case_images: PMC11180789_01
case_images: Brain and cervical MRI performed during an acute attack. (A-L) Axial T2-weighted (A-F) and FLAIR (G-L) images of the brain MRI scans showing multifocal patchy or round hyperintense lesions in the superior cerebellar peduncle (A, G), midbrain periaqueduct (B, C, H, I), and left occipital lobe (C, I) and deep white matter in the posterior horn of the right lateral ventricle (D, E, J, K) and bilateral hemioval center (F, L). Sagittal and axial T2-weighted images of cervical MRI scans show longitudinally transverse lesions along the C3-C7 levels (M-O), with heterogeneous patchy enhancement in the gadolinium (Gd)-enhanced MRI (P, Q). The thoracic spinal cord was normal (R). MRI, magnetic resonance imaging; FLAIR, fluid-attenuated inversion recovery; C, cervical.
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case_images: Brain magnetic resonance imaging (MRI) revealed abnormal signals in the tegmentum of the pons and periependymal brainstem lesions ( Supplementary Figure S1 ). T2-weighted and fluid-attenuated inversion recovery (FLAIR) images of a brain MRI scan showed multifocal patchy or round hyperintense lesions in the superior cerebellar peduncle, periaqueduct of the midbrain, left occipital lobe, deep white matter in the posterior horn of the right lateral ventricle, and bilateral centrum semiovale ( Figure 1 ). The sagittal and axial T2-weighted cervical MRI scans showed longitudinal transverse lesions along the C3-C7 levels, with homogeneous patchy enhancement on gadolinium (Gd)-enhanced MRI ( Figure 1 ). The Gd-enhanced MRI showed no enhancement of the brain lesions ( Supplementary Figure S2 ).
case_images: Detection of AQP4- IgG and AGO- IgG by IIF-CBA. Representative CBA photographs show AQP4- IgG in serum (A-C, 1:32 titer) and AGO1, 2- IgG in serum (D-I, 1:100 titer) and CSF (J-L, 1:100 titer). AQP4, neuromyelitis optica spectrum disorder; AGO, argonaute; IIF, indirect immunofluorescence; CBA, cell-based array; CSF, cerebrospinal fluid; GFP, green fluorescent protein; IgG, immunoglobulin G.
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case_images: PMC11180789_01_fimmu-15-1366531-g002.jpg
case_images: f2
case_images: The sagittal and axial T2-weighted cervical MRI scans showed longitudinal transverse lesions along the C3-C7 levels, with homogeneous patchy enhancement on gadolinium (Gd)-enhanced MRI ( Figure 1 ). The Gd-enhanced MRI showed no enhancement of the brain lesions ( Supplementary Figure S2 ). The results showed AQP4-Abs in the blood with a titer of 1:32 ( Figure 2 ); only OCBs were present in the CSF.
case_images: Detection of AGO-IgG by IIF-TBA. IIF of the monkey brain with the patient's serum (A, B) and CSF (C, D) shows strong reactivity with the hippocampal stratum pyramidale and cerebellar granule cells. AGO, argonaute; IIF, indirect immunofluorescence; TBA, tissue-based assay.
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case_images: Therefore, a tissue-based assay (TBA) of the monkey brain with serum and CSF was performed for autoantibody detection, resulting in strong reactivity with the hippocampal stratum pyramidale and cerebellar granule cells ( Figure 3 ).
case_images: Timeline of the patient, with relevant episode and intervention data. IVIG, intravenous immunoglobulin; IVMP, intravenous methylprednisolone; EDSS, expanded disability status scale.
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case_images: The patient's timeline with relevant data on episodes and interventions is presented in  Figure 4 .