Optic Neuritis: An Update Typical and Atypical Optic Neuritis

Atypical Optic Neuritis: The Potential Red Flags

BACKGROUND

Many potential causes of optic nerve inflammation exist, including typical and atypical causes, which require different management strategies.

OBJECTIVE

The objective of this study is to identify red flags that help differentiate typical from atypical optic neuritis (ON).

MATERIALS AND METHODS

This prospective study included 66 patients (100 eyes) with immune-mediated ON from January 2016 to June 2019, carefully excluding the nonimmune causes. The clinico-radiological features, investigations, therapy, and outcome were analyzed.

RESULTS

We evaluated 33 cases each of typical and atypical ON. The typical group included 29 idiopathic ON and four associated with multiple sclerosis. Atypical ON included 19 neuromyelitis optica (NMO), seven MOG-associated ON (MOG-ON), and others due to Sjogren's syndrome, granulomatous polyangiitis, sarcoidosis, and IgG4 disease. Atypical ON occurred significantly and more frequently with extremes of ages (<10 or >70 years), bilateral simultaneous or severe vision loss with early disc pallor, multiple attacks, symptoms/neuro-imaging indicating non-MS disease e.g., long segment ON/myelitis, large confluent lesions, the involvement of optic tract, chiasma, area postrema or diencephalon, and (pachy) meningitis. Systemic involvement and poor outcomes despite steroids and second-line immunosuppression were observed more often in the atypical ON.

CONCLUSIONS

The red flags indicating atypical ON are onset at extremes of age, multiple attacks, bilateral simultaneous or severe to very severe vision loss, early disc pallor, neurological symptoms, or imaging abnormalities suggesting non-MS disease, systemic involvement, and poor steroid responsiveness. The awareness might help the clinician promptly identify and escalate therapy to ensure a better outcome.

Vision-Related Quality of Life in Patients With Atypical Optic Neuritis

Aim

To evaluate the vision-related quality of life (QOL) in patients with atypical optic neuritis through the 39-item National Eye Institute Visual Function Questionnaire (NEI VFQ-39).

Methods

Fifty-seven patients with atypical optic neuritis were scheduled in the research unit from June 1 to December 31, 2019. Besides collecting the clinical data, NEI VFQ-39, the Chinese version, was applied to all subjects. The NEI VFQ-39 subscale item scores were compared among subgroups divided by different classifications, and a correlation analysis of the NEI VFQ-39 scores and best-corrected visual acuity (BCVA) for better-seeing and worse-seeing eyes was performed.

Results

The mean age of scheduled patients was 34.3 ± 12.4 years, with the majority being female (70.2%). The mean composite score was 58.62 ± 17.62. Twenty-nine (50.9%) patients were affected binocularly, and the most subscale scores and composite scores of binocular incidences were lower than those of monocular incidence significantly. However, there was no statistically significant difference in composite scores between patients with and without periocular pain. The patients with worse BCVA in the better-seeing eye have lower scores than those with better BCVA in the better-seeing eye. Most NEI VFQ-39 scores have strong correlations with the BCVA for better-seeing and worse-seeing eyes.

Conclusion

Atypical optic neuritis has a significant and comprehensive influence on patients' visual function outcomes and quality of life associated with vision. Improving their BCVA in the better-seeing eye can improve their vision-related QOL.

Update on Optic Neuritis: An International View

Previously, optic neuritis was thought to be typical, i.e. idiopathic or multiple sclerosis (MS) related, associated with a good visual prognosis, or atypical, i.e. not associated with MS and requiring corticosteroids or plasma exchange for vision to recover. More recently, the importance of optic neuritis in neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein (MOG) antibody disease has become more appreciated. The results of the Optic Neuritis Treatment Trial (ONTT) has influenced how optic neuritis is treated around the world. For this review we surveyed the international literature on optic neuritis in adults. Our aims were first to find the reported incidence of optic neuritis in different countries and to ascertain what percentage of cases were seropositive for anti-aquaporin 4 and anti-MOG antibodies, and second, to document the presenting features, treatment, and outcomes from a first episode of the different types of optic neuritis from these countries, and to compare the results with the outcomes of the ONTT cohort. From these data we have sought to highlight where ambiguities currently lie in how to manage optic neuritis and have made recommendations as to how future treatment trials in optic neuritis should be carried out in the current antibody testing era.

Optic neuritis induced by 5-fluorouracil chemotherapy: Case report and review of the literature

Introduction

For over 50 years, 5-Fluorouracil has played a critical role in the treatment of numerous malignancies, including colorectal cancer. Ocular side effects are uncommon and include blurred vision, conjunctivitis, excessive lacrimation and keratitis.

Case report

We report a 57-year-old male with metastatic colorectal cancer who had received extensive chemotherapy with 5-Fluorouracil-based regimens for over 12 months. Following his seventh cycle of cetuximab/FOLFIRI, he developed acute onset global headache, nausea and loss of vision in the right eye. After detailed investigations, including ophthalmologic and neurologic consultations, a diagnosis of optic neuritis was made.

Management and outcome

Chemotherapy was ceased immediately, and intravenous methylprednisolone (1 g) daily for five days was commenced. His headache resolved and vision started to improve within 24 h. Three weeks after completion of corticosteroids, constriction of the right visual field had fully resolved.

Discussion

Atypical optic neuritis is an inflammatory optic neuropathy that can be caused by ischaemia, mechanical compression, nutritional deficiency, toxins and drugs. Drug-induced optic neuritis, while rare, is associated with cytotoxic medications including methotrexate, cisplatin, carboplatin, vincristine and paclitaxel. There have only been five previous case reports implicating 5-Fluorouracil in the development of optic neuropathy. The likelihood of the adverse drug reaction due to 5-Fluorouracil was assessed using the Naranjo algorithm. A score of +7 indicates probable causality. Clinicians should be alert to this potential ocular toxicity in order to initiate prompt cessation of treatment and early ophthalmology referral to prevent visual loss and damage to ocular structures.

Bilateral Optic Perineuritis as Initial Presentation of Giant Cell Arteritis

Giant cell arteritis is a large vessel vasculitis with neurological manifestations that range from visual disturbances to ischemic stroke. Among the former, visual acuity and visual field defects are prevalent, with anterior ischemic optic neuropathy being their most frequent cause. We present a clinical case in which the presenting ocular feature of the disease was a peripheral monocular visual field defect secondary to optic perineuritis.

Baseline demographics, clinical features, and treatment protocols of 240 patients with optic neuropathy: experiences from a neuro-ophthalmological clinic in the Aegean region of Turkey

PURPOSE

To analyze the demographic patterns, clinical characteristics, and treatment protocols of optic neuropathies.

MATERIALS AND METHODS

The hospital data of patients with optic neuropathy admitted to the Department of Neuro-ophthalmology in a tertiary referral center in Turkey between January 2010 to January 2017 were retrospectively analyzed. Demographic patterns, clinical features, treatment protocols, and the natural disease courses were assessed.

RESULTS

The total number of patients with optic neuropathy seen over this period was 240, which consist of 43 with idiopathic optic neuritis (17.9%), 40 with multiple sclerosis-related optic neuritis (16.7%), 12 with chronic relapsing inflammatory optic neuritis (5.0%), 12 with atypical optic neuritis (5.0%), 11 with neuromyelitis optica spectrum disorders-related optic neuritis (4.6%), 90 with non-arteritic ischemic optic neuropathy (37.5%), 4 with arteritic ischemic optic neuropathy (1.7%), 10 with traumatic optic neuropathy (4.1%), 6 with compressive optic neuropathy (2.5%), and 12 with mitochondrial optic neuropathy [9 with toxic optic neuropathy (3.7%) and 3 with Leber's hereditary optic neuropathy (1.2%)]. There were 101 males (42%) and 139 females (58%). The mean age was 43.34 ± 15.86 years.

CONCLUSION

This study reported the demographics, clinical characteristics, and treatment protocols of optic neuropathies in a neuro-ophthalmology specialty clinic at a tertiary referral center in Turkey during the past decade. The data may be useful in assessing the global status of optic neuropathies.

Optic Perineuritis

Optic perineuritis (OPN) is now defined as "a form of idiopathic orbital inflammatory disease, in which the specific target tissue is the optic nerve sheath". It may be idiopathic or may occur as part of an underlying systemic inflammatory disease. It is a rare disorder and information regarding its presentation and management is only available in case reports and small case series. This review will discuss the contribution of these recent articles to what is known about idiopathic and secondary OPN. Suggestions will also be made as to how to investigate and treat a patient presenting with OPN.

Amiloride Clinical Trial In Optic Neuritis (ACTION) protocol: a randomised, double blind, placebo controlled trial

INTRODUCTION

Neurodegeneration is a widely accepted contributor to the development of long-term disability in multiple sclerosis (MS). While current therapies in MS predominantly target inflammation and reduce relapse rate they have been less effective at preventing long-term disability. The identification and evaluation of effective neuroprotective therapies within a trial paradigm are key unmet needs. Emerging evidence supports amiloride, a licenced diuretic, as a neuroprotective agent in MS through acid sensing ion channel blockade. Optic neuritis (ON) is a common manifestation of MS with correlates of inflammation and neurodegeneration measurable within the visual pathways. Amiloride Clinical Trial In Optic Neuritis (ACTION) will utilise a multimodal approach to assess the neuroprotective efficacy of amiloride in acute ON.

METHODS AND ANALYSIS

46 patients will be recruited within 28 days from onset of ON visual symptoms and randomised on a 1:1 basis to placebo or amiloride 10 mg daily. Double-blinded treatment groups will be balanced for age, sex and visual loss severity by a random-deterministic minimisation algorithm. The primary objective is to demonstrate that amiloride is neuroprotective in ON as assessed by scanning laser polarimetry of the peripapillary retinal nerve fibre layer (RNFL) thickness at 6 months in the affected eye compared to the unaffected eye at baseline. RNFL in combination with further retinal measures will also be assessed by optical coherence tomography. Secondary outcome measures on brain MRI will include cortical volume, diffusion-weighted imaging, resting state functional MRI, MR spectroscopy and magnetisation transfer ratio. In addition, high and low contrast visual acuity, visual fields, colour vision and electrophysiology will be assessed alongside quality of life measures.

ETHICS AND DISSEMINATION

Ethical approval was given by the south central Oxford B research ethics committee (REC reference: 13/SC/0022). The findings from ACTION will be disseminated through peer-reviewed publications and at scientific conferences.

TRIAL REGISTRATION NUMBER

EudraCT2012-004980-39, ClinicalTrials.gov Identifier: NCT01802489.

Four-Stage Audit Demonstrating Increased Uptake of HIV Testing in Acute Neurology Admissions Using Staged Practical Interventions

Background

UK National Guidelines (UKNG) advise HIV testing in clinically indicated neurological presentations. We audited the impact of our practical strategies to increase uptake of HIV testing at a regional acute neurology admissions unit.

Methods

We audited HIV testing in 4 periods over 2 years: before we designed a UKNG-based “HIV testing in Neurology” protocol (“pre-protocol”); after dissemination of the protocol alone (“post-protocol”); post-protocol dissemination combined with both a tailored departmental admissions clerking proforma to prompt for HIV testing & consenting, and regular focussed tutorials to doctors on HIV testing in neurological patients (“post-proforma”); and finally one year after the post-proforma period (“+1 year”). We also looked at the total number of HIV tests sent from the unit during the two-year period. We assessed significance using Fisher’s exact test.

Results

47.8% of all acute neurology non-stroke admissions were eligible for HIV testing during all the audit periods. Testing rates were as follows: pre-protocol 21.9%; post-protocol 36.6%; post-proforma 83.3%; and at +1 year 65.4% (p<0.05 for both post-protocol and +1 year when compared to pre-protocol). Documentation of consent for HIV testing improved from 25% to 67.6% with the HIV-tailored clerking proforma. The total number of HIV tests requested from the unit doubled in the post-proforma period compared to pre-protocol (p<0.05).

Conclusion

In conclusion: the combination of an HIV testing protocol, a tailored departmental clerking proforma and regular focussed teaching to doctors on indications for HIV testing led to a sustained increase in HIV testing uptake in our regional acute neurology admissions unit.

Optic Neuritis: Another Dickensian Diagnosis

The clinical diagnosis and natural history of optic neuritis was established in the late 1880s by the ophthalmologists von Graefe and Nettleship. The earlier, accurate and insightful description of transient, bilateral visual loss of Esther, the main character in the Charles Dickens novel Bleak House (1852--1853), suggests optic neuritis as a Dickensian diagnosis. Remarkably, Dickens' observations, also preceding the earliest clinical description of multiple sclerosis by Charcot in 1868, described many clinical features such as a prodromal phase; a nadir; gradual recovery over weeks; glare disability; reduced contrast sensitivity; possibly Uhthoff's phenomenon; and visual fading. All this with an accuracy that, to quote Russell Brain, "would credit a trained physician."

Optic neuritis

AIMS

The aim of this study is to provide a clinical update on optic neuritis (ON), its association with multiple sclerosis (MS), and neuromyelitis optica (NMO).

METHODS

This study included a PubMed review of the literature written in the English language.

RESULTS

ON in adults is typically idiopathic or demyelinating, and is characterised by unilateral, subacute, painful loss of vision that is not associated with any systemic or other neurological symptoms. Demyelinating ON is associated with MS, and we review the key studies of ON including the ON treatment trial and several other MS treatment trials and NMO.

CONCLUSION

Acute demyelinating ON can occur in isolation or be associated with MS. Typical ON does not require additional evaluation other than cranial magnetic resonance imaging. NMO is likely a separate disorder from MS and the ON in NMO has a different treatment and prognosis.

METHODOLOGY

The authors conducted an English language search using Pubmed from the years 1964 to 2010 using the search terms 'ON', 'MS' and 'NMO'. The authors included original articles, review articles, and case reports, which revealed new aspects as far as epidemiology, histopathology, clinical manifestations, imaging, genetics, and treatment of ON. Titles were reviewed for topicality and full references were obtained. Letters to the editor, unpublished work, and abstracts were not included in this review.

Clinical characteristics, therapeutic outcomes of isolated atypical optic neuritis in China

BACKGROUND/AIM

The causes of atypical optic neuritis are different from typical demyelinating optic neuritis. It may exist as an isolated entity or may be part of a systemic process. Our aim was to determine the clinical characteristics, and therapeutic outcomes of isolated atypical optic neuritis in China.

METHODS

Inclusion criteria for isolated atypical optic neuritis required fulfillment of at least one of (1)-(3) and both (4), and (5): (1) Visual loss progressing for >2 weeks since onset, (2) No visual recovery over 3 weeks after onset, (3) Worsening of vision over one line of acuity after withdrawal of corticosteroids, (4) No diagnosis of a defined collagen vascular disease or neurological autoimmune disease at onset, and (5) Neuro-ophthalmic follow-up for at least 12 months.

RESULTS

20 cases fulfilled isolated atypical optic neuritis inclusion criteria. 10 cases (50%) were anti-aquaporin-4 antibody positive. 11 of 20 cases (55%) with flare of optic neuritis at the withdrawal of corticosteroids responded poorly to reinitiation of corticosteroid therapy. At the end of follow-up (median 41 month), vision in 60% of involved eyes (18/30 eyes) was still 20/200 or worse.

CONCLUSIONS

In China, isolated atypical optic neuritis has a high incidence of anti-aquaporin-4 antibody and is resistant to corticosteroid therapy.