Clinical phenotype, radiological features, and treatment of myelin oligodendrocyte glycoprotein-immunoglobulin G (MOG-IgG) optic neuritis

Biomarkers for neuromyelitis optica: a visual analysis of emerging research trends

Neuromyelitis optica is an inflammatory demyelinating disease of the central nervous system that differs from multiple sclerosis. Over the past 20 years, the search for biomarkers for neuromyelitis optica has been ongoing. Here, we used a bibliometric approach to analyze the main research focus in the field of biomarkers for neuromyelitis optica. Research in this area is consistently increasing, with China and the United States leading the way on the number of studies conducted. The Mayo Clinic is a highly reputable institution in the United States, and was identified as the most authoritative institution in this field. Furthermore, Professor Wingerchuk from the Mayo Clinic was the most authoritative expert in this field. Keyword analysis revealed that the terms "neuromyelitis optica" (261 times), "multiple sclerosis" (220 times), "neuromyelitis optica spectrum disorder" (132 times), "aquaporin 4" (99 times), and "optical neuritis" (87 times) were the most frequently used keywords in literature related to this field. Comprehensive analysis of the classical literature showed that the majority of publications provide conclusive research evidence supporting the use of aquaporin-4-IgG and neuromyelitis optica-IgG to effectively diagnose and differentiate neuromyelitis optica from multiple sclerosis. Furthermore, aquaporin-4-IgG has emerged as a highly specific diagnostic biomarker for neuromyelitis optica spectrum disorder. Myelin oligodendrocyte glycoprotein-IgG is a diagnostic biomarker for myelin oligodendrocyte glycoprotein antibody-associated disease. Recent biomarkers for neuromyelitis optica include cerebrospinal fluid immunological biomarkers such as glial fibrillary acidic protein, serum astrocyte damage biomarkers like FAM19A5, serum albumin, and gamma-aminobutyric acid. The latest prospective clinical trials are exploring the potential of these biomarkers. Preliminary results indicate that glial fibrillary acidic protein is emerging as a promising candidate biomarker for neuromyelitis optica spectrum disorder. The ultimate goal of future research is to identify non-invasive biomarkers with high sensitivity, specificity, and safety for the accurate diagnosis of neuromyelitis optica.

Myelin Oligodendrocyte Glycoprotein-Antibody Associated Disease: An Updated Review of the Clinical Spectrum, Pathogenetic Mechanisms and Therapeutic Management

Clinical syndromes associated with antibodies against myelin oligodendrocyte glycoprotein (MOG) are now recognized as a distinct neurological disease entity, and are gaining increasing attention. The pathogenic mechanisms underlying MOG-antibody disease (MOGAD) remain incompletely understood. Case series, facilitated by registries, and observational studies over the past few years have shed increasing light on the clinical aspects and therapeutic approaches of MOGAD. MOGAD may manifest with a variety of clinical syndromes, including acute disseminated encephalomyelitis (ADEM), autoimmune encephalitis, optic neuritis (ON) and transverse myelitis (TM). MOGAD can be either monophasic or relapsing. This review aims to provide a comprehensive updated description of the clinical spectrum, paraclinical features, and prognosis of MOG-antibody disease, as well as summarize its therapeutic considerations. Randomized clinical trials, standardized diagnostic criteria and treatment guidelines are the steps forward.

Trans-Synaptic Degeneration in the Visual Pathway in Patients With Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease

BACKGROUND AND OBJECTIVES

We aimed to assess the presence of retinal neurodegeneration independent of optic neuritis (ON) in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) and to investigate the development of trans-synaptic anterograde degeneration in these patients after ON.

METHODS

Cross-sectional, retrospective study of 34 adult patients with MOGAD and 23 healthy controls (HC). Clinical, optical coherence tomography (OCT), and MRI data were collected. Peripapillary retinal nerve fiber layer (pRNFL) and ganglion cell inner plexiform layer (GCIPL) were obtained using Heidelberg Spectralis. FreeSurfer7 was used to obtain the lateral geniculate nucleus (LGN), occipital volume fractions (to total estimated intracranial volume), and occipital cortical thickness. For the anterior visual pathway, the analysis was conducted using eyes, classified based on the history of ON (Eye-ON and Eye-NON) and compared with Eye-HC. The analysis of OCT and brain volumetric measures was conducted comparing MOGAD-ON, MOGAD-NON, and HC groups. The analysis of covariance with a Bonferroni-adjusted post hoc test was used to test differences between groups and linear regression analysis to evaluate OCT/MRI associations; age and sex were considered as covariates.

RESULTS

24 (70.5%) patients had a prior ON. Median pRNFL and GCIPL thickness (um) was significantly reduced in Eye-ON vs EyeNON and HC (pRNFL: 69.4 (17.3), 89.6 (13.7), 98.2 (11.7), p < 0.001; GCIPL: 55.8 (8.7), 67.39 (8.7), 72.6 (4.5), p < 0.001). pRNFL and GCIPL thickness had a negative correlation with the number of ON episodes (p = 0.025 and p = 0.031, respectively). LGN volume fraction was significantly lower in patients with MOGAD-ON than in HC (0.33 (0.05) vs 0.39 (0.04), p = 0.002). The occipital cortical thickness was lower in MOGAD-ON compared with MOGAD-NON and HC (p = 0.010). In patients with MOGAD-ON, pRNFL correlated with LGN volume (p = 0.006), occipital thickness (p = 0.002), and the medial occipital cortex (p = 0.002), but not the lateral occipital lobe.

DISCUSSION

Compared with HC, MOGAD-ON exhibits reduced retinal thickness, primarily influenced by the presence and the number of prior ON episodes. Moreover, MOGAD-ON demonstrates significant atrophy in the retinal, subcortical, and cortical regions of the visual pathway, distinguishing them from MOGAD-NON and HC. These findings suggest that in patients with MOGAD neurodegeneration is tightly correlated with damage to the involved pathway.

A Comparative Review of Typical and Atypical Optic Neuritis: Advancements in Treatments, Diagnostics, and Prognosis

Optic neuritis (ON) is a debilitating condition that through various mechanisms, including inflammation or demyelination of the optic nerve, can result in partial or total permanent vision loss if left untreated. Accurate diagnosis and promptly initiated treatment are imperative related to the potential of permanent loss of vision if left untreated, which can lead to a significant reduction in the quality of life in affected patients. ON is subtyped as "typical" or "atypical" based on underlying causative etiology. The etiology of ON can be differentiated when appropriate diagnostic testing is performed. Using history taking, neuroimaging, and visual testing to localize the underlying pathology of ON in a time-sensitive manner is critical in mitigating these unsatisfactory outcomes. Herein, we examine the differences in presentation, pathophysiology, and treatments of typical ON causes, like multiple sclerosis (MS), and atypical causes such as neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein (MOG)-immunoglobulin G (IgG) ON. The present investigation places focus on both neuroimaging and visual imaging in the differentiation of ON. Additionally, this review presents physicians with a better understanding of different presentations, treatments, and prognoses of ON.

Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease: A Case Report

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a newly discovered autoimmune demyelinating disorder. The clinical manifestations of MOGAD are divergent but often characterized by inflammatory central nervous system (CNS) deficits such as optic neuritis, encephalitis, or transverse myelitis that predominantly affect the pediatric population. Despite the distinct features often associated with MOGAD, the disease exhibits a diverse range of clinical manifestations, making timely diagnosis and treatment challenging. In particular, distinguishing MOGAD from multiple sclerosis (MS) is important for adequate treatment and the prevention of relapsing disease. In this report, we present a rare case of MOGAD in a 57-year-old male who initially exhibited symptoms of bilateral optic nerve edema and flame hemorrhage. This led to an initial misdiagnosis of pseudotumor cerebri. Serological analysis at a tertiary care center ultimately led to the diagnosis of MOGAD after multiple visits to the ophthalmologist with worsening vision deficits.

Updates in NMOSD and MOGAD Diagnosis and Treatment: A Tale of Two Central Nervous System Autoimmune Inflammatory Disorders

Aquaporin-4-IgG positive neuromyelitis optica spectrum disorder (AQP4+NMOSD) and myelin-oligodendrocyte glycoprotein antibody-associated disease (MOGAD) are antibody-associated diseases targeting astrocytes and oligodendrocytes, respectively. Their recognition as distinct entities has led to each having its own diagnostic criteria that require a combination of clinical, serologic, and MRI features. The therapeutic approach to acute attacks in AQP4+NMOSD and MOGAD is similar. There is now class 1 evidence to support attack-prevention medications for AQP4+NMOSD. MOGAD lacks proven treatments although clinical trials are now underway. In this review, we will outline similarities and differences between AQP4+NMOSD and MOGAD in terms of diagnosis and treatment.

Visual outcome measures in pediatric myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD)

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) comprises various age-dependent clinical phenotypes and may be monophasic, multiphasic, or chronic. Optic neuritis (ON) is a common manifestation and frequently appears in combination with other MOGAD phenotypes, particularly in young children. Despite permanent structural damage to the retinal nerve fiber layer (RNFL), children often experience complete visual recovery.

AIMS

To analyze the progression and impact of MOGAD on the visual system of pediatric patients independently of the history of ON.

METHODS

This retrospective study included children who met specific criteria: myelin oligodendrocyte glycoprotein (MOG) immunoglobulin G (IgG) seropositivity, acute presentation of MOGAD, and written general consent. Main outcome measures were global peripapillary retinal nerve fiber layer (pRNFL) thickness, and near and distance visual acuity, analyzed using descriptive statistics.

RESULTS

We identified 10 patients with median age of 7.7 years at first event: 7 patients manifested with acute disseminated encephalomyelitis (ADEM) (with ON 5/7, ADEM only 1/7, with transverse myelitis (TM) 1/7), 2 with isolated ON, and 1 patient with neuromyelitis optica spectrum disorder (NMOSD)-like phenotype with ON. Among ON patients, 5/8 were affected bilaterally, with 3 initially diagnosed with unilateral ON but experiencing subsequent involvement of the fellow eye. None of the patients without previous ON showed a deterioration of visual acuity and, if evaluated, a reduction of the pRNFL.

CONCLUSION

Most pediatric MOGAD-ON patients in our cohort presented with acute vison loss and optic disc edema. All patients achieved complete visual recovery, independent of number of relapses or initial visual loss. The pRNFL thickness decreased for several months and stabilized at reduced levels after 12 months in the absence of further relapses. MOGAD may not have subclinical/'silent' effects on the visual system, as visual acuity and pRNFL were not affected in patients without ON.

Evidence-based management of optic neuritis

PURPOSE OF REVIEW

Optic neuritis can result from several distinct causes, including multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), and myelin oligodendrocyte glycoprotein antibody disease (MOGAD), when not idiopathic. This review discusses evidence-based treatment approaches contingent upon each specific cause of optic neuritis.

RECENT FINDINGS

Current evidence highlights the need for prompt plasmapheresis as adjunct to intravenous methylprednisolone (IVMP) in patients with NMOSD-associated optic neuritis. Recent advances have included a proliferation of novel disease modifying therapies (DMTs) for long-term management of NMOSD and an understanding of how existing therapeutic options can be leveraged to optimally treat MOGAD.

SUMMARY

In acute idiopathic or MS-associated optic neuritis, IVMP hastens visual recovery, though it does not substantially affect final visual outcomes. IVMP and adjunctive plasmapheresis are beneficial in the treatment of NMOSD-associated optic neuritis, with a shorter time-to-treatment associated with a higher likelihood of recovery. The natural history of untreated MOGAD-associated optic neuritis is unclear but treatment with IVMP is near-universal given phenotypic similarities with NMOSD. Long-term immunosuppressive therapy is warranted in patients with NMOSD as well as in patients with MOGAD with poor visual recovery or recurrent attacks.

Uncovering the Genetics and Physiology behind Optic Neuritis

Optic neuritis (ON) is an inflammatory condition affecting the optic nerve, leading to vision impairment and potential vision loss. This manuscript aims to provide a comprehensive review of the current understanding of ON, including its definition, epidemiology, physiology, genetics, molecular pathways, therapy, ongoing clinical studies, and future perspectives. ON is characterized by inflammation of the optic nerve, often resulting from an autoimmune response. Epidemiological studies have shown a higher incidence in females and an association with certain genetic factors. The physiology of ON involves an immune-mediated attack on the myelin sheath surrounding the optic nerve, leading to demyelination and subsequent impairment of nerve signal transmission. This inflammatory process involves various molecular pathways, including the activation of immune cells and the release of pro-inflammatory cytokines. Genetic factors play a significant role in the susceptibility to ON. Several genes involved in immune regulation and myelin maintenance have been implicated in the disease pathogenesis. Understanding the genetic basis can provide insights into disease mechanisms and potential therapeutic targets. Therapy for ON focuses on reducing inflammation and promoting nerve regeneration. Future perspectives involve personalized medicine approaches based on genetic profiling, regenerative therapies to repair damaged myelin, and the development of neuroprotective strategies. Advancements in understanding molecular pathways, genetics, and diagnostic tools offer new opportunities for targeted therapies and improved patient outcomes in the future.

Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease and COVID-19: A Systematic Review

Background

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an uncommon neurological disease affecting the central nervous system (CNS). Numerous neurological disorders, including multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), acute transverse myelitis (ATM), and MOGAD, have been reported following the COVID-19 infection during the current COVID-19 pandemic. On the other hand, it has been suggested that patients with MOGAD may be at greater risk for infection (particularly in the current pandemic).

Objective

In this systematic review, we gathered separately 1) MOGAD cases following COVID-19 infection as well as 2) clinical course of patients with MOGAD infected with COVID-19 based on case reports/series.

Methods

329 articles were collected from 4 databases. These articles were conducted from inception to March 1st, 2022.

Results

Following the screening, exclusion criteria were followed and eventually, 22 studies were included. In 18 studies, a mean ± SD time interval of 18.6 ± 14.9 days was observed between infection with COVID-19 and the onset of MOGAD symptoms. Symptoms were partially or completely recovered in a mean of 67 days of follow-up. Among 4 studies on MOGAD patients, the hospitalization rate was 25%, and 15% of patients were hospitalized in the intensive care unit (ICU).

Conclusion

Our systematic review demonstrated that following COVID-19 infection, there is a rare possibility of contracting MOGAD. Moreover, there is no clear consensus on the susceptibility of MOGAD patients to severe COVID-19. However, obtaining deterministic results requires studies with a larger sample size.

Discrepancy in clinical and laboratory profiles of NMOSD patients between AQP4 antibody positive and negative: can NMOSD be diagnosed without AQP4 antibody?

AQP4-IgG has been considered as the pathogenic factor leading to NMOSD. However, about 20-30% of patients lack AQP4-IgG. So far, all therapeutic medicines are ineffective for NMOSD patients without AQP4 IgG. Thus AQP4-IgG is the pathogenic factor of NMOSD has been suspected and challenged. In addition, lack of efficacy of immunotherapy in NMOSD without AQP4 IgG has been a serious problem in the neurology. Identifying the clinical and laboratory characteristics and diversities between NMOSD patients with and without AQP4-IgG can be helpful to further explore the pathogenesis of NMOSD and guide clinical treatment. This is a single-centre retrospective study in The First Hospital of Jilin University, China including 92 patients diagnosed as NMOSD from January 2013 to January 2015. The characteristics of clinic, blood, cerebrospinal fluid (CSF), and image between AQP4-IgG negative (AQP4-IgG-) and AQP4-IgG positive (AQP4-IgG+) NMOSDs were compared. Our results showed that in the AQP4-IgG+ group, the ratio of women to men was 5.55, while in AQP4-IgG- group was 1.54 (P = 0.0092). In the AQP4-IgG+ patients, the expanded disability status scale (EDSS) was from 0 to 8.5, with an average of 5.550 ± 0.25, and the AQP4-IgG- patients had the EDSS score from 0 to 9, with an average of 4.032 ± 0.36 (P = 0.0006), which mainly affected movement system (P < 0.05) and superficial sensory impairment (P < 0.05). In the AQP4-IgG+ group, the blood brain barrier (BBB) permeability (P = 0.0210) and myelin basic protein (MBP) were increased (P = 0.0310) when compared to AQP4-IgG- group. Higher level IL-17 was seen in AQP4-IgG+ group than AQP4-IgG- group (P= 0.0066). Our results demonstrated that the NMOSD with AQP4-IgG more likely occurred in women and presented more severe clinical symptoms as well as significant BBB damage and increased MBP and IL-17 in CSF and blood, respectively compared with NMOSD without AQP4-IgG group. The differences in clinical and laboratory profiles between NMOSD with and without AQP4-IgG indicate the heterogeneity of NMOSD, in which AQP4-IgG may not be the only pathogenic molecule. It is necessary to find more pathogenic factors and to explore the new pathogenesis of NMOSD and therapeutic methods in the future.

Visual Outcomes Following Plasma Exchange for Optic Neuritis: An International Multicenter Retrospective Analysis of 395 Optic Neuritis Attacks

PURPOSE

To evaluate the effectiveness of plasma exchange (PLEX) for optic neuritis (ON).

METHODS

We conducted an international multicenter retrospective study evaluating the outcomes of ON following PLEX. Outcomes were compared to raw data from the Optic Neuritis Treatment Trial (ONTT) using a matched subset.

RESULTS

A total of 395 ON attack treated with PLEX from 317 patients were evaluated. The median age was 37 years (range 9-75), and 71% were female. Causes of ON included multiple sclerosis (108), myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) (92), aquaporin-4-IgG-positive neuromyelitis optica spectrum disorder (AQP4+NMOSD) (75), seronegative-NMOSD (34), idiopathic (83), and other (3). Median time from onset of vision loss to PLEX was 2.6 weeks (interquartile range [IQR], 1.4-4.0). Median visual acuity (VA) at the time of PLEX was count fingers (IQR, 20/200-hand motion), and median final VA was 20/25 (IQR, 20/20-20/60) with no differences among etiologies except MOGAD-ON, which had better outcomes. In 81 (20.5%) ON attacks, the final VA was 20/200 or worse. Patients with poor outcomes were older (P = .002), had worse VA at the time of PLEX (P < .001), and longer delay to PLEX (P < .001). In comparison with the ONTT subset with severe corticosteroid-unresponsive ON, a final VA of worse than 20/40 occurred in 6 of 50 (12%) PLEX-treated ON vs 7 of 19 (37%) from the ONTT treated with intravenous methylprednisolone without PLEX (P = .04).

CONCLUSION

Most ON attacks improved with PLEX, and outcomes were better than attacks with similar severity in the ONTT. The presence of severe vision loss at nadir, older age, and longer delay to PLEX predicted a worse outcome whereas MOGAD-ON had a more favorable prognosis. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

MRI pattern in acute optic neuritis: Comparing multiple sclerosis, NMO and MOGAD

BACKGROUND

Several MRI findings of optic neuritis (ON) have been described and correlated with specific underlying etiologies. Specifically, optic nerve enhancement is considered an accurate biomarker of acute ON.

OBJECTIVE

To identify differences in MRI patterns of optic nerve enhancement in certain demyelinating etiologies presenting with acute ON.

METHODS

Retrospective analysis of enhancement patterns on fat-suppressed T1-weighted images from patients presenting clinical and radiological acute ON, treated at our institution between January 2014 and June 2022. Location and extension of enhancing optic nerve segments, as well as presence of perineural enhancement were evaluated in three predetermined demyelinating conditions. Fisher's exact test and chi2 were calculated.

RESULTS

Fifty-six subjects met eligibility criteria. Mean age was 31 years (range 6-79) and 70% were females. Thirty-four (61%) patients were diagnosed with multiple sclerosis (MS), 8 (14%) with neuromyelitis optica (NMO), and 14 (25%) with anti-myelin oligodendrocyte glycoprotein disease (MOGAD). Bilateral involvement was more frequent in MOGAD, compared to MS and NMO (43 vs 3% and 12.5% respectively, p = 0.002). MS patients showed shorter optic nerve involvement, whereas MOGAD showed more extensive lesions (p = 0.006). Site of involvement was intraorbital in 63% MS, 89% NMO, 90% MOGAD (p = 0.051) and canalicular in 43% MS, 33% NMO and 75% MOGAD (p = 0.039). Intracranial or chiasmatic involvement and presence of perineural enhancement were not statistically different between entities.

CONCLUSION

In the setting of acute ON, patients presenting MOGAD were more likely to show bilateral, longitudinally extended and anterior (intraorbital and canalicular) optic nerve involvement compared to patients with MS or NMO.

The Treatment of Acute Optic Neuritis

Despite the high incidence of optic neuritis (ON), and the growing number of therapeutic options for the long-term treatment of diseases associated with ON including multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD) and MOG antibody associated disease (MOGAD), there are still only limited therapeutic options for treating an acute event of optic neuritis. These include steroids, plasma exchange (PLEX) and intravenous immunoglobulin (IVIG). High-dose steroids remain the mainstay of acute treatment. However, evidence is emerging that when optic neuritis is accompanied with certain atypical features that suggest a more unfavorable outcome this mandates special consideration such as early addition of other therapeutic agents or tapering the steroid very slowly. This review will distinguish between typical and atypical neuritis and discuss acute treatment options.

Socioeconomic, Clinical, and Laboratory Parameters Differentiating Pediatric Patients With MOG Antibody-Associated Disease and Multiple Sclerosis

Studies indicate differences in the clinical phenotypes and neuroimaging of children with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) compared to multiple sclerosis; however, there are limited data assessing the socioeconomic and paraclinical differences between these distinct disorders. This retrospective study identified patients aged <18 years at time of diagnosis with MOGAD or multiple sclerosis. Demographics, birth history, socioeconomic factors (insurance type, median income, parental education level), and paraclinical features (clinical manifestations, laboratory evaluation) were recorded for eligible participants. Seventy-eight patients (28 MOGAD, 50 multiple sclerosis) met inclusion criteria. Mothers of MOGAD children were more likely to have attended college compared to the mothers of children with multiple sclerosis (80% vs 49%; P = .02). Though MOGAD patients had greater rates of day care attendance (81% vs 57%), lower rates of birth complications (7% vs 21%), and higher rates of being breastfed (65% vs 46%), these findings did not meet predefined statistical significance. Clinically, children with MOGAD exhibited a lower body mass index percentile at presentation (58th ± 27th percentile vs 83rd ± 20th percentile; P = .0001) and were younger (7.6 ± 4.1 vs 14.8 ± 1.6 years; P < .0001) and more likely to exhibit an infectious prodrome (57% vs 10%; P < .0001). MOGAD patients were less likely to have evidence of remote Epstein-Barr virus infection (29% vs 100%; P < .0001) and less likely to have ≥3 unique oligoclonal bands in the cerebrospinal fluid (5% vs 87%; P < .001). Compared with multiple sclerosis, children with MOGAD exhibit lower body mass index percentiles at presentation, are more likely to have mothers with higher education levels, and are less likely to have had prior Epstein-Barr virus infection. Our data confirm that MOGAD patients are younger, more likely to exhibit infectious prodrome, and are less likely to exhibit intrathecal synthesis of oligoclonal bands. These features provide new insights into the differentiating pathobiology of MOGAD and may be helpful in differentiating these children from multiple sclerosis early in the diagnostic evaluation.

Paediatric MOG-antibody disease presenting with intracranial hypertension and unilateral vision loss without radiological evidence of optic neuritis

Intracranial hypertension (IH) is poorly described in paediatric myelin oligodendrocyte glycoprotein antibody disease (MOGAD). We describe a unique case of seropositive MOGAD in an obese 13-year-old boy who presented with an isolated IH, bilateral optic disc swelling and sudden-onset complete vision loss in one eye without radiological evidence of optic nerve involvement. Treatment with intravenous methylprednisolone combined with an emergency shunt fully restored vision and resolved the optic disc swelling. This report adds to the growing body of evidence suggesting that obese children presenting with isolated IH should be investigated for MOGAD, and the importance of managing IH during MOGAD.

Diagnosis of Optic Disc Oedema: Fundus Features, Ocular Imaging Findings, and Artificial Intelligence

Optic disc swelling is a manifestation of a broad range of processes affecting the optic nerve head and/or the anterior segment of the optic nerve. Accurately diagnosing optic disc oedema, grading its severity, and recognising its cause, is crucial in order to treat patients in a timely manner and limit vision loss. Some ocular fundus features, in light of a patient's history and visual symptoms, may suggest a specific mechanism or aetiology of the visible disc oedema, but current criteria can at most enable an educated guess as to the most likely cause. In many cases only the clinical evolution and ancillary testing can inform the exact diagnosis. The development of ocular fundus imaging, including colour fundus photography, fluorescein angiography, optical coherence tomography, and multimodal imaging, has provided assistance in quantifying swelling, distinguishing true optic disc oedema from pseudo-optic disc oedema, and differentiating among the numerous causes of acute optic disc oedema. However, the diagnosis of disc oedema is often delayed or not made in busy emergency departments and outpatient neurology clinics. Indeed, most non-eye care providers are not able to accurately perform ocular fundus examination, increasing the risk of diagnostic errors in acute neurological settings. The implementation of non-mydriatic fundus photography and artificial intelligence technology in the diagnostic process addresses these important gaps in clinical practice.

Atypical myelin oligodendrocyte glycoprotein antibody-associated optic neuritis and acute demyelinating polyneuropathy after SARS-CoV-2 infection: Case report and literature review

Post-infectious immune-mediated neurological complications of Sars-Cov-2 have been increasingly recognized since the novel pandemic emerged. We describe the case of a 74 years-old patient who developed a Myelin Oligodendrocyte Glycoprotein (MOG) antibody-associated unilateral retrobulbar optic neuritis a few weeks after paucisymptomatic COVID-19 disease and, subsequently, after the resolution of the optic neuritis, an acute inflammatory demyelinating polyneuropathy. So far, no cases of these two neurological manifestations have been reported in the same patient. We herein report a case characterized by both manifestations and review the accumulating literature regarding MOG antibody-associated disease following SarsCov-2 infection.

Imaging of Central Nervous System Demyelinating Disorders

OBJECTIVE

This article summarizes neuroimaging findings in demyelinating disease, the most common being multiple sclerosis. Revisions to criteria and treatment options have been ongoing, and MRI plays a pivotal role in diagnosis and disease monitoring. The common antibody-mediated demyelinating disorders with their respective classic imaging features are reviewed, as well as the differential diagnostic considerations on imaging.

LATEST DEVELOPMENTS

The clinical criteria of demyelinating disease rely heavily on imaging with MRI. With novel antibody detection, the range of clinical demyelinating syndromes has expanded, most recently with myelin oligodendrocyte glycoprotein-IgG antibodies. Imaging has improved our understanding of the pathophysiology of multiple sclerosis and disease progression, and further research is underway. The importance of increased detection of pathology outside of the classic lesions will have an important role as therapeutic options are expanding.

ESSENTIAL POINTS

MRI has a crucial role in the diagnostic criteria and differentiation among common demyelinating disorders and syndromes. This article reviews the typical imaging features and clinical scenarios that assist in accurate diagnosis, differentiation between demyelinating diseases and other white matter diseases, the importance of standardized MRI protocols in clinical practice, and novel imaging techniques.

Predictors of Glucocorticoid Use for Acute Optic Neuritis in the United States, 2005-2019

PURPOSE

Acute optic neuritis (ON) is variably treated with glucocorticoids. We aimed to describe factors associated with glucocorticoid use.

METHODS

In this retrospective, longitudinal cohort study of insured patients in the United States (2005-2019), adults 18-50 years old with one inpatient or ≥2 outpatient diagnoses of ON within 90 days were included. Glucocorticoid use was classified as none, any dose, and high-dose (>100 mg prednisone equivalent ≥1 days). The primary outcome was glucocorticoid receipt within 90 days of the first ON diagnosis. Multivariable logistic regression models assessed the relationship between glucocorticoid use and sociodemographics, comorbidities, clinician specialty, visit number, and year.

RESULTS

Of 3026 people with ON, 65.8% were women (n = 1991), median age (interquartile range) was 38 years (31,44), and 68.6% were white (n = 2075). Glucocorticoids were received by 46% (n = 1385); 54.6% (n = 760/1385) of whom received high-dose. The odds of receiving glucocorticoids were higher among patients with multiple sclerosis (OR 1.61 [95%CI 1.28-2.04]; P < .001), MRI (OR 1.75 [95%CI 1.09-2.80]; P = .02), 3 (OR 1.80 [95%CI 1.46-2.22]; P < .001) or more (OR 4.08 [95%CI 3.37-4.95]; P < .001) outpatient ON visits, and in certain regions. Compared to ophthalmologists, patients diagnosed by neurologists (OR 1.36 [95%CI: 1.10-1.69], p = .005), emergency medicine (OR 3.97 [95%CI: 2.66-5.94]; P < .001) or inpatient clinicians (OR 2.94 [95%CI: 2.22-3.90]; P < .001) had higher odds of receiving glucocorticoids. Use increased 1.1% annually (P < .001).

CONCLUSIONS

Demyelinating disease, care intensity, setting, region, and clinician type were associated with glucocorticoid use for ON. To optimize care, future studies should explore reasons for ON care variation, and patient/clinician preferences.

Volumetric brain changes in MOGAD: A cross-sectional and longitudinal comparative analysis

BACKGROUND

Relatively little is known about how global and regional brain volumes changes in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) compare with Multiple Sclerosis (MS), Neuromyelitis optica spectrum disorder (NMOSD), and healthy controls (HC).

OBJECTIVE

To compare global and regional brain volumes in MOGAD, MS, NMOSD, and HC cross-sectionally as well as longitudinally in a subset of patients.

METHODS

We retrospectively reviewed all adult MOGAD and NMOSD patients with brain MRI performed in stable remission and compared them with MS patients and HC. Volumetric parameters were assessed using the FDA-approved icobrain software. adjusted for age and sex.

RESULTS

Twenty-four MOGAD, 47 NMOSD, 40 MS patients, and 37 HC were included in the cross-sectional analyses. Relative to HC, the age-adjusted whole brain (WB) volume was significantly lower in patients with MOGAD (p=0.0002), NMOSD (p=0.042), and MS (p=0.01). Longitudinal analysis of a subset of 8 MOGAD, 22 NMOSD, and 34 MS patients showed a reduction in the WB and cortical gray matter (CGM) volumes over time in all three disease groups, without statistically significant differences between groups. The MOGAD group had a greater loss of thalamic volume compared to MS (p=0.028) and NMOSD (p=0.023) and a greater loss of hippocampal volumes compared to MS (p=0.007).

CONCLUSIONS

Age-adjusted WB volume loss was evident in all neuroinflammatory conditions relative to HC in cross-sectional comparisons. In longitudinal analyses, MOGAD patients had a higher thalamic atrophy rate relative to MS and NMOSD, and a higher hippocampal atrophy rate relative to MS. Larger studies are needed to validate these findings and to investigate their clinical implications.

Recurrent Idiopathic Neuroretinitis: Anti-MOG Positive?

Neuroretinitis, originally described by Leber at the turn of the 20th century, has long perplexed ophthalmologists due to its multiple recognized causes and often atypical presentation. Optic disk edema and macular star in the affected eye are well-agreed upon findings and are due to increased permeability of blood vessels near the optic disk and in the retina at large. It also is universally painless and presents with a relative afferent pupillary defect (RAPD) in the affected eye or eyes. However, depending on the infectious agent, an underlying autoimmune condition, or undefined idiopathic cause, there can be various degrees of vision loss, visual field loss, progression or recurrence, as well as involvement of the other eye. We present this case of presumed sequential idiopathic neuroretinitis with severe vision and visual field loss with a low-positive anti-MOG test in the border county of El Paso.

Details and outcomes of a large cohort of MOG-IgG associated optic neuritis

BACKGROUND

The goal of this study was to examine the temporal relationship of eye pain to visual loss and investigate whether timing of steroid treatment affects the rate and extent of visual recovery in optic neuritis (ON) from MOG-IgG associated disease (MOGAD) in a large cohort of MOGAD patients with ON.

METHODS

This is a multicenter, retrospective cohort study of consecutive MOGAD patients with ON attacks seen from 2017 to 2021 fulfilling the following criteria: (1) clinical history of ON; (2) MOG-IgG seropositivity. ON attacks were evaluated for presence/duration of eye pain, nadir of vision loss, time to intravenous methylprednisolone (IVMP) treatment, time to recovery, and final visual outcomes.

RESULTS

There were 107 patients with 140 attacks treated with IVMP and details on timing of treatment and outcomes. Eye pain was present in 125/140 (89%) attacks with pain onset a median of 3 days (range, 0 to 20) prior to vision loss. Among 46 ON attacks treated with IVMP within 2 days of onset of vision loss, median time to recovery was 4 days (range, 0 to 103) compared to 15 days (range, 0 to 365) in 94 ON attacks treated after 2 days (p = 0.004). Those treated within 2 days had less severe VA loss at time of treatment (median LogMAR VA 0.48, range, 0.1 to 3) compared to those treated after 2 days (median LogMAR VA 1.7, range, 0 to 3; p < 0.001), and were more likely to have a VA outcome of 20/40 or better (98% vs 83%, p = 0.01). After adjustment for the initial VA at time of treatment, the differences in final VA were no longer significantly different (p = 0.14). In addition, some patients were documented to recover without steroid treatment.

CONCLUSION

This study suggests that pain precedes vision loss in the majority of ON attacks and early steroids may lead to better outcomes in MOG-IgG ON, but some patients can recover without steroid treatment. Prospective randomized clinical trials are required to confirm these findings.

Bilateral Optic Neuritis after COVID-19 Vaccination: A Case Report

BACKGROUND

Neuro-ophthalmic manifestations after vaccines are rare, with optic neuritis (ON) being the most common presentation. Patients with vaccine-related ON are similar to those with idiopathic ON. The temporal relationship between vaccination against and the occurrence of ON is vital. Here, we report a case of bilateral ON after the administration of the ChAdOx1-S nCoV-19 SARS-CoV-2 vaccine.

CASE

A 49-year-old healthy Asian female presented with sudden onset of bilateral blurred vision within 2 days. She complained of photophobia and extraocular pain upon movement over 3 days. Upon examination, her best corrected visual acuity (BCVA) was 20/30 in the right eye and 20/200 in the left eye. Anterior segment findings were unremarkable, with normal intraocular pressure. Fundoscopic examination revealed bilateral disc edema with vessel engorgement. Visual field examination revealed profound visual field defect in both eyes. She denied any trauma, use of new medication or medical history. She had received the ChAdOx1 nCoV-19 SARS-CoV-2 vaccine 14 days prior. Under suspicion of vaccine-related optic neuritis, she was given intravenous methylprednisolone 1 gm/day for 3 days, shifting to oral prednisolone under gradual tapering for 2 weeks.

CONCLUSIONS

Typically presenting with sudden-onset visual decline and extraocular pain during movement, acute ON is generally idiopathic. Bilateral ON is rare, but quick identification is important because it can potentially lead to permanent loss of vision if left untreated. Vaccination-induced ON is even rarer but not difficult to treat. However, such patients require further evaluation and long-term follow-up because they may be prone to other neurological disorders in the future.

Diagnostik der Neuromyelitis-optica-Spektrum-Erkrankung (NMOSD) und der MOG-Antikörper-assoziierten Erkrankung (MOGAD)

Die Aquaporin-4-Antikörper-positive Neuromyelitis-optica-Spektrum-Erkrankung (engl. NMOSD) und die Myelin-Oligodendrozyten-Glykoprotein-Antikörper-assoziierte Erkrankung (engl. MOGAD) sind Autoimmunerkrankungen des zentralen Nervensystems. Typische Erstmanifestationen sind bei Erwachsenen Optikusneuritis und Myelitis. Eine Beteiligung auch von Hirn und Hirnstamm, spätestens im weiteren Verlauf, ist häufig. Während die NMOSD nahezu immer schubförmig verläuft, nimmt die MOGAD gelegentlich einen monophasischen Verlauf. Die Differenzialdiagnostik ist anspruchsvoll und stützt sich auf u. a. auf radiologische und serologische Befunde. Die Abgrenzung von der häufigeren neuroinflammatorischen Erkrankung, Multiple Sklerose (MS), ist von erheblicher Bedeutung, da sich Behandlung und langfristige Prognose von NMOSD, MOGAD und MS wesentlich unterscheiden. Die vielfältigen Symptome und die umfangreiche Diagnostik machen eine enge Zusammenarbeit zwischen Ophthalmologie, Neurologie und Radiologie erforderlich. Dieser Artikel gibt einen Überblick über typische MRT-Befunde und die serologische Antikörperdiagnostik bei NMOSD und MOGAD. Zwei illustrative Fallberichte aus der ärztlichen Praxis ergänzen die Darstellung.

Plasma Complement 3 and Complement 4 Are Promising Biomarkers for Distinguishing NMOSD From MOGAD and Are Associated With the Blood-Brain-Barrier Disruption in NMOSD

Background and Objective

Neuromyelitis optica spectrum disorders (NMOSD) and myelin oligodendrocyte glycoprotein antibody (MOG-IgG) associated disease (MOGAD) are autoimmune inflammatory demyelinating diseases of the central nervous system (CNS). As the clinical features of NMOSD are similar to MOGAD, diagnostic confusion exists between the two diseases. To better discriminate NMOSD from MOGAD, we investigated whether the plasma levels of complement 3 (C3) and complement 4 (C4) are different in NMOSD and MOGAD during the acute attacks of the diseases. We sought to determine whether C3 or C4 has an influence on the features of NMOSD.

Methods

In this observational study, data from 73 aquaporin-4 antibodies (AQP4-IgG) positive NMOSD patients and 22 MOG-IgG positive MOGAD patients were collected retrospectively. Demographics, clinical characteristics, plasma parameters, and cerebrospinal fluid (CSF) findings will be analyzed for comparability between the two groups. Immunoglobulin-G (IgG) and albumin were measured in both plasma and CSF. Plasma levels of C3 and C4 were measured and compared between the NMOSD, MOGAD, and 42 healthy controls (HC). The correlations between plasma C3, C4, and NMOSD clinical parameters were analyzed.

Results

The ages of onset were later in the AQP4-IgG positive NMOSD group and females predominated, which differed from the MOGAD group, whose ages were younger and with a slight male preponderance. The AQP4-IgG positive NMOSD patients presented with the clinical symptoms of optic neuritis (ON) and transverse myelitis (TM), whereas encephalitis symptoms were more prevalent in MOGAD patients. CSF analysis shows that slight but not significantly higher white cell count (WCC) and protein were observed in the MOGAD group than in the AQP4-IgG positive NMOSD group. The plasma levels of IgG in MOGAD patients are significantly lower (p = 0.027) than in NMOSD patients. On the contrary, the plasma levels of albumin in MOGAD were higher than in NMOSD, which reached statistical significance (p = 0.039). Both the plasma C3 and C4 levels in the NMOSD group were significantly lower than in MOGAD and HC. The receiver operating characteristic (ROC) curve of the prediction model comprises C3 and C4 to distinguish NMOSD from MOGAD [area under the curve (AUC): 0.731, 0.645], which are considered to have discriminatory values. The results of Spearman’s analysis revealed that there was a significant positive correlation between the plasma C3 and the CSF WCC (r = 0.383, p = 0.040). There was an inverse correlation between plasma C4 and plasma IgG (r = -0.244, p = 0.038). Plasma C3 or C4 was significantly positively correlated with CSF albumin and Q-Alb, which is considered a measure of blood-brain barrier (BBB) disruption.

Conclusion

During the acute phase of NMOSD and MOGAD, plasma C3 and C4 may become potential biomarkers for distinguishing the two diseases and reflecting the NMOSD BBB damage.

Optic chiasm, optic tract and deep white demyelination: an unusual distribution of myelin oligodendrocyte glycoprotein-associated demyelination (MOGAD), case report and review of literature

A preschool girl presented with sudden-onset bilateral painless loss of vision from 2 days prior. Child's examination showed light perception vision, sluggishly reacting pupils, otherwise normal anterior segment, healthy optic disc and retina in both eyes. MRI of brain and orbit with contrast revealed thickened left part of the optic chiasm with contrast enhancement extending proximally to bilateral optic tract and hyperintensities in the left thalamus and periventricular white mater. Considering the topographical distribution of lesions in the brain, neuromyelitis optica spectrum disorder was suspected. The child was started on intravenous methylprednisolone followed by tapering oral steroids. Serological testing was positive for myelin oligodendrocyte glycoprotein (MOG) and negative for aquaporin-4 antibodies. This case represents an unusual case of MOG associated demyelination disorder where the distribution of lesions showed chiasmal involvement along with optic tract, thalamus and deep white mater lesions.

Progress in treatment of neuromyelitis optica spectrum disorders (NMOSD): Novel insights into therapeutic possibilities in NMOSD

Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune inflammatory demyelinating disorder of the central nervous system (CNS), which is a severely disabling disorder leading to devastating sequelae or even death. Repeated acute attacks and the presence of aquaporin-4 immunoglobulin G (AQP4-IgG) antibody are the typical characteristics of NMOSD. Recently, the phase III trials of the newly developed biologicals therapies have shown their effectiveness and good tolerance to a certain extent when compared with the traditional therapy with the first- and second-line drugs. However, there is still a lack of large sample, double-blind, randomized, clinical studies to confirm their efficacy, safety, and tolerability. Especially, these drugs have no clear effect on NMOSD patients without AQP4-IgG and refractory patients. Therefore, it is of strong demand to further conduct large sample, double-blind, randomized, clinical trials, and novel therapeutic possibilities in NMOSD are discussed briefly here.

Neuro-Ophthalmological Complications of the COVID-19 Vaccines: A Systematic Review

BACKGROUND

A worldwide mass vaccination campaign against the coronavirus disease 2019 (COVID-19) pandemic is currently underway. Although the safety data of the clinical trials did not report specific concerns regarding neuro-ophthalmological adverse events, they involved a limited number of individuals and were conducted over a relatively short time. The aim of the current review is to summarize the available postmarketing data regarding the occurrence of neuro-ophthalmological and other ocular complications of the COVID-19 vaccines.

EVIDENCE ACQUISITION

Electronic searches for published literature were conducted using Ovid MEDLINE, Embase, Web of Science, Google Scholar, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and ClinicalTrials.gov. The search strategy incorporated controlled vocabulary and free-text synonyms for the concepts of COVID, vaccines, and visual and neuro-ophthalmologic diseases and symptoms.

RESULTS

A total of 14 case reports and 2 case series have been selected for inclusion in the final report, reporting 76 cases of post-COVID-vaccination adverse events. The most common adverse event was optic neuritis (n = 61), followed by uveitis (n = 3), herpes zoster ophthalmicus (n = 2), acute macular neuroretinopathy (n = 2), optic disc edema as an atypical presentation of Guillain-Barré syndrome (n = 1), (arteritic anterior ischemic optic neuropathy; n = 1), abducens nerve palsy (n = 1), oculomotor nerve palsy (n = 1), Tolosa-Hunt syndrome (n = 1), central serous retinopathy (n = 1), acute zonal occult outer retinopathy (n = 1), and bilateral choroiditis (n = 1). Most cases were treated with high-dose steroids and had a favorable clinical outcome.

CONCLUSION

Since the implementation of the COVID-19 vaccination campaign in the past year, several post-COVID-vaccination neuro-ophthalmological complications have been described. However, considering the number of individuals that have been exposed to the vaccines, the risk seems very low, and the clinical outcome in most cases is favorable. Therefore, on a population level, the benefits of the vaccines far outweigh the risk of neuro-ophthalmological complications.

Comparison of neutrophil-to-lymphocyte ratio between myelin oligodendrocyte glycoprotein antibody-associated disease and aquaporin-4 antibody-positive neuromyelitis optica spectrum disorders in adults

The neutrophil-to-lymphocyte ratio (NLR) is a biomarker for evaluating disease activity in systemic autoimmune diseases. However, few studies have discussed NLR changes in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). This study aimed to explore the NLR difference between MOGAD, aquaporin-4 antibody (AQP4-Ab)-positive neuromyelitis optica spectrum disorders (NMOSD), and healthy controls (HCs) and evaluate the clinical value of NLR in the differential diagnosis. We included 15 patients with MOGAD, 28 patients with AQP4-Ab-positive NMOSD, and 68 HCs. Their NLRs were calculated, and statistical analysis was performed, with statistical significance set at P < 0.05. In pairwise comparisons between three groups, P < 0.017 was considered statistically significant under Bonferroni correction. NLR was higher during the acute attack in MOGAD patients than HCs but lower than in AQP4-Ab-positive NMOSD patients. NLR was correlated with Expanded Disability Status Scale (EDSS) in MOGAD and AQP4-Ab-positive NMOSD patients. Also, there were no statistical differences in intracranial pressure between MOGAD and AQP4-Ab-positive NMOSD patients and HCs. The cut-off value was 2.86, and the sensitivity and specificity were 0.750 and 0.867, respectively. In conclusion, our results suggest that NLR may be a helpful marker to evaluate disease severity and differentiate between both diseases at a cut-off value of > 2.86 when patients have clinical symptoms like optic neuritis or myelitis.

A Rare Case of Myelin Oligodendrocyte Glycoprotein Antibody-Associated Transverse Myelitis in a 40-Year-Old Patient With COVID-19

The coronavirus disease 2019 (COVID-19) includes an extensive spectrum of clinical manifestations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Previous studies have shown that SARS-CoV-2 often exhibits central nervous system (CNS) manifestations, including encephalitis, meningitis, and spinal cord pathologies. To date, few cases of COVID-19-associated transverse myelitis (TM) have been described. A 40-year-old unvaccinated man with no significant medical history presented to the emergency department complaining of fever, worsening burning sensation in his lower extremities, unsteady gait, and difficulty initiating urination for five days. Twelve days before presentation, the patient had tested positive for SARS-CoV-2 infection. Physical examination revealed hyperesthesia, starting around the nipple line (T4) and extending distally, involving the lower extremities, accompanied by symmetric weakness in the lower extremities. Magnetic resonance imaging of the thoracic spine with and without contrast revealed mild intramedullary signal abnormality at T3-T4 and T6-T8, confirming the suspicion of TM. Further laboratory testing revealed a C-reactive protein level of 67 mg/L, lactate dehydrogenase level of 181 mg/L, serum B12 level of 781 pg/mL, methylmalonic acid level of 165 nmol/L, folate of >24.5 ng/mL, and thyroid-stimulating hormone level of 0.481 μIU/L. Lumbar puncture was performed, and cerebrospinal fluid analysis revealed a cell count of 14 cells/µL, with 69% lymphocytes, glucose level of 81 mg/dL, protein level of 32 mg/dL, and negative cultures. Human immunodeficiency virus, antinuclear antibody screening, anti-DNA, rapid plasma reagin, Lyme serology, anti-SSA, and anti-SSB antibodies were unremarkable. Serum aquaporin-4 immunoglobulin G was negative, and myelin oligodendrocyte glycoprotein (MOG) antibodies were positive. The patient was treated with intravenous methylprednisolone and oral gabapentin and was discharged after five days when his urinary retention improved. Most previously reported cases of COVID-19-related TM were negative for autoimmune workup. Although the exact pathophysiology of COVID-19-related TM remains unclear, one hypothesis suggests that it is a consequence of the direct viral invasion. However, our patient had MOG antibodies, suggesting the possible involvement of a different mechanism. In MOG-associated TM, it has been suggested that MOG antibodies gain access to the CNS through disruption of the blood-brain barrier. This unique presentation demonstrates that further studies are needed to understand the effects of SARS-CoV-2 infection on the immune and nervous systems. It also highlights that young and otherwise healthy patients are at risk of severe COVID-19-related complications, including CNS disorders.

A Longitudinal Comparison of the Recovery Patterns of Optic Neuritis with MOG Antibody-Seropositive and AQP4 Antibody-Seropositive or -Seronegative for Both Antibodies

In this study, the aim is to compare the recovery pattern among patients with acute myelin oligodendrocyte glycoprotein antibody-seropositive optic neuritis (MOG-Ab + ON) attacks and aquaporin-4 antibody-seropositive ON (AQP4-Ab + ON) or -seronegative ON. At the onset of the first-ever ON attack, the thickness of RNFL (RNFLt) in the MOG-Ab + ON group was significantly thicker than others ( $P<0.05$ ), while visual function damage was not significantly different to other groups. One month to six months after onset, the MOG-Ab + ON group showed significantly better visual function ( $P<0.05$ ) than the other two groups, while the RNFLt showed no significant difference among the three groups ( $P>0.05$ ). MOG-Ab + ON and AQP4-Ab + ON groups showed rapid recovery in the first month and then plateaued. The annual relapse rate was significantly higher in MOG-Ab + ON and AQP4-Ab + ON groups than seronegative ON. The relapse interval of the MOG-Ab + ON group (9.00 ± 7.86 months) was significantly shorter than that of the AQP4-Ab + ON group (45.76 ± 37.82 months) ( $P<0.05$ ) but showed no significant difference from that of the seronegative ON group ( $P>0.05$ ). To sum up, the recovery patterns were different among these three types of ON. RNFLt was not parallel to the recovery of visual function among these types of ON. MOG-Ab + ON had the mildest visual function damage but the most substantial RNFL changes, while AQP4-Ab + ON suffered the worst function damage. MOG-Ab + ON had a similar relapse rate as AQP4-Ab + ON but a shorter interval, indicating that relapse prevention was necessary and should be initiated as early as possible.

Optic Neuritis in the Era of NMOSD and MOGAD: A Survey of Practice Patterns in Singapore

PURPOSE

The Optic Neuritis Treatment Trial was a landmark study with implications worldwide. In the advent of antibody testing for neuromyelitis optica spectrum disease (NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), emerging concepts, such as routine antibody testing and management, remain controversial, resulting mostly from studies in White populations. We evaluate the practice patterns of optic neuritis investigation and management by neuro-ophthalmologists and neurologists in Singapore.

DESIGN

21-question online survey consisting of 4 clinical vignettes.

METHODS

The survey was sent to all Singapore Medical Council- registered ophthalmologists and neurologists who regularly manage patients with optic neuritis.

RESULTS

Forty-two recipients (17 formally trained neuro-ophthalmol-ogists [100% response rate] and 25 neurologists) responded. Participants opted for routine testing of anti-aquaporin-4 antibodies (88.1% in mild optic neuritis and 97.6% in severe optic neuritis). Anti-MOG antibodies were frequently obtained (76.2% in mild and 88.1% in severe optic neuritis). Plasmapheresis was rapidly initiated (85.7%) in cases of nonresponse to intravenous steroids, even before obtaining anti-aquaporin-4 or anti-MOG serology results. In both NMOSD and MOGAD, oral mycophenolate mofetil was the preferred option if chronic immunosuppression was necessary. Steroids were given for a longer duration and tapered more gradually than in idiopathic optic neuritis cases.

CONCLUSIONS

Serological testing for NMOSD and MOGAD is considered as a routine procedure in cases of optic neuritis in Singapore, possibly due to local epidemiological features of these conditions. Chronic oral immunosuppression is preferred for the long term, but further research is necessary to establish the efficacy and cost-effectiveness of these practices.

Comparative study of AQP4-NMOSD, MOGAD and seronegative NMOSD: a single-center Belgian cohort

Purpose

To emphasize physio-pathological, clinical and prognosis differences between conditions causing serious and sometimes very similar clinical manifestations: anti-aquaporin-4 (AQP4) and anti-myelin oligodendrocyte glycoprotein (MOG) antibodies related diseases, and seronegative NMOSD (neuromyelitis optica spectrum disorders).

Methods

Based on Wingerchuk et al. (Neurology 85:177–189, 2015) criteria for NMOSD and on those more recently proposed by Jarius et al. (J Neuroinflammation 15:134, 2018) for MOGAD (MOG associated disorders), we retrospectively surveyed 10 AQP4-NMOSD, 8 MOGAD and 2 seronegative NMOSD, followed at the specialized neuroimmunology unit of the CHU Liège.

Results

Female predominance was only observed in AQP4 group. Age at onset was 37.8 and 27.7 years old for AQP4-NMOSD and MOGAD respectively. In both groups, the first clinical event most often consisted of optic neuritis (ON), followed by isolated myelitis. Fifteen of our 20 patients encountered a relapsing course with 90% relapses in AQP4-NMOSD, 62.5% in MOGAD and 50% in seronegative group, and a mean period between first and second clinical event of 7.1 and 4.8 months for AQP4-NMOSD and MOGAD, respectively. In total we counted 54 ON, with more ON per patient in MOGAD. MOG-associated ON mainly affected the anterior part of the optic nerve with a papilledema in 79.2% of cases. Despite a fairly good visual outcome after MOG-associated ON, retinal nerve fibre layer (RNFL) thickness decreased, suggesting a fragility of the optic nerve toward further attacks.

Conclusion

As observed in larger cohorts, our MOGAD and AQP4-NMOSD cases differ by clinical and prognostic features. A better understanding of these diseases should encourage prompt biological screening and hasten proper diagnosis and treatment.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13760-021-01712-3.

OCT retinal nerve fiber layer thickness differentiates acute optic neuritis from MOG antibody-associated disease and Multiple Sclerosis: RNFL thickening in acute optic neuritis from MOGAD vs MS

BACKGROUND

Optic neuritis (ON) is the most common manifestation of myelin oligodendrocyte glycoprotein antibody associated disorder (MOGAD) and multiple sclerosis (MS). Acute ON in MOGAD is thought to be associated with more severe optic disk edema than in other demyelinating diseases, but this has not been quantitatively confirmed. The goal of this study was to determine whether optical coherence tomography (OCT) can distinguish acute ON in MOGAD from MS, and establish the sensitivity of OCT as a confirmatory biomarker of ON in these entities.

METHODS

This was a multicenter cross-sectional study of MOGAD and MS patients with peripapillary retinal nerve fiber layer (pRNFL) thickness measured with OCT within two weeks of acute ON symptom. Cirrus HD-OCT (Carl Zeiss Meditec, Inc. Dublin, CA, USA) was used to measure the pRNFL during acute ON. Eyes with prior ON or disk pallor were excluded. A receiver operating characteristic (ROC) curve analysis was performed to assess the ability of pRNFL thickness to distinguish MOGAD from MS.

RESULTS

Sixty-four MOGAD and 50 MS patients met study inclusion criteria. Median age was 46.5 years (interquartile range [IQR]: 34.3-57.0) for the MOGAD group and 30.4 years (IQR: 25.7-38.4) for the MS group (p<0.001). Thirty-nine (61%) of MOGAD patients were female compared to 42 (84%) for MS (p = 0.007). The median pRNFL thickness was 164 µm (IQR: 116-212) in 96 acute MOGAD ON eyes compared to 103 µm (IQR: 93-113) in 51 acute MS ON eyes (p<0.001). The ROC area under the curve for pRNFL thickness was 0.81 (95% confidence interval 0.74-0.88) to discriminate MOGAD from MS. The pRNFL cutoff that maximized Youden's index was 118 µm, which provided a sensitivity of 74% and specificity of 82% for MOGAD. Among 31 MOGAD and 48 MS eyes with an unaffected contralateral eye or a prior baseline, the symptomatic eye had a median estimated pRNFL thickening of 45 µm (IQR: 17-105) and 7.5 µm (IQR: 1-18), respectively (p<0.001). All MOGAD affected eyes had a ≥ 5 µm pRNFL thickening, whereas 26 (54%) MS affected eyes had a ≥ 5 µm thickening.

CONCLUSION

OCT-derived pRNFL thickness in acute ON can help differentiate MOGAD from MS. This can aid with early diagnosis and guide disease-specific therapy in the acute setting before antibody testing returns, and help differentiate borderline cases. In addition, pRNFL thickening is a sensitive biomarker for confirming acute ON in MOGAD, which is clinically helpful and could be used for adjudication of attacks in future MOGAD clinical trials.

Clinical predictive factors for diagnosis of MOG-IgG and AQP4-IgG related paediatric optic neuritis: a Chinese cohort study

BACKGROUND

Different glial-autoantibodies-related paediatric optic neuritis (ON) are associated with different clinical characteristics and prognosis that require different treatments. Because glial autoantibody detection is not available in some parts of the world and there is often a delay in obtaining results, clinical factors that can be used to predict the subtype of paediatric ON are needed.

METHODS

This was a single-centre retrospective cohort study. Children who presented with their first ON attack and with complete clinical data were included in the analysis. Single and multiple parameters for predicting paediatric myelin oligodendrocyte glycoprotein immunoglobin-associated ON (MOG-ON) and aquaporin-4 immunoglobin-related ON (AQP4-ON) were calculated.

RESULTS

78 paediatric patients had their first ON attack from January 2016 to December 2019, of whom 69 were included in the final analysis, including 33 MOG-ON cases, 17 AQP4-ON cases and 19 Seronegative-ON cases. For predicting paediatric MOG-ON, the most sensitive predictors were 'male or optic disc swelling (ODS) or bilateral' (sensitivity 0.97 (95% CI 0.82 to 1.00)) and 'follow-up visual acuity (VA) ≤0.1 logMAR or ODS' (sensitivity 0.97 (95% CI 0.82 to 1.00)), and the most specific factor was 'Age ≤11 y and simultaneous CNS involvement' (specificity 0.97 (95% CI 0.84 to 1.00)). For predicting paediatric AQP4-ON, the most sensitive predictor was 'Female or without ODS' (sensitivity 1.00 (95% CI 0.77 to 1.00)), and the most specific factors were Neurological history (sensitivity 0.94 (95% CI 0.83 to 0.98)) and follow-up VA >1.0 logMAR (sensitivity 0.96 (95% CI 0.86 to 0.99)).

CONCLUSION

According to our data from a Chinese paediatric cohort, using multiple parameters increases the sensitivity and specificity of diagnosing paediatric MOG-ON and AQP4-ON. These can assist clinicians in diagnosing and treating paediatric ON when glial autoantibody status is not available.

Pain Symptoms in Optic Neuritis

Signs and symptoms of optic neuritis (ON), an autoimmune disorder of the central nervous system (CNS), differ between patients. Pain, which is commonly reported by ON patients, may be the major reason for some patients to visit the clinic. This article reviews the presence of pain related to ON with respect to underlying disorders, including multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), and myelin oligodendrocyte glycoprotein associated disease (MOGAD). The aim of this review is to provide an overview of pain symptoms in accordance with the context of various pathophysiological explanations, assist in differential diagnosis of ON patients, especially at the onset of disease, and make recommendations to aid physicians make decisions for follow up diagnostic examinations.

The changing landscape of optic neuritis: a narrative review

Optic neuritis (ON) is an inflammatory optic neuropathy that is often a harbinger of central nervous system (CNS) demyelinating disorders. ON is frequently misdiagnosed in the clinical arena, leading to either inappropriate management or diagnostic delays. As a result, patients may fail to achieve optimal recovery. The treatment response to corticosteroids and long term risk of multiple sclerosis was established in the first clinical trials conducted roughly 30 years ago. Spontaneous resolution was observed in the vast majority of patients and intravenous high-dose corticosteroids hastened recovery; half of the patients eventually developed multiple sclerosis. Over the ensuing decades, the number of inflammatory conditions associated with ON has significantly expanded exposing substantial variability in the prognosis, treatment, and management of ON patients. ON subtypes can frequently be distinguished by distinct clinical, serological, and radiological profiles allowing expedited and specialized treatment. Guided by an increased understanding of the immunopathology underlying optic nerve and associated CNS injuries, novel disease management strategies are emerging to minimize vision loss, improve long-term surveillance strategies, and minimize CNS injury and disability. Knowledge regarding the clinical signs and symptoms of different ON subtypes is essential to guide acute therapy, prognosticate recovery, accurately identify underlying CNS inflammatory disorders, and facilitate study design for the next generation of clinical and translational trials.

Clinical and Radiological Characteristics of Children and Adults With First-Attack Myelin Oligodendrocyte Glycoprotein Antibody Disease and Analysis of Risk Factors for Predicting the Severity at Disease Onset in Central China

Objective

To analyze and compare different clinical, laboratory, and magnetic resonance imaging characteristics between pediatric and adult patients with first-attack myelin oligodendrocyte glycoprotein antibody disease (MOGAD) and to explore predictive factors for severity at disease onset.

Methods

Patients diagnosed with MOGAD at the First Affiliated Hospital of Zhengzhou University from January 2013 to August 2021 were enrolled in this retrospective study. Age at disease onset, sex, comorbidities, laboratory tests, magnetic resonance imaging (MRI) characteristics, and Expanded Disability Status Scale (EDSS) scores were collected and analyzed. The association between risk factors and initial EDSS scores at disease onset was analyzed using logistic regression models and Spearman correlation analyses. A receiver-operating characteristic (ROC) curve analysis was used to evaluate the predictive ability of the uric acid and homocysteine (Hcy) levels for the severity of neurological dysfunction at the onset of MOGAD.

Results

Sixty-seven patients (female, n=34; male, n=33) with first-attack MOGAD were included in this study. The mean age at onset was 26.43 ± 18.22 years (range: 3–79 years). Among patients &lt;18 years of age, the most common presenting symptoms were loss of vision (36.0%), and nausea and vomiting (24.0%), and the most common disease spectrum was acute disseminated encephalomyelitis (ADEM) (40.0%). Among patients aged ≥18 years, the most common presenting symptoms were loss of vision (35.7%), paresthesia (33.3%), and paralysis (26.2%), and the most common disease spectrum was optic neuritis (35.7%). The most common lesions were cortical gray matter/paracortical white matter lesions in both pediatric and adult patients. Uric acid [odds ratio (OR)=1.014; 95% confidence interval (CI)=1.006–1.022; P=0.000] and serum Hcy (OR=1.125; 95% CI=1.017–1.246; P=0.023) levels were significantly associated with the severity of neurological dysfunction at disease onset. Uric acid levels (r=0.2583; P=0.035) and Hcy levels (r=0.3971; P=0.0009) were positively correlated with initial EDSS scores. The areas under the ROC curve were 0.7775 (95% CI= 0.6617‒0.8933; P&lt;0.001) and 0.6767 (95% CI=0.5433‒0.8102, P=0.014) for uric acid and Hcy levels, respectively.

Conclusion

The clinical phenotype of MOGAD varies in patients of different ages. The most common disease spectrum was ADEM in patients aged&lt;18 years, while optic neuritis was commonly found in patients aged ≥18 years. The uric acid and Hcy levels are risk factors for the severity of neurological dysfunction at disease onset in patients with first-attack MOGAD.

Clinical and neuroimaging findings in MOGAD-MRI and OCT

Myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGAD) are rare in both children and adults, and have been recently suggested to be an autoimmune neuroinflammatory group of disorders that are different from aquaporin-4 autoantibody-associated neuromyelitis optica spectrum disorder and from classic multiple sclerosis. In-vivo imaging of the MOGAD patient central nervous system has shown some distinguishing features when evaluating magnetic resonance imaging of the brain, spinal cord and optic nerves, as well as retinal imaging using optical coherence tomography. In this review, we discuss key clinical and neuroimaging characteristics of paediatric and adult MOGAD. We describe how these imaging techniques may be used to study this group of disorders and discuss how image analysis methods have led to recent insights for consideration in future studies.

Comparative study of AQP4 antibody-related diseases and MOG antibody-related diseases among the population in Hunan, China

To compare the clinical, imaging, and prognostic characteristics of AQP4 antibody-related diseases and MOG antibody-related diseases. The clinical data of 56 AQP4 antibody-positive patients and 14 MOG antibody-positive patients in the Second Xiangya Hospital of Central South University from June 2016 to June 2019 were collected. 92.9% of the patients with positive AQP4 antibody were females and 64.3% of patients with positive MOG antibody were females (P = 0.004). Patients with positive AQP4 antibody were more likely to have limb movement (P < 0.001) or limb sensory dysfunction (P < 0.001), and were more likely to have limb twitching (P = 0.036). In addition, AQP4 antibody-positive patients were more likely to have positive ANA (P = 0.013) and SSA antibody (P = 0.029), Ro-52 antibody (P = 0.047), immunoglobulin (P = 0.007), thyroid antibody (P = 0.007), abnormal C3 (P = 0.011), abnormal C4 (P = 0.014) than MOG antibody-positive patients. The involvement rate of head in MOG antibody-positive patients was higher than AQP4 antibody-positive patients (P = 0.029). The severity of clinical symptoms in AQP4-positive patients was usually more serious than that in MOG-positive patients (P < 0.001). The residual neurological deficit after treatment in AQP4-positive group was usually more serious than that in MOG-positive group (P < 0.001). AQP4 antibody-positive patients had a higher prevalence in women than MOG antibody-positive patients, and AQP4 antibody-positive patients were more likely to have spinal cord involvement symptoms and connective tissue antibody abnormalities. The EDSS score of them were higher than that of MOG antibody-positive patients after treatment, and the prognosis was worse.

Relapse activity in the chronic phase of anti-myelin-oligodendrocyte glycoprotein antibody-associated disease

Objective

The patterns of relapse and relapse-prevention strategies for anti-myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) are not completely investigated. We compared the patterns of relapse in later stages of MOGAD with those of anti-aquaporin-4 antibody (AQP4-Ab)-positive neuromyelitis optica spectrum disorder (NMOSD).

Methods

In this observational, comparative cohort study, 66 patients with MOGAD and 90 with AQP4-Ab-positive NMOSD were enrolled. We compared the patterns of relapse and annualized relapse rates (ARRs) in the first 10 years from disease onset, stratified by relapse-prevention treatments.

Results

Approximately 50% of the patients with MOGAD experienced relapses in the first 10 years. Among those not undergoing relapse-prevention treatments, ARRs in the first 5 years were slightly lower in MOGAD patients than in AQP4-Ab-positive NMOSD patients (MOGAD vs. AQP4-Ab NMOSD: 0.19 vs. 0.30; p = 0.0753). After 5 years, the ARR decreased in MOGAD patients (MOGAD vs. AQP4-Ab NMOSD: 0.05 vs. 0.34; p = 0.0001), with a 72% reduction from the first 5 years (p = 0.0090). Eight (61.5%) of the 13 MOGAD patients with more than 10-year follow-up from disease onset showed relapse 10 years after onset. Clustering in the timing and phenotype of attacks was observed in both disease patients. The effectiveness of long-term low-dose oral PSL for relapse prevention in patients with MOGAD has not been determined.

Conclusions

The relapse risk in patients with MOGAD is generally lower than that in patients with AQP4-Ab-positive NMOSD, especially 5 years after onset. Meanwhile, relapses later than 10 years from onset are not rare in both diseases.

Comparisons of clinical phenotype, radiological and laboratory features, and therapy of neuromyelitis optica spectrum disorder by regions: update and challenges

Neuromyelitis optica spectrum disorder (NMOSD) is an inflammatory demyelinating disease of the central nervous system (CNS) associated with autoantibody (ab) to aquaporin-4 (AQP4). There is obvious variation between regions and countries in the epidemiology, clinical features and management in NMOSD. Based on published population-based observation and cohort studies, the different clinical pattern of NMOSD has been seen in several geographical regions and some of these patients with NMOSD-like features do not fully meet the current diagnostic criteria, which is needed to consider the value of recently revised diagnostic criteria. At present, all treatments applied in NMOSD have made great progress, however, these treatments failed in AQP4 ab negative and refractory patients. Therefore, it is necessary to turn into an innovative idea and to open a new era of NMOSD treatment to develop novel and diverse targets and effective therapeutic drugs in NMOSD and to conduct the trails in large clinical samples and case-control studies to confirm their therapeutic effects on NMOSD in the future, which still remain a challenge.

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

To evaluate the clinical characteristics of optic neuritis (ON) with different phenotypes. This prospective study recruited patients with new-onset ON between January 2015 and March 2017 who were followed-up for 3 years. They were divided into the myelin oligodendrocyte glycoprotein-seropositive (MOG-ON), aquaporin-4-seropositive (AQP4-ON), and double-seronegative (seronegative-ON) groups, and their clinical characteristics and imaging findings were evaluated and compared. Two-hundred-eighty patients (405 eyes) were included (MOG-ON: n = 57, 20.4%; AQP4-ON: n = 98, 35.0%; seronegative-ON: n = 125, 44.6%). The proportion of eyes with best-corrected visual acuity > 20/25 at the 3-year follow-up was similar between the MOG-ON and seronegative-ON groups; the proportion in both groups was higher than that in the AQP4-ON group (p < 0.001). Relapse rates were higher in the MOG-ON and AQP4-ON groups than in the seronegative-ON group (p < 0.001). Average retinal nerve fiber layer (RNFL) thickness at 3 years was similar between the MOG-ON and AQP4-ON groups (63.41 ± 13.39 and 59.40 ± 11.46 μm, p = 0.476) but both were thinner than the seronegative-ON group (74.06 ± 11.14 μm, p < 0.001). Macular ganglion cell-inner plexiform layer (GCIPL) revealed the same pattern. Despite RNFL and GCIPL thinning, the MOG-ON group’s outcome was as favorable as that of the seronegative-ON group, whereas the AQP4-ON group showed unsatisfactory results.

Optic neuritis classification in 2021

Optic neuritis (ON) can be associated with inflammatory disease of the central nervous system or can be isolated, with or without relapse. It can also be associated with infectious or systemic disease. These multiple associations based on a variety of clinical, radiological, and biological criteria that have changed over time have led to overlapping phenotypes: a single ON case can be classified in several ways simultaneously or over time. As early, intensive treatment is often required, its diagnosis should be rapid and precise. In this review, we present the current state of knowledge about diagnostic criteria for ON aetiologies in adults and children, we discuss overlapping phenotypes, and we propose a homogeneous classification scheme. Even if distinctions between typical and atypical ON are relevant, their phenotypes are largely overlapping, and clinical criteria are neither sensitive enough, nor specific enough, to assure a diagnosis. For initial cases of ON, clinicians should perform contrast enhanced MRI of the brain and orbits, cerebral spinal fluid analysis, and biological analyses to exclude secondary infectious or inflammatory ON. Systematic screening for MOG-IgG and AQP4-IgG IgG is recommended in children but is still a matter of debate in adults. Early recognition of neuromyelitis optica spectrum disorder, MOG-IgG-associated disorder, and chronic relapsing idiopathic optic neuritis is required, as these diagnoses require therapies for relapse prevention that are different from those used to treat multiple sclerosis.