Myelitis. Myelitis. Multiple Sclerosis (MS) Acute demyelinating syndrome (ADS) Indictions for spinal cord MRI in MS.

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1 Myelitis Myelitis Majda M Thurnher Professor of Radiology Medical University of Vienna University Hospital Vienna Department of Biomedical Imaging and Image-Guided Therapy Vienna Austria Acute demyelinating syndrome Multiple sclerosis (MS) Acute disseminated encephalomyelitis (ADEM) Transverse myelitis (TM) Neuromyelitis optica (NMO) Sarcoidosis Vasculitis Paraneoplastic myelopathy Infectious myelitis Past President of the European Society of Neuroradiology (ESNR) Acute demyelinating syndrome (ADS) Optic neuritis (ON) Transverse myelitis (TM) Clinically isolated syndromes (CIS) Acute disseminated encephalomyelitis (ADEM) Neuro-myelitis optica spectrum disorder (NMOSD) Multiphasic ADEM (MDEM) Multiple sclerosis (MS) Progressive neurodegenerative disorder d Multiple inflammatory demyelinating foci called PLAQUES Spinal cord involvement: - focal lesions - diffuse abnormalities - spinal cord atrophy Multiple Sclerosis (MS) Identification and distinction of different subtypes of ADS can be challenging, especially at the initial episode with important implications with regard to treatment and prognosis. Indictions for spinal cord MRI in MS Adding spinal cord to brain MR imaging in the routine follow-up of RR-MS patients, reveals a significant proportion of disease activity otherwise neglected Focal MS Lesions < 2 segments (short segment) wedge / round shaped lesions lateral and posterior columns (may be ventral) high signal on T2WI Iso on T1WI New spinal cord lesions independently identify patients with a high risk of disability progression Rovira A, de Stefano N. Curr Opin Neurol 2016

2 Enhancement Only a small percentage of spinal cord lesions show contrast enhancement, and those that do are commonly associated with new clinical symptoms. Diffuse Abnormalities Spinal Cord Atrophy More common in PPMS and SPMS Extensive and confluent changes PPMS cases with diffuse SI abnormalities throughout the cord Progressive MS forms Strong impact on clinical disability Progresses faster over time than brain volume loss Cord atrophy is now being considered as an outcome measure in clinical trials that assess the efficacy of neuroprotective agents Courtesy of Sundgren P/SE Bieniek M J Neurol Neurosurg Psych 2006 Rovira A Semin Ultrasound CT MRI 2016

3 Standardized protocol for spinal cord MRI Acute Disseminated Encephalomyelitis (ADEM) An immune-mediated demyelinating disorder of the CNS Children Within 3 weeks of infection, vaccination or drugs Proton density (PD) and T2WI SE sequences with a spatial resolution of at least 3x1x1 mm are essential Heavily T1-weighted sequences, such as PSIR (phase-sensitive inversion recovery) or MP2RAGE STIR should be considered as a complementary sequence, but cannot be used in isolation due to its low specificity Rovira A, de Stefano N. Curr Opin Neurol % spinal cord involvement Perivenular mononuclear infiltration & microglial reaction Patient #1 Patient #2 Initial 6 months follow-up Anti myelin oligodendrocyte glycoprotein (MOG) MOG is a minor myelin protein and expressed on the surface of CNS myelin sheaths MOG belongs to the immunoglobulin superfamily and is believed to play a role as surface receptor or cell adhesion molecule Antibodies of the IgG1 subclass against MOG have been found in ADEM and other demyelinating disorders Anti-MOG autoantibodies MOG antibodies are present in 1/3 of all children with an acute demyelinating syndrome (ADS) MOG-abs can be found in TM, ON, NMOSD and MDEM In MOG-ab-positive ADS, the optic nerves and myelon are frequently affected MOG-ab titers will subsequently decline in ADEM Subgroup of children with high and persisting MOG-ab titers has recurrent episodes associated with a less favorable outcome Hennes EM Neuropediatrics 2017

4 Transverse myelitis (TM) Transverse myelitis is defined as the development of an inflammatory spinal cord syndrome with a nadir between 4h and 21 days following the onset of symptoms Longitudinally extensive transverse myelitis (LETM) is generally taken to mean myelitis which extends over a continuous lesion which is at least 3 vertebral segments in length NMO, infarction, paraneoplastic, ADEM The etiology remains unknown in a substantial portion of cases, which are classified as idiopathic. TM diagnostic criteria ITM diagnostic criteria were published 15 years ago They are based on timing of clinical onset and progression to nadir, CSF abnormalities, and MRI features of gadolinium enhancement Neuromyelitis Optica (NMO) NMO is considered to be an autoimmune antibody-mediated disease, induced by a specific serum autoantibody, the NMO- IgG, directed against Aquaporin-4 Revisions to the ITM criteria reflecting recent advances in neuroimaging and specific biomarkers are indicated. Aquaporin-4 (AQP) is the most abundant water channel protein in the CNS, mainly expressed on astrocytic foot processes at the BBB, subpial and subependymal regions Zalewski NL Neurology 2018 Lennon VA Lancet 2004

5 Diagnostic criteria of NMO Neuromyelitis Optica (NMO) The proportion of cases with a non-caucasian background is significantly greater (Asians) Female : male ratio is 9:1 The median age at onset of NMO is the late 30s NMO cases in childhood and in the elderly Kim W J Clin Neurol 2011 Neuromyelitis Optica (NMO) Extensive demyelination of the white and gray matter of the spinal cord Optic nerve involvement in NMO Optic neuritis precedes or is simultaneous with myelitis Usually severe, painful Unilateral or bilateral Selective involvement of chiasm is possible Longer than half of the ON length Optic neuritis (ON) Brain lesions c/o Andrea Rossi Optic nerve involvement in NMO Spinal cord involvement in NMO Acute ON - Nonspecific optic nerve sheath thickening - Optic nerve hyperintensities T2wi - Gadolinium enhancement on postcontrast T1WI in acute ON Chronic ON - Long segmental atrophy - STIR hyperintense Longitudinally extensive TM (LETM) At least 3 vertebral segments Edematous in acute stage Centrally located, often H-shaped 33% - 71% enhance Lesion may fragment with new attack Later: focal atrophy MORE POSTERIOR involvement!!! Courtesy of Rossi A/IT

6 April 2005 May 2005 July 2005 Courtesy of Castillo M/US Courtesy of Rossi A/IT Bright spotty lesions (BSL) Courtesy of Rossi A/IT Yonezu T Mult Scler 2013 BSL seen on axial T2 is a discriminative factor for NMO AQP4 + vs. AQP4 - Chee CG AJNR Am J Neuroradiol 2018

7 Enhancement in NMO shaggy ring enhancement Will be present in 30% of NMOSD cases The presence of ring-enhancement distinguished NMOSD from other causes of LETM but on its own did not distinguish NMOSD from MS. Spinal cord atrophy in NMO Brain involvement in NMO Nonspecific supratentorial WM lesions Diencephalic lesions surrounding third ventricles and cerebral aqueduct Dorsal brainstem lesions adjacent to the fourth ventricle Corticospinal tract lesions Hemispheric white matter lesions Lesions surrounding lateral ventricles Akaishi Neuroimag Clin N Am 2017 Diencephalic lesions surrounding third ventricles and cerebral aqueduct Dorsal brainstem lesions adjacent to fourth ventricle This area, the emetic reflex center, has a less restrictive blood-brain barrier, making it more accessible to AQP4-IgG attack Kim JE et al. Journal of Neurological Sciences 2011 Tackley Mult Scler 2014 intractable hiccups nausea vomiting

8 Lesions surrounding the lateral ventricles located immediately next to the lateral ventricles, following the ependymal lining marbled pattern arch bridge pattern Lesions involving corticospinal tracts Unilateral or bilateral Kim JE Journal of Neurological Sciences 2011 Nakmura M et al. Multiple Sclerosis 2009 Kim HJ et al. Neurology 2015 Periependymal brain lesions Hemispheric lesions Wingerchuk DM Neurology 2015 Lotze Pediatrics 2008 anti-aqp4 + vs. anti-mog+ Spinal cord Neurosarcoidosis AQP4 The most common is acute myelitis Involvement of chiasm LETM with swelling Cord atrophy MOG The most common is ON Involvement of both ON LETM or short myelitis with no swelling No cord atrophy Spinal cord involvement occurs in up to 25% of patients with neuroscarcoidosis Isolated spinal neurosarcoidosis is extremely rare - Leptomeningeal enhancement - Fusiform spinal cord enlargement - Focal or diffuse intramedullary disease - Spinal cord atrophy Brain lesions Brain lesions Poor prognosis Better prognosis Enhancement Central enhancement alone (11%) Central enhancement in combination with dorsalsubpial enhancement (89%) often resembling a trident head on axial sequence Akaishi Neuroimag Clin N Am 2017

9 Focal enhancing lesions are associated with recent neurologic impairment and respond to corticosteroid treatment Central canal enhancement and the trident sign in spinal cord sarcoidosis CNS Vasculitis Brain and spinal cord may be involved by an array of systemic vasculitides which include Systemic lupus erythematosus (SLE) Wegener s granulomatosis Polyarteritis nodosa Churg Strauss angiitis Behçets syndrome Sjögren s syndrome - Enlargement of the cord - T2-hyperintense focal lesions - Leptomeningeal Enhancement! Zalewski NL Neurology 2016 Headache, fever, hyperalgesia, Numbness of the left side of the body Pain in the limbs (during night) Abducens nerve palsy CSF analysis: 52/3 cells

10 Myelopathy in Beçhet s disease: a Bagel Sign Paraneoplastic Myelopathy Bagel Sign pattern: A central lesion with hypointense core and hyperintense rim with or without contrast enhancement MotorNeuron pattern: a symmetric involvement of the anterior horn cells Long myelitis Enhancing May precede a cancer diagnosis Tract-specific myelopathy (corticospinal tract) Uygunoglu U Ann Neurol 2017 Infectious Myelitis Imaging depends on type of infection Cord enlargement & abnormal signal Enhancement (focal or ring-like) Other organs involved (brain) Galassi G Acta Neurol Belg 2015 Herpes Zoster Virus (HZV) Myelitis Tuberculosis Courtesy of Castillo M/USA

11 Pyogenic spinal cord abscess Noccardiosis Courtesy of Macedo L/BR Courtesy of Castillo M/USA Cysticercosis Candida 10-year-old boy, immunosuppressed due to CML & BMT Courtesy of Castillo M/USA CASE 60-year-old female Acute myeloic leukemia (AML) Allogenic stem cell transplantation Chagas disease American trypanosomiasis

12 GVHD with IMDD Focal Enhancement in Myelopathy Allogeneic hemopoietic stem cell transplant (HSCT) Neurologic complication occur in 14-42% of patients: PRES, seizures, encephalopathy, infections Rarely graft versus host disease (GVHD) MS HSV Nocardia Immune-mediated demyelinating disease (IMDD) - optic neuritis - myelitis - acute demyelinating polyneuropathy - ADEM Metastasis Lymphoma Enhancement pattern Trident sign Sarcoidosis Bright spotty lesion NMO Bagel sign Bechet s disease NMO MS Sarcoidosis Astrocytoma

13 Tuberculosis Toxoplasmosis Cysticercosis Nocardiosis