. There was female preponderance in NMO-optic neuritis (NMO-ON) and MS-optic neuritis (MS-ON) groups (1:5). Mean vision on presentation was worse (logMAR 1.570 ± 0.863) in NMO-ON group. The mean visual acuity showed statistically significant recovery (logMAR 0.338 ± 0.639) in the final follow-up in MOG-optic neuritis (MOG-ON) group. Multivariate logistic regression analysis revealed poor visual outcome in patients presenting with retrobulbar neuritis, optic disc pallor, bilateral sequential optic nerve involvement, and with positive NMO antibody. Optic neuritis patients presenting with disc edema associated with pain and positive for MOG antibody were found to have a better visual outcome. Conclusion: In this Indian optic neuritis cohort, the prevalence of MOG-ON was higher than NMO-ON. MOG-ON had a better visual outcome than NMO-ON. The incidence of MS-ON was less compared to the western literature. A significant number of patients (114 patients, 56.16%) were double negative for both seromarkers and yet had presented with optic neuritis with no clinical or imaging features suggestive of MS/MOG associated disease (MOG AD)/NMO spectrum disorder (NMO SD).

A 10-Year Single-Center Study of the Clinical Characteristics of Optic Neuritis-Related NMOSD, MS, and Double Seronegative Optic Neuritis, Together with Factors Predicting Visual Outcomes

“…The impact of gender on visual outcome seems to vary substantially in the literature. Guo et al proposed that females with NMOSD-ON attained a significantly better therapeutic response [ 4 ]; however, some researchers have found contrary results, reporting that there was no association between gender and visual outcome among NMOSD, MS or double seronegative optic neuritis, which was in concordance with our conclusion that gender had no bearing on visual improvement in the three optic neuritis groups [ 9 , 10 , 12 ].…”

“…Poor baseline visual acuity at nadir has been identified as a significant predictor of poor outcomes in several studies of both seronegative-ON and NMOSD-ON [ 10 , 12 , 23 , 24 ]. However, the current study found that it lost statistical significance in the multivariable logistic model.…”

“…Ishikawa et al found better final vision in NMOSD-ON with disc swelling at the initial visit [ 30 ]; however, its statistical significance was lost at the final regression model in predicting the treatment outcomes of all categories (including MOG-ON, NMOSD-ON, and DN-ON). With regard to Asian populations, an Indian study noted that having initial disc swelling at presentation yielded a 4.5 times higher odds ratio of attaining a final VA of greater than 6/18 [ 12 ]. Some researchers, however [ 9 , 10 , 30 ], have contradicted this result, concluding that disc morphology had no impact on visual outcome.…”

“…The prompt administration of intravenous methylprednisolone (IVMP) has been found to improve the chances of favorable visual acuity in both NMOSD- and MOG-related optic neuritis patients [ 5 , 7 , 8 ], and baseline visual status has been identified as a factor that can affect visual outcomes after treatment [ 9 , 10 , 11 ]. Regarding the impact of disc morphology on visual outcomes, Ambika et al stated that patients with a swelling disc appearance at the initial visit had an approximately 4.5-fold better chance of achieving a final visual acuity of greater than 6/18 [ 12 ]. Previous studies of Thai populations in the literature have evaluated some predictors affecting visual prognosis using Snellen VA; however, there is limited information on which factors influence visual recovery in terms of improvement in the number of Snellen lines or the logarithm of minimal angle resolution units [ 10 , 11 ].…”

MOG antibody-associated optic neuritis

“…The presence of severe optic disc swelling and peripapillary haemorrhage in the setting of ON is highly suggestive of MOG-ON. Optic disc swelling visible on fundoscopy has been reported in 45-92% of cases of MOG-ON across various international cohorts [22,[43][44][45][47][48][49][50][51][52], and is an important diagnostic clue when assessing patients with ON. This is far more common than the frequencies reported in AQP4-ON (7-52%) [44,48,50,51], and MS-ON (11-14%) [49,51].…”