MRI features of demyelinating disease associated with anti-MOG antibodies in adults

MOG Antibody Disease: Nuances in Presentation, Diagnosis, and Management

PURPOSE OF REVIEW

Myelin oligodendrocyte glycoprotein antibody disease (MOGAD) is a distinct neuroinflammatory condition characterized by attacks of optic neuritis, transverse myelitis, and other demyelinating events. Though it can mimic multiple sclerosis and neuromyelitis optica spectrum disorder, distinct clinical and radiologic features which can discriminate these conditions are now recognized. This review highlights recent advances in our understanding of clinical manifestations, diagnosis, and treatment of MOGAD.

RECENT FINDINGS

Studies have identified subtleties of common clinical attacks and identified more rare phenotypes, including cerebral cortical encephalitis, which have broadened our understanding of the clinicoradiologic spectrum of MOGAD and culminated in the recent publication of proposed diagnostic criteria with a familiar construction to those diagnosing other neuroinflammatory conditions. These criteria, in combination with advances in antibody testing, should simultaneously lead to wider recognition and reduced incidence of misdiagnosis. In addition, recent observational studies have raised new questions about when to treat MOGAD chronically, and with which agent. MOGAD pathophysiology informs some of the relatively unique clinical and radiologic features which have come to define this condition, and similarly has implications for diagnosis and management. Further prospective studies and the first clinical trials of therapeutic options will answer several remaining questions about the peculiarities of this condition.

It Looks Like a Spinal Cord Tumor but It Is Not

Differentiating neoplastic from non-neoplastic spinal cord pathologies may be challenging due to overlapping clinical and radiological features. Spinal cord tumors, which comprise only 2-4% of central nervous system tumors, are rarer than non-tumoral myelopathies of inflammatory, vascular, or infectious origins. The risk of neurological deterioration and the high rate of false negatives or misdiagnoses associated with spinal cord biopsies require a cautious approach. Facing a spinal cord lesion, prioritizing more common non-surgical myelopathies in differential diagnoses is essential. A comprehensive radiological diagnostic approach is mandatory to identify spinal cord tumor mimics. The diagnostic process involves a multi-step approach: detecting lesions primarily using MRI techniques, precise localization of lesions, assessing lesion signal intensity characteristics, and searching for potentially associated anomalies at spinal cord and cerebral MRI. This review aims to delineate the radiological diagnostic approach for spinal cord lesions that may mimic tumors and briefly highlight the primary pathologies behind these lesions.

Cervical myelitis: a practical approach to its differential diagnosis on MR imaging

BACKGROUND

 Differential diagnosis of non-compressive cervical myelopathy encompasses a broad spectrum of inflammatory, infectious, vascular, neoplastic, neurodegenerative, and metabolic etiologies. Although the speed of symptom onset and clinical course seem to be specific for certain neurological diseases, lesion pattern on MR imaging is a key player to confirm diagnostic considerations.

METHODS

 The differentiation between acute complete transverse myelitis and acute partial transverse myelitis makes it possible to distinguish between certain entities, with the latter often being the onset of multiple sclerosis. Typical medullary MRI lesion patterns include a) longitudinal extensive transverse myelitis, b) short-range ovoid and peripheral lesions, c) polio-like appearance with involvement of the anterior horns, and d) granulomatous nodular enhancement prototypes.

RESULTS AND CONCLUSION

 Cerebrospinal fluid analysis, blood culture tests, and autoimmune antibody testing are crucial for the correct interpretation of imaging findings. The combination of neuroradiological features and neurological and laboratory findings including cerebrospinal fluid analysis improves diagnostic accuracy.

KEY POINTS

  · The differentiation of medullary lesion patterns, i. e., longitudinal extensive transverse, short ovoid and peripheral, polio-like, and granulomatous nodular, facilitates the diagnosis of myelitis.. · Discrimination of acute complete and acute partial transverse myelitis makes it possible to categorize different entities, with the latter frequently being the overture of multiple sclerosis (MS).. · Neuromyelitis optica spectrum disorders (NMOSD) may start as short transverse myelitis and should not be mistaken for MS.. · The combination of imaging features and neurological and laboratory findings including cerebrospinal fluid analysis improves diagnostic accuracy.. · Additional brain imaging is mandatory in suspected demyelinating, systemic autoimmune, infectious, paraneoplastic, and metabolic diseases..

The Role of MRI in the Diagnosis of Spinal Cord Tumors

Spinal cord tumors are uncommon, and its multiple representatives not always have pathognomonic characteristics, which poses a challenge for both patients and caring physicians. The radiologist performs an important role in recognizing these tumors, as well as in differentiating between neoplastic and non-neoplastic processes, supporting clinical and surgical decision-making in patients with spinal cord injury. Magnetic Resonance Imaging (MRI) assessment, paired with a deep understanding of the various patterns of cord involvement allied to detailed clinical data can provide a diagnosis or significantly limit the differential diagnosis in most cases. In this article, we aim to review the most common and noteworthy intramedullary and extramedullary spinal tumors, as well as some other tumoral mimics, with an emphasis on their MRI morphologic characteristics.

Establishment of a comprehensive diagnostic model for neuromyelitis optica spectrum disorders based on the analysis of laboratory indicators and clinical data

BACKGROUND

To establish a comprehensive diagnostic model for neuromyelitis optica spectrum disorders (NMOSDs) based on laboratory indicators and clinical data.

METHODS

A retrospective method was used to query the medical records of patients with NMOSD from January 2019 to December 2021. At the same time, clinical data of other neurological diseases were also collected for comparison. Clinical data of the NMOSD group and non-NMOSD group were analyzed, and the diagnostic model was established based on these data. In addition, the model was evaluated and verified by the receiver operating curve.

RESULTS

A total of 73 patients with NMOSD were included, and the ratio of males to females was 1:3.06. The indicators that showed differences between the NMOSD group and non NMOSD group included neutrophils (P = 0.0438), PT (P = 0.0028), APTT (P < 0.0001), CK (P = 0.002), IBIL (P = 0.0181), DBIL (P < 0.0001), TG (P = 0.0078), TC (P = 0.0117), LDL-C (P = 0.0054), ApoA1 (P = 0.0123), ApoB (P = 0.0217), TPO antibody (P = 0.012), T3 (P = 0.0446), B lymphocyte subsets (P = 0.0437), urine sg (P = 0.0123), urine pH (P = 0.0462), anti-SS-A antibody (P = 0.0036), RO-52 (P = 0.0138), CSF simplex virus antibody I-IGG (P = 0.0103), anti-AQP4 antibody (P < 0.0001), and anti-MOG antibody (P = 0.0036). Logistic regression analysis showed that changes in ocular symptoms, anti-SSA antibody, anti-TPO antibody, B lymphocyte subsets, anti-AQP4 antibody, anti-MOG antibody, TG, LDL, ApoB, and APTT had a significant impact on diagnosis. The AUC of the combined analysis was 0.959. The AUC of the new ROC for AQP4- and MOG- antibody negative NMOSD was 0.862.

CONCLUSIONS

A diagnostic model was successfully established, which can play an important role in differential diagnosis of NMOSD.

The Role of MRI in Differentiating Demyelinating and Inflammatory (not Infectious) Myelopathies

Demyelinating and inflammatory myelopathies represent a group of diseases with characteristic patterns in neuroimaging and several differential diagnoses. The main imaging patterns of demyelinating myelopathies (multiple sclerosis, neuromyelitis optica spectrum disorder, acute disseminated encephalomyelitis, and myelin oligodendrocyte glycoprotein antibody-related disorder) and inflammatory myelopathies (systemic lupus erythematosus-myelitis, sarcoidosis-myelitis, Sjögren-myelitis, and Behçet's-myelitis) will be discussed in this article, highlighting key points to the differential diagnosis.

MRI to differentiate multiple sclerosis, neuromyelitis optica, and myelin oligodendrocyte glycoprotein antibody disease

Differentiating multiple sclerosis (MS) from other relapsing inflammatory autoimmune diseases of the central nervous system such as neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is crucial in clinical practice. The differential diagnosis may be challenging but making the correct ultimate diagnosis is critical, since prognosis and treatments differ, and inappropriate therapy may promote disability. In the last two decades, significant advances have been made in MS, NMOSD, and MOGAD including new diagnostic criteria with better characterization of typical clinical symptoms and suggestive imaging (magnetic resonance imaging [MRI]) lesions. MRI is invaluable in making the ultimate diagnosis. An increasing amount of new evidence with respect to the specificity of observed lesions as well as the associated dynamic changes in the acute and follow-up phase in each condition has been reported in distinct studies recently published. Additionally, differences in brain (including the optic nerve) and spinal cord lesion patterns between MS, aquaporin4-antibody-positive NMOSD, and MOGAD have been described. We therefore present a narrative review on the most relevant findings in brain, spinal cord, and optic nerve lesions on conventional MRI for distinguishing adult patients with MS from NMOSD and MOGAD in clinical practice. In this context, cortical and central vein sign lesions, brain and spinal cord lesions characteristic of MS, NMOSD, and MOGAD, optic nerve involvement, role of MRI at follow-up, and new proposed diagnostic criteria to differentiate MS from NMOSD and MOGAD were discussed.

Marked central canal T2-hyperintensity in MOGAD myelitis and comparison to NMOSD and MS

OBJECTIVE

To assess marked central canal T2-hyperintensity in patients with myelin-oligodendrocyte glycoprotein antibody-associated disease (MOGAD) myelitis compared to myelitis patients with aquaporin-4-antibody-positive neuromyelitis optica spectrum disorder (AQP4 + NMOSD) and multiple sclerosis (MS).

MATERIAL/METHODS

Two blinded raters evaluated spinal cord magnetic resonance imaging (MRIs) of myelitis patients with MOGAD (n = 63), AQP4 + NMOSD (n = 37), and MS (n = 26), assessing for marked central canal T2-hyperintensity and its evolution. If there were conflicting results, a third neurologist assessed the MRI.

RESULTS

Marked central canal T2-hyperintensity was more frequent in patients with MOGAD (18/63[29%]) than MS (1/26[4%]; p = 0.01) myelitis but did not differ from AQP4 + NMOSD (13/37[35%]; p = 0.49). Marked central canal T2-hyperintensity had completely resolved on follow-up axial MRI for most MOGAD (12/14[86%]) and AQP4 + NMOSD (10/10[100%]; p = 0.49) patients.

CONCLUSIONS

Marked central canal T2-hyperintensity is a common transient radiologic accompaniment of MOGAD and AQP4 + NMOSD myelitis, but not MS myelitis.

Utility of optical coherence tomography in patients of central immune mediated demyelinating diseases - A prospective study

Optical coherence tomography (OCT) is a non-invasive tool to measure thickness of various layers of retina. Recently, retinal nerve fibre layer (RNFL) and ganglion cell and inner plexiform layer (GCIP) thinning has been observed in OCT in patients with multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD), This study compared OCT profile, along with visual acuity (VA), color vision (CV), contrast saturation (CS) and visual evoked potentials (VEP) in two main cohorts of MS and NMOSD and with controls, during acute episode of optic neuritis (ON), at 3 and 6 months. We found that changes of ON were present in 75% of MS eyes and in 45% of NMOSD patients. Of these, subclinical involvement was present in 56.25% of MS eyes and only in 5% of NMOSD eyes suggesting frequent subclinical involvement in the former. Mean RNFL was 95.23 ± 15.53 in MS and 66.14 ± 43.73 in NMOSD after 6 months of ON episode. Thinning of NQ and IQ was observed in NMOSD eyes in the immediate period after ON attack. At 6 months relative sparing of RNFL in TQ was observed in NMOSD ON eyes and MS ON showed predilection for involvement of TQ.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Myelin Oligodendrocyte Glycoprotein as an Autoantigen in Inflammatory Demyelinating Diseases of the Central Nervous System

Demyelinating diseases of the central nervous system are caused by an autoimmune attack on the myelin sheath surrounding axons. Myelin structural proteins become antigenic, leading to the development of myelin lesions. The use of highly specialized laboratory diagnostic techniques for identification of specific antibodies directed against myelin components can significantly improve diagnostic approaches. Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) currently includes demyelinating syndromes with known antigens. Based on the demonstrated pathogenic role of human IgG against MOG, MOGAD was classified as a distinct nosological entity. However, generation of multiple MOG isoforms by alternative splicing hinders antigen detection even with the most advanced immunofluorescence techniques. On the other hand, MOG conformational changes ensure the structural integrity of other myelin proteins and maintain human-specific mechanisms of immune autotolerance.

The Acute Optic Neuritis Network (ACON): Study protocol of a non-interventional prospective multicenter study on diagnosis and treatment of acute optic neuritis

Optic neuritis (ON) often occurs at the presentation of multiple sclerosis (MS), neuromyelitis optica spectrum disorders (NMOSD), and myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD). The recommended treatment of high-dose corticosteroids for ON is based on a North American study population, which did not address treatment timing or antibody serostatus. The Acute Optic Neuritis Network (ACON) presents a global, prospective, observational study protocol primarily designed to investigate the effect of time to high-dose corticosteroid treatment on 6-month visual outcomes in ON. Patients presenting within 30 days of the inaugural ON will be enrolled. For the primary analysis, patients will subsequently be assigned into the MS-ON group, the aquapotin-4-IgG positive ON (AQP4-IgG+ON) group or the MOG-IgG positive ON (MOG-IgG+ON) group and then further sub-stratified according to the number of days from the onset of visual loss to high-dose corticosteroids (days-to-Rx). The primary outcome measure will be high-contrast best-corrected visual acuity (HC-BCVA) at 6 months. In addition, multimodal data will be collected in subjects with any ON (CIS-ON, MS-ON, AQP4-IgG+ON or MOG-IgG+ON, and seronegative non-MS-ON), excluding infectious and granulomatous ON. Secondary outcomes include low-contrast best-corrected visual acuity (LC-BCVA), optical coherence tomography (OCT), magnetic resonance imaging (MRI) measurements, serum and cerebrospinal fluid (CSF) biomarkers (AQP4-IgG and MOG-IgG levels, neurofilament, and glial fibrillary protein), and patient reported outcome measures (headache, visual function in daily routine, depression, and quality of life questionnaires) at presentation at 6-month and 12-month follow-up visits. Data will be collected from 28 academic hospitals from Africa, Asia, the Middle East, Europe, North America, South America, and Australia. Planned recruitment consists of 100 MS-ON, 50 AQP4-IgG+ON, and 50 MOG-IgG+ON. This prospective, multimodal data collection will assess the potential value of early high-dose corticosteroid treatment, investigate the interrelations between functional impairments and structural changes, and evaluate the diagnostic yield of laboratory biomarkers. This analysis has the ability to substantially improve treatment strategies and the accuracy of diagnostic stratification in acute demyelinating ON.

Trial registration

ClinicalTrials.gov, identifier: NCT05605951.

Stroke-like presentation of autoimmune chorea with positive anti-Yo and anti-MOG antibodies: a case report

With the in-depth study of autoimmune encephalitis, more and more antibody combinations and clinical manifestations appear in our sights, enriching the spectrum of autoimmune encephalitis. Here, we report a case of a 58-year-old male patient with sudden involuntary movement of the left limb. The brain MRI was normal. CSF analysis showed slightly elevated protein (548.38 mg/L) and normal cell count(1.00 10^⁶/L). No tumors were detected by the whole-body PET-CT. Positive anti-Yo and anti-MOG antibodies were found in the blood. So we considered the diagnosis of autoimmune chorea with positive anti-Yo and anti-MOG antibodies, after immunoglobulin shock and methylprednisolone shock therapy were used, the patient's involuntary movement gradually disappeared. This is the first case of autoimmune encephalitis with both anti-Yo and anti-MOG antibodies, and stroke-like chorea is also rare. This case enriches the clinical presentation of double antibody-associated encephalitis.

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease: Presentation and outcomes of adults at a single center

BACKGROUND/INTRODUCTION

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a chronic demyelinating disorder that has been increasingly recognized since the serum antibody became commercially available in 2017. The most common clinical presentation is optic neuritis, and first line acute treatment is intravenous (IV) steroids. However, there are many questions that remain unanswered. For clinicians and patients, the primary question is whether relapses will occur and whether to treat with chronic therapy.

METHODS

This retrospective chart review examined characteristics of thirty-three known adult MOGAD cases at a single institute. Data was collected on patient demographics, clinical presentation, objective diagnosis with MRI and serum antibody levels, acute and chronic treatment and disease outcomes.

RESULTS

Our MOGAD cases revealed a slight female to male predominance of 1.5:1. No racial groups were affected disproportionately, and age of symptom onset spanned a large range with a median of 40 years. The most common clinical and radiologic presentation was optic neuritis followed by transverse myelitis and brainstem symptoms/lesions. IV methylprednisolone was used in the vast majority of cases for acute treatment. 83.3% of our patients were treated with chronic therapy at some point during their disease course. Therapies include rituximab, IVIG, ocrelizumab, mycophenolate mofetil and ofatumumab. The majority of our patients were treated with rituximab and we did not see a significant benefit of yearly relapse reduction for rituximab versus other therapies. Our cohort had a higher-than- expected percentage of cases with relapsing disease (56.3%) compared to monophasic (43.8%).

DISCUSSION/CONCLUSION

Our study confirms prior data regarding the demographics, clinical presentation and radiologic presentation of MOGAD. There is no consensus on whether maintenance therapy should be started for MOGAD cases with a single clinical event. Our cohort showed a higher relapse rate than has been reported previously and all known relapses occurred within one year of diagnosis. More data is necessary to confirm risk of relapse in the years following diagnosis. In addition, further data on biomarkers are needed to predict the disease course could help guide management.

Myelin oligodendrocyte glycoprotein antibody-associated disease in children: Are there MRI predictors of relapse?

BACKGROUND AND PURPOSE

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is increasingly recognized in children. Some children have isolated disease while others relapse. The study evaluates clinical, demographic and imaging features children with positive anti-MOG antibodies comparing to previously reported findings and correlate patterns on MR imaging with a relapsing course in MOGAD.

MATERIAL AND METHODS

All pediatrics patients with serum anti-MOG antibodies were reviewed. Demographic, clinical, and imaging data were evaluated. Patients with a relapsing course were compared to those with a single event. We assessed initial MR images of the brain, orbits and spine obtained at the onset of clinical symptoms, whether performed at our institution or elsewhere.

RESULTS

Thirty patients were included, fourteen with a single event and sixteen with more than one clinical event. The mean age was 8.1 years, with a mean follow-up of 58 months (range of 0.67 to 238 months). The relapsing patients had a mean of 3.5 relapses (range 2-12). 55% of patients had long segment optic nerve lesions, 53% of patients had cortical or peripheral white matter lesions, and 46% of patients had thalamic lesions. 43% of patients had spinal cord lesions, with 39% involving the central cord and 26% with long segment involvement. The imaging features between the groups were not statistically significant.

CONCLUSION

There were no distinguishing features in relapsing versus non-relapsing patients. In the absence of any predictive characteristics for future relapse, patients should have regular clinical and imaging follow up.

Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease Presenting as Intracranial Hypertension: A Case Report

The production of autoantibodies against myelin oligodendrocyte glycoprotein (MOG) can cause a spectrum of autoimmune disorders, including optic neuritis, transverse myelitis, brainstem encephalitis, and acute disseminated encephalomyelitis. In this study, we present the case of a 19-year-old woman with an unusual clinical presentation of intracranial hypertension (IH) and bilateral papilledema. The patient presented with symptoms of increased intracranial pressure, which followed a relapsing, remitting course over several months. Serial CSF studies showed an increased opening pressure during clinical relapses. The CSF and serum tested positive for MOG immunoglobulin G antibodies. Contrast-enhanced MRI of the brain showed mild meningeal enhancement in the left parietal region with subtle underlying cortical hyperintensities, indicating possible fluid-attenuated inversion recovery variable unilateral enhancement of the leptomeninges. The patient responded well to immunosuppressive therapy using rituximab. The presentation of MOG antibody-associated disease (MOGAD) as IH without optic neuritis is rare. This report presents the first description of a relapsing remitting course presenting each time with only symptoms of raised intracranial pressure, without developing any typical clinical manifestations of MOGAD.

Neuroimaging features in inflammatory myelopathies: A review

Spinal cord involvement can be observed in the course of immune-mediated disorders. Although multiple sclerosis (MS) represents the leading cause of inflammatory myelopathy, an increasing number of alternative etiologies must be now considered in the diagnostic work-up of patients presenting with myelitis. These include antibody-mediated disorders and cytotoxic T cell-mediated diseases targeting central nervous system (CNS) antigens, and systemic autoimmune conditions with secondary CNS involvement. Even though clinical features are helpful to orient the diagnostic suspicion (e.g., timing and severity of myelopathy symptoms), the differential diagnosis of inflammatory myelopathies is often challenging due to overlapping features. Moreover, noninflammatory etiologies can sometimes mimic an inflammatory process. In this setting, magnetic resonance imaging (MRI) is becoming a fundamental tool for the characterization of spinal cord damage, revealing a pictorial scenario which is wider than the clinical manifestations. The characterization of spinal cord lesions in terms of longitudinal extension, location on axial plane, involvement of the white matter and/or gray matter, and specific patterns of contrast enhancement, often allows a proper differentiation of these diseases. For instance, besides classical features, such as the presence of longitudinally extensive spinal cord lesions in patients with aquaporin-4-IgG positive neuromyelitis optica spectrum disorder (AQP4+NMOSD), novel radiological signs (e.g., H sign, trident sign) have been recently proposed and successfully applied for the differential diagnosis of inflammatory myelopathies. In this review article, we will discuss the radiological features of spinal cord involvement in autoimmune disorders such as MS, AQP4+NMOSD, myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), and other recently characterized immune-mediated diseases. The identification of imaging pitfalls and mimics that can lead to misdiagnosis will also be examined. Since spinal cord damage is a major cause of irreversible clinical disability, the recognition of these radiological aspects will help clinicians achieve a correct and prompt diagnosis, treat early with disease-specific treatment and improve patient outcomes.

Diagnosis and classification of optic neuritis

There is no consensus regarding the classification of optic neuritis, and precise diagnostic criteria are not available. This reality means that the diagnosis of disorders that have optic neuritis as the first manifestation can be challenging. Accurate diagnosis of optic neuritis at presentation can facilitate the timely treatment of individuals with multiple sclerosis, neuromyelitis optica spectrum disorder, or myelin oligodendrocyte glycoprotein antibody-associated disease. Epidemiological data show that, cumulatively, optic neuritis is most frequently caused by many conditions other than multiple sclerosis. Worldwide, the cause and management of optic neuritis varies with geographical location, treatment availability, and ethnic background. We have developed diagnostic criteria for optic neuritis and a classification of optic neuritis subgroups. Our diagnostic criteria are based on clinical features that permit a diagnosis of possible optic neuritis; further paraclinical tests, utilising brain, orbital, and retinal imaging, together with antibody and other protein biomarker data, can lead to a diagnosis of definite optic neuritis. Paraclinical tests can also be applied retrospectively on stored samples and historical brain or retinal scans, which will be useful for future validation studies. Our criteria have the potential to reduce the risk of misdiagnosis, provide information on optic neuritis disease course that can guide future treatment trial design, and enable physicians to judge the likelihood of a need for long-term pharmacological management, which might differ according to optic neuritis subgroups.

Coexistence of Myelin Oligodendrocyte Glycoprotein Immunoglobulin G and Neuronal or Glial Antibodies in the Central Nervous System: A Systematic Review

Background: Myelin oligodendrocyte glycoprotein immunoglobulin G (MOG-IgG) has been considered a diagnostic marker for patients with demyelinating disease, termed “MOG-IgG associated disorder” (MOGAD). Recently, the coexistence of MOG-IgG and other neuronal or glial antibodies has attracted extensive attention from clinicians. In this article, we systematically review the characteristics of MOG-IgG-related antibody coexistence syndrome. Methods: Two authors independently searched PubMed for relevant studies published before October 2021. We also manually searched the references of each related article. The appropriateness of the included studies was assessed by reading the titles, abstracts, and full texts if necessary. Results: Thirty-five relevant publications that met our inclusion criteria were finally included, of which fourteen were retrospective studies and twenty-one were case reports. A total of 113 patients were reported to show the coexistence of MOG-IgG and neuronal or glial antibodies. Additionally, 68.14% of patients were double positive for MOG-IgG and N-Methyl-D-Aspartate Receptor-IgG (NMDAR-IgG), followed by 23.01% of patients who were double positive for MOG-IgG and aquaporin4-IgG (AQP4-IgG). Encephalitis was the predominant phenotype when MOG-IgG coexisted with NMDAR-IgG, probably accompanied by imaging features of demyelination. Patients with dual positivity for MOG-IgG and AQP4-IgG experienced more severe disease and more frequent relapses. The coexistence of MOG-IgG and antibodies other than NMDAR-IgG and AQP4-IgG was extremely rare, and the clinical presentations were diverse and atypical. Except for patients who were double positive for MOG-IgG and AQP4-IgG, most patients with multiple antibodies had a good prognosis. Conclusions: MOG-IgG may coexist with neuronal or glial antibodies. Expanded screening for neuronal or glial antibodies should be performed in patients with atypical clinical and radiological features.

Positive Predictive Value of MOG-IgG for Clinically Defined MOG-AD Within a Real-World Cohort

Myelin oligodendrocyte glycoprotein antibody associated disease (MOG-AD) is a CNS demyelinating disease, typically presenting with optic neuritis, transverse myelitis, and/or ADEM-like syndromes. The positive predictive value (PPV) of MOG-IgG testing by live cell-based assay was reported to be 72% in a study performed at the Mayo Clinic using a cut-off of 1:20. PPV may vary depending upon the tested population, thus supporting further investigation of MOG-IgG testing at other centers. In this real-world institutional cohort study, we determined the PPV of serum MOG-IgG for clinically defined MOG-AD in our patient population. The Massachusetts General Brigham Research Patient Data Registry database was queried for patients with positive serum MOG-IgG detection, at least once, between January 1, 2017 and March 25, 2021. All were tested via the MOG-IgG1 fluorescence-activated cell sorting assay (Mayo Laboratories, Rochester, MN). MOG-IgG positive cases were reviewed for fulfillment of typical MOG-AD clinical features, determined by treating neurologists and study authors. Of 1,877 patients tested, 78 (4.2%) patients tested positive for MOG-IgG with titer ≥1:20, and of these, 67 had validated MOG-AD yielding a PPV of 85.9%. Using a ≥1:40 titer cutoff, 65 (3.5%) tested positive and PPV was 93.8%. Three MOG positive cases had a prototypical multiple sclerosis diagnosis (RRMS n = 2, titers 1:20 and 1:40; PPMS n = 1; 1:100). The treating diagnosis for one RRMS patient with a 1:40 titer was subsequently modified to MOG-AD by treating neurologists. Validated diagnoses of the remaining positive patients without MOG-AD included: migraine (n = 2, titers 1:20, 1:100), inclusion body myositis (n = 1, titer 1:100), autoimmune encephalitis (n = 2, titers 1:20, 1:20), hypoxic ischemic brain injury (n = 1, titer 1:20), IgG4-related disease (n = 1, titer 1:20), and idiopathic hypertrophic pachymeningitis (n = 1, titer 1:20). In our cohort, the PPV for MOG-IgG improved utilizing a titer cut-off of ≥1:40. The presence of positive cases with and without demyelinating features, emphasizes a need for testing in the appropriate clinical context, analysis of titer value and clinical interpretation.

Differences in Neuropathic Pain and Radiological Features Between AQP4-ON, MOG-ON, and IDON

Purpose

The purpose of this study was to investigate pain and radiological features of different types of first-episode demyelinating optic neuritis (ON).

Methods

Eighty-three patients presenting with first-episode aquaporin-4 (AQP4) antibody-associated ON (AQP4-ON; n = 28), myelin oligodendrocyte glycoprotein (MOG) antibody-associated ON (MOG-ON; n = 26) and idiopathic demyelinating optic neuritis (IDON, n = 29) were included in this retrospective case-control study. We assessed optic nerve lesions on magnetic resonance imaging (MRI), acute pain associated with onset of optic neuritis and clinical characteristics of those ON patients with different serum autoantibody status.

Results

24 AQP4-ON patients (85.75%), 23 MOG-ON patients (88.5%) and 24 IDON patients (82.8%) suffered from ON-associated pain. MOG-ON had mostly retro-orbital pain; AQP4-ON and IDON had mostly neuropathic pain. In addition, pain was more severe in AQP4ON patients than in other ON patients. In MRI, bilateral involvement was more common in AQP4-ON than IDON (26.9 and 3.7%); radiological optic nerve head swelling was more common in MOG-ON than in AQP4-ON and IDON (68.0 vs. 23.1 vs. 25.9%). MRI lesion in peri-optic nerve sheath was more common in AQP4-ON (53.8 vs. 16.0 vs. 3.7%). In 70 patients with ON-associated pain, gadolinium enhancement of orbital optic nerve was most common in MOG-ON patients (82.4 vs. 55.0 vs. 33.3%, P = 0.018), and enhancement of optic chiasma was most common in AQP4-ON patients (40.0 vs. 5.9 vs. 6.7%, P = 0.015). Perineural and orbital enhancement was observed only in patients with MOG-ON (P < 0.001). The length of enhancement was longer in AQP4-ON patients than in MOG-ON and IDON patients.

Conclusion

Pain is a common symptom in patients with all types of demyelinating ON. AQP4-ON is frequently associated with severe ON-associated pain and longitudinally extensive optic nerve inflammatory lesions. Intra-orbital and peri-optic inflammation were more frequently observed in patients with MOG-ON, which was closely related to optic disc swelling and retro-orbital pain provoked by eye movements.

Spinal Dural Arteriovenous Fistula: A Mimic of Demyelinating Disease and Radiculopathy

Spinal dural arteriovenous fistula (SDAVF) is characterized by an abnormal connection between a radicular artery and the venous plexus producing spinal cord venous congestion. It manifests with nonspecific sensory and motor symptoms. We present three cases of SDAVF with different forms of presentation; in two cases, an autoimmune etiology was considered, and in the third case, the initial diagnosis was chronic radiculopathy. In all three cases, a serpentine enhancement was observed after the gadolinium in the dorsal region of the spinal cord corresponded to flow voids in T2-weighted images, which guided the diagnosis. SDAVF should be considered in atypical clinical presentations of radiculopathies or spinal cord syndromes, especially spinal conus or epicone syndrome. Likewise, it should be part of the differential diagnosis of spinal cord presentations of demyelinating diseases such as multiple sclerosis or neuromyelitis optica spectrum disorders.

Clinical Features and Imaging Findings of Myelin Oligodendrocyte Glycoprotein-IgG-Associated Disorder (MOGAD)

Myelin oligodendrocyte glycoprotein-IgG-associated disorder (MOGAD) is a nervous system (NS) demyelination disease and a newly recognized distinct disease complicated with various diseases or symptoms; however, MOGAD was once considered a subset of neuromyelitis optica spectrum disorder (NMOSD). The detection of MOG-IgG has been greatly improved by the cell-based assay test method. In one study, 31% of NMOSD patients with negative aquaporin-4 (AQP-4) antibody were MOG-IgG positive. MOGAD occurs in approximately the fourth decade of a person’s life without a markedly female predominance. Usually, optic neuritis (ON), myelitis or acute disseminated encephalomyelitis (ADEM) encephalitis are the typical symptoms of MOGAD. MOG-IgG have been found in patients with peripheral neuropathy, teratoma, COVID-19 pneumonia, etc. Some studies have revealed the presence of brainstem lesions, encephalopathy or cortical encephalitis. Attention should be given to screening patients with atypical symptoms. Compared to NMOSD, MOGAD generally responds well to immunotherapy and has a good functional prognosis. Approximately 44-83% of patients undergo relapsing episodes within 8 months, which mostly involve the optic nerve, and persistently observed MOG-IgG and severe clinical performance may indicate a polyphasic course of illness. Currently, there is a lack of clinical randomized controlled trials on the treatment and prognosis of MOGAD. The purpose of this review is to discuss the clinical manifestations, imaging features, outcomes and prognosis of MOGAD.

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

Objective

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

Methods

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

Results

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

Conclusion

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

Magnetic resonance imaging evaluation of spinal cord lesions: what can we find? - Part 2. Inflammatory and infectious injuries

Diseases involving the spinal cord include a heterogeneous group of abnormalities, including those of inflammatory, infectious, neoplastic, vascular, metabolic, and traumatic origin. Making the clinical differentiation between different entities is often difficult, magnetic resonance imaging being the diagnostic method of choice. Although the neuroimaging findings are not pathognomonic, many are quite suggestive, and the radiologist can assist in the diagnosis and, consequently, in the therapeutic guidance. In this second part of our article, the objective is to review the magnetic resonance imaging findings of the main inflammatory and infectious spinal cord injuries.

Clinical and neuroimaging findings in MOGAD-MRI and OCT

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

Evidence for and against subclinical disease activity and progressive disease in MOG antibody disease and neuromyelitis optica spectrum disorder

Myelin oligodendrocyte glycoprotein antibody disease (MOGAD) and aquaporin-4 IgG seropositive neuromyelitis optica spectrum disorder (AQP4-IgG+ NMOSD) are generally considered to be relapsing disorders, without clinical progression or subclinical disease activity outside of clinical relapses, in contrast to multiple sclerosis (MS). With advances in the diagnosis and treatment of these conditions, prolonged periods of remission without relapses can be achieved, and the question of whether progressive disease courses can occur has re-emerged. In this review, we focus on studies exploring evidence for and against relapse-independent clinical progression and/or subclinical disease activity in patients with MOGAD and AQP4-IgG+ NMOSD.

Retinal optical coherence tomography and magnetic resonance imaging in neuromyelitis optica spectrum disorders and MOG-antibody associated disorders: an updated review

INTRODUCTION

Neuromyelitis optica spectrum disorders (NMOSD) and myelin oligodendrocyte glycoprotein IgG antibody-associated disorders (MOGAD) comprise two groups of rare neuroinflammatory diseases that cause attack-related damage to the central nervous system (CNS). Clinical attacks are often characterized by optic neuritis, transverse myelitis, and to a lesser extent, brainstem encephalitis/area postrema syndrome. Retinal optical coherence tomography (OCT) is a non-invasive technique that allows for in vivo thickness quantification of the retinal layers. Apart from OCT, magnetic resonance imaging (MRI) plays an increasingly important role in NMOSD and MOGAD diagnosis based on the current international diagnostic criteria. Retinal OCT and brain/spinal cord/optic nerve MRI can help to distinguish NMOSD and MOGAD from other neuroinflammatory diseases, particularly from multiple sclerosis, and to monitor disease-associated CNS-damage.

AREAS COVERED

This article summarizes the current status of imaging research in NMOSD and MOGAD, and reviews the clinical relevance of OCT, MRI and other relevant imaging techniques for differential diagnosis, screening and monitoring of the disease course.

EXPERT OPINION

Retinal OCT and MRI can visualize and quantify CNS damage in vivo, improving our understanding of NMOSD and MOGAD pathology. Further efforts on the standardization of these imaging techniques are essential for implementation into clinical practice and as outcome parameters in clinical trials.

Case Report: Post-Chikungunya-Associated Myeloneuropathy

Chikungunya virus (CHIKV) is an arbovirus endemic to South Asia with frequent outbreaks. A wide spectrum of neurological complications has been described in Chikungunya infections. Myeloneuropathy is a rare complication seen in Chikungunya and is proposed to have an underlying immune mediated pathogenesis. We report a case of a 45-year-old man presenting to the emergency services with acute onset of quadriparesis, breathlessness, urinary retention, profound pain, and sensory disturbances 6 weeks after the onset of high-grade fever and arthralgia. On examination, the patient had Medical Research Council grade 1 flaccid quadriparesis with prominent wasting and areflexia with distinct sensory level at T4. Immunoglobulin M CHIKV antibodies were positive, tested twice at a 1-week interval. He had notable magnetic resonance imaging (MRI) findings in the form of patchy T2 hyperintensities involving the entire length of the cervical and thoracic cord with normal brain imaging and extensive short tau inversion recovery hyperintense signal changes on muscle MRI. He was treated with five cycles of plasmapheresis and intravenous methylprednisolone followed by oral steroids for 8 weeks. At 20-week follow-up, the patient had improvement in upper limb weakness, but paraparesis persisted. The case highlights the presence of unusual MRI findings and also the importance of early recognition of after infective neurological complications, and prompt treatment with immunomodulation may be beneficial.

Distinct patterns of MRI lesions in MOG antibody disease and AQP4 NMOSD: a systematic review and meta-analysis

BACKGROUND

the distinct MRI features of MOG-antibody disease (MOG-AD) and AQP4-NMOSD are still poorly defined. We performed a systematic review and meta-analysis to identify specific patterns of MRI abnormalities able to discriminate between MOG-AD and AQP4-NMOSD.

METHODS

fourteen case-series (1028 patients) were included. Outcomes were MRI lesion patterns in optic nerve (ON), brain and spinal cord (SC) that were selected after a systematic literature review and analysed separately as the event rate for individual MRI lesions in MOG-AD (experimental group) and AQP4-NMOSD (control group) by using a random effect model.

RESULTS

MOG-AD showed a higher number of MRI lesions than AQP4-NMOSD patients in the retrobulbar ON (OR=5.67; 95%CI=2.11-15.24; p=0.0006) with ON head swelling (OR=8.20; 95%CI=4.13-16.28; p<0.00001), corpus callosum (OR=2.30; 95%CI=1.11-4.76; p=0.02), pons (OR=2.87; 95%CI=1.45-5.67; p=0.002), and lumbar/conus SC (OR=3.47; 95%CI=1.66-7.24; p=0.0009). Conversely, lesions in the canalicular (OR=0.42; 95%CI=0.18-0.98; p=0.05) and intracranial ON (OR=0.30; 95%CI=0.11=0.84; p=0.02), area postrema (OR=0.12; 95%CI=0.02-0.61; p=0.01), medulla (OR=0.40; 95%CI=0.20-0.78; p=0.007), and cervical SC (OR=0.29; 95%CI=0.09-0.92; p=0.04) were prominent in patients with AQP4-NMOSD. Participants' age was found to be a source of heterogeneity across studies.

CONCLUSION

our study provides further evidence that MOG-AD and AQP4-NMOSD have distinct MRI features that may help clinicians for an early differential diagnosis.

State-of-the-Art Review: Demyelinating Diseases in Indonesia

Demyelinating diseases are more common in Indonesia than previously believed. However, it is still a challenge for a country such as Indonesia to implement the scientific medical advances, especially in the diagnostic process of demyelinating diseases, to achieve the best possible outcome for these groups of patients, within the constraints of what is socially, technologically, economically, and logistically achievable. In this review, we address the 4 major classes of demyelinating disease: multiple sclerosis (MS), neuromyelitis optica (NMO), anti-MOG-associated encephalomyelitis (MOG-EM), and acute disseminated encephalomyelitis (ADEM), and discuss their prevalence, demographics, clinical diagnosis workup, and imaging features in the Indonesian population, as well as the challenges we face in their diagnosis and therapeutic approach. We hope that this overview will lead to a better awareness of the spectrum of demyelinating diseases of the central nervous system in Indonesia.

Bilateral Meningo-Cortical Involvement in Anti-myelin Oligodendrocyte Glycoprotein-IgG Associated Disorders: A Case Report

Cortical T2-weighted fluid-attenuated inversion recovery (FLAIR)-hyperintense lesions in anti-myelin oligodendrocyte glycoprotein (MOG)-associated encephalitis with seizures (FLAMES) are mostly unilateral and rarely spread to the bilateral cortex and meninges. We describe a case of MOG-immunoglobulin G (IgG) associated disorder (MOGAD) in a 39-year-old male with bilateral meningo-cortical involvement. The patient was hospitalized for epilepsy, fever, and headache. The initial MRI revealed abnormalities in the sulci of the bilateral frontal, temporal, and parietal lobes. He was considered to have infectious encephalitis and given empiric antibiotic and antiviral therapy, which were ineffective. His condition rapidly improved after the patient was switched to high-dose immunoglobulin therapy. No tests supported the presence of central nervous system (CNS) infections or autoimmune encephalitis. The second and third MRI scans showed reduced but still clearly observable meningo-cortical lesions. The patient was discharged without a definite diagnosis, but reported severe left vision impairment 25 days later. A fourth MRI showed signs typical of demyelinating CNS disease in addition to the original meningo-cortical lesions. The patient's symptoms were initially relieved by low-dose corticosteroid therapy, but they eventually returned, and he was re-admitted. The original lesions were diminished on the fifth MRI scan, but new lesions had developed in the deep white matter. A positive cell-based assay for MOG-IgG in serum confirmed MOGAD. The patient received high-dose corticosteroid treatment followed by an oral methylprednisolone taper, and his visual acuity gradually improved. The sixth and final MRI showed substantial decreases in the original lesions without new lesion formation. This unique case presents the complete diagnosis and treatment process for MOGAD with bilateral meningo-cortical involvement and may provide a reference for prompt diagnosis.

A window into the future? MRI for evaluation of neuromyelitis optica spectrum disorder throughout the disease course

Neuromyelitis optica spectrum disorder (NMOSD) is a relapsing, inflammatory disease of the central nervous system marked by relapses often associated with poor recovery and long-term disability. Magnetic resonance imaging (MRI) is recognized as an important tool for timely diagnosis of NMOSD as, in combination with serologic testing, it aids in distinguishing NMOSD from possible mimics. Although the role of MRI for disease monitoring after diagnosis is not as well established, MRI may provide important prognostic information and help differentiate between relapses and pseudorelapses. Increasing evidence of subclinical disease activity and the emergence of newly approved, highly effective immunotherapies for NMOSD adjure us to re-evaluate MRI as a tool to guide optimal treatment selection and escalation throughout the disease course. In this article we review the role of MRI in NMOSD diagnosis, prognostication, disease monitoring, and treatment selection.

[Differential diagnostics of autoimmune inflammatory spinal cord diseases]

Myelitis is an acute or subacute inflammatory syndrome of the spinal cord. Myelopathy, often used as a synonym and presenting with similar symptoms in clinical practice, can be caused by numerous, not primarily inflammatory etiologies and might also show a progressive disease course. Within the last decade the spectrum of autoimmune myelitis was significantly broadened as was the spectrum of diagnostic methods. Apart from the characteristic example of multiple sclerosis with short-length myelitis and neuromyelitis optica spectrum disorders with longitudinally extensive transverse myelitis, multiple rare but important differential diagnoses should also be considered. Magnetic resonance imaging and laboratory analyses of serum antibodies and cerebrospinal fluid are the most important diagnostic methods and are fundamental for rapid treatment decisions, subsequently with better prognosis. This article reviews representative diseases within the spectrum of autoimmune spinal cord diseases and their differential diagnoses.

Pediatric inflammatory demyelinating disorders and mimickers: How to differentiate with MRI?

Multiple sclerosis (MS) is a chronic, immune-mediated, neurodegenerative disorder of the central nervous system (CNS).While the clinical symptoms of MS most commonly manifest between 20 and 40 years of age, approximately 3 to 10% of all MS patients report that their first inaugural events can occur earlier in life, even in childhood, and thus include the pediatric population. The prevalence of MS onset in childhood/adolescence varies between 2.0% and 4.0% of all MS cases according to several extensive studies. The main imaging patterns of pediatric inflammatory demyelinating disorders and mimicking entities, including multiple sclerosis, neuromyelitis optica spectrum disorders, acute disseminated encephalomyelitis, MOG (myelin oligodendrocyte glycoprotein) antibody-related disorders and differential diagnoses will be addressed in this article, highlighting key points to the differential diagnosis.

Differential imaging of atypical demyelinating lesions of the central nervous system

The detection of atypical and sometimes aggressive or tumefactive demyelinating lesions of the central nervous system often poses difficulties in the differential diagnosis. The clinical presentation is generally aspecific, related to the location and similar to a number of different lesions, including neoplasms and other intracranial lesions with mass effect. CSF analysis may also be inconclusive, especially for lesions presenting as a single mass at onset. As a consequence, a brain biopsy is frequently performed for characterization. Advanced MRI imaging plays an important role in directing the diagnosis, reducing the rate of unnecessary biopsies and allowing a prompt start of therapy that is often crucial, especially in the case of infratentorial lesions. In this review, the main pattern of presentation of atypical inflammatory demyelinating diseases is discussed, with particular attention on the differential diagnosis and how to adequately define the correct etiology.

Dysphagia in neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein antibody disease as a surrogate of brain involvement?

BACKGROUND AND PURPOSE

Neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein antibody disease (MOGAD) are demyelinating disorders that typically affect the optic nerves and the spinal cord. However, recent studies have demonstrated various forms of brain involvement indicating encephalitic syndromes, which consequently are included in the diagnostic criteria for both. Swallowing is processed in a distributed brain network and is therefore disturbed in many neurological diseases. The aim of this study was to investigate the occurrence of oropharyngeal dysphagia in NMOSD and MOGAD using flexible endoscopic evaluation of swallowing (FEES) as a surrogate parameter of brain involvement.

METHODS

Thirteen patients with NMOSD and MOGAD (mean age 54.2 ± 18.6 years, six men) who received FEES during clinical routine were retrospectively reviewed. Their extent of oropharyngeal dysphagia was rated using an ordinal dysphagia severity scale. FEES results were compared to a control group of healthy individuals. Dysphagia severity was correlated with the presence of clinical and radiological signs of brain involvement, the Expanded Disability Status Scale (EDSS) and the occurrence of pneumonia.

RESULTS

Oropharyngeal dysphagia was present in 8/13 patients, including six patients without other clinical indication of brain involvement. Clinical or subclinical swallowing impairment was significantly more severe in patients with NMOSD and MOGAD compared to the healthy individuals (p = 0.009) and correlated with clinical signs of brain involvement (p = 0.038), higher EDSS (p = 0.006) and pneumonia (p = 0.038).

CONCLUSION

Oropharyngeal dysphagia can occur in NMOSD and MOGAD and might be associated with pneumonia and disability. FEES may help to detect subclinical brain involvement.

MOG antibody associated disorder (MOGAD)

The existence of antibodies to myelin oligodendrocyte glycoprotein (MOG) in some patients with CNS demyelinating disease has been recognised for 30 years, but their clinical utility as biomarkers, and potential pathogenicity in humans has only become apparent in the past 15 years. The advent of more precise live cell-based assays for antibody detection in serum and cerebrospinal fluid (CSF) has greatly refined the clinical phenotype of demyelinating diseases associated with MOG antibodies. Distinct patterns of MOG antibody associated disorder (MOGAD) include acute disseminated encephalomyelitis (ADEM) in children; and overlap with neuromyelitis optica spectrum disorders (including classical Devic’s presentations), optic neuritis, transverse myelitis, and focal encephalitis in both children and adults. A number of other rare presentations have also been described. Here we summarise what is currently known of the pathophysiology, clinical presentation and management of MOGAD.

MRI signs of CNS demyelinating diseases

The differential diagnosis of the central nervous system (CNS) demyelinating diseases can be greatly facilitated by visualization and appreciation of pathognomonic radiological signs, visualized on magnetic resonance imaging (MRI) sequences. Given the distinct therapeutic approaches for each of these diseases, a decisive and reliable diagnosis in patients presenting with demyelination-associated symptoms is of crucial value. Multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) are major examples of such conditions, each possessing a number of MRI signs, closely associated with the disorder. This pictorial review aims to describe seventeen pathognomonic MRI signs associated with several CNS demyelinating disorders including MS, NMOSD, myelin oligodendrocyte glycoprotein-associated disease, Baló's concentric sclerosis, metachromatic leukodystrophy, progressive multifocal leukoencephalopathy, and neurosarcoidosis.

Anti-myelin oligodendrocyte glycoprotein antibody-positive coursing with optic neuritis: Imaging and clinical implications

A 9-year-old boy was admitted to our institution with acute onset of bilateral blurry vision. Physical examination revealed bilateral papilledema. Cerebrospinal fluid analysis and comprehensive metabolic panel were normal. Magnetic resonance imaging (MRI) of the brain showed extensive bilateral optic nerve inflammation with post-contrast gadolinium enhancement on T1-weighted sequence. The involvement was limited to the anterior segments of the optic nerves sparing chiasma and optic tracts. Anti-aquaporin-4 antibody (AQP4) was negative while anti-myelin oligodendrocyte glycoprotein antibody (MOG) was positive. After intravenous methylprednisolone, his vision dramatically improved. The patient was discharged with only mildly impaired visual acuity, 2 weeks after admission. Follow-up brain MRI and MOG assay after 3 months were within normal limits.

Neuromyelitis optica

Neuromyelitis optica (NMO; also known as Devic syndrome) is a clinical syndrome characterized by attacks of acute optic neuritis and transverse myelitis. In most patients, NMO is caused by pathogenetic serum IgG autoantibodies to aquaporin 4 (AQP4), the most abundant water-channel protein in the central nervous system. In a subset of patients negative for AQP4-IgG, pathogenetic serum IgG antibodies to myelin oligodendrocyte glycoprotein, an antigen in the outer myelin sheath of central nervous system neurons, are present. Other causes of NMO (such as paraneoplastic disorders and neurosarcoidosis) are rare. NMO was previously associated with a poor prognosis; however, treatment with steroids and plasma exchange for acute attacks and with immunosuppressants (in particular, B cell-depleting agents) for attack prevention has greatly improved the long-term outcomes. Recently, a number of randomized controlled trials have been completed and the first drugs, all therapeutic monoclonal antibodies, have been approved for the treatment of AQP4-IgG-positive NMO and its formes frustes.

MRI characteristics of MOG-Ab associated disease in adults: An update

Our knowledge of the radiological spectrum of myelin oligodendrocyte glycoprotein antibody associated disease (MOGAD) is growing rapidly. An update on the radiological features of the disease, and its evolution is thus necessary. Magnetic resonance imaging (MRI) has an increasingly important role in the differential diagnosis of MOGAD particularly from aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (AQP4-NMOSD), and multiple sclerosis (MS). Differentiating these conditions is of prime importance because the management is different between the three inflammatory diseases, and thus could prevent further attack-related disability. Therefore, identifying the MRI features suggestive of MOGAD has diagnostic and prognostic implications. We herein review optic nerve, spinal cord and the brain MRI findings from MOGAD adult patients, and compare them to AQP4-NMOSD and MS.