Clinical characteristics of optic neuritis phenotypes in a 3-year follow-up Chinese cohort

Comparison of macular changes according to the etiology of optic neuritis: a cross-sectional study

AIM

To compare the macular structure including foveal thickness among patients with optic neuritis (ON) according to the etiology and to investigate the possible correlation between structural and visual outcomes.

METHODS

In this retrospective cross-sectional study, the clinical data of patients with aquaporin-4 immunoglobulin G-related ON (AQP4 group, 40 eyes), myelin oligodendrocyte glycoprotein IgG-related ON (MOG group, 31 eyes), and multiple sclerosis-related ON (MS group, 24 eyes) were obtained. The retinal thickness of the foveal, parafoveal and perifoveal regions were measured. Visual acuity (VA), visual field index and mean deviation were measured as visual outcomes.

RESULTS

The AQP4 group showed a significantly thinner fovea (226.4±13.4 µm) relative to the MOG (236.8±14.0 µm, P=0.015) and MS (238.9±14.3 µm, P=0.007) groups. The thickness in the parafoveal area also was thinner in the AQP4 group, though the difference in perifoveal retinal thickness was not significant. Foveal thickness was correlated with VA in the AQP4 group (coefficient ρ=-0.418, P=0.014), but not in the MOG and MS groups (P=0.218 and P=0.138, respectively). There was no significant correlation between foveal thickness and visual field test in all three groups.

CONCLUSION

The significant thinning in the fovea and parafoveal areas in the AQP4 group compared to the MOG and MS groups are found. Additionally, macular changes in AQP4-ON show a significant correlation with VA. The results provide the possibility that retinal structural damage could reflect functional damage in AQP4-ON, distinct from MOG-ON and MS-ON.

Myelin Oligodendrocyte Glycoprotein (MOG) Associated Diseases: Updates in Pediatric Practice

Myelin oligodendrocyte glycoprotein (MOG) is a membrane bound protein found on the surface of oligodendrocyte cells and the outermost surface of myelin sheaths. MOG is posited to play a role as a cell surface receptor or cell adhesion molecule, though there is no definitive answer to its exact function at this time. In the last few decades, there has been a recognition of anti-MOG-antibodies (MOG-Abs) in association with a variety of neurologic conditions, though primarily demyelinating and white matter disorders. In addition, MOG associated disease (MOGAD) appears to have a predilection for pediatric populations and in some patients may have a relapsing course. There has been considerable debate as to whether MOG-Abs are truly directly pathogenic or a disease biomarker associated with neuorinflammatory disease. In this manuscript we will review the current literature surrounding MOGAD, review new clinical phenotypes, discuss treatment and prognosis, and provide insight into potential future directions that studies may focus on.

Clinical characteristics and prognosis of optic neuritis in Taiwan - a hospital-based cohort study

BACKGROUND

Optic neuritis (ON) is an inflammatory disease of optic nerve. The distinct etiologies of ON significantly influence its clinical manifestation, neuroimaging findings, and visual outcomes. However, the clinical characteristics might be influenced by the racial differences. The purpose of this study is to investigate the clinical characteristics of various types of ON at a Taiwanese tertiary center.

METHODS

This cohort study analyzed 163 patients who received treatment and continued following-up for ON between 2015 and 2022. We selected patients who had been tested for anti-aquaporin-4 antibody (AQP4-Ab) and anti-myelin oligodendrocyte glycoprotein antibody (MOG-Ab). The participants were classified into four groups on the basis of their etiologies, specifically (1) multiple sclerosis (MS)-related, (2) AQP4-Ab-positive, (3) MOG-Ab-positive, or (4) idiopathic ON. The researchers recorded the patients' clinical characteristics, treatment course, magnetic resonance imaging and optical coherence tomography (OCT) findings, and visual outcomes.

RESULTS

MOG-Ab-positive group had higher percentages of disk swelling and pain with eye movement. Long optic nerve and perineural enhancement are the hallmarks of MOG-Ab-related ON. The ON relapse rate was higher in AQP4-Ab-positive group. Although members of AQP4-Ab-positive group received immediate steroid pulse therapy, these patients experienced the worst visual outcomes. Moreover, a thinner retinal nerve fiber layer (RNFL) was noted in AQP4-Ab-positive group. MS group had a higher incidence of extra-optic nerve lesions. Multivariate regression identified pretreatment visual acuity and RNFL thickness as the important factors affecting visual outcomes.

CONCLUSIONS

This cohort study identified the clinical features of different types of ON. Patients with AQP4-Ab-positive ON had poorer visual outcomes, which may be attributed to multiple relapses and profound nerve damage, as revealed by OCT findings. Patients with MOG-Ab-positive ON displayed long optic nerve enhancement but had more favorable prognoses. Thus, antibody-based classification facilitates treatment and prognosis in ON.

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 clinical characteristics of three types of optic neuritis (double seronegative optic neuritis; DN-ON, Neuromyelitis optica spectrum disorder-related optic neuritis; NMOSD-ON, and multiple sclerosis-related optic neuritis; MS-ON) were examined in order to identify factors that may affect good visual recovery in Thai patients. The study included patients diagnosed with three types of optic neuritis at Rajavithi Hospital between 2011 and 2020. Visual acuity at the end of 12 months was used as the treatment outcome. Multiple logistic regression analysis was used to evaluate potential predictors of good visual recovery. Of the 76 patients, 61 had optic neuritis, with DN-ON as the most common subtype (52.6%). MS-ON patients were significantly younger (28.3 ± 6.6 years, p = 0.002) and there was a female predominance in all subgroups (p = 0.076). NMOSD-ON patients had a significantly higher proportion of poor baseline VA (p < 0.001). None of the NMOSD-ON patients achieved 0.3 logMAR visual recovery in the 12-month period (p = 0.022). A delay in treatment with intravenous methylprednisolone (IVMP) for more than 7 days increased the risk of failure to gain 0.3 logMAR visual recovery by five times (OR 5.29, 95% CI 1.359–20.616, p = 0.016), with NMOSD-ON as the strongest predictor (OR 10.47, 95% CI; 1.095–99.993, p = 0.041). Early treatment with intravenous methylprednisolone may be important for achieving at least 0.3 logMAR visual recovery in Thai patients with optic neuritis.

Anti-inflammatory effect of miR-125a-5p on experimental optic neuritis by promoting the differentiation of Treg cells

Methylprednisolone pulse treatment is currently used for optic neuritis. It can speed visual recovery, but does not improve the ultimate visual outcomes. Recent studies have reported that miR-125a-5p has immunomodulatory effects on autoimmune diseases. However, it remains unclear whether miR-125a-5p has effects on optic neuritis. In this study, we used adeno-associated virus to overexpress or silence miR-125a-5p in mice. We found that silencing miR-125a-5p increased the latency of visual evoked potential and aggravated inflammation of the optic nerve. Overexpression of miR-125a-5p suppressed inflammation of the optic nerve, protected retinal ganglion cells, and increased the percentage of Treg cells. Our findings show that miR-125a-5p exhibits anti-inflammatory effects through promoting the differentiation of Treg cells.

What's new in neuromyelitis optica spectrum disorder treatment?

Optic neuritis, an optic nerve inflammatory disease presenting with acute unilateral or bilateral visual loss, is one of the core symptoms of neuromyelitis optica spectrum disorder (NMOSD). The diagnosis of NMOSD-related optic neuritis is challenging, and it is mainly based on clinical presentation, optical coherence tomography, magnetic resonance imaging scans, and the status of serum aquaporin-4 antibodies. In the pathogenesis, aquaporin-4 antibodies target astrocytes in the optic nerves, spinal cord and some specific regions of the brain eliciting a devastating autoimmune response. Current pharmacological interventions are directed against various steps within the immunological response, notably the terminal complement system, B-cells, and the pro-inflammatory cytokine Interleukin 6 (IL6). Conventional maintenance therapies were off-label uses of the unspecific immunosuppressants azathioprine and mycophenolate mofetil as well as the CD20 specific antibody rituximab and the IL6 receptor specific antibody tocilizumab. Recently, four phase III clinical trials demonstrated the safety and efficacy of the three novel biologics eculizumab, inebilizumab, and satralizumab. These monoclonal antibodies are directed against the complement system, CD19 B-cells and the IL6 receptor, respectively. All three have been approved for NMOSD in the US and several other countries worldwide and thus provide convincing treatment options.