Clinical Characteristics of Pediatric Optic Neuritis With Myelin Oligodendrocyte Glycoprotein Seropositive: A Cohort Study

Clinico-radiologic Spectrum and Outcome of Pediatric Acquired Demyelinating Disorders of Central Nervous System: A Retrospective Indian Tertiary Care Hospital Cohort

BACKGROUND

 Pediatric acquired demyelinating syndrome (ADS) constitutes a group of treatable disorders with acute neurologic dysfunction. Neuroimaging has played a significant role in diagnosis of ADS. We describe clinico-radiologic spectrum, outcomes, and comparison of the groups: acute disseminated encephalomyelitis (ADEM), neuromyelitis optica spectrum disorder (NMOSD), clinically isolated syndrome (CIS), multiple sclerosis (MS), and myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGAD).

METHODS

 Retrospective review of 70 children with ADS at a tertiary care hospital over 15 years (2008-2023) was performed. Diagnosis was assigned as per International Pediatric Multiple Sclerosis Study Group criteria 2016. Fisher's exact and chi-square tests were applied.

RESULTS

 Thirty-nine boys and 31 girls aged 8.2 ± 4.0 years with CIS (n = 27), ADEM (n = 16), NMOSD (n = 13), MS (n = 1), and MOGAD (n = 13) were included. Clinical syndromes with positive significant association included polyfocal symptoms, encephalopathy in ADEM, optic neuritis (ON) in MOGAD, brainstem, area postrema syndrome in NMOSD. MOGAD presented with atypical presentations like prolonged fever (PF; 76.9%) and aseptic meningitis (23%). Seropositivity for myelin oligodendrocyte glycoprotein immunoglobulin-G was 62% and for NMO-IgG 2.6%. Neuroimaging of MOGAD showed lesions predominantly in basal ganglia/thalami (69.2%), optic nerve (46.2%), and cerebellum (46.2%). Imaging patterns between ADEM and MOGAD were comparable except for more ON (p = 0.004), spinal cord (p = 0.01), and cerebellar lesions (p = 0.03) in MOGAD. Area postrema lesion was unique to NMOSD. All patients received immunotherapy, of whom 91.4% (n = 64) had good recovery, 8.6% (n = 6) had functional limitation on modified Rankin scale at discharge, and 12 (17.1%) relapsed.

CONCLUSION

 The largest group was CIS. Seropositivity of MOG was high with atypical presentations like PF and aseptic meningitis. Specific neuroimaging patterns correlated with ADS categories. Short-term outcome with immunotherapy was favorable in spite of relapses.

Clinical outcomes and Anti-MOG antibodies in pediatric optic neuritis: A prospective observational study

OBJECTIVES

The objective of this study was to look at the clinical outcomes, and to determine the proportion of children with visual recovery after the first demyelinating event of optic neuritis (ON).

METHODOLOGY

In this observational study, children with the first clinical event of optic neuritis at an age less than 18 years were evaluated. High-contrast visual acuity, colour vision, Expanded Disability Status Scale (EDSS), Anti-MOG and AQP-4 antibodies were assessed.

RESULTS

Of the 55 screened, 45 children (77 eyes), median age-98 months, 30 (67%) bilateral were enrolled. Fifty of 77 eyes (67%) had Snellen visual acuity less than 6/60. Twelve children (27%) were MOG seropositive and 3 had AQP-4 positivity. At median follow up of 35 months, 10 (22%) children had one or more relapses. At follow up, the median (IQR) visual acuity improved from nadir of 2.1 (1-2.7) logMAR to 0 (0-0.18) logMAR and 64/77 eyes (83%) had visual recovery. The diagnosis at last follow up was isolated ON in 39/45 (86.6%), relapsing ON (5, 11%), AQP-4 positive NMOSD (3, 7%), MOG antibody associated demyelination (12, 27%), dual seronegative ON (30,67%) and Multiple sclerosis (1, 2%).

CONCLUSIONS

Most children with first demyelinating event as ON have a monophasic illness. Despite severe acute-phase visual loss, most eyes with ON will recover good visual functions. The risk of AQP-4 disease and multiple sclerosis is low in this group.

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

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

Pediatric Neuromyelitis Optica Spectrum Disorder

Neuromyelitis Optica Spectrum Disorder (NMOSD) is a demyelinating disease with a high relapse rate and risk of disability accrual. The condition is an astrocytopathy, with antibodies to the aquaporin-4 (AQP4) water channel being detected in AQP4-IgG seropositive disease. Presentation is uncommon in the pediatric age range, accounting for about 3%-5% of cases. NMOSD is more prevalent in populations of Black or East Asian ancestry. Core clinical syndromes include optic neuritis, acute myelitis, area postrema syndrome, acute brainstem syndrome, acute diencephalic syndrome, and symptomatic cerebral syndrome. First-line treatment options in pediatrics include rituximab, azathioprine, and mycophenolate mofetil. Over half of children with AQP4-IgG seropositive NMOSD develop permanent disability, particularly in visual and motor domains. Novel therapeutic targets in the adult population have been developed and are changing the treatment landscape for this disorder.

Attack phenotypes and disease course in pediatric MOGAD

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an autoimmune demyelinating condition that affects children differently than adults. We performed a literature review to assess the presentation and clinical course of pediatric MOGAD. The most common initial phenotype is acute disseminated encephalomyelitis, especially among children younger than five years, followed by optic neuritis (ON) and/or transverse myelitis. Approximately one-quarter of children with MOGAD have at least one relapse that typically occurs within three years of disease onset and often includes ON, even if ON was not present at onset. Clinical risk factors for a relapsing course have not been elucidated.

Characteristics of Optic Neuritis in South Korean Children and Adolescents: A Retrospective Multicenter Study

Purpose

To analyze the clinical characteristics and prognosis of optic neuritis (ON) in pediatric patients aged <19 years in South Korea.

Methods

This multicenter retrospective cohort study included 127 pediatric patients (median age: 10.3 (IQR: 7.3–14.2) years; female, 62.2%) who experienced ON for the first time between January 2004 and January 2018, with data obtained from five tertiary university-based hospitals in Korea. When ON was bilateral, the worse eye was selected for analysis. The baseline clinical characteristics and prognoses of patients, as well as the associations between these parameters, were analyzed.

Results

The baseline clinical characteristics of the patients were as follows: best-corrected visual acuity (BCVA) < 20/200, 65.9%; pain on eye movement, 47.2%; optic disc swelling, 66.9%; and bilateral involvement, 41.7%. Among 101 patients who were followed up for ≥6 months, 48 (47.5%), 12 (11.9%), 19 (18.8%), 13 (12.9%), and 9 (8.9%) had been diagnosed with isolated ON, recurrent ON, multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), and acute disseminated encephalomyelitis (ADEM)-related ON, respectively. At the latest visit, 81.9% and 71.1% had achieved BCVA of ≥20/40 and ≥ 20/25, respectively. Only disc swelling at presentation was associated with poor baseline BCVA (coefficient: 0.31, P=0.004) and greater improvement in BCVA (coefficient: 0.49, P = 0.001P=0.001); there were no significant associations between the baseline factors and final BCVA.

Conclusions

This study demonstrated pediatric ON-related clinical characteristics and visual outcomes in South Korea. Within this cohort, in about 40.6% of patients, ON was associated with other demyelinating diseases, namely, MS, NMOSD, and ADEM.

Optical Coherence Tomography in Chronic Relapsing Inflammatory Optic Neuropathy, Neuromyelitis Optica and Multiple Sclerosis: A Comparative Study

Purpose: To examine the optical coherence tomography (OCT) features of the retina in patients with chronic relapsing inflammatory optic neuropathy (CRION) and compare them with those of neuromyelitis optica spectrum disorder (NMOSD), relapsing-remitting multiple sclerosis (RRMS) with and without optic neuritis (ON), and healthy controls (HC). Methods: In this retrospective cross-sectional study, we used spectral domain OCT to evaluate the retinal structure of 14 participants with CRION, 22 with NMOSD, 40 with RRMS with unilateral ON, and 20 HC. The peripapillary retinal nerve fiber layer (pRNFL), total macular volume (TMV), and papillomacular bundle (PMB) were measured, and intra-retinal segmentation was performed to obtain the retinal nerve fiber (RNFL), ganglion cell (GCL), inner plexiform (IPL), inner nuclear (INL), outer plexiform (OPL) and outer nuclear (ONL) layer volumes. Results: The global pRNFL [39.33(±1.8) µm] and all its quadrants are significantly thinner in CRION compared with all other groups (p < 0.05). CRION patients have decreased volumes of TMV, RNFL, GCL, and IPL compared with all other groups (p < 0.05). Conclusion: Severe thinning in pRNFL and thinning in intra-retinal segments of IPL, GCL, RNFL, and TMV could be helpful in differentiating CRION from NMOSD and RRMS.

Machine learning classification of multiple sclerosis in children using optical coherence tomography

BACKGROUND

In children, multiple sclerosis (MS) is the ultimate diagnosis in only 1/5 to 1/3 of cases after a first episode of central nervous system (CNS) demyelination. As the visual pathway is frequently affected in MS and other CNS demyelinating disorders (DDs), structural retinal imaging such as optical coherence tomography (OCT) can be used to differentiate MS.

OBJECTIVE

This study aimed to investigate the utility of machine learning (ML) based on OCT features to identify distinct structural retinal features in children with DDs.

METHODS

This study included 512 eyes from 187 (n_eyes = 374) children with demyelinating diseases and 69 (n_eyes = 138) controls. Input features of the analysis comprised of 24 auto-segmented OCT features.

RESULTS

Random Forest classifier with recursive feature elimination yielded the highest predictive values and identified DDs with 75% and MS with 80% accuracy, while multiclass distinction between MS and monophasic DD was performed with 64% accuracy. A set of eight retinal features were identified as the most important features in this classification.

CONCLUSION

This study demonstrates that ML based on OCT features can be used to support a diagnosis of MS in children.

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.

The Pediatric Optic Neuritis Prospective Outcomes Study – Two-Year Results

PURPOSE

Pediatric optic neuritis (ON) is a rare disease that has not been well characterized. The Pediatric ON Prospective Outcomes Study (PON1) was the first prospective study to our knowledge aiming to evaluate visual acuity (VA) outcomes, including VA, recurrence risk, and final diagnosis 2 years after enrollment.

DESIGN

Nonrandomized observational study at 23 pediatric ophthalmology or neuro-ophthalmology clinics in the United States and Canada.

PARTICIPANTS

A total of 28 (64%) of 44 children initially enrolled in PON1 (age 3-<16 years) who completed their 2-year study visit.

METHODS

Participants were treated at the investigator's discretion.

MAIN OUTCOMES MEASURES

Age-normal monocular high-contrast VA (HCVA). Secondary outcomes included low-contrast VA (LCVA), neuroimaging findings, and final diagnoses.

RESULTS

A total of 28 participants completed the 2-year outcome with a median enrollment age of 10.3 years (range, 5-15); 46% were female, and 68% had unilateral ON at presentation. Final 2-year diagnoses included isolated ON (n = 11, 39%), myelin oligodendrocyte glycoprotein-associated demyelination (n = 8, 29%), multiple sclerosis (MS) (n = 4,14%), neuromyelitis optica spectrum disease (NMOSD) (n = 3, 11%), and acute disseminated encephalomyelitis (n = 2, 7%). Two participants (7%; 95% confidence interval [CI], 1-24) had subsequent recurrent ON (plus 1 participant who did not complete the 2-year visit); all had MS. Two other participants (7%) had a new episode in their unaffected eye. Mean presenting HCVA was 0.81 logarithm of the minimum angle of resolution (logMAR) (∼20/125), improving to 0.14 logMAR (∼20/25^-2) at 6 months, 0.12 logMAR (∼20/25^-2) at 1 year, and 0.11 logMAR (20/25^-1) at 2 years (95% CI, -0.08 to 0.3 [20/20⁺¹-20/40^-1]). Twenty-four participants (79%) had age-normal VA at 2 years (95% CI, 60-90); 21 participants (66%) had 20/20 vision or better. The 6 participants without age-normal VA had 2-year diagnoses of NMOSD (n = 2 participants, 3 eyes), MS (n = 2 participants, 2 eyes), and isolated ON (n = 2 participants, 3 eyes). Mean presenting LCVA was 1.45 logMAR (∼20/500^-2), improving to 0.78 logMAR (∼20/125⁺²) at 6 months, 0.69 logMAR (∼20/100⁺¹) at 1 year, and 0.68 logMAR (∼20/100⁺²) at 2 years (95% CI, 0.48-0.88 [20/50⁺¹-20/150^-1]).

CONCLUSIONS

Despite poor VA at presentation, most children had marked improvement in VA by 6 months that was maintained over 2 years. Associated neurologic autoimmune diagnoses were common. Additional episodes of ON occurred in 5 (18%) of the participants (3 relapses and 2 new episodes).

Long-Term Evaluation and Normal Tissue Complication Probability (NTCP) Models for Predicting Radiation-Induced Optic Neuropathy after Intensity-Modulated Radiation Therapy (IMRT) for Nasopharyngeal Carcinoma: A Large Retrospective Study in China

Purpose

To quantify the long-term evaluation of optic chiasma (OC) and/or optic nerve(s) (ONs) and to develop predictive models for radiation-induced optic neuropathy (RION) in nasopharyngeal carcinoma after intensity-modulated radiotherapy (IMRT).

Methods and Materials

A total of 3,662 patients' OC/ONs with full visual acuity and dosimetry data between 2010 and 2015 were identified. Critical dosimetry predictors of RION were chosen by machine learning and penalized regression for survival. A nomogram containing dosimetry and clinical variables was generated for predicting RION-free survival.

Results

The median follow-up was 71.79 (2.63–120.9) months. Sixty-six eyes in 51 patients (1.39%) developed RION. Two patients were visual field deficient, and 49 patients had visual acuity of less than 0.1 (20/200). The median latency time was 36 (3–90) months. The 3-, 5-, and 8-year cumulative incidence of RION was 0.78%, 1.19%, and 1.97%, respectively. Dmax was the most critical dosimetry variable for RION (AUC: 0.9434, the optimal cutoff: 64.48 Gy). Patients with a Dmax ≥64.48 Gy had a significantly higher risk of RION (HR = 102.25; 95%CI, 24.86–420.59; P < 0.001). Age (>44 years) (HR = 2.234, 95% CI = 1.233–4.051, p = 0.008), advanced T stage (T3 vs. T1-2: HR = 7.516, 95% CI = 1.725–32.767, p=0.007; T4 vs. T1-2: HR = 37.189, 95% CI = 8.796–157.266, P < 0.001), and tumor infiltration/compression of the OC/ONs (HR = 4.572, 95% CI = 1.316–15.874, p=0.017) were significant clinical risk factors of RION. A nomogram comprising age, T stage, tumor infiltration/compression of the OC/ON, and Dmax significantly outperformed the model, with only Dmax predicting RION (C-index: 0.916 vs. 0.880, P < 0.001 in the training set; 0.899 vs. 0.874, P=0.038 in the test set). The nomogram-defined high-risk group had a worse 8-year RION-free survival.

Conclusions

In the IMRT era, Dmax <60 Gy is safe and represents an acceptable dose constraint for most NPC patients receiving IMRT. A reasonable trade-off for selected patients with unsatisfactory tumor coverage due to proximity to the optic apparatus would be Dmax <65 Gy. Caution should be exercised when treating elderly and advanced T-stage patients or those with tumor infiltration/compression of the OC/ON. Our nomogram shows strong efficacy in predicting RION.

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.

The Clinical, Radiologic, and Prognostic Differences Between Pediatric and Adult Patients With Myelin Oligodendrocyte Glycoprotein Antibody-Associated Encephalomyelitis

Purpose: To evaluate the clinical differences between pediatric and adult patients with myelin oligodendrocyte glycoprotein antibody-associated encephalomyelitis (MOG-EM).

Methods: We retrospectively reviewed the clinical features of pediatric and adult patients with MOG-EM in our center between November 2015 and October 2020.

Results: Twenty-eight pediatric patients and 25 adults were admitted to our study. Bilateral optic neuritis (BON) was the most common initial phenotype in the pediatric group but less common in the adult group (28.57 vs. 0%, p = 0.0119). Almost half of the adult patients presented with neuromyelitis optica spectrum disease (NMOSD), which was less prevalent among the pediatrics (48 vs. 21.43%, p = 0.0414). Visual impairment was the most common symptom in both groups during the initial attack (pediatric group, 39.29%; adult group, 64%) and throughout the full course (pediatric group, 57.14%; adult group, 72%). More pediatric patients suffered from fever than adult patients at onset (pediatric group, 28.57%; adult group, 4%; p = 0.0442) and throughout the full course (pediatric group, 39.29%; adult group, 12%; p = 0.0245). Multiple patchy lesions in subcortical white matter (pediatric group, 40.74%; adult group, 45%), periventricular (pediatric group, 25.93%; adult group, 35%), infratentorial (pediatric group, 18.52%; adult group, 30%) and deep gray matter (pediatric group, 25.93%; adult group, 20%) were frequent in all cases, no significant difference was found between the two groups, while bilateral optic nerve involvement was more frequent in pediatric group (61.54 vs. 14.29%, p = 0.0042) and unilateral optic nerve involvement was higher in adult group (64.29 vs. 15.38%, p = 0.0052). At the last follow-up, adult patients had a higher average EDSS score (median 1.0, range 0–3) than pediatrics (median 0.0, range 0–3), though not significant (p = 0.0752). Patients aged 0–9 years (61.54%) and 10–18 years (70%), and patients presenting with encephalitis/meningoencephalitis (100%) and ADEM (75%) were more likely to recover fully.

Conclusions: Visual impairment was the dominant symptom in both pediatric and adult patients, while fever was more frequent in pediatric patients. Data suggested that BON and bilateral optic nerve involvement were more common in pediatric cases whereas NMOSD and unilateral optic nerve involvement were more prevalent in adults. The younger patients and patients presenting with encephalitis/meningoencephalitis and ADEM tended to recover better.

E.U. paediatric MOG consortium consensus: Part 1 - Classification of clinical phenotypes of paediatric myelin oligodendrocyte glycoprotein antibody-associated disorders

Over the past few years, increasing interest in the role of autoantibodies against myelin oligodendrocyte glycoprotein (MOG-abs) as a new candidate biomarker in demyelinating central nervous system diseases has arisen. MOG-abs have now consistently been identified in a variety of demyelinating syndromes, with a predominance in paediatric patients. The clinical spectrum of these MOG-ab-associated disorders (MOGAD) is still expanding and differs between paediatric and adult patients. This first part of the Paediatric European Collaborative Consensus emphasises the diversity in clinical phenotypes associated with MOG-abs in paediatric patients and discusses these associated clinical phenotypes in detail. Typical MOGAD presentations consist of demyelinating syndromes, including acute disseminated encephalomyelitis (ADEM) in younger, and optic neuritis (ON) and/or transverse myelitis (TM) in older children. A proportion of patients experience a relapsing disease course, presenting as ADEM followed by one or multiple episode(s) of ON (ADEM-ON), multiphasic disseminated encephalomyelitis (MDEM), relapsing ON (RON) or relapsing neuromyelitis optica spectrum disorders (NMOSD)-like syndromes. More recently, the disease spectrum has been expanded with clinical and radiological phenotypes including encephalitis-like, leukodystrophy-like, and other non-classifiable presentations. This review concludes with recommendations following expert consensus on serologic testing for MOG-abs in paediatric patients, the presence of which has consequences for long-term monitoring, relapse risk, treatments, and for counselling of patient and families. Furthermore, we propose a clinical classification of paediatric MOGAD with clinical definitions and key features. These are operational and need to be tested, however essential for future paediatric MOGAD studies.

E.U. paediatric MOG consortium consensus: Part 4 - Outcome of paediatric myelin oligodendrocyte glycoprotein antibody-associated disorders

There is increasing knowledge on the role of antibodies against myelin oligodendrocyte glycoprotein (MOG-abs) in acquired demyelinating syndromes and autoimmune encephalitis in children. Better understanding and prediction of outcome is essential to guide treatment protocol decisions. Therefore, this part of the Paediatric European Collaborative Consensus provides an oversight of existing knowledge of clinical outcome assessment in paediatric MOG-ab-associated disorders (MOGAD). The large heterogeneity in disease phenotype, disease course, treatment and follow-up protocols is a major obstacle for reliable prediction of outcome. However, the clinical phenotype of MOGAD appears to be the main determinant of outcome. Patients with a transverse myelitis phenotype in particular are at high risk of accruing neurological disability (motor and autonomic), which is frequently severe. In contrast, having a single episode of optic neuritis any time during disease course is broadly associated with a lower risk of persistent disability. Furthermore, MOG-ab-associated optic neuritis often results in good functional visual recovery, although retinal axonal loss may be severe. The field of cognitive and behavioural outcome and epilepsy following demyelinating episodes has not been extensively explored, but in recent studies acute disseminated encephalomyelitis (-like) phenotype in the young children was associated with cognitive problems and epilepsy in long-term follow-up. In conclusion, main domains of importance in determining clinical outcome in paediatric MOGAD are visual, motor, autonomic and cognitive function. A standardised evaluation of these outcome domains in all children is of importance to allow adequate rehabilitation and follow-up.

AQP4-IgG and MOG-IgG Related Optic Neuritis-Prevalence, Optical Coherence Tomography Findings, and Visual Outcomes: A Systematic Review and Meta-Analysis

Background: Optic neuritis (ON) is a cardinal manifestation of multiple sclerosis (MS), aquaporin-4 (AQP4)-IgG-, and myelin oligodendrocyte glycoprotein (MOG)-IgG-associated disease. However, the prevalence of AQP4-IgG seropositivity and MOG-IgG seropositivity in isolated ON is unclear, and studies comparing visual outcomes and optical coherence tomography (OCT)-derived structural retinal measures between MS-ON, AQP4-ON, and MOG-ON eyes are limited by small sample sizes. Objectives: (1) To assess the prevalence of AQP4-IgG and MOG-IgG seropositivity among patients presenting with isolated ON; (2) to compare visual outcomes and OCT measures between AQP4-ON, MOG-ON, and MS-ON eyes. Methods: In this systematic review and meta-analysis, a total of 65 eligible studies were identified by PubMed search. Statistical analyses were performed with random effects models. Results: In adults with isolated ON, AQP4-IgG seroprevalence was 4% in non-Asian and 27% in Asian populations, whereas MOG-IgG seroprevalence was 8 and 20%, respectively. In children, AQP4-IgG seroprevalence was 0.4% in non-Asian and 15% in Asian populations, whereas MOG-IgG seroprevalence was 47 and 31%, respectively. AQP4-ON eyes had lower peri-papillary retinal nerve fiber layer (pRNFL; -11.7 μm, 95% CI: -15.2 to -8.3 μm) and macular ganglion cell + inner plexiform layer (GCIPL; -9.0 μm, 95% CI: -12.5 to -5.4 μm) thicknesses compared with MS-ON eyes. Similarly, pRNFL (-11.2 μm, 95% CI: -21.5 to -0.9 μm) and GCIPL (-6.1 μm, 95% CI: -10.8 to -1.3 μm) thicknesses were lower in MOG-ON compared to MS-ON eyes, but did not differ between AQP4-ON and MOG-ON eyes (pRNFL: -1.9 μm, 95% CI: -9.1 to 5.4 μm; GCIPL: -2.6 μm, 95% CI: -8.9 to 3.8 μm). Visual outcomes were worse in AQP4-ON compared to both MOG-ON (mean logMAR difference: 0.60, 95% CI: 0.39 to 0.81) and MS-ON eyes (mean logMAR difference: 0.68, 95% CI: 0.40 to 0.96) but were similar in MOG-ON and MS-ON eyes (mean logMAR difference: 0.04, 95% CI: -0.05 to 0.14). Conclusions: AQP4-IgG- and MOG-IgG-associated disease are important diagnostic considerations in adults presenting with isolated ON, especially in Asian populations. Furthermore, MOG-IgG seroprevalence is especially high in pediatric isolated ON, in both non-Asian and Asian populations. Despite a similar severity of GCIPL and pRNFL thinning in AQP4-ON and MOG-ON, AQP4-ON is associated with markedly worse visual outcomes.

Understanding Pediatric Neuroimmune Disorder Conflicts: A Neuroradiologic Approach in the Molecular Era

Neuroimmune disorders in children are a complex group of inflammatory conditions of the central nervous system with diverse pathophysiologic mechanisms and clinical manifestations. Improvements in antibody analysis, genetics, neuroradiology, and different clinical phenotyping have expanded knowledge of the different neuroimmune disorders. The authors focus on pediatric-onset myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease, which is a new entity in the spectrum of inflammatory demyelinating diseases, distinct from both multiple sclerosis (MS) and anti-aquaporin-4 (AQP4) antibody neuromyelitis optica spectrum disorders (NMOSDs). The authors review the importance of an optimized antibody-detection assay, the frequency of MOG antibodies in children with acquired demyelinating syndrome (ADS), the disease course, the clinical spectrum, proposed diagnostic criteria, and neuroimaging of MOG antibody-associated disease. Also, they outline differential diagnosis from other neuroimmune disorders in children according to the putative primary immune mechanism. Finally, they recommend a diagnostic algorithm for the first manifestation of ADS or relapsing ADS that leads to four demyelinating syndromes: MOG antibody-associated disease, AQP4 antibody NMOSDs, MS, and seronegative relapsing ADS. This diagnostic approach provides a framework for the strategic role of neuroradiology in diagnosis of ADS and decision making, to optimize patient care and treatment outcome in concert with clinicians. Online supplemental material is available for this article. ^©RSNA, 2020.

Update on Pediatric Optic Neuritis

PURPOSE OF REVIEW

The purpose of this review is to provide an update on advances in the understanding of pediatric demyelinating optic neuritis.

RECENT FINDINGS

In the past decade, the disease phenotypes for demyelinating syndromes in children have been more clearly defined. Pediatric optic neuritis may present as a clinically isolated syndrome or in the setting of underlying neurologic disease. In addition to optic neuritis associated with multiple sclerosis or neuromyelitis optica, recent work has identified antibodies to the myelin oligodendrocyte glycoprotein (MOG IgG) as a unique demyelinating cause with distinct features regarding treatment and prognosis. The disease phenotypes for demyelinating pediatric optic neuritis have expanded. Treatment strategies vary and are not universally effective for each cause of demyelinating disease. Accurately distinguishing among these unique clinical syndromes is therefore critical for initiation of appropriate treatment to prevent disability, to maximize visual outcomes, and to provide insight into long-term prognosis.

Pediatric NMOSD: A Review and Position Statement on Approach to Work-Up and Diagnosis

Neuromyelitis Optica Spectrum Disorder (NMOSD) is an inflammatory demyelinating disease of the central nervous system (CNS) primarily affecting the optic nerves and spinal cord, but also involving other regions of the CNS including the area postrema, periaqueductal gray matter, and hypothalamus. Knowledge related to pediatric manifestations of NMOSD has grown in recent years, particularly in light of newer information regarding the importance of not only antibodies to aquaporin 4 (AQP4-IgG) but also myelin oligodendrocyte glycoprotein (MOG-IgG) in children manifesting clinically with this syndrome. In this review, we describe the current state of the knowledge related to clinical manifestations, diagnosis, and chronic therapies for children with NMOSD, with emphasis on literature that has been published in the last 5 years. Following the review, we propose recommendations for the assessment/follow up clinical care, and treatment of this population.

Pediatric optic neuritis and anti MOG antibodies: a cohort of Italian patients

BACKGROUND

recent studies reported that anti myelin oligodendrocyte glycoprotein (MOG) antibody (ab) related optic neuritis (ON) tend to have characteristics that differ from seronegative ones. The aim of our study was to investigate the clinical characteristics of pediatric anti-MOG ON by comparing anti MOG-ab-seropositive and seronegative patients with ON.

METHODS

in this retrospective Italian multicentre study, participants were identified by chart review of patients evaluated for acquired demyelinating syndromes of the central nervous system (over the period 2009-2019). We selected patients presenting with ON as their first demyelinating event. Inclusion criteria were age < 18 years at symptoms onset; presentation consistent with ON; negativity of anti-aquaporin 4 antibodies (AQP4). Only patients who were tested for MOG-IgG1-ab with a live cell-based assay were included.

RESULTS

22 patients (10 MOG-ab-positive and 12 MOG-ab-negative) were included. Fundus oculi examination at onset showed disc swelling in 9/10 in the MOG-ab-positive cohort and 2/10 in the seronegative group (P = 0.002). Retinal Fiber Nerve Layer (RFNL) thickness measured by Spectral Domain Optical Coherence Tomography (S-OCT) was increased in the 5/5 MOG-ab-positive patients tested and was normal or reduced in the seronegative patients tested (4/4 patients) (P = 0.024). Visual acuity impairment at onset did not differ significantly between the two groups, but the MOG-ab-positive cohort showed better recovery at follow-up both regarding visual acuity (P = 0.025) and expanded disability status scale (EDSS) (P = 0.013). A final diagnosis of MS was frequent among seronegative patients (6/12, 50%), whereas none of the MOG-ab-positive group received a diagnosis of MS (P = 0.015). Clinical relapse frequency was low in both groups: 2/10 MOG-ab-positive and 2/12 seronegative cases relapsed, with a median follow up of 25 months.

CONCLUSION

optic disc swelling and increased RFNL at baseline are strongly associated with MOG-ab positivity. MOG-ab-positive patients with ON showed better recovery compared to the seronegative ones. The relapse rate was low and did not differ among the two groups.

Update on pediatric optic neuritis

PURPOSE OF REVIEW

To summarize recent developments in the classification, investigation and management of pediatric optic neuritis (PON).

RECENT FINDINGS

A recent surge in interest surrounding antibodies to myelin oligodendrocyte glycoprotein antibody (MOG-Ab) has instigated a paradigm shift in our assessment of children with PON. This serological marker is associated with a broad spectrum of demyelinating syndromes that are clinically and radiologically distinct from multiple sclerosis (MS) and aquaporin-4 antibody positive neuromyelitis optica spectrum disorder (AQP4+NMOSD). Optic neuritis is the most common presenting phenotype of MOG-Ab positive-associated disease (MOG+AD). MOG-Ab seropositivity is much more common in the pediatric population and it predicts a better prognosis than MS or AQP4+NMOSD, except in the subset that exhibit a recurrent phenotype.

SUMMARY

A better grasp of MOG+AD features and its natural history has facilitated more accurate risk stratification of children after a presenting episode of PON. Consequently, the initial investigation of PON has broadened to include serology, along with neuroimaging and cerebrospinal fluid analysis. Acute treatment of PON and chronic immunotherapy is also becoming better tailored to the suspected or confirmed diagnoses of MS, AQP4+NMOSD and MOG+AD.