Bilateral Internuclear Ophthalmoplegia in a Patient with Devic's Neuromyelitis Optica

Internuclear Ophthalmoplegia Characterizes Multiple Sclerosis Rather Than Neuromyelitis Optica Spectrum Disease

BACKGROUND

Neuromyelitis optica spectrum disease (NMOSD) and multiple sclerosis (MS) share clinical presentations including optic neuritis and brainstem syndromes. Internuclear ophthalmoplegia (INO) is characterized by slowed ipsilateral adduction saccades and results from a lesion in the medial longitudinal fasciculus (MLF). Although INO is a common clinical finding in MS, its prevalence in NMOSD is unknown. The objective of this work is to determine the comparative frequencies of INO in patients with NMOSD and MS and compare clinical features of both disease processes.

METHODS

This is a retrospective study of patients 18 years and older who have an established diagnosis of NMOSD or MS and were evaluated by both neuro-ophthalmology and neuro-immunology specialists between 2014 and 2020. Electronic medical records were screened for documentation of an acute INO at any time during follow-up. Incidence rates were calculated from number of cases of new-onset INO and patient years observed. Logistic regression was used to evaluate the likelihood of developing an INO at any time point for NMOSD vs MS patients. Multivariable analysis was performed by adjusting for age, race, gender, and length of follow-up.

RESULTS

Two hundred eighty patients (80 NMOSD, 200 MS) were included. Age range was 18-79 years with a mean age of 35.14 (SD ± 12.41 years). Average length of follow-up in MS and NMOSD patients was 4.18 years vs 3.79 years, respectively (P > 0.05), and disease duration before the start of the study in MS and NMOSD was 8.76 years vs 4.65 years, respectively (P < 0.01). Mean disease duration and follow-up time of both groups was 7.58 years and 4.07 ± 2.51 years, respectively. NMOSD patients were predominantly seropositive for AQP4 antibody (61.25%, n = 49). Individuals who had MOG antibody but also met NMOSD criteria were also included (18.75%, n = 15). The frequency of INO at any time point was 1.25% (n = 1) in NMOSD compared with 16% (n = 32) in MS. The incidence rate of new-onset INO in NMOSD (excluding MOGAD) was 3.8/1,000 person years and 23.9/1,000 person years in MS. Adjusted analysis showed that NMOSD patients were 13.89 times (odds ratio [OR] 0.07, 95% confidence interval [CI] 0.01-0.598, P = 0.015) less likely to develop an INO compared with those with MS when including MOGAD patients, 12.5 times less likely (OR 0.08, 95% CI: 0.10-0.67, P = 0.02) when excluding MOGAD patients and 9.62 times less likely (OR 0.10, 95% CI: 0.01-0.87, P = 0.036) for AQP4+ patients.

CONCLUSIONS

Our study shows that the incidence of new INO (3.8 vs 23.9 per 1,000 person years), and the odds of having INO at any time point are significantly lower in NMOSD than MS. This suggests that INO and consequently MLF lesions are less common in NMOSD. The presence of an INO may help in the differentiation of NMOSD from MS and may aid in earlier implementation of disease appropriate therapy.

Ophthalmic manifestations of myelin oligodendrocyte glycoprotein-IgG-associated disorder other than optic neuritis: a systematic review

Background/Aims

Optic neuritis (ON) is the primary ophthalmic manifestation of myelin oligodendrocyte glycoprotein-IgG-associated disorder (MOGAD), but numerous reports have expanded the visual manifestations of this condition. The goal of this study was to synthesise the extensive literature on this topic to help ophthalmologists understand when testing for MOG-IgG should be considered.

Method

A systematic review of the English-language literature was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and searches were conducted using Ovid MEDLINE (from January 1, 1948 to April 1, 2020) and Ovid EMBASE (from January 1, 1947 to April 1, 2020). Inclusion criteria included studies describing non-isolated ON ophthalmic manifestations where cell-based assays were used for the detection of MOG antibodies.

Results

Fifty-one articles representing 62 patients with a median age of 32.0 (range 2–65), female gender (51%) and follow-up of 20.0 months (range: 1–240) were included. Twenty-nine patients had non-isolated ON afferent visual manifestations: uveitis, peripheral ulcerative keratitis, acute macular neuroretinopathy, neuroretinitis, venous stasis retinopathy, large preretinal macular haemorrhage, orbital inflammatory syndrome, orbital apex syndrome, optic perineuritis, papilloedema and homonymous visual field defects. Incomplete recovery of ON was associated with a case of Leber’s hereditary optic neuropathy. Efferent ophthalmic manifestations included cranial neuropathies, internuclear ophthalmoplegia, central nystagmus, saccadic intrusions and ocular flutter. Cranial nerve involvement was secondary to enhancement of the cisternal portion or brainstem involvement. All included cases were treated with corticosteroids with 31% of cases requiring additional immunosuppressive therapy.

Conclusions

MOGAD has been associated with various afferent and efferent ophthalmic manifestations apart from isolated ON. Awareness of these findings may result in earlier diagnosis and treatment.

Eye movement abnormalities in AQP4-IgG positive neuromyelitis optica spectrum disorder

BACKGROUND AND PURPOSE

Neuromyelitis optica spectrum disorder (NMOSD) has been recognized as a disease characterized by severe visual afferent impairment. Abnormal eye movements, as the other important neuro-ophthalmic manifestation of NMOSD, were commonly overlooked. The aim of our study was to describe the ocular motor manifestations of AQP4-IgG positive NMOSD patients, and explore the value of eye movement abnormalities in the evaluation of the disabled disease.

METHODS

Systemic clinical bedside ocular motor examinations and quantitative horizontal saccadic eye movement assessments were performed in 90 patients with AQP4-IgG positive NMOSD. General disability was evaluated by expanded disability status scale (EDSS). Vision-specific functional status was evaluated by the National Eye Institute-Visual Function Questionnaire (NEI-VFQ 25) and the 10-item neuro-ophthalmic supplement. Brain magnetic resonance imaging (MRI) was acquired in all patients.

RESULTS

In clinical examination, eye movement abnormalities were found in 38% of NMOSD patients. Abnormalities in the quantitative saccadic test were found in 67% of NMOSD patients, including 48% of patients with clinically normal eye movements. EDSS scores in patients with clinical eye movement abnormality were significantly higher (P<0.001) than those with a normal examination. The 10-item neuro-ophthalmic supplement score was significantly associated with quantitative saccadic eye movement abnormalities (P=0.031).

CONCLUSIONS

Eye movement abnormalities were common in AQP4-IgG positive NMOSD patients, and were associated with general disability and specific visual handicap. The systemic clinical eye movement examination combined with the quantitative saccade test was easy to perform, and could provide additional useful information in evaluating NMOSD.

A Case of Neuromyelitis Optica Masquerading as Miller Fisher Syndrome

A 22-year-old woman presented with double vision that she had experienced since an infection 2 weeks previously. A neurological examination showed limited bilateral eye abduction, mimicking Miller Fisher syndrome. However, T2-weighted magnetic resonance imaging of her brain revealed hyperintense areas in the tegmentum of the pons, including the abducens nucleus, and her serum anti-aquaporin-4 antibody test was positive. She was finally diagnosed with neuromyelitis optica. Intravenous high-dose steroid therapy immediately improved the patient's abduction palsy, but bilateral optic neuritis manifested during the treatment. Subsequent treatment with plasma exchange improved her optic neuritis symptoms.