Optic neuritis and mydriasis after vaccination: a case report.

BACKGROUND: Optic neuritis (ON) is an inflammatory demyelinating condition of the optic nerve, with various causes. Its incidence is higher in children and young adults than in older adults of both genders, but is more common in women than in men. ON is rarely associated with mydriasis, and it is seldom triggered by vaccines against tetanus and diphtheria. CASE REPORT: A 36-year-old Caucasian woman presented with bilateral ON that had started 18 days after administration of a booster dose of the double adult vaccine (dT) against diphtheria and tetanus. Bilateral mydriasis persisted after treatment and clinical resolution of the ON. She experienced severe headache, blurred vision, decreased visual acuity in the right eye and bilateral mydriasis, a diagnosis confirmed by imaging tests. Treatment with oral corticosteroids resulted in rapid resolution of the neuritis; however, mydriasis persisted for several months. CONCLUSION: This study describes a very unusual case of bilateral ON associated with prolonged mydriasis after vaccination against tetanus and diphtheria that regressed after treatment with oral corticosteroids. Prolonged mydriasis was the manifestation that differed from the other cases previously described.

Relationship between pattern reversal visual evoked potential P100 wave latency and dysfunctional HDL in patients with multiple sclerosis subjected to an optic neuritis attack: A case-control study.

Optic neuritis frequently occurs during the clinical course of multiple sclerosis (MS). In this condition, demyelination of the optic nerve occurs, which electrophysiologically causes a delay in P100 wave latency. Sensitive cholesterol homeostasis is critical for the formation of the myelin sheath and for myelin to become functionally mature. High-density lipoprotein (HDL) becomes dysfunctional under oxidative stress and plays an important role in the pathogenesis of MS. In this study, HDL levels of MS patients suffering from optic neuritis were compared with those of healthy individuals, and the relationship between pattern reversal visual evoked potential (PRVEP) P100 wave latency and HDL levels in patients with optic neuritis attacks was analyzed. PRVEP studies were performed in patients with MS who had an episode of optic neuritis, and P100 wave latencies were measured. Peripheral blood samples were collected from healthy participants and patients. Lipid levels and myeloperoxidase (MPO) and paraoxonase (PON) activities were measured, and the MPO/PON ratio was then calculated. The lipid profiles and dysfunctional HDL levels in the healthy and patient groups were compared. Finally, the relationship between these parameters and the PRVEP-P100 wave latency was examined. Total cholesterol and low-density lipoprotein (LDL) levels were significantly higher in the patient group (P = .044; P = .038, respectively). There was no statistically significant difference in HDL levels between groups (P = .659). The distribution of MPO values was similar between groups (P = .452). PON values were significantly lower, whereas the MPO/PON ratios were significantly higher in the patient group than in the control group (P = .025; P = .028, respectively). A statistically significant positive correlation was found between the elevated MPO/PON ratio, representing dysfunctional HDL, and both the mean and maximum PRVEP-P100 wave latencies (P < .001, R = 0.690; P < .001, R = 0.815, respectively). A dysfunctional form of HDL may lead to poor deactivation of remyelination-limiting factors and may ultimately be associated with poor outcomes in optic neuritis.

Myelin oligodendrocyte glycoprotein (MOG) associated optic neuritis in a patient with idiopathic intracranial hypertension (IIH) and compressive optic neuropathy case report.

BACKGROUND: Myelin oligodendrocyte glycoprotein-associated disease (MOGAD) has a wide phenotypic expression and should be considered in a differential diagnosis of patients with optic disc edema and increased intracranial pressure because MOGAD can mimic IIH and compressive optic neuropathy. CASE PRESENTATION: A 53-year-old woman with a history of presumed idiopathic intracranial hypertension ("IIH") presented with new headache and visual loss. She had a BMI of 35.44 kg/m2 and a past medical history significant for depression, hepatitis C, hyperlipidemia, and uterine cancer post-hysterectomy. She had undergone multiple lumboperitoneal shunts for presumed IIH and had a prior pituitary adenoma resection. Her visual acuity was no light perception OD and counting fingers OS. After neuro-ophthalmic consultation, a repeat cranial MRI showed symmetric thin peripheral optic nerve sheath enhancement of the intra-orbital optic nerves OU. Serum MOG antibody was positive at 1:100 and she was treated with intravenous steroids followed by plasma exchange and rituximab. CONCLUSIONS: This case highlights the importance of considering MOGAD in the differential diagnosis of optic neuropathy. Although likely multifactorial, we believe that the lack of improvement in our case from presumed IIH and despite adequate neurosurgical decompression of a pituitary adenoma with compression of the optic apparatus reflected underlying unrecognized MOGAD. Clinicians should consider repeat imaging of the orbit (in addition to the head) in cases of atypical IIH or compressive optic neuropathy especially when the clinical course or response to therapy is poor or progressive.

Optic Nerve MRI T2-Hyperintensity: A Nonspecific Marker of Optic Nerve Damage.

BACKGROUND: MRI abnormalities are common in optic neuropathies, especially on dedicated orbital imaging. In acute optic neuritis, optic nerve T2-hyperintensity associated with optic nerve contrast enhancement is the typical imaging finding. In chronic optic neuropathies, optic nerve T2-hyperintensity and atrophy are regularly seen. Isolated optic nerve T2-hyperintensity is often erroneously presumed to reflect optic neuritis, frequently prompting unnecessary investigations and neuro-ophthalmology consultations. Our goal was to determine the significance of optic nerve/chiasm T2-hyperintensity and/or atrophy on MRI. METHODS: Retrospective study of consecutive patients who underwent brain/orbital MRI with/without contrast at our institution between July 1, 2019, and June 6, 2022. Patients with optic nerve/chiasm T2-hyperintensity and/or atrophy were included. Medical records were reviewed to determine the etiology of the T2-hyperintensity and/or atrophy. RESULTS: Four hundred seventy-seven patients (698 eyes) were included [mean age 52 years (SD ±18 years); 57% women]. Of the 364 of 698 eyes with optic nerve/chiasm T2-hyperintensity without atrophy, the causes were compressive (104), inflammatory (103), multifactorial (49), glaucoma (21), normal (19), and other (68); of the 219 of 698 eyes with optic nerve/chiasm T2-hyperintensity and atrophy, the causes were compressive (57), multifactorial (40), inflammatory (38), glaucoma (33), normal (7), and other (44); of the 115 of 698 eyes with optic nerve/chiasm atrophy without T2-hyperintensity, the causes were glaucoma (34), multifactorial (21), inflammatory (13), compressive (11), normal (10), and other (26). Thirty-six eyes with optic nerve/chiasm T2-hyperintensity or atrophy did not have evidence of optic neuropathy or retinopathy on ophthalmologic examination, and 17 eyes had clinical evidence of severe retinopathy without primary optic neuropathy. CONCLUSIONS: Optic nerve T2-hyperintensity or atrophy can be found with any cause of optic neuropathy and with severe chronic retinopathy. These MRI findings should not automatically prompt optic neuritis diagnosis, workup, and treatment, and caution is advised regarding their use in the diagnostic criteria for multiple sclerosis. Cases of incidentally found MRI optic nerve T2-hyperintensity and/or atrophy without a known underlying optic neuropathy or severe retinopathy are rare. Such patients should receive an ophthalmologic examination before further investigations.

Rare Combination of Abducens Nerve Palsy and Optic Neuritis on the Same Side: Case Report and Review of 8 Patients in Literature.

The concurrent development of abducens nerve palsy and optic neuritis on the same side is rare. Here we presented an 82-year-old man who developed the combination of abducens nerve palsy and optic neuritis on the left side 2 months after the sixth inoculation of COVID-19 mRNA vaccine. In past history at 45 years old, he experienced subarachnoid hemorrhage and underwent surgery for the clipping of intracranial aneurysm. The patient had no systemic symptoms, such as general fatigue, fever, arthralgia, and skin rashes. Physical and neurological examinations were also unremarkable. Since the aneurysmal metal clip used at that time was not compatible with magnetic resonance imaging, he underwent computed tomographic (CT) scan of the head and showed no space-occupying lesion in the orbit, paranasal sinuses, and brain. As an old lesion, the anterior temporal lobe on the left side had low-density area with metallic artifact on the left side of the skull base, indicative of metal clipping. In 4 weeks of observation from the initial visit, he showed complete recovery of visual acuity and became capable of abducting the left eye in full degrees. We also reviewed 8 patients with the combination of abducens nerve palsy and optic neuritis in the literature to reveal that the combination of signs did occur in mild meningitis with rare infectious diseases and in association with preceding herpes zoster in the first branch of the trigeminal nerve. The course of the present patient suggested that the combination of signs might be vaccine-associated.

Prevalence of serum MOG antibody and AQP4 antibody in optic neuritis after SARS-CoV-2 infection.

Purpose: To evaluate the prevalence of serum myelin oligodendrocyte glycoprotein antibody (MOG-Ab) and aquaporin-4 antibody (AQP4-Ab) in optic neuritis (ON) patients after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection by cell-based indirect immunofluorescence assay (CBA). Methods: In this prospective case series study, 35 patients clinically diagnosed as ON and laboratory-confirmed SARS-CoV-2 infection from 8 December 2022 to 8 February 2023 were included. All patients' clinical and laboratory data were collected and analyzed. Results: The mean age of the 35 patients (46 eyes) was 38.2 years (ranging from 6 to 69 years), and 17 cases were female patients. Thirty-three and two cases showed positive SARS-CoV-2 RNA test results before or shortly after ON onset, respectively. ON occurred unilaterally in 24 cases and bilaterally in 11 cases. Ophthalmic examination revealed swollen optic disc in 37 eyes, normal optic disc in 6 eyes, and temporally or wholly paled optic disc in 3 eyes. CBA revealed seropositive MOG-Ab in 10 cases and AQP4-Ab in 2 cases, respectively, of which 2 AQP4-Ab-seropositive cases and 1 MOG-Ab-seropositive case had a past medical history of ON. Most ON patients showed a rapid and dramatic response to pulse steroid therapy. The median of BCVA at the onset and at the last follow-up was 20/500 (ranging from light perception to 20/20) and 20/67 (ranging from counting fingers to 20/20), respectively. Conclusion: Serum MOG-Ab and AQP4-Ab were detected in 28.6% (10/35) and 5.7% (2/35) ON cases after SARS-CoV-2 infection. SARS-CoV-2 infection may trigger an onset or a relapse of ON, as well as the production of MOG-Ab.

Beyond Myelin Oligodendrocyte Glycoprotein and Aquaporin-4 Antibodies: Alternative Causes of Optic Neuritis.

Optic neuritis (ON) is the most common cause of vision loss in young adults. It manifests as acute or subacute vision loss, often accompanied by retrobulbar discomfort or pain during eye movements. Typical ON is associated with Multiple Sclerosis (MS) and is generally mild and steroid-responsive. Atypical forms are characterized by unusual features, such as prominent optic disc edema, poor treatment response, and bilateral involvement, and they are often associated with autoantibodies against aquaporin-4 (AQP4) or Myelin Oligodendrocyte Glycoprotein (MOG). However, in some cases, AQP4 and MOG antibodies will return as negative, plunging the clinician into a diagnostic conundrum. AQP4- and MOG-seronegative ON warrants a broad differential diagnosis, including autoantibody-associated, granulomatous, and systemic disorders. These rare forms need to be identified promptly, as their management and prognosis are greatly different. The aim of this review is to describe the possible rarer etiologies of non-MS-related and AQP4- and MOG-IgG-seronegative inflammatory ON and discuss their diagnoses and treatments.

SARS-CoV-2 Parainfectious Optic Neuropathy: 3 Case Reports and a Review of the Literature.

BACKGROUND: Parainfectious optic neuritis is an inflammatory reaction that occurs shortly after an infection without direct invasion by a pathogen. The clinical profile depends on the infectious organism. Cases of SARS-CoV-2 parainfectious optic neuritis have been reported in the literature, but there are no reviews that have applied strict inclusion criteria to more definitively establish the clinical profile associated with SARS-CoV-2. METHODS: We present 3 new cases of SARS-CoV-2 parainfectious optic neuritis. We also review the literature for definite cases by selecting only those with unambiguous clinical features and MRI findings of optic neuritis, positive SARS-CoV-2 polymerase chain reaction or serology, and the absence of myelin oligodendrocyte-glycoprotein or aquaporin-4 antibodies or other diseases associated with optic neuritis. RESULTS: We report 2 cases of monophasic, unilateral SARS-CoV-2 parainfectious optic neuritis with optic disc edema and nadir visual acuities of finger counting. We report 1 case of mild SARS-CoV-2 parainfectious optic neuritis that featured cotton wool spots, peripapillary wrinkles and hemorrhages, and recurrence after an initial steroid taper. We identified 6 cases of unambiguous SARS-CoV-2 parainfectious optic neuritis from the literature. Combining our case series with the case reports in the literature, the average age was 42.8 years, 3/9 had bilateral disease, 6/8 had optic disc edema, 8/9 had nadir visual acuity of finger counting or worse, and all recovered visual acuity to 20/40 or better after therapy with steroids. CONCLUSIONS: SARS-CoV-2 parainfectious optic neuritis has a clinical profile that is atypical for idiopathic optic neuritis but fairly typical of parainfectious forms of optic neuritis with a severely reduced nadir visual acuity, high likelihood of bilaterality, high incidence of optic disc edema, and prompt and significant response to corticosteroids. Further study with long-term follow-up and epidemiologic investigation will be needed to further characterize this clinical entity.

Myelin oligodendrocyte glycoprotein antibody-associated optic neuritis in a post-COVID-19 infection patient.

PURPOSE: SARS-CoV-2 viral infection affects multiple systems including the respiratory, gastrointestinal, neurological, cardiac, and ophthalmic systems. We report a case of myelin oligodendrocyte glycoprotein (MOG) related optic neuritis in a SARS-CoV-2 (COVID-19) patient. METHODS: Case report. RESULTS: A 36-year-old Malay gentleman with underlying hypertension presented with the first episode of bilateral progressively worsening blurred vision for 1 week associated with retrobulbar pain. There were no other neurological symptoms. He had fever a week before the eye symptoms and tested positive for COVID-19. He received COVID-19 booster vaccine a month before the disease onset. On examination, his vision was hand motion on right eye and 6/18 on left eye. Relative afferent pupillary defect (RAPD) was positive on right eye with abnormal optic nerve function tests. Anterior segments were unremarkable. Fundus examination showed bilateral optic disc swelling. MRI revealed multifocal hyperintense subcortical white matter lesions. Optic nerves appeared normal with no enhancement seen. Blood investigation showed a positive serum MOG antibody. Intravenous methylprednisolone was commenced followed by oral prednisolone after which his vision and ocular symptoms markedly improved. The oral prednisolone was tapered alongside addition of azathioprine. At 1 month, the disease was stable with no recurrence. CONCLUSION: While optic neuritis has been associated with both COVID-19 infection and vaccination, MOG IgG antibody-mediated optic neuritis is also a possible manifestation. This type of optic neuritis associated with COVID-19 infection does not show a similar pattern of frequent recurrences as seen in non-COVID-19 related optic neuritis.

[Combination of post-infectious optic neuritis and Guillain-Barré syndrome]. / Sochetanie postinfektsionnogo nevrita zritel'nykh nervov i sindroma Giiena­Barre.

The coexistence of optic neuritis and Guillain-Barré syndrome is a rare combination of neurological diseases. The trigger of an autoimmune inflammatory process is often a respiratory mycoplasma infection. Ignorance of such combination can lead to diagnostic and therapy mistakes. This article describes the case of a rare combination of overlapping optic neuritis and Guillain-Barré syndrome, associated with Mycoplasma pneumoniae and provides the short literature review. Further studies are required to identify common pathogenetic mechanisms of combined inflammatory lesions of the optic nerves and peripheral nervous system.

An update on optic neuritis.

Optic neuritis (ON) is the most common cause of subacute optic neuropathy in young adults. Although most cases of optic neuritis (ON) are classified as typical, meaning idiopathic or associated with multiple sclerosis, there is a growing understanding of atypical forms of optic neuritis such as antibody mediated aquaporin-4 (AQP4)-IgG neuromyelitis optica spectrum disorder (NMOSD) and the recently described entity, myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD). Differentiating typical ON from atypical ON is important because they have different prognoses and treatments. Findings of atypical ON, including severe vision loss with poor recovery with steroids or steroid dependence, prominent optic disc edema, bilateral vision loss, and childhood or late adult onset, should prompt serologic testing for AQP4-IgG and MOG-IgG. Although the traditional division of typical and atypical ON can be helpful, it should be noted that there can be severe presentations of otherwise typical ON and mild presentations of atypical ON that blur these traditional lines. Rare causes of autoimmune optic neuropathies, such as glial fibrillary acidic protein (GFAP) and collapsin response-mediator protein 5 (CRMP5) autoimmunity also should be considered in patients with bilateral painless optic neuropathy associated with optic disc edema, especially if there are other accompanying suggestive neurologic symptoms/signs. Typical ON usually recovers well without treatment, though recovery may be expedited by steroids. Atypical ON is usually treated with intravenous steroids, and some forms, such as NMOSD, often require plasma exchange for acute attacks and long-term immunosuppressive therapy to prevent relapses. Since treatment is tailored to the cause of the ON, elucidating the etiology of the ON is of the utmost importance.

[Hereditary optic neuropathy associated with demyelinating diseases of the central nervous system]. / Nasledstvennaya opticheskaya neiropatiya v sochetanii s demieliniziruyushchimi zabolevaniyami tsentral'noi nervnoi sistemy.

Demyelinating optic neuritis and hereditary optic neuropathy (HON) take a leading place among the diseases, the leading clinical syndrome of which is bilateral optic neuropathy with a simultaneous or sequential significant decrease in visual acuity. Optic neuritis can occur at the onset or be one of the syndromes within multiple sclerosis (MS), neuromyelitis optica spectrum disorders (NMOSD), and myelin oligodendrocyte glycoprotein (MOG) antibody disease (MOGAD). HON are a group of neurodegenerative diseases, among which the most common variants are Leber's hereditary optic neuropathy (LHON), associated with mitochondrial DNA (mtDNA) mutations, and autosomal recessive optic neuropathy (ARON), caused by nuclear DNA (nDNA) mutations in DNAJC30. There are phenotypes of LHON «plus¼, one of which is the association of HON and CNS demyelination in the same patient. In such cases, the diagnosis of each of these diseases causes significant difficulties, due to the fact that in some cases there are clinical and radiological coincidences between demyelinating and hereditary mitochondrial diseases.

MOG-specific T cell response amplified in para- and post-SAR-CoV-2 infection in myelin oligodendrocyte glycoprotein antibody-associated disease.

We describe clinical characteristics and deep immunophenotypes in two patients with myelin-oligodendrocyte-glycoprotein (MOG)-antibody-associated-disease after COVID-19. The para-COVID case was a 74-year-old man who developed optic neuritis two days after COVID-19. Immunological assays revealed reduced absolute CD8+ T- and B-cell counts with increased frequency of NK cells. Post-COVID case was a 63-year-old man with optic neuritis six months after COVID-19, a frequency of CD8+ T-cells was elevated with a relatively low fraction of naïve and a high fraction of effector memory CD8+ T-cells. There was increased frequency of CD8+CD38+HLA-DR+ T-cells in the para-COVID case; interestingly, CD4+CD38+HLA-DR+ T cell frequency was increased in the post-COVID case. Both had increased SARS-CoV-2-specific and MOG-specific T-cell responses.

Optic Neuritis After COVID-19 Vaccination: An Analysis of the Vaccine Adverse Event Reporting System.

BACKGROUND: To investigate the association of optic neuritis (ON) after the COVID-19 vaccines. METHODS: Cases of ON from Vaccine Adverse Event Reporting System (VAERS) were collected and divided into the prepandemic, COVID-19 pandemic, and COVID-19 vaccine periods. Reporting rates were calculated based on estimates of vaccines administered. Proportion tests and Pearson χ 2 test were used to determine significant differences in reporting rates of ON after vaccines within the 3 periods. Kruskal-Wallis testing with Bonferroni-corrected post hoc analysis and multivariable binary logistic regression was used to determine significant case factors such as age, sex, concurrent multiple sclerosis (MS) and vaccine manufacturer in predicting a worse outcome defined as permanent disability, emergency room (ER) or doctor visits, and hospitalizations. RESULTS: A significant increase in the reporting rate of ON after COVID-19 vaccination compared with influenza vaccination and all other vaccinations (18.6 vs 0.2 vs 0.4 per 10 million, P < 0.0001) was observed. However, the reporting rate was within the incidence range of ON in the general population. Using self-controlled and case-centered analyses, there was a significant difference in the reporting rate of ON after COVID-19 vaccination between the risk period and control period ( P < 0.0001). Multivariable binary regression with adjustment for confounding variables demonstrated that only male sex was significantly associated with permanent disability. CONCLUSIONS: Some cases of ON may be temporally associated with the COVID-19 vaccines; however, there is no significant increase in the reporting rate compared with the incidence. Limitations of this study include those inherent to any passive surveillance system. Controlled studies are needed to establish a clear causal relationship.

Regional Analysis of Inner Retinal Layer Changes in Multiple Sclerosis with and without Optic Neuritis.

Objectives: The study aimed to investigate inner retinal changes in multiple sclerosis (MS) patients by comparing them with healthy controls. The study also aimed to assess regional differences of inner retinal layer involvement in eyes with and without optic neuritis (ON). Materials and Methods: This retrospective, cross-sectional study consisted of 141 eyes of 74 relapsing-remitting MS patients and 80 eyes of 40 healthy controls. The study group was separated into two subgroups according to the presence of ON history. Peripapillary retinal nerve fiber layer (pRNFL) thickness, total macular thickness, and thicknesses of the macular retinal nerve fiber layer (mRNFL), ganglion cell layer (GCL), inner plexiform layer (IPL), and inner nuclear layer were compared between the MS and healthy control groups and between eyes with and without ON history. Results: Mean pRNFL, total macular, mRNFL, GCL, and IPL thicknesses were significantly thinner in the MS group than in the control group (p<0.001) and in eyes with ON compared to those without ON (p<0.05). Comparison of inner retinal layer thicknesses in the inner 3-mm ring subfields of the ETDRS grid revealed significant thinning in all subfields of the GCL and IPL of eyes with ON (p<0.05). The inferior subfield demonstrated the highest difference. Conclusion: The study demonstrated that GCL and IPL thinning is a robust and reliable biomarker in all MS patients. The thinning was significantly greater in eyes with ON than in eyes without ON. The study also documented that the inferior region showed significantly greater GCL and IPL thinning in eyes with previous ON attacks.

Real-world application of the 2022 diagnostic criteria for first-ever episode of optic neuritis.

Optic neuritis (ON) admits diverse differential diagnoses. Petzold proposed diagnostic criteria for ON in 2022, although real-world application of these criteria is missing. We conducted a retrospective review of patients with ON. We classified patients into definite or possible ON, and into groups A (typical neuritis), B (painless), or C (binocular) and estimated the frequency of etiologies for each group. We included 77 patients, with 62% definite and 38% possible ON. CRION and NMOSD-AQP4 negative-ON were less commonly seen in definite ON. Application of the 2022 criteria revealed a lower-than-expected frequency of definite ON, particularly for seronegative non-MS causes.

Neuro-Ophthalmic Visual Impairment in the Setting of COVID-19.

We set out to describe in detail the afferent neuro-ophthalmological complications that have been reported in association with coronavirus disease 2019 (COVID-19) infection. We describe and elaborate on mechanisms of disease, including para-infectious inflammation, hypercoagulability, endothelial damage, and direct neurotropic viral invasion. Despite global vaccination programs, new variants of COVID-19 continue to pose an international threat, and patients with rare neuro-ophthalmic complications are likely to continue to present for care.Afferent complications from COVID-19 include homonymous visual field loss, with or without higher cortical visual syndromes, resulting from stroke, intracerebral hemorrhage, or posterior reversible leukoencephalopathy. Optic neuritis has frequently been reported, sometimes along with acute disseminated encephalomyelopathy, often in association with either myelin oligodendrocyte glycoprotein antibodies (MOG-IgG) or less commonly aquaporin-4 seropositivity or in newly diagnosed multiple sclerosis. Ischemic optic neuropathy has rarely been reported. Papilledema, resulting either from venous sinus thrombosis or idiopathic intracranial hypertension in the setting of COVID-19, has also been described.Observed afferent neuro-ophthalmic associations need to be confirmed though larger comparative studies. Meanwhile, the range of possible complications should be recognized by neurologists and ophthalmologists alike, to facilitate faster diagnosis and treatment of both COVID-19 and its neuro-ophthalmic manifestations.

Acute optic neuritis: What are the clues to the aetiological diagnosis in real life?

BACKGROUND: Previous cross-sectional studies have reported distinct clinical and radiological features among the different acute optic neuritis (ON) aetiologies. Nevertheless, these reports often included the same number of patients in each group, not taking into account the disparity in frequencies of ON aetiologies in a real-life setting and thus, it remains unclear what are the truly useful features for distinguishing the different ON causes. To determine whether clinical evaluation, ophthalmological assessment including the optical coherence tomography (OCT), CSF analysis, and MRI imaging may help to discriminate the different causes of acute ON in a real-life cohort. METHODS: In this prospective monocentric study, adult patients with recent acute ON (<1 month) underwent evaluation at baseline and 1 and 12 months, including, high- and low-contrast visual acuity, visual field assessment and OCT measurements, baseline CSF analysis and MRI. RESULTS: Among 108 patients, 71 (65.7%) had multiple sclerosis (MS), 19 (17.6%) had idiopathic ON, 13 (12.0%) and 5 (4.6%) had myelin oligodendrocyte glycoprotein and aquaporin-4 antibodies, at last follow up respectively.At baseline, the distribution of bilateral ON, CSF-restricted oligoclonal bands, optic perineuritis, optic nerve length lesions and positive dissemination in space and dissemination in time criteria on MRI were significantly different between the four groups (p <0.001). No significant difference in visual acuity nor inner retinal layer thickness was found between the different ON aetiologies. CONCLUSIONS: In this large prospective study, bilateral visual involvement, CSF and MRI results are the most useful clues in distinguishing the different aetiologies of acute ON, whereas ophthalmological assessments including OCT measurements revealed no significant difference between the aetiologies.

[Optic neuropathies as an interdisciplinary subject of research]. / Opticheskie neiropatii kak predmet mezhdistsiplinarnogo izucheniya.

Despite the wide range of clinical, instrumental and laboratory methods used in modern ophthalmology, the problem of diagnosing optic neuropathy and identifying its etiology remains relevant. A complex multidisciplinary approach involving various specialists is required in the differential diagnosis of immune-mediated optic neuritis, for example in multiple sclerosis, neuromyelitis optica spectrum disorder, and MOG-associated diseases. Of special interest is differential diagnosis of optic neuropathy in demyelinating diseases of the central nervous system, hereditary optic neuropathies and ischemic optic neuropathy. The article presents a summary of scientific and practical results of differential diagnosis of optic neuropathies with various etiologies. Timely diagnosis and early therapy start reduces the degree of disability in patients with optic neuropathies of different etiologies.

Alleviating early demyelination in ischaemia/reperfusion by inhibiting sphingosine-1-phosphate receptor 2 could protect visual function from impairment.

Retinal ischaemia/reperfusion (I/R) injury is a common cause of retinal ganglion cell (RGC) apoptosis and axonal degeneration, resulting in irreversible visual impairment. However, there are no available neuroprotective and neurorestorative therapies for retinal I/R injury, and more effective therapeutic approaches are needed. The role of the myelin sheath of the optic nerve after retinal I/R remains unknown. Here, we report that demyelination of the optic nerve is an early pathological feature of retinal I/R and identify sphingosine-1-phosphate receptor 2 (S1PR2) as a therapeutic target for alleviating demyelination in a model of retinal I/R caused by rapid changes in intraocular pressure. Targeting the myelin sheath via S1PR2 protected RGCs and visual function. In our experiment, we observed early damage to the myelin sheath and persistent demyelination accompanied by S1PR2 overexpression after injury. Blockade of S1PR2 by the pharmacological inhibitor JTE-013 reversed demyelination, increased the number of oligodendrocytes, and inhibited microglial activation, contributing to the survival of RGCs and alleviating axonal damage. Finally, we evaluated the postoperative recovery of visual function by recording visual evoked potentials and assessing the quantitative optomotor response. In conclusion, this study is the first to reveal that alleviating demyelination by inhibiting S1PR2 overexpression may be a therapeutic strategy for retinal I/R-related visual impairment.