Table 4.

Correct identification of typical clinical syndromes and MRI features for NMOSD.

	N (%)
Although considered a core clinical characteristic for NMOSD, which manifestation is not a cardinal syndrome and would be insufficient to support a diagnosis of NMOSD in an AQP4-IgG-seronegative patient for NMOSD? (Please select all that apply) Optic neuritis (ON) Transverse myelitis (TM) Brainstem syndrome (BSS) Area postrema syndrome (APS) Diencephalic syndrome (DS) Symptomatic cerebral syndrome (SCS) Correct (Brainstem + Diencephalic + Cerebral syndromes) Incomplete (2 out of 3 syndromes) without including ON/TM/APS Incomplete (1 out of 3 syndromes) without including ON/TM/APS Incomplete (2 out of 3 syndromes) including ON/TM/APS Incomplete (1 out of 3 syndromes) including ON/TM/APS	8 (7.5) 9 (8.4) 52 (49.1) 10 (9.4) 57 (53.8) 89 (83.9) 34 (32.1) 26 (24.5) 29 (27.3) 6 (5.6) 3 (2.8)
Which of the following are considered typical clinical presentations of NMOSD or highly suggestive for NMOSD?. Correct answers in bold. Acute unilateral optic neuritis with a poor visual recovery Complete transverse myelopathy with bilateral motor and sensory involvement Double vision due to an internuclear ophthalmoplegia (in a young adult <40 years old) Headache or meningism Facial sensory loss or trigeminal neuralgia (in a young adult <40 years of age) Partial myelopathy Complete gaze palsy or fluctuating ophthalmoparesis Isolated fatigue or asthenia Bilateral optic neuritis or unilateral optic neuritis with a poor visual recovery Subacute cognitive decline Intractable nausea, vomiting, or hiccoughs Lhermitte’s symptom Urge incontinence or erectile dysfunction Hypersomnolence or narcolepsy-like syndrome	82 (77.3) 83 (78.3) 8 (7.5) 0 3 (2.8) 18 (16.9) 6 (5.6) 4 (3.8) 100 (94.3) 3 (2.8) 100 (94.3) 20 (18.8) 35 (33.1) 85 (80.1)
Which of the following regions may be used as additional MRI requirements for NMOSD without AQP4-Ab and NMOSD with unknown AQP4-Ab? (Check all that apply) Long optic nerve lesion(s) Extensive periependymal brain lesions Periventricular Lesions involving the hypothalamus, thalamus Large, confluent subcortical or deep white matter lesion(s) Cortical lesions Lesions involving the dorsal medulla Infratentorial lesions (i.e., middle cerebellar peduncles) Fluffy infratentorial lesions Subcortical Long, diffuse, heterogeneous, or edematous corpus callosum lesions Juxtacortical Spinal cord (i.e., lesions extending over 3 or more complete vertebral segments) Periependymal lesions overlying the fourth ventricle Periventricular lesions extending perpendicularly from ventricles into brain white matter Long lesions in corticospinal tract pathway	97 (91.5) 53 (50) 4 (3.7) 58 (54.7) 25 (23.6) 2 (1.8) 69 (65.1) 15 (14.1) 17 (16.1) 2 (1.8) 20 (18.8) 0 104 (98.1) 72 (67.9) 3 (2.8) 47 (44.3)
To fulfill NMOSD diagnostic criteria, seronegative patients must experience 2 or more different core clinical characteristics (i.e., dissemination in space, affecting different neuroanatomic regions) and other supportive MRI characteristics must also be present False True Not reported	9 (8.4) 95 (89.6) 2 (14)
Acute myelitis with extension into the brainstem can establish DIS (two different neuroanatomic regions)* False True Not reported	10 (47.6) 10 (47.6) 1 (4.8)
In clinical practice, diagnosis of NMOSD is not possible if OC bands are found with a pattern II or III (e.g., in a patient with severe ON and poor recovery + positivity for OCB)* False True Not reported	18 (85.7) 2 (9.5) 1 (4.8)
Which of the following serologic tests would you perform if a phenotype of NMOSD is observed? AQP4-Ab only in serum MOG-Ab only in serum AQP4-Ab and MOG-Ab in serum (at the same time if possible) AQP4-Ab only in CSF MOG-Ab only in CSF AQP4-Ab and MOG-Ab in serum and CSF (at the same time) AQP4-Ab and MOG-Ab in CSF (at the same time)	47 (44.3) 33 (31.1) 68 (64.1) 1 (0.8) 0 16 (15.1) 1 (0.9)
When (optimal timing) would you request AQP4-Ab during the NMOSD diagnosis process (before making a new diagnosis of NMOSD)? (Check all that apply) *responses will be randomly ordered per respondent During an attack After receiving immunosuppressant treatments In remission phase 90 days after completion of treatment if PLEX or IVMP was received Before receiving immunosuppressant treatments After 3–6 months if initial AQP4-Ab were negative, but high suspicion of NMOSD exists. Before 30 days if PLEX or IVMP was received	66 (62.2) 1 (0.9) 9 (8.4) 38 (35.8) 68 (64.1) 63 (59.4) 7 (6.6)
What is the optimal method for testing AQP4-IgG to maximize sensitivity and specificity? Tissue-based IIF Live cell-based assay ELISA Fixed cell-based assay Flow cytometry Not reported	5 (4.7) 60 (56.6) 5 (4.7) 6 (4.9) 5 (5.6) 25 (23.5)

*These questions were only answered by neurologists from Brazil (N = 21; survey in English). Missing data from the Spanish survey were found only for these questions.

Correct answers are shown in bold.