Clinical, imaging and follow-up study of optic neuritis associated with myelin oligodendrocyte glycoprotein antibody: a multicentre study of 62 adult patients N. Shor a,b , J. Aboab c , E. Maillart d , A. Lecler b , C. Bensa e , G. Le Guern c , S. Grunbaum f , R. Marignier g , C. Papeix d , E. Heron c , O. Gout e , J. Savatovsky b , D. Galanaud a , C. Vignal h , V. Touitou f and R. Deschamps e a Department of Neuroradiology, Groupe Hospitalier Pitie-Salp^ etriere, AP-HP, Paris; b Department of Neuroradiology, Fondation Ophtalmologique Adolphe de Rothschild, Paris cedex; c Department of Internal Medicine, Centre Hospitalier National d’ophtalmologie des Quinze-Vingts, Paris; d Department of Neurology, Groupe Hospitalier Pitie-Salp^ etriere, AP-HP, Paris; e Department of Neurology, Fondation Ophtalmologique Adolphe de Rothschild, Paris cedex; f Department of Ophthalmology, Groupe Hospitalier Pitie-Salp^ etriere, AP-HP, Paris; g Department of Neurology, H^ opital Neurologique Pierre Wertheimer Hospices Civils de Lyon, Bron; and h Department of Neuro-Ophthalmology, Fondation Ophtalmologique Adolphe de Rothschild, Paris cedex, France Keywords: follow-up, MRI, myelin oligodendrocyte glycoprotein, optic neuritis Received 9 April 2019 revision requested 2 July 2019 Accepted 3 September 2019 European Journal of Neurology 2019, 0: 1–8 doi:10.1111/ene.14089 Abstract Background and purpose: There are few clinico-radiological data on optic neu- ritis (ON) with myelin oligodendrocyte glycoprotein antibody (MOG-IgG). The objective was to characterize the clinico-radiological phenotype and out- come of patients with MOG-IgG-related ON. Methods: The records of all adult patients admitted in three medical centres with MOG-IgG-associated ON who underwent orbital and brain magnetic res- onance imaging (MRI) at the acute phase were reviewed. Spinal cord MRI within 1 month from the ON and all of the follow-up MRI were reviewed. Results: Of 62 patients, 41.9% had bilateral ON and 66.2% optic disc swel- ling. On initial MRI, lesions were anterior (92%), extensive (63%) and associ- ated with optic perineuritis (46.6%). Silent brain lesions were found in 51.8% of patients but were mainly non-specific (81%). Of 39 individuals with spinal MRI at onset, nine had abnormal findings (four were asymptomatic). Two symptomatic patients had longitudinally extensive myelitis with concurrent H- sign. At last follow-up, 5% of patients had visual acuity 0.1. Brain MRI remained unchanged in 41 patients (87%). Conclusions: Our study supports a mostly benign ophthalmological course of MOG-IgG-associated ON, despite initially longitudinally extensive lesions and development of optic nerve atrophy on orbital MRI. Spinal MRI could be of interest in detecting silent suggestive lesions. Introduction Optic neuritis (ON) is a frequent neurological mani- festation of inflammatory central nervous system (CNS) disease, most commonly caused by multiple sclerosis (MS). Recently described [1] myelin oligoden- drocyte glycoprotein antibody (MOG-IgG) associated disease (MOGAD) is the second cause of demyelinating ON and should now be considered. A population-based prospective study included 51 patients referred with a diagnosis of ON, of whom 4% had MOG-IgG [2]. Amongst adult patients, ON is the most common manifestation revealing MOGAD [3]. Only sparse data are available regarding the radio- logical features of MOG-IgG-associated ON. More- over, the populations described often include both paediatric and adult patients [4–6], with different clini- cal phenotypes (ON, myelitis and encephalitis) [3], Correspondence: N. Shor, Department of Neuroradiology, Pitie- Salp^ etriere Hospital, 83 bd de l’H^ opital, 75013 Paris, France (tel.: +33661884335; fax: 0142163515; e-mail: shor.natalia@icloud.com). © 2019 European Academy of Neurology 1 ORIGINALARTICLE EUROPEANJOURNALOFNEUROLOGY