Diagnosis and classification of optic neuritis

Diagnostic Utility of Kappa Free Light Chain Index in Adults With Inaugural Optic Neuritis

BACKGROUND AND OBJECTIVES

A simple, quick, and reproducible procedure for distinguishing multiple sclerosis (MS), myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), and neuromyelitis optica spectrum disorder (NMOSD) at inaugural optic neuritis (ION) could be highly valuable in guiding early management.

METHODS

We included all adults admitted to the MS center of Marseille for ION between March 2016 and April 2024, with CSF analysis including the kappa free light chain (K-FLC) index. Receiver operating characteristic curves were used to measure the diagnostic ability of the K-FLC index.

RESULTS

Two hundred twenty-seven adults were admitted for ION; 210 (93%) had a K-FLC index measurement. MS was diagnosed in 84 (40%); clinically isolated syndrome suggestive of MS in 77 (36.5%), including 20 with future conversion to MS (CISwc); MOGAD in 26 (12.5%); NMOSD in 13 (6%); and other inflammatory disorders in 10 (5%). A K-FLC index ≥6.7 differentiated MS/CISwc from other diagnoses with specificity 86% and sensitivity 95% (area under the curve [AUC] 0.94). A K-FLC index <4.9 differentiated MOGAD from other diagnoses with specificity 63% and sensitivity 92% (AUC 0.78) and MOGAD from MS/CISwc with specificity 96% and sensitivity 92% (AUC 0.97). Among all patients, 93 (44%) had a K-FLC index <4.9: 24 of these (26%) had MOGAD and 5 (5.5%) MS/CISwc. Among the remaining patients with a K-FLC index ≥4.9 (n = 117), 2 (1.7%) had MOGAD (K-FLC index of 7.9 and 16.2) and 99 (85%) MS/CISwc. Among patients with normal MRI (n = 96), 73 (76%) had a K-FLC index <4.9: 22 of these (30%) had MOGAD, and none showed conversion to MS. Among the remaining patients with a K-FLC index ≥4.9 (n = 23), 2 (8.5%) had MOGAD and 7 (30.5%) showed conversion to MS. The K-FLC index did not differentiate NMOSD from other diagnoses and only moderately differentiated NMO from MS/CISwc (AUC 0.80).

DISCUSSION

The K-FLC index is an accessible biomarker to guide early diagnosis in patients with ION. The probability of MOGAD in patients with ION and a K-FLC index ≥4.9 is low even in case of normal brain/spinal cord MRI.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that for patients with ION, the K-FLC index can distinguish between MS/CISwc and MOGAD.

Added value of optic nerve lesions for multiple sclerosis diagnostic criteria

BACKGROUND

Optic neuritis is a frequent initial presentation of multiple sclerosis (MS). It has been suggested that optic nerve lesions on magnetic resonance imaging (MRI) should be considered as an additional lesion location for the demonstration of dissemination in space (DIS) in diagnostic criteria for MS. However, the potential value of optic nerve lesion(s) in MS diagnostic criteria has not yet been sufficiently investigated.

METHODS

We prospectively included 79 patients presenting with the first clinical event suggestive of MS. All patients underwent neurological work-up, visual-evoked potential (VEP) testing, cerebrospinal fluid (CSF) analysis and contrast-enhanced MRI of the brain, spinal cord and optic nerves (ON). Patients were classified results according to the McDonald 2017 criteria, the MAGNIMS criteria and alternative criteria considering ON imaging findings for both DIS and dissemination in time (DIT).

RESULTS

69 patients (87%) fulfilled DIS according to the MAGNIMS criteria, 67 patients (85%) according to McDonald 2017 and 70 patients (89%) according to the alternative diagnostic criteria. Including contrast enhancing ON lesions as an additional criterion for DIT and disregarding CSF results led to n = 9 (11%) additional patients fulfilling DIT and receiving the diagnosis MS compared to the McDonald 2017 and MAGNIMS criteria. Considering CSF findings in addition to MRI, 68 patients received the diagnosis of MS according to McDonald 2017 compared to 66 patients according to MAGNIMS and 69 patients according to the alternative criteria. Regarding VEP findings as an objective finding of optic nerve involvement, 67 patients had DIS according to MAGNIMS criteria and 71 patients had DIS according to alternative criteria.

CONCLUSIONS

Diagnostic criteria including ON lesion on MRI lead only to a slightly higher sensitivity but lower specificity regarding the diagnosis of MS.

Diagnostic accuracy of inter-eye difference of ganglion cell layer alone in identifying optic neuritis in multiple sclerosis

INTRODUCTION

The 2024 McDonald criteria for diagnosing multiple sclerosis (MS) include optic nerve involvement as a fifth region for establishing dissemination in space. Optic neuritis (ON) can be detected through optical coherence tomography (OCT) using an inter-eye absolute or percentage difference (IEAD, IEPD) in ganglion cell-inner plexiform layer (GCIPL) thickness.

OBJECTIVE

To compare the diagnostic accuracy of GCIPL IEAD/IEPD with GCL and IPL IEAD/IEPD alone for identifying a history of ON.

METHODS

This cross-sectional retrospective study included people with MS (pwMS) who underwent an OCT scan. Diagnostic accuracy was assessed using ROC analysis.

RESULTS

A total of 241 pwMS (mean age 34.7 years [SD 9.7], 70.1% female) were included. Sixty-eight (28.2%) patients had a documented history of unilateral ON. GCL IEAD (AUC 0.79, cut-off ⩾ 0.06 mm3 or ⩾2µm, 58.9% sensitivity, 85.1% specificity) and IEPD (AUC 0.80, cut-off ⩾ 3%, 48.7% sensitivity, 89.8% specificity) demonstrated excellent diagnostic accuracy for unilateral ON, showing non-inferiority to the established GCIPL IEAD/IEPD.

CONCLUSION

GCL IEAD and IEPD provide strong diagnostic accuracy for identifying unilateral ON and can be effectively used as an alternative to GCIPL IEAD/IEPD to facilitate implementation in clinical routine.

MOG35 - 55-induced EAE model of optic nerve inflammation compared to MS, MOGAD and NMOSD related subtypes of human optic neuritis

Optic neuritis (ON), or inflammation of the optic nerve, is a common presenting symptom of demyelinating neuroinflammatory conditions that result in significant, subacute vision loss. Given its association with visual impairment and varying extent of visual recovery, ON has been recognized as a significant health burden with a need for new therapeutic strategies to improve long-term visual outcomes. Among the resources utilized to study ON, animal models have emerged as powerful tools to examine the underlying pathophysiology and the effectiveness of proposed therapies. In the current review, we discuss the functional and structural phenotypes related to ON in currently used mouse models, and summarize how the pathophysiology and visual phenotype of the myelin oligodendrocyte glycoprotein 35-55 (MOG35 - 55) experimental autoimmune encephalomyelitis (EAE) mouse model recapitulates clinical features of multiple sclerosis (MS), myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), and neuromyelitis optica spectrum disorder (NMOSD). The location of ON and the amount of visual recovery in the EAE model most closely resembles MS and NMOSD. However, we propose that the MOG35 - 55-induced EAE model of ON is primarily a MOGAD model given its similarity in pathophysiology, spinal cord demyelination pattern, and the degree of vision loss, retinal nerve fiber layer (RNFL) swelling, and disc edema. Overall, the MOG35 - 55-induced EAE animal model demonstrates overlapping features of autoimmune demyelinating conditions and serves as a comprehensive tool to further our understanding of visual impairment in all three conditions.

Incidence of optic neuritis among Afro-descendant, a cohort study

BACKGROUND

Optic neuritis (ON) is a multifactorial condition with a strong association with ethnicity.

OBJECTIVES

We conducted a retrospective cohort study in a Caribbean Island, Martinique, French West Indies to assess the incidence and characteristics of ON among an Afro-descendant (AD) population.

METHODS

We reviewed medical records of all patients presenting ON at the Fort de France University Hospital, Martinique between 2018 and 2022. We analysed clinical, paraclinical, and biological examinations at onset and during follow-up (6 months, 1, 2 and 3 years). ON was confirmed after a neuro-ophthalmological evaluation according to the latest criteria defined in the Lancet, 2022.

RESULTS

Overall, 44 patients with a condition suggestive of ON were evaluated, out of which 29 fulfilled the criteria for ON. The overall incidence was 1.61 (95% CI: 1.12-2.08) per 100,000 person-years. The final diagnosis was distributed as follows: neuromyelitis optica spectrum disorder (NMOSD) (10%), myelin oligodendrocyte glycoprotein (MOG) ON (20%), multiple sclerosis (35%), single isolated ON (24%), relapsing isolated ON (7%) and (4%) unclassified diagnosis.

CONCLUSION

This is the first cohort study assessing the incidence of ON and its characteristics among AD. We found a high proportion of severe disease, such as NMOSD and MOG-associated disease.

Optic Neuropathies

OBJECTIVE

This article highlights the clinical features, evaluation, and management of optic neuropathies commonly encountered in clinical practice.

LATEST DEVELOPMENTS

Optic neuropathies encompass all conditions affecting the optic nerve, including those caused by ischemia, inflammation (including infections and autoimmune causes), elevated intracranial pressure, compression and infiltration, toxins, nutritional deficiencies, and hereditary diseases. Surgical and medical treatments targeting the specific causes of optic neuropathies are rapidly expanding, such as surgical options to address papilledema in patients with elevated intracranial pressure and the development of gene therapies for hereditary optic neuropathies. These advances underscore the importance of swift and accurate assessments to identify the cause of optic nerve dysfunction. The evaluation of the patient with an optic neuropathy begins with a careful history and examination. Signs of optic nerve dysfunction include decreased visual acuity, color vision impairment, a relative afferent pupillary defect in the affected eye, and visual field deficits. Neuroimaging of the orbits is one of the most useful tests in determining the cause of an optic neuropathy. Additional diagnostic testing and the formulation of a treatment plan should be guided by the differential diagnosis.

ESSENTIAL POINTS

Optic neuropathies are often misdiagnosed because of errors in eliciting or interpreting the history and physical examination. A systematic approach to identifying the clinical manifestations distinctive to specific optic neuropathies is imperative for directing diagnostic assessments, formulating tailored treatment regimens, and identifying broader central nervous system and systemic disorders.

Optic Neuritis

OBJECTIVE

This article reviews the most common and noteworthy inflammatory and infectious optic neuropathies, with an update on newer syndromes.

LATEST DEVELOPMENTS

We have entered an era of antibody-assisted definitions of distinct types of optic neuritis, including aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein-associated disease, with distinct pathophysiologies, prognoses, and management options. It is crucial to distinguish between these entities and other common inflammatory (eg, sarcoid or other granulomatous inflammation) or infectious optic neuropathies as appropriate therapy radically differs. These developments highlight the increasing importance of precision terminology as many of these now distinctly defined syndromes have been previously lumped together as "typical or atypical optic neuritis." An individualized evaluation and treatment approach is required.

ESSENTIAL POINTS

Multiple sclerosis-related optic neuritis is the most common form of inflammatory demyelinating optic neuritis, causing short segments of optic nerve inflammation, with an excellent visual prognosis and tendency to improve with or without high-dose steroids.Aquaporin-4 associated optic neuritis causes longitudinally extensive optic nerve inflammation and has a more guarded prognosis for visual recovery, with poor visual outcomes in untreated patients compared with multiple sclerosis or myelin oligodendrocyte glycoprotein-associated disease.Myelin oligodendrocyte glycoprotein optic neuritis also causes longitudinally extensive optic nerve inflammation with a predilection for optic disc edema and tends to be very steroid sensitive, but recurrent. Infectious optic neuropathies are important to recognize; syphilis incidence has doubled in the last decade and requires early aggressive therapy to maximize visual recovery.

Review of atypical optic neuritis

Optic neuritis (ON), an inflammatory optic neuropathy, is among the most common causes of visual loss. In its initial clinical appearance, ON may have unilateral or bilateral presentation, and anterior (papillitis) or retrobulbar localization. Traditionally, cases are divided into typical and atypical ON. In the Western hemisphere, most typical cases of optic nerve inflammation are associated with multiple sclerosis (MS). However, ON may also be associated with a series of disorders of known or initially undetected origin. Atypical ON has a somewhat different clinical picture from typical ON, and encompasses neuromyelitis optica spectrum disease (NMOSD), myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), idiopathic recurrent neuroretinitis (NR), chronic relapsing inflammatory ON (CRION), ON within systemic autoimmune diseases, paraneoplastic and neuritis during or after infectious diseases or vaccination. The causes should be meticulously worked up, to address the therapeutic and prognostic challenges posed by these conditions. Here, we provide a brief overview of atypical ON, as encountered in our clinical practice, and additionally discuss the possible occurrence of optic neuropathies other than inflammatory and other ocular diseases within these disorders.

Practical issues concerning the use of optical coherence tomography in multiple sclerosis in Latin America: Discussion from 19 centres on behalf of the Foro Latam EM study group

The 2024 McDonald Criteria now include the optic nerve as the fifth topography for dissemination in space. Optical coherence tomography (OCT) is a valuable biomarker for the diagnosis, prognosis and monitoring of multiple sclerosis (MS). A panel of MS neurologists from 19 centres across 9 Latin American (LATAM) countries discussed OCT use, access, standardized protocols and research potential. They found inequities in OCT access between private (80%) and public healthcare (44%). Only 9 centres had standardized protocols, 50% of which followed the OSCAR-IB consensus criteria for retinal OCT quality assessment and 53% had a neuro-ophthalmologist. The panel concluded that OCT should be available in all MS centres and that standardized acquisition and reporting, as well as improved knowledge of OCT use, in clinical practice are necessary. OCT has significant research potential in LATAM that requires further development and implementation.

Case report: Coexistence of optic neuritis and primary anti-PLA2R-positive membranous nephropathy

BACKGROUND

Optic neuritis (ON) is an inflammatory optic neuropathy characterized by acute vision loss. Primary anti-PLA2R-positive membranous nephropathy, an autoimmune disease, has been reported to be related to neurological diseases. However, the co-occurrence of ON and primary membranous nephropathy (PMN) has not been reported.

CASE PRESENTATION

A 57-year-old male presented with acute bilateral vision loss. Laboratory tests indicated proteinuria, hypoalbuminemia, hyperlipidemia, and a significantly increased level of anti-phospholipase A2 receptor antibody (PLA2RAb). Orbital MRI revealed inflammatory changes in the posterior segments of both optic nerves. Following treatments with corticosteroids and immunosuppressants, there was a significant improvement in the patient's vision and proteinuria.

CONCLUSION

This case suggests that early identification and intervention for multisystem autoimmune damages are crucial for improving patient prognosis.

Early Macular Ganglion Cell Loss in Leber Hereditary Optic Neuropathy, an Optical Coherence Tomography Biomarker to Differentiate Optic Neuritis

Background/Objectives: Leber hereditary optic neuropathy (LHON) is often misdiagnosed in its early stages as idiopathic single isolated optic neuritis (SION) or multiple-sclerosis-associated optic neuritis (MS-ON) due to the young age of the patients, the subacute vision loss, and the central visual field defect. The aim of this retrospective study was to evaluate changes in the peripapillary RNFL and GCLT over time in patients with early LHON, MS-ON, and SION in order to differentiate Leber hereditary optic neuropathy (LHON) from optic neuritis (ON) in the early stages of the disease. Methods: Patients with LHON and ON (either idiopathic single isolated optic neuritis (SION) or ON as the first symptom of relapsing-remitting multiple sclerosis (MS-ON) were included. Optical coherence tomography (OCT) scans were reviewed. The inclusion criteria were at least one follow-up OCT examination and a definite diagnosis after examination. Changes in the peripapillary retinal nerve fibre layer (RNFL) and macular ganglion cell layer thickness (GCLT) in both groups were evaluated over time and compared with normative data. The analysis focused on the early phase (0-45 days) after symptom onset. Results: Nine LHON patients with early OCT scans and twenty patients with ON were included. Quantitative OCT analysis showed greater RNFL swelling in LHON compared to ON during the first 60 days after symptom onset. Between day 61 and day 120, subnormal RNFL values were observed in both groups compared to controls. Thereafter, the RNFL decreased continuously and severely in the LHON group. The RNFL of ON patients did not show a clear progression after day 120. The GCLT in five LHON eyes showed a strong and solid decrease from day 0 to day 45, which was stronger than the moderate atrophy measured in ON eyes. Continuous GCL atrophy was measured until day 121 in LHON, after which a floor effect was reached. The GCLT in the inner nasal and inner inferior sectors was significantly smaller in LHON compared to ON patients on days 0-45. Conclusions: Thinning of the GCLT occurs at an early stage in LHON patients. Thus, GCLT may become a diagnostic tool to differentiate LHON from ON in the early phase of disease.

Optic Neuritis Presentation and Outcomes: A Single-Center Experience From Northern Saudi Arabia

Objectives This study aimed to analyze the demographic characteristics, clinical presentation, and treatment outcomes of patients with optic neuritis (ON) at King Khalid Hospital, Hail, Saudi Arabia. Methods A retrospective cohort study was conducted reviewing medical records of 40 patients diagnosed with ON between January 2021 and December 2024. Data collected included demographics, clinical presentations, neurological findings, imaging results, and treatment outcomes. Results The study population was predominantly female (n = 32, 80%), Saudi nationals (n = 33, 82.5%), and young adults aged 16-26 years (n = 24, 60%). Most cases were either idiopathic (n = 21, 52.5%) or associated with multiple sclerosis (MS) (n = 18, 45%), with a predominantly unilateral presentation (n = 37, 92.5%). Common symptoms included blurred vision (n = 38, 95.0%) and color vision changes (n = 31, 77.5%). Initial visual acuity was less than 20/200 in (n = 20, 50%) of cases. IV steroids were the primary treatment (n = 31, 77.5%), and (n = 32, 80%) of patients achieved vision better than 20/200 post-treatment. Significant associations were found between vision outcomes and both initial visual acuity (p = 0.011) and symptom duration (p = 0.041). Conclusions This study demonstrates generally favorable outcomes for patients with ON in the Hail region, with early presentation and treatment associated with better visual outcomes. The demographic and clinical patterns observed align with international literature while providing specific insights into the regional manifestation of the condition.

Changes in the Incidence of Optic Neuritis before and after the Coronavirus Disease 2019 Outbreak: A Nationwide Study 2017-2022

PURPOSE

To determine the risk of optic neuritis (ON) during nonpharmaceutical interventions (NPI), vaccination, and infection phases of the coronavirus disease 2019 (COVID-19) pandemic in comparison with levels before the outbreak in pediatric and adult populations in South Korea.

DESIGN

A nationwide, population-based retrospective study.

PARTICIPANTS

South Korean individuals with a primary diagnosis of ON received between January 2017 and December 2022.

METHODS

The Korean Health Insurance Review and Assessment database was queried for new diagnoses of ON between January 2017 and December 2022. Data were divided into 4 periods: before COVID-19 (2017-2019), NPI (2020), nationwide vaccination (2021), and nationwide infection (2022). The risk of ON development for each period was calculated and compared with levels before COVID-19, with 95% confidence intervals (CIs) reported.

MAIN OUTCOME MEASURES

Incidence rate ratio (IRR) of ON for each period.

RESULTS

A total of 7216 patients (52.7% female patients) were included in the study, with patients receiving a diagnosis of ON as follows: 3770 patients before COVID-19 (2017-2019), 1193 patients during NPI, 1135 patients during vaccination, and 1118 patients during the infection phases. The annual incidence of ON during NPI (IRR, 0.92; 95% CI, 0.85-1.00; P = 0.043), vaccination (IRR, 0.88; 95% CI, 0.81-0.95; P = 0.001), and infection (IRR, 0.86; 95% CI, 0.80-0.93; P < 0.001) phases significantly decreased compared with levels before COVID-19 when adjusted for age and sex. The proportions of diagnosis with multiple sclerosis (MS), neuromyelitis optica (NMO), and acute disseminated encephalomyelitis (ADEM) among patients in whom ON developed increased significantly in 2021 in comparison with levels before COVID-19 (10.93% vs. 6.43%; P = 0.0002).

CONCLUSIONS

The risks of ON development during the NPI, vaccination, and infection phases of COVID-19 did not increase in comparison with levels before the outbreak in the general population. However, COVID-19 vaccination may be associated with increased risks of ON associated with diseases such as ADEM, MS, and NMO.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Autoantibody profile (MOG-IgG-positivity, AQP4-IgG-positivity, and double-seronegativity) as an outcome predictor after optic neuritis

BACKGROUND

Optic neuritis (ON) is the leading cause of optic neuropathy among young adults. Approximately 45 % of these patients have autoantibodies, and their possible clinical and prognostic implications have not been completely elucidated.

OBJECTIVE

We aimed to assess the visual outcome and its predictors in a cohort of patients with optic neuritis as a clinically isolated syndrome according to their antibody profile: AQP4-IgG-positivity, MOG-IgG-positivity, and double-seronegativity (SN).

METHODS AND MATERIAL

This cohort study used partial retrospective data collection from the neuroimmunology outpatient clinic of the University of São Paulo Hospital, including consecutive cases of isolated inflammatory ON. All samples were tested for MOG and AQP4 antibodies using in-house cell-based assays in live HEK-293 cells. This study was conducted following the STROBE guidelines.

RESULTS

Forty-seven consecutive patients were included in this study. The number of patients with visual acuity (VA) worse than 20/200 during acute attacks was similar among the three groups. However, severe long-term disability (20/200) was less frequent in patients with MOG-IgG (AQP4-IgG group: 58 %, MOG-IgG group: 15 %, SN group: 54 %; p = 0.029). After adjusting for age and attack severity, MOG-IgG status was associated with a 30.9 % higher relative VA improvement (95 %CI 7.5 - 54.3 %, p = 0.011) than the other subgroups.

CONCLUSIONS

Severe visual acuity disability was less frequent in the MOG-IgG group than in the AQP4-IgG and SN groups. Positivity for these antibodies was the only predictor of long-term VA in patients with isolated ON (single or recurrent).

Isolated Optic Neuritis: Etiology, Characteristics, and Outcomes in a US Mountain West Cohort

BACKGROUND

The diagnosis and treatment of autoimmune optic neuritis (ON) has improved with the accessibility and reliability of aquaporin-4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) antibody testing, yet autoantibody-negative ON remains common. This study describes the demographic, clinical, and outcome data in patients with isolated ON across the pediatric and adult cohort.

METHODS

A retrospective chart review of University of Utah Health patients with the International Classification of Diseases ( ICD ) code of ICD-9 377.30 (ON unspecified), ICD-9 377.39 (other ON), or ICD-10 H46 (ON) and at least 2 ophthalmologic evaluations were conducted between February 2011 and July 2023. Only isolated cases of ON without other brain or spinal demyelinating lesions were evaluated. Differences in demographic and clinical characteristics between AQP4, MOG, and Other-ON were determined.

RESULTS

Of the 98 patients (15 children and 83 adults), 9 (9.2%) were positive for AQP4-IgG and 35 (35.7%) tested positive for MOG-IgG. Fifty-four were classified into Other-ON, of which 7 (13.0%) had recurrence or new demyelinating lesions during a median follow-up of 12.5 months-2 were ultimately diagnosed with recurrent isolated ON (RION), 1 with chronic relapsing inflammatory ON (CRION), 2 with multiple sclerosis, 1 with collapsin response-mediator protein (CRMP)-5-ON, and 1 with seronegative neuromyelitis optica spectrum disorder. Four patients were treated with long-term immunosuppressive therapy. No patients with RION or CRION had preceding infections; they had first recurrences of ON within 2 months. At presentation, AQP4-ON (75%) and MOG-ON (48.8%) had more severe vision loss (visual acuity <20/200) than Other-ON (23.2%, P = 0.01). At the 1-month follow-up, 93.0% of patients with MOG-ON and 89.3% of patients with Other-ON demonstrated a visual acuity ≥20/40, compared with only 50% of patients with AQP4-ON ( P < 0.01). By the last follow-up, 37.5% of the AQP4-ON still exhibited visual acuity <20/40, including 25% who experienced severe vision loss (visual acuity <20/200). By contrast, over 95% of patients with MOG-ON and Other-ON maintained a visual acuity of ≥20/40. In our cohort, over a quarter of pediatric cases presented with simultaneous bilateral ON, 40% had a preceding infection, and 44.4% initially presented with a visual acuity <20/200. Two pediatric cases had recurrence, and both were MOG-ON. By their last follow-up, all pediatric cases had achieved a visual acuity of 20/40 or better. In addition, pediatric cases were more likely to exhibit disc edema compared with adult cases (100% vs 64%, P < 0.01).

CONCLUSIONS

Despite recent advances in identification and availability of testing for AQP4-IgG and MOG-IgG, over half of patients who presented with isolated ON remained with an "idiopathic" diagnostic label. As more than 1 in 10 patients with AQP4-IgG and MOG-IgG negative ON experienced recurrence or develop new demyelinating lesions, clinicians should provide anticipatory guidance and closely monitor for potential long-term outcomes. In addition, it is crucial to re-evaluate the diagnosis in cases of poor recovery, ON recurrence, and the emergence of new neurological symptoms, as ON can often be the initial presentation of other conditions.

New optical coherence tomography biomarker for diagnosis of acute optic neuritis in multiple sclerosis

Objectives

Is imaging of retrolaminar optic nerve, during attack of acute optic neuritis in multiple sclerosis valuable?

Methods

This is a prospective observational Case series study. Twenty two patients recruited from Al-Azhar University Hospitals and Charity Eye Centre (El-Mustafa Eye Centre, Cairo); from October 2022 to February 2024. The patients were referred; as, they had developed episode of acute optic neuritis. Full ophthalmic and neurological examinations were done for all patients within 2 weeks of acute optic neuritis. Imaging of peripapillary retinal nerve fiber layer by conventional spectral domain optical coherence tomography (OCT), and retrolaminar part of optic nerve by enhanced depth imaging OCT were done for both acute optic neuritis eyes and the fellow eyes.

Results

A total of 44 eyes of 22 MS patients (18 females, 4 males) with the mean age of 30.54 ± 9.65 years were included in this study. The best corrected visual acuity (BCVA) was significantly less in the optic neuritis eyes (median = 0.30) than in the fellow eyes (median = 0.70), p = 0.007. Homogeneity of retrolaminar optic nerve tissue was altered in the optic neuritis eyes. OCT showed myelin aggregates as round or oval hyper-reflective foci in the optic neuritis eyes (95 % confidence interval: 2.90 [2.19-3.61]), that were not presented in the fellow eyes, p = 0.000.

Conclusion

Using enhanced depth imaging OCT during acute attack of optic neuritis revealed retrolaminar hyper reflective foci as a new biomarker.

Barriers in Healthcare to the Use of Optical Coherence Tomography Angiography in Multiple Sclerosis

Optical coherence tomography angiography (OCT-A) is a state-of-the-art imaging technique for the retinal vasculature to accurately segment the capillary network and assign it to retinal layers. OCT-A is a promising technique to better understand neurological diseases with visual system manifestations, such as multiple sclerosis (MS), and to identify and characterize vascular biomarkers. Initial studies suggested vascular changes in MS and its differential diagnoses such as myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) and neuromyelitis optica spectrum disorder (NMOSD). Here we review clinical and technical aspects of OCT-A imaging and discuss the potential for the MS field as well as barriers that need to be overcome before OCT-A can be established in clinical application.

The atypical faces of optic neuritis: neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein antibody-associated disease

PURPOSE OF REVIEW

The purpose of this article is to provide a review of neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), with a focus on what renders optic neuritis "atypical" in these two conditions. Clinical features, diagnostic criteria, and epidemiology are outlined. Acute treatments for optic neuritis, as well as immunotherapy for NMOSD and MOGAD are discussed.

RECENT FINDINGS

Updates in NMOSD and MOGAD are highlighted, with an emphasis on novel work including the new 2023 MOGAD diagnostic criteria, our evolving understanding on the epidemiology of these conditions, and recently FDA-approved NMOSD treatments. Pipeline therapies are also discussed.

SUMMARY

A thorough history and examination, supported by ancillary testing, continues to be the mainstay of optic neuritis diagnosis. Stratifying typical versus atypical optic neuritis is paramount. Within the atypical category, NMOSD and MOGAD are important considerations. Clues can point towards these diagnoses and guide steps for treatment, which is increasingly becoming targeted to individual diseases, as the pathophysiology is different for these disorders.

Optical coherence tomography: implications for neurology

PURPOSE OF REVIEW

This article explores the role of optical coherence tomography (OCT) in neurology practice, particularly in diagnosing and monitoring conditions such as papilledema, optic neuritis, and retinal artery occlusion. OCT has been increasingly utilized as a noninvasive and effective tool for detecting and monitoring neuroaxonal damage in the visual pathway, which is important for early intervention and improved patient outcomes across a variety of neurologic conditions.

RECENT FINDINGS

OCT as an imaging modality continues to demonstrate its utility in quantifying optic nerve and retinal changes reflecting neuroaxonal injury, including, peripapillary retinal nerve fiber layer (pRNFL) thickness and macular ganglion cell layer thickness (or volume). This review focuses on recent evidence regarding the utilization of this modality in diagnosing, monitoring, and quantifying treatment responses in patients with papilledema, optic neuritis, and retinal artery occlusion. Advances in OCT technology, including deep learning algorithms, continue to enhance the diagnostic accuracy and predictive capabilities in the field of neuro-ophthalmology.

SUMMARY

In recent years, OCT has become an essential tool in neuro-ophthalmic assessment, offering precise structural and anatomical assessments that support diagnosis, treatment planning, and monitoring of conditions affecting the visual pathway. Ongoing advances in OCT technology are expected to further enhance its clinical utility.

Ultrasonographic assessment of optic nerve: does it help in lupus-induced optic neuropathy?

OBJECTIVE

Evaluating the potential role of neuromuscular ultrasonography (NMUS) in assessing optic nerve affection in patients with systemic lupus erythematosus (SLE), compared with healthy controls and other conventional strategies in diagnosing optic neuropathy.

METHODS

We conducted an observational cross-sectional study comparing patients with SLE and a healthy group. We measured the optic nerve diameter (OND) and optic nerve sheath diameter (ONSD) and calculated the OND/ONSD ratio and side-to-side difference. An ophthalmologist examined all lupus patients and visual evoked potential (VEP) was performed to help evaluate the rule of NMUS in lupus-induced optic neuropathy.

RESULTS

In this study, we include 140 subjects, 65 lupus patients and 75 controls. Significant enlargement was present among lupus patients OND and ONSD (p= 0.017, 0.004, respectively) in comparison to controls; ultrasonographic evaluation had a high specificity when compared to ophthalmological evaluation and VEP reaching 89.6% and 88.1%, respectively, but with very low sensitivity.

CONCLUSION

Ultrasonographic evaluation of the optic nerve may add significant value to the diagnosis of optic neuropathy in patients with SLE and should be considered a complementary tool to other conventional methods.

Clinical Predictors in Acute Optic Neuritis: Analysis Based on Clinical Trial Data

PURPOSE

To identify baseline clinical predictors of visual outcomes 6 months after acute optic neuritis using data from our completed clinical neuroprotection trial: Treatment of Optic Neuritis with Erythropoietin (TONE).

DESIGN

Secondary analysis of data from the TONE study cohort (NCT01962571).

PARTICIPANTS

A total of 103 patients presenting within 10 days of a first episode of acute unilateral optic neuritis as a clinically isolated syndrome with baseline high-contrast visual acuity (HCVA) ≤20/40 Snellen (logarithm of the minimum angle of resolution 0.3). Patients were recruited from 12 German university hospitals between November 25, 2014, and October 9, 2017.

METHODS

We selected potential predictors based on literature research and experience, and then computed initial linear regression models that each included 1 predictor together with the baseline value of the outcome of interest. We used a forward-selection approach to build a multiple regression model for each outcome. Because the trial medication of the TONE study (erythropoietin) had no effect on the visual system, we used pooled (treatment-agnostic) data for all analyses.

MAIN OUTCOME MEASURES

Independent predictors of HCVA, low-contrast letter acuity, visual-evoked potential (VEP) P100 peak times, macular ganglion cell and inner plexiform layer thickness, and peripapillary retinal nerve fiber layer thickness at 6 months.

RESULTS

On multiple regression, the most consistent predictors were higher baseline HCVA, which was associated with better outcomes across all measures except VEP conduction time; male sex, which predicted worse outcomes for all measures except HCVA; and older age, which was linked to poorer functional outcomes.

CONCLUSIONS

Patients who are older, are male, and present with worse initial visual function may be at risk for worse clinical outcomes in acute optic neuritis. This knowledge may inform individual patient counseling, facilitate patient selection for time-sensitive and invasive immunomodulatory treatments, and can be used to ensure balanced risk characteristics in clinical neuroprotection trials.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Ultrasound pupillometry for the detection of a relative afferent pupillary defect (RAPD): Systematic evaluation in patients with optic neuritis and comparison with infrared video pupillometry

PURPOSE

A relative afferent pupillary defect (RAPD) is a characteristic clinical sign of optic neuritis (ON). Here, we systematically evaluated ultrasound pupillometry (UP) for the detection of an RAPD in patients with ON, including a comparison with infrared video pupillometry (IVP), the gold standard for objective pupillometry.

MATERIALS AND METHODS

We enrolled 40 patients with acute (n = 9) or past (n = 31) ON (ON+), 31 patients with multiple sclerosis (MS) without prior ON, and 50 healthy controls (HC) in a cross-sectional observational study. Examinations comprised the swinging flashlight test, B-mode UP, IVP, autorefraction to assess the best-corrected visual acuity, optical coherence tomography to determine peripapillary retinal nerve fiber layer thickness, and the 51-item National Eye Institute-Visual Function Questionnaire to determine the vision-related quality of life.

RESULTS

While UP and IVP measurements of pupil diameter (PD) at rest correlated in ON+ eyes (n = 52, r = 0.56, 95% CI: 0.35; 0.72) and in HC eyes (n = 100, r = 0.60, 95% CI: 0.47; 0.72), PD at rest was smaller in UP than in IVP measurements (difference, mean (SD) ON+ eyes: 0.44 (0.87) mm, HC eyes: 0.69 (0.80) mm). RAPD assessment by UP sharply discriminated acute ON eyes (n = 9) and HC eyes (n = 100, AUC = 1, 95%CI: 1; 1). UP detected an RAPD in 5/31 (16%) patients with MS without prior ON who had not exhibited an RAPD during the swinging flashlight test. In ON+ eyes (n = 52), UP showed stronger correlations with visual acuity (r = 0.66, 95% CI: 0.50; 0.78) and vision-related quality of life (r = 0.47, 95% CI: 0.24; 0.66) than IVP (r = 0.52, 95% CI: 0.36; 0.67 and r = 0.27, 95% CI: 0.03; 0.51).

CONCLUSIONS

B-mode UP allows for objective detection and quantification of an RAPD with performance characteristics similar to IVP. RAPD assessment by UP may detect subclinical optic nerve damage in patients with MS. We propose a standardized protocol for RAPD detection by UP that can be used in routine clinical evaluation of patients with ON or other optic neuropathies.

Biomarkers in patients with autoimmune optic neuritis not associated with multiple sclerosis: Demographic, clinical and prognostic features

BACKGROUND

The new optic neuritis (ON) classification leads to a change in how ON patients are grouped. Our aim is to appraise the clinical features and prognoses of patients with autoimmune ON not associated with MS.

METHODS

Patients referred to our neuro-ophthalmology laboratory were enrolled to this retrospective study. Patients with ON associated with MS were excluded. The remaining patients were divided into three groups: aqauaporin-4 (AQP4) antibody ON group, myelin oligodendrocyte glycoprotein (MOG) antibody ON group, and seronegative ON group. The patients were examined on admission, one month after acute treatment, and at the third-year follow-up. We compared demographic, clinical, radiologic, laboratory data, and treatment responses among these three groups.

RESULTS

The study included 92 patients. The older age of onset, bilateral simultaneous involvement of the optic nerves, severe vision loss at onset, and need for aggressive treatment were more common in the AQP-ON and the MOG-ON groups than the seronegative ON group (P = 0.01, P = 0.003, P = 0.011, P = 0.007, P < 0.001, P < 0.001, respectively). The presence of optic disc edema was a significant feature of MOG-ON as well as long-length contrast enhancement on MRI (P = 0.003, P = 0.002). Additional autoimmune antibodies and CNS lesions outside the optic nerve were the features of AQP4-ON patients (P < 0.001, P = 0.015). Generalized estimating equations analysis revealed that the presence of AQP4 antibody, increased age and recurrence were associated with visual acuity over time (P = 0.014, P = 0.002, P = 0.016, respectively).

CONCLUSION

The association of serum biomarker status with demographic, clinical features, and visual outcomes indicate the importance of biomarker detection in these patients.

Multimodal Longitudinal Optical Imaging Reveals Optic Neuritis Preceding Retinal Pathology in Experimental Autoimmune Encephalomyelitis

BACKGROUND AND OBJECTIVES

Inflammatory demyelinating diseases of the CNS, chief among them multiple sclerosis (MS), are a major cause of disability in young adults. Early manifestations of MS commonly involve visual dysfunction, which is often caused by optic neuritis and is accompanied by quantifiable structural changes of the anterior visual pathway. Retinal optical coherence tomography (OCT) has emerged as an important tool for clinical assessment of these structural alterations, but the underlying pathobiological mechanisms and temporal dynamics are yet poorly understood at a cellular level.

METHODS

Using the experimental autoimmune encephalomyelitis (EAE) model of MS in fluorescent reporter mouse strains for neuronal function and innate immune cells, we use a unique combination of retinal intravital 2-photon microscopy (2PM) and OCT. In this fashion, we elucidate the spatiotemporal interplay of functional and structural retinal changes over the course of 1 month after EAE induction, with histopathologic imaging validating main results.

RESULTS

While all mice display histologic signs of optic neuritis early after EAE induction and independently of motor symptom severity, retinal signs of neuronal stress and parenchymal immune activation spike well after clinical peak of disease, with no signs of lasting structural damage appearing within 1 month after EAE induction. Thus, local retinal endpoints appear to be functions of downstream axonal damage rather than of immediate immune activation directed at the retina. However, as early as 1 week after EAE induction, retinal 2PM can detect recruitment of perivascular immune cells towards the optic nerve (ON), providing the earliest sign of disease activity in otherwise clinically inconspicuous mice.

DISCUSSION

Our work identifies the recruitment of CX3CR1+ cells to the ON as an early sign of disease underlining the importance of combined structural and functional retinal imaging for the spatiotemporal characterization of neuroinflammatory and neurodegenerative processes. It further proposes retinal phagocyte orientation, morphology, and abundance as potential surrogate markers for neurodegenerative activity.

Usage status of biologics for the chronic treatment of optic neuritis in neuromyelitis optica spectrum disorders in Japan

PURPOSE

To investigate the usage status of biologics for the chronic treatment of optic neuritis including neuromyelitis optica spectrum disorders in Japan.

DESIGN

Multicenter retrospective case series.

METHODS

Patients diagnosed with anti-aquaporin 4 antibody (AQP4-Ab) positive optic neuritis and had been initiated on biologics (satralizumab, eculizumab, and inebilizumab) between January 2020 and August 2022 were identified at 30 facilities in Japan. These patients were investigated regarding changes in oral steroid doses, optic neuritis relapse, and adverse events after initiation of biologics.

RESULTS

Eighty-eight patients with AQP4-Ab positive optic neuritis initiated on biologics were included. Satralizumab was the most common biologic used (79 patients), followed by eculizumab (6 patients) and inebilizumab (3 patients). In the satralizumab group, during the observation period (10.0±7.0 months) until February 2023, the oral steroid dose was reduced significantly from 13.8 ± 8.6 mg/day at the time of initiation to 5.3 ± 4.8 mg/day (p < 0.001). No relapse of optic neuritis was observed in 76 of 79 patients (96.2%) after initiation of satralizumab. Furthermore, in 15 patients who succeeded in discontinuing steroids during 8.5 ± 5.8 months after initiation of satralizumab, no relapse of optic neuritis was observed throughout the observation period. Adverse events occurred in 7 patients with satralizumab and 2 patients with eculizumab, but no serious infections were observed.

CONCLUSIONS

Satralizumab was the most commonly used biologic for AQP4-Ab positive optic neuritis in Japan. This study demonstrates the efficacy and safety of satralizumab in preventing the relapse of optic neuritis.

Hyperreflective retinal foci are associated with retinal degeneration after optic neuritis in neuromyelitis optica spectrum disorders and multiple sclerosis

BACKGROUND

Hyperreflective retinal foci (HRF) visualized by optical coherence tomography (OCT) potentially represent clusters of microglia. We compared HRF frequencies and their association with retinal neurodegeneration between people with clinically isolated syndrome (pwCIS), multiple sclerosis (pwMS), aquaporin 4-IgG positive neuromyelitis optica spectrum disorder (pwNMOSD), and healthy controls (HC)-as well as between eyes with (ON+eyes) and without a history of optic neuritis (ON-eyes).

METHODS

Cross-sectional data of pwCIS, pwMS, and pwNMOSD with previous ON and HC were acquired at Charité-Universitätsmedizin Berlin. HRF analysis was performed manually on the central macular OCT scan. Semi-manual OCT segmentation was performed to acquire the combined ganglion cell and inner plexiform layer (GCIPL), inner nuclear layer (INL), and peripapillary retinal nerve fiber layer (pRNFL) thickness. Group comparisons were performed by linear mixed models.

RESULTS

In total, 227 eyes from 88 patients (21 pwCIS, 32 pwMS, and 35 pwNMOSD) and 35 HCs were included. HRF in GCIPL and INL were more frequently detected in pwCIS, pwMS, and pwNMOSD than HCs (p < 0.001 for all comparisons) with pwCIS exhibiting the greatest numbers. ON+eyes of pwMS had less HRF in GCIPL than ON-eyes (p = 0.036), but no difference was seen in pwCIS and pwNMOSD. HRF GCIPL were correlated to GCIPL thickness in ON+eyes in pwMS (p = 0.040) and pwNMOSD (p = 0.031).

CONCLUSION

HRF occur in ON+eyes and ON-eyes across neuroinflammatory diseases. In pwMS and pwNMOSD, HRF frequency was positively associated with GCIPL thickness indicating that HRF formation might be dependent on retinal ganglion cells.

Visual quality of life in NMOSD and MOGAD: profiles, dynamics and associations with ageing and vision

OBJECTIVE

In this multicentric study, we were interested in the vision-related quality of life and its association with visual impairment in neuromyelitis optica spectrum disorders (NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) in comparison to multiple sclerosis (MS) and healthy controls.

METHODS

We analysed extracted data from the German NEMOS registry including National Eye Institute Visual Function Questionnaire (NEI-VFQ) scores, high and low contrast visual acuity (HCVA, LCVA), visually evoked potentials (VEP) and the scores for the expanded disability status scale (EDSS) and other neurological tests which assessed their disease-related impairment. The mean follow-up time of our patients was 1.2 years. We used adjusted linear mixed effect models to analyse NEI-VFQ differences and interactions with visual acuity among NMOSD, MOGAD, a matched MS cohort and healthy controls.

RESULTS

Despite a younger age in the MOGAD cohort (39 y.o.), vision and socioemotional-related quality of life reduction was similar over all patient subgroups in comparison to healthy controls. The most impacted life quality dimension was general health, followed by general vision, driving and role difficulties. Decline in some of the NEI-VFQ subscales scores is mostly predicted by age. The HCVA was the best predictor for most of the subscales of the NEI-VFQ.

DISCUSSION

Despite important age differences, NMOSD, MOGAD and MS seem to share a rather similar perception on their vision and quality of life impairment, which is overall poorer than that of healthy controls.

HLA-transgenic mouse models to study autoimmune central nervous system diseases

It is known that certain human leukocyte antigen (HLA) genes are associated with autoimmune central nervous system (CNS) diseases, such as multiple sclerosis (MS), but their exact role in disease susceptibility and etiopathogenesis remains unclear. The best studied HLA-associated autoimmune CNS disease is MS, and thus will be the primary focus of this review. Other HLA-associated autoimmune CNS diseases, such as autoimmune encephalitis and neuromyelitis optica will be discussed. The lack of animal models to accurately capture the complex human autoimmune response remains a major challenge. HLA transgenic (tg) mice provide researchers with powerful tools to investigate the underlying mechanisms promoting susceptibility and progression of HLA-associated autoimmune CNS diseases, as well as for elucidating the myelin epitopes potentially targeted by T cells in autoimmune disease patients. We will discuss the potential role(s) of autoimmune disease-associated HLA alleles in autoimmune CNS diseases and highlight information provided by studies using HLA tg mice to investigate the underlying pathological mechanisms and opportunities to use these models for development of novel therapies.

Comparison between contrast-enhanced fat-suppressed 3D FLAIR brain MR images and T2-weighted orbital MR images at 3 Tesla for the diagnosis of acute optic neuritis

PURPOSE

The purpose of this study was to compare the capabilities of contrast-enhanced fat-suppressed (CE FS) three-dimensional fluid-attenuated inversion recovery (3D FLAIR) brain magnetic resonance imaging (MRI) with those of coronal T2-weighted orbital MRI obtained at 3 Tesla for the diagnosis of optic neuritis (ON).

MATERIALS AND METHODS

Patients who presented to our center with acute visual loss and underwent MRI examination of the orbits and the brain between November 2014 and February 2020 were retrospectively included. Three radiologists independently and blindly analyzed CE FS 3D FLAIR and coronal T2-weighted images. Disagreements in image interpretation were resolved by consensus with an independent neuroradiologist who was not involved in the initial reading sessions. The primary adjudication criterion for the diagnosis of ON was the presence of an optic nerve hypersignal. Sensitivity, specificity, and accuracy of CE 3D FLAIR brain images were compared with those of coronal T2-weighted orbital images using McNemar test. Artifacts were classified into three categories and compared between the two image sets.

RESULTS

A total of 1023 patients were included. There were 638 women and 385 men with a mean age of 42 ± 18.3 (standard deviation) years (age range: 6-92 years). Optic nerve hyperintensities were identified in 375/400 (94%) patients with ON using both 3D FLAIR and coronal T2-weighted images. Sensitivity, specificity, and accuracy of both sequences were 94% (95% CI: 91.3-96.1), 79% (95% CI: 75.5-82.2), and 89% (95% CI: 86.8-90.7), respectively. Optic disc hypersignal was detected in 120/400 patients (30%) using 3D FLAIR compared to 3/400 (0.75%) using coronal T2-weighted images (P < 0.001). Optic radiation hypersignal was observed in 2/400 (0.5%) patients using 3D FLAIR images. Significantly more artifacts (moderate or severe) were observed on coronal T2-weighted images (801/1023; 78%) by comparison with 3D FLAIR images (448/1023; 44%) (P < 0.001).

CONCLUSION

The performance of 3D FLAIR brain MRI for the diagnosis of ON is not different from that of coronal T2-weighted orbital MRI and its use for optic nerve analysis may be beneficial.

Neuromyelitis Optica Spectrum Disorder With Unilateral Retrobulbar Neuritis: A Case Report

Neuromyelitis optica spectrum disorder (NMOSD) includes conditions with autoimmune genesis, which are manifested by attacks of optic neuritis (ON) and transverse myelitis (TM), and also express aquaporin 4 (NMO-IgG) or myelin oligo-endocytic glycoprotein (MOGAb) antibodies. In rare cases, the disease may also have a clinical presentation with only TM, without ON or with ON, without TM. These conditions are also included in the spectrum. We present a case of a 50-year-old patient with complaints of blurry vision in the left eye, neck pain, and numbness of the hands a few months prior to hospitalization. After a consultation with an ophthalmologist, magnetic resonance imaging (MRI) of the brain was performed, and findings showed left ON. Serological findings showed antibodies for aquaporin 4 with a ratio of 1:100, which is a pathognomic marker for NMOSD. Upon admission to the clinic, the complaints persisted. The neurological status revealed decreased vision of the left eye, pain in the Valleix points in the cervical region, and hyperesthesia including dermatomes C5-C8, more prominent for the right arm. Routine blood tests showed leukocytosis, neutrophilia, and lymphocytosis. Additional virology studies were performed to rule out neuroborreliosis, neurosyphilis, and human immunodeficiency virus (HIV). MRI of the cervical spine revealed dural sac compression from degenerative spinal disease. Electromyography (EMG) showed radiculopathy at the C5-C8 levels and neuropathy of n. ulnaris sinistra and n. medianus dextra. Consultation with an ophthalmologist revealed a decrease in the left eye visus. The treatment plan consisted of methylprednisolone 1000 mg for five days and gastroprotection with famotidine 40 mh p.o. Further consultations with the ophthalmologist were done in the following days to monitor the visual status of the patient. After completion of the diagnostic and treatment plan, slight recovery of the visus and reversal of the pain symptomatology was reported. Based on the history, clinical findings, ophthalmologic examination, brain and neck imaging (MRI), and laboratory results (NMO-IgG ratio 1:100 ), NMOSD with left retrobulbar neuritis (Devic's disease) was concluded as the final diagnosis. Multiple sclerosis (MS; retrobulbar neuritis) first attack, systemic connective tissue disease (systemic lupus erythematosus, Sjögren's syndrome, and antiphospholipid syndrome), and neuro-infection were discussed. Clinical suspicion of intracranial tumors was ruled out. Corticosteroids and gastroprotectors were prescribed for oral use under the supervision of a neurologist. Regular check-ups were performed. The reported case of NMOSD with unilateral optic nerve involvement is a rare condition in neurological practice. It requires an individualized approach to diagnose and apply treatment. Patient follow-up is a key starting point toward gathering more information about autoimmune processes in the central nervous system (CNS) and toward finding faster, more reliable, and cheaper clinical and instrumental methods of diagnosis, which in turn may lead to more timely initiation of treatment, proportionally leading to improvement in the patient's quality of life.

The Role of Artificial Intelligence in Predicting Optic Neuritis Subtypes From Ocular Fundus Photographs

BACKGROUND

Optic neuritis (ON) is a complex clinical syndrome that has diverse etiologies and treatments based on its subtypes. Notably, ON associated with multiple sclerosis (MS ON) has a good prognosis for recovery irrespective of treatment, whereas ON associated with other conditions including neuromyelitis optica spectrum disorders or myelin oligodendrocyte glycoprotein antibody-associated disease is often associated with less favorable outcomes. Delay in treatment of these non-MS ON subtypes can lead to irreversible vision loss. It is important to distinguish MS ON from other ON subtypes early, to guide appropriate management. Yet, identifying ON and differentiating subtypes can be challenging as MRI and serological antibody test results are not always readily available in the acute setting. The purpose of this study is to develop a deep learning artificial intelligence (AI) algorithm to predict subtype based on fundus photographs, to aid the diagnostic evaluation of patients with suspected ON.

METHODS

This was a retrospective study of patients with ON seen at our institution between 2007 and 2022. Fundus photographs (1,599) were retrospectively collected from a total of 321 patients classified into 2 groups: MS ON (262 patients; 1,114 photographs) and non-MS ON (59 patients; 485 photographs). The dataset was divided into training and holdout test sets with an 80%/20% ratio, using stratified sampling to ensure equal representation of MS ON and non-MS ON patients in both sets. Model hyperparameters were tuned using 5-fold cross-validation on the training dataset. The overall performance and generalizability of the model was subsequently evaluated on the holdout test set.

RESULTS

The receiver operating characteristic (ROC) curve for the developed model, evaluated on the holdout test dataset, yielded an area under the ROC curve of 0.83 (95% confidence interval [CI], 0.72-0.92). The model attained an accuracy of 76.2% (95% CI, 68.4-83.1), a sensitivity of 74.2% (95% CI, 55.9-87.4) and a specificity of 76.9% (95% CI, 67.6-85.0) in classifying images as non-MS-related ON.

CONCLUSIONS

This study provides preliminary evidence supporting a role for AI in differentiating non-MS ON subtypes from MS ON. Future work will aim to increase the size of the dataset and explore the role of combining clinical and paraclinical measures to refine deep learning models over time.

Improved MR Detection of Optic Nerve Demyelination With MP2RAGE-FLAWS Compared With T2-Weighted Fat-Saturated Sequences

OBJECTIVES

Nonenhanced T1-w sequences such as magnetization-prepared 2 rapid acquisition gradient echo (MP2RAGE) and derived fluid and white matter suppression (FLAWS) have demonstrated high performance for detecting brain parenchymal and cervical spine demyelinating lesions in multiple sclerosis. However, their potential for identifying optic nerve (ON) demyelination remains unexplored. The aim of this study was to evaluate the performance of compressed sensing-accelerated (CS) MP2RAGE-FLAWS imaging for detection of ON demyelination lesions compared with T2-w fat-saturated (FS) TSE imaging in a clinical setting.

MATERIALS AND METHODS

We conducted a retrospective study of magnetic resonance scans acquired on patients with central nervous system demyelinating disorders between January and December 2022. Inclusion criteria were the acquisition in the same session of a brain CS-MP2RAGE-FLAWS imaging and a combination of axial + coronal T2-w FS orbital sequences. A 4-step radiological analysis-including blinded and consensus readings-assessed ON lesion detection. The reference standard was the final reading session of radiologists using the entire patient file. Sensitivities and specificities of both sequences were computed and compared using McNemar χ2 tests.

RESULTS

Thirty-nine patients (mean age: 43 ± 14 years; 25 women) were analyzed, including 34 with multiple sclerosis, 2 with MOGAD (myelin oligodendrocyte glycoprotein antibody-associated disease), 1 with NMOSD (neuromyelitis optica spectrum disorder), and 2 with indeterminate demyelinating disease. Among the 78 ONs analyzed, 64 lesions were detected with CS-MP2RAGE-FLAWS as opposed to 37 with 2D T2-w FS imaging, corresponding to a total of 41 and 27 affected nerves, respectively. CS-MP2RAGE-FLAWS exhibited higher sensitivity for overall detection of ON lesions compared with 2D T2-w FS imaging (97.5% vs 67.5%, P = 0.001) without reducing the specificity. Improved lesion detectability with CS-MP2RAGE-FLAWS was significant compared with 2D T2-w FS in intraorbital and intracanalicular segments (respectively, 92.3% vs 50% and 96.3% vs 66.7%; P < 0.05). There was no difference in sensitivity (P = 0.69) or specificity (P = 0.99) regarding the intracranial segment analysis.

CONCLUSIONS

CS-MP2RAGE-FLAWS sequence improves ON lesion detection compared with conventional 2D T2-w FS, especially in the intraorbital segment, while simultaneously providing whole-brain and cervical spinal cord imaging at no additional time cost.

Glaucoma: what the neurologist needs to know

Glaucoma is a progressive optic neuropathy resulting from pathological changes at the optic disc due to elevated intraocular pressure. Its diagnosis, treatment and follow-up are almost entirely conducted in ophthalmology clinics, with screening conducted by community optometrists. Despite this, neurologists may encounter glaucoma in both its acute presentation (as angle closure, presenting as acute headache) and its chronic forms (often as optic neuropathy of unknown cause). An awareness of the underlying pathological process, and the key distinguishing signs and symptoms, will allow neurologists to identify the glaucomatous process rapidly. Timely referral is essential as glaucoma invariably results in progressive visual loss without treatment. This review therefore condenses the wide field of glaucoma into a practical summary, aimed at practitioners with limited clinical experience of this ophthalmic condition.

Correlations Between Disability Score, Optical Coherence Tomography and Microperimetry in Patients with Multiple Sclerosis

Purpose

To characterize ocular motility disturbances through Microperimetry (MP) in patients with Multiple Sclerosis (MS) trying to detect those capable of influencing the disability to improve the accuracy of assessing visual impact in EDSS scale. MP results were compare with some structural parameters obtained by OCT.

Patients and Methods

Cross-sectional analytical and correlational case-control study approved by Ethical Committee. A total of 82 eyes (41 patients) and 30 healthy eyes (15 subjects) were enrolled after informed consent. All participants underwent ophthalmological evaluation with MP and OCT. Variables included MS disease duration, Expanded Disability Status Scale (EDSS) score; in OCT: central macular thickness (CMT), ganglion cell-inner plexiform layer thickness (GCIPL), and peripapillary retinal nerve fiber layer thickness (pRNFL); and in MP: test duration, reaction time, average macular threshold (AT), and 4 fixation stability indexes (P1, P2, BCEA63, BCEA95).

Results

MS group showed a significant decrease in GCIPL (p < 0.001) and pRNFL thickness (p < 0.001) compared to the control group. Furthermore, patients demonstrated a longer examination (p < 0.001) and reaction (p < 0.001) times, reduced AT (p < 0.001), more unstable fixation indexes (P1 p <0.004, P2 p = 0.018, BCEA63 p = 0.005 and BCEA95 p = 0.007), measured by MP. In addition, patients with a history of ON (n=16) demonstrated longer examination times in MP (p = 0.049) compared to MS patients without ON, but they were not correlations with OCT measurements, EDSS score correlated with the CMT (p = 0.023, r = -0.25), MP duration (p = 0.043, r = 0.22), and fixation indexes (P1 p = 0.049, r = -0.22, BCEA63 p = 0.041, r = 0.23, BCEA95 p = 0.049, r = 0.22).

Conclusion

Our study emphasizes the complementary utility of MP and OCT in assessing MS patients. Additionally, it highlights that using MP for objective measurements of oculomotor dysfunction could improves accuracy in disability assessment on the EDSS scale.

Diagnostic Value of Inter-Eye Difference Metrics on OCT for Myelin Oligodendrocyte Glycoprotein Antibody-Associated Optic Neuritis

BACKGROUND AND OBJECTIVES

The 2022 International Consortium for Optic Neuritis diagnostic criteria for optic neuritis (ON) include optical coherence tomography (OCT). The diagnostic value of intereye difference (IED) metrics is high for ON in patients with multiple sclerosis and aquaporin-4 antibody seropositive neuromyelitis optica spectrum disorders, but unknown in myelin oligodendrocyte glycoprotein antibody-associated ON (MOG-ON).

METHODS

A multicenter validation study was conducted on the published IED cutoff values (>4% or >4 μm in the macular ganglion cell and inner plexiform layer [mGCIP] or >5% or >5 μm in the peripapillary retinal nerve fiber layer [pRNFL]) in individuals with MOG-ON and age-matched and sex-matched healthy controls (HCs). Structural data were acquired with Spectralis spectral-domain OCT >6 months after ON. We calculated sensitivity, specificity, and receiver operating characteristics for both intereye percentage (IEPD) and absolute difference (IEAD).

RESULTS

A total of 66 individuals were included (MOG-ON N = 33; HCs N = 33). ON was unilateral in 20 and bilateral in 13 subjects. In the pooled analysis, the mGCIP IEPD was most sensitive (92%), followed by the mGCIP IEAD (88%) and pRNFL (84%). The same pattern was found for the specificity (mGCIP IEPD 82%, IEAD 82%; pRNFL IEPD 82%, IEAD 79%).In subgroup analyses, the diagnostic sensitivity was higher in subjects with unilateral ON (>99% for all metrics) compared with bilateral ON (61%-78%).

DISCUSSION

In individuals with MOG-ON, the diagnostic accuracy of OCT-based IED metrics for ON was high, especially of mGCIP IEPD.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that the intereye difference on OCT can distinguish between those with MOG and normal controls.

Macular vascular density alteration patterns in paediatric optic neuritis patients with serum MOG antibody positivity detected by optic coherence tomography angiography

PURPOSE

The retinal microvascular network plays a crucial role in inflammatory injury in paediatric optic neuritis (PON) with serum MOG antibody positivity (MOG + PON). This study compared retinal microvascular densities and structural alterations in MOG + PON eyes with paediatric isolated optic neuritis (PION) eyes and followed up with the final best-corrected visual acuity (BCVA) after 6 months.

METHODS

A total of 29 children (52 eyes) with PON, including 15 MOG + PON cases (28 eyes), 6 PION cases (10 eyes), 2 neuromyelitis optica spectrum disorders associated PON(NMOSD-PON) cases (4 eyes), 6 MOG-associated disease (MOGAD) patients without ON-affected eyes (MOG + NPON) cases (10 eyes) and age- and gender-matched healthy controls (HCs) underwent superficial/deep retinal angiography density (SAD/DAD) by optical coherence tomography angiography (OCTA). Their BCVAs were followed up until 6 months after PON onsets.

RESULTS

MOG + PON cases had better final BCVAs than PION and NMOSD-ON. MOG + PON (35.7 ± 10.3 %) and PION (40.1 ± 10.3 %) eyes experienced severe SAD reductions in contrast to MOGAD+NPON (48.7 ± 5.2 %) and HCs eyes (55.6 ± 8.2 %). However, DAD in MOG + PON eyes (48.5 ± 9.2 %) and MOG + NPON eyes (53.1 ± 3.3 %) increased compared to HC eyes (45.7 ± 9.6 %; p = 0.028 and 0.009, respectively). SAD reduction occurred in acute PON and was detected as early as 2 weeks after PON onset.

CONCLUSIONS

MOG + PON eyes had better final BCVAs than PION eyes, which displayed superficial retinal microvascular perfusion reductions and deep microvascular perfusion increases. SAD could be a sensitive surrogate for PON attacks in children with MOGAD.

Misdiagnosis of Multiple Sclerosis: Past, Present, and Future

PURPOSE OF REVIEW

Misdiagnosis of multiple sclerosis (MS) is a prevalent worldwide problem. This review discusses how MS misdiagnosis has evolved over time and focuses on contemporary challenges and potential strategies for its prevention.

RECENT FINDINGS

Recent studies report cohorts with a range of misdiagnosis between 5 and 18%. Common disorders are frequently misdiagnosed as MS. Overreliance on MRI findings and misapplication of MS diagnostic criteria are often associated with misdiagnosis. Emerging imaging biomarkers, including the central vein sign and paramagnetic rim lesions, may aid diagnostic accuracy when evaluating patients for suspected MS. MS misdiagnosis can have harmful consequences for patients and healthcare systems. Further research is needed to better understand its causes. Concerted and novel educational efforts to ensure accurate and widespread implementation of MS diagnostic criteria remain an unmet need. The incorporation of diagnostic biomarkers highly specific for MS in the future may prevent misdiagnosis.

Accuracy of Diagnosing Optic Neuritis Using DANTE T1-SPACE Imaging

Purpose

To evaluate the use of delay alternating with nutation for tailored excitation-prepared T1-weighted turbo spin echo (DANTE T1-SPACE) imaging for diagnosing optic neuritis and to analyze its correlation with clinical findings before and after treatment.

Patients and Methods

Patients diagnosed with optic neuritis or non-arteritic anterior ischemic optic neuropathy (NA-AION) were evaluated at the Ophthalmology Department of Kyoto University Hospital. All patients underwent magnetic resonance (MR) studies before treatment initiation and ophthalmic examinations before and after treatment. Three ophthalmologists independently reviewed the MR scans for abnormalities. The magnetic resonance imaging (MRI) assessments included post-contrast DANTE T1-SPACE, post-contrast volumetric interpolated breath-hold examination (VIBE), and short T1 inversion recovery (STIR) scans. The presence of abnormalities in each sequence was determined.

Results

Of 36 eyes from 30 patients, 21 eyes from 17 patients were diagnosed with optic neuritis, and 15 eyes from 13 patients were diagnosed with NA-AION. DANTE T1-SPACE sequences showed better sensitivity for detecting optic neuritis than STIR sequences (100% vs 67%, p = 0.009). VIBE images did not confirm enhancement of lesions in some cases with optic neuritis. No differences were observed among the sequences for NA-AION. Lesion length evaluated by DANTE T1-SPACE sequences was associated with circumpapillary retinal nerve fiber layer thickness at the initial visit, eye pain, and the time interval from symptom onset to MRI scan.

Conclusion

Contrast-enhanced DANTE T1-SPACE was better than other sequences of MRI for diagnosing optic neuritis.

Differential diagnosis of suspected multiple sclerosis: global health considerations

The differential diagnosis of multiple sclerosis can present specific challenges in patients from Latin America, Africa, the Middle East, eastern Europe, southeast Asia, and the Western Pacific. In these areas, environmental factors, genetic background, and access to medical care can differ substantially from those in North America and western Europe, where multiple sclerosis is most common. Furthermore, multiple sclerosis diagnostic criteria have been developed primarily using data from North America and western Europe. Although some diagnoses mistaken for multiple sclerosis are common regardless of location, a comprehensive approach to the differential diagnosis of multiple sclerosis in Latin America, Africa, the Middle East, eastern Europe, southeast Asia, and the Western Pacific regions requires special consideration of diseases that are prevalent in those locations. A collaborative effort has therefore assessed global differences in multiple sclerosis differential diagnoses and proposed recommendations for evaluating patients with suspected multiple sclerosis in regions beyond North America and western Europe.

The influence of MOGAD on diagnosis of multiple sclerosis using MRI

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is an immune-mediated demyelinating disease that is challenging to differentiate from multiple sclerosis (MS), as the clinical phenotypes overlap, and people with MOGAD can fulfil the current MRI-based diagnostic criteria for MS. In addition, the MOG antibody assays that are an essential component of MOGAD diagnosis are not standardized. Accurate diagnosis of MOGAD is crucial because the treatments and long-term prognosis differ from those for MS. This Expert Recommendation summarizes the outcomes from a Magnetic Resonance Imaging in MS workshop held in Oxford, UK in May 2022, in which MS and MOGAD experts reflected on the pathology and clinical features of these disorders, the contributions of MRI to their diagnosis and the clinical use of the MOG antibody assay. We also critically reviewed the literature to assess the validity of distinctive imaging features in the current MS and MOGAD criteria. We conclude that dedicated orbital and spinal cord imaging (with axial slices) can inform MOGAD diagnosis and also illuminate differential diagnoses. We provide practical guidance to neurologists and neuroradiologists on how to navigate the current MOGAD and MS criteria. We suggest a strategy that includes useful imaging discriminators on standard clinical MRI and discuss imaging features detected by non-conventional MRI sequences that demonstrate promise in differentiating these two disorders.

Recognizing Leber's Hereditary Optic Neuropathy to avoid delayed diagnosis and misdiagnosis

Leber's Hereditary Optic Neuropathy (LHON) is a maternally inherited optic nerve disease primarily caused by mutations in mitochondrial DNA (mtDNA). The peak of onset is typically between 15 and 30 years, but variability exists. Misdiagnosis, often as inflammatory optic neuritis, delays treatment, compounded by challenges in timely genetic diagnosis. Given the availability of a specific treatment for LHON, its early diagnosis is imperative to ensure therapeutic appropriateness. This work gives an updated guidance about LHON differential diagnosis to clinicians dealing also with multiple sclerosi and neuromyelitis optica spectrtum disorders-related optic neuritis. LHON diagnosis relies on clinical signs and paraclinical evaluations. Differential diagnosis in the acute phase primarily involves distinguishing inflammatory optic neuropathies, considering clinical clues such as ocular pain, fundus appearance and visual recovery. Imaging analysis obtained with Optical Coherence Tomography (OCT) assists clinicians in early recognition of LHON and help avoiding misdiagnosis. Genetic testing for the three most common LHON mutations is recommended initially, followed by comprehensive mtDNA sequencing if suspicion persists despite negative results. We present and discuss crucial strategies for accurate diagnosis and management of LHON cases.

Abnormal dynamic features of spontaneous brain activity and their concordance in neuromyelitis optica spectrum disorder related optic neuritis: A resting-state fMRI study

OBJECTIVE

Characterizing the neuropathological features of neuromyelitis optica spectrum disorder-related optic neuritis (NMOSD-ON) is crucial for understanding its mechanisms. Given the important role of dynamic features in the brain's functional architecture, we aim to investigate the dynamic features of spontaneous brain activity and their concordance using resting-state functional magnetic resonance imaging (rs-fMRI) in NMOSD-ON.

METHODS

Fourteen NMOSD-ON patients and 21 healthy controls (HCs) underwent rs-fMRI and ophthalmological examinations. Five dynamic indices depicting different aspects of functional characteristics were calculated using a sliding window method based on rs-fMRI data. Kendall's coefficient was utilized to measure concordance among these indices at each time point. The differences of dynamic features between two groups were evaluated using two-sample t-tests, with correlations explored between altered dynamics and clinical parameters.

RESULTS

Compared to HCs, NMOSD-ON patients exhibited significant decreases in dynamic regional homogeneity (dReHo) and dynamic degree centrality (dDC) in visual regions, including bilateral cuneus, lingual gyrus, calcarine sulcus, and occipital gyrus. Conversely, increases were observed in left insula, left thalamus, and bilateral caudate. The concordance of NMOSD-ON patients was significantly lower than HCs. The dReHo of right cuneus negatively correlated with mean deviation of visual field (r = -0.591, p = 0.026) and the dReHo of left cuneus negatively correlated with disease duration (r = -0.588, p = 0.030).

CONCLUSION

The evidence suggests that regional dynamic functional alterations involving vision, emotional processing, and cognitive control may provide a new understanding of brain changes in the progression of NMOSD-ON.

Microcystic Macular Edema Caused by Non-Glaucomatous Optic Atrophy: A Single-Center, Retrospective, Cohort Study in France

Optic Atrophy (OA) can be associated with the development of microcystic macular edema (MME) in the perifoveal retinal inner nuclear layer (INL). We aimed here to retrospectively determine the prevalence of MME in patients with non-glaucomatous OA in our tertiary ophthalmology department between 2015 and 2020. We then examined how MME affected the thicknesses of the different retinal layers and the differences in demographic and clinical characteristics between those patients who developed MME and those who did not. A total of 643 eyes (429 patients) were included (mean age 45.9 ± 17.8 years, 52% female). MME developed in 95 (15%) eyes and across all etiologies of OA except for toxic/nutritional causes, but the prevalence of MME varied between the different etiologies. The development of MME was associated with thinning of the ganglion cell layer (11.0 vs. 9.6 μm; p = 0.001) and the retinal nerve fiber layer (10.1 vs. 9.15 μm; p = 0.024), with INL thickening in the 3- and 6-mm diameter areas of the central fovea. Patients developing MME had significantly worse distance best-corrected visual acuity than those not developing MME (0.62 vs. 0.38 logMAR; p = 0.002). Overall, the presence of MME in OA cannot be used to guide the diagnostic work-up of OA.

Application of the international criteria for optic neuritis in the Acute Optic Neuritis Network

OBJECTIVE

The first international consensus criteria for optic neuritis (ICON) were published in 2022. We applied these criteria to a prospective, global observational study of acute optic neuritis (ON).

METHODS

We included 160 patients with a first-ever acute ON suggestive of a demyelinating CNS disease from the Acute Optic Neuritis Network (ACON). We applied the 2022 ICON to all participants and subsequently adjusted the ICON by replacing a missing relative afferent pupillary defect (RAPD) or dyschromatopsia if magnetic resonance imaging pathology of the optical nerve plus optical coherence tomography abnormalities or certain biomarkers are present.

RESULTS

According to the 2022 ICON, 80 (50%) patients were classified as definite ON, 12 (7%) patients were classified as possible ON, and 68 (43%) as not ON (NON). The main reasons for classification as NON were absent RAPD (52 patients, 76%) or dyschromatopsia (49 patients, 72%). Distribution of underlying ON etiologies was as follows: 78 (49%) patients had a single isolated ON, 41 (26%) patients were diagnosed with multiple sclerosis, 25 (16%) patients with myelin oligodendrocyte glycoprotein antibody-associated disease, and 15 (9%) with neuromyelitis optica spectrum disorder. The application of the adjusted ON criteria yielded a higher proportion of patients classified as ON (126 patients, 79%).

INTERPRETATION

According to the 2022 ICON, almost half of the included patients in ACON did not fulfill the requirements for classification of definite or possible ON, particularly due to missing RAPD and dyschromatopsia. Thorough RAPD examination and formal color vision testing are critical to the application of the 2022 ICON.

Cerebrospinal fluid neurofilament light chain in acute optic neuritis and its predictive ability of multiple sclerosis

BACKGROUND

Studies on the capability of cerebrospinal fluid neurofilament light chain (cNfL) to predict multiple sclerosis (MS) conversion in clinically isolated syndromes have yielded varying results.

OBJECTIVES

To expand our understanding of cNfL in optic neuritis (ON) and investigate whether incorporating cNfL into the 2017 McDonald criteria could accelerate the diagnosis of MS in patients with ON.

METHODS

cNfL was measured in diagnostic samples from 74 patients with verified ON. MS was diagnosed using the 2017 McDonald criteria with a minimum observation time of two years from ON onset.

RESULTS

20.5% of 44 MS-converters did not fulfil the 2017 McDonald criteria at ON onset. A doubling of cNfL was associated with 207% (74%-514%) higher odds of MS (p = 0.00042, adjusted for age). Fulfilment of ≥ 1 MRI criterion for dissemination in space (DIS) and presence of brain contrast-enhancing lesions were associated with higher cNfL. Furthermore, cNfL correlated with inter-eye differences in retinal nerve fiber layer (RNFL) thickness (Spearman's ρ = 0.46, p = 8 × 10-5). Incorporating cNfL ≥ 906 pg/mL as a substitute for either dissemination in time or one MRI criterion for DIS increased the sensitivity (90.9% vs. 79.6%) and accuracy (91.9% vs. 87.8%), but also reduced the specificity (93.3% vs. 100%) of the 2017 McDonald criteria.

CONCLUSION

cNfL was related to MS diagnostic parameters and the degree of RNFL swelling. Clinical use of cNfL may aid in identification of ON patients with increased risk of MS until larger studies have elaborated on the potential loss of specificity if used diagnostically.

Current and future role of MRI in the diagnosis and prognosis of multiple sclerosis

In the majority of cases, multiple sclerosis (MS) is characterized by reversible episodes of neurological dysfunction, often followed by irreversible clinical disability. Accurate diagnostic criteria and prognostic markers are critical to enable early diagnosis and correctly identify patients with MS at increased risk of disease progression. The 2017 McDonald diagnostic criteria, which include magnetic resonance imaging (MRI) as a fundamental paraclinical tool, show high sensitivity and accuracy for the diagnosis of MS allowing early diagnosis and treatment. However, their inappropriate application, especially in the context of atypical clinical presentations, may increase the risk of misdiagnosis. To further improve the diagnostic process, novel imaging markers are emerging, but rigorous validation and standardization is still needed before they can be incorporated into clinical practice. This Series article discusses the current role of MRI in the diagnosis and prognosis of MS, while examining promising MRI markers, which could serve as reliable predictors of subsequent disease progression, helping to optimize the management of individual patients with MS. We also explore the potential of new technologies, such as artificial intelligence and automated quantification tools, to support clinicians in the management of patients. Yet, to ensure consistency and improvement in the use of MRI in MS diagnosis and patient follow-up, it is essential that standardized brain and spinal cord MRI protocols are applied, and that interpretation of results is performed by qualified (neuro)radiologists in all countries.

Retinal Changes in Double-Antibody Seronegative Neuromyelitis Optica Spectrum Disorders

BACKGROUND AND OBJECTIVES

To systematically describe the clinical picture of double-antibody seronegative neuromyelitis optica spectrum disorders (DN-NMOSD) with specific emphasis on retinal involvement.

METHODS

Cross-sectional data of 25 people with DN-NMOSD (48 eyes) with and without a history of optic neuritis (ON) were included in this study along with data from 25 people with aquaporin-4 antibody seropositive neuromyelitis optica spectrum disorder (AQP4-NMOSD, 46 eyes) and from 25 healthy controls (HCs, 49 eyes) for comparison. All groups were matched for age and sex and included from the collaborative retrospective study of retinal optical coherence tomography (OCT) in neuromyelitis optica (CROCTINO). Participants underwent OCT with central postprocessing and local neurologic examination and antibody testing. Retinal neurodegeneration was quantified as peripapillary retinal nerve fiber layer thickness (pRNFL) and combined ganglion cell and inner plexiform layer thickness (GCIPL).

RESULTS

This DN-NMOSD cohort had a history of [median (inter-quartile range)] 6 (5; 9) attacks within their 5 ± 4 years since onset. Myelitis and ON were the most common attack types. In DN-NMOSD eyes after ON, pRNFL (p < 0.001) and GCIPL (p = 0.023) were thinner compared with eyes of HCs. Even after only one ON episode, DN-NMOSD eyes already had considerable neuroaxonal loss compared with HCs. In DN-NMOSD eyes without a history of ON, pRNFL (p = 0.027) and GCIPL (p = 0.022) were also reduced compared with eyes of HCs. However, there was no difference in pRNFL and GCIPL between DN-NMOSD and AQP4-NMOSD for the whole group and for subsets with a history of ON and without a history of ON-as well as between variances of retinal layer thicknesses.

DISCUSSION

DN-NMOSD is characterized by severe retinal damage after ON and attack-independent retinal neurodegeneration. Most of the damage occurs during the first ON episode, which highlights the need for better diagnostic markers in DN-NMOSD to facilitate an earlier diagnosis as well as for effective and early treatments. In this study, people with DN-NMOSD presented with homogeneous clinical and imaging findings potentially suggesting a common retinal pathology in these patients.

Value of Optic Nerve MRI in Multiple Sclerosis Clinical Management: A MAGNIMS Position Paper and Future Perspectives

The optic nerve is frequently involved in multiple sclerosis (MS). However, MRI of the optic nerve is considered optional in the differential diagnosis of optic neuropathy symptoms either at presentation or in established MS. In addition, unlike spinal cord imaging in comparable scenarios, no role is currently recommended for optic nerve MRI in patients presenting with optic neuritis for its confirmation, to plan therapeutic strategy, within the MS diagnostic framework, nor for the detection of subclinical activity in established MS. In this article, evidence related to these 3 aspects will be summarized and gaps in knowledge will be highlighted, including (1) the acquisition challenges and novel sequences that assess pathologic changes within the anterior visual pathways; (2) the clinical implications of quantitative magnetic resonance studies of the optic nerve, focusing on atrophy measures, magnetization transfer, and diffusion tensor imaging; and (3) the relevant clinical studies performed to date. Finally, an algorithm for the application of optic nerve MRI will be proposed to guide future studies aimed at addressing our knowledge gaps.