A comparison between spinal cord infarction and neuromyelitis optica spectrum disorders: Clinical and MRI studies

Relevance of bright spotty lesions in neuromyelitis optica spectrum disorders (NMOSD): a case series

Background

Neuromyelitis optica (NMO), or neuromyelitis optica spectrum disorder (NMOSD), is an autoimmune CNS condition which often has a complex clinical course. Longitudinally extensive transverse myelitis (LETM) is an important and sensitive MRI finding but is not very specific to NMOSD and is seen in other causes of myelitis.

Case presentations

We report 11 NMO cases, all seen in women from 25 to 75 years at the time of diagnosis, with most above 65 years of age. All patients were seropositive for AQP4–IgG antibodies, and none had anti-MOG antibodies. Clinical presentations were diverse, the most common being paralytic and visual changes. In this study, 5 of the 11 seropositive NMO patients (45%) had bright spotty lesion (BSLs) on their MRI spine, as opposed to none (0%) in the control group. BSLs were defined as hyperintense foci of signal abnormality on T2-weighted images compared to the surrounding CSF. Treatment included symptomatic management and immunotherapy; timely management led to improvement in all the cases, with partial recovery seen in most (91%) and complete recovery seen only in one.

Conclusions

BSLs are a newly defined spinal MRI finding with high specificity, but low sensitivity for NMOSD. The absence of BSLs in the control group establishes its prolific role in distinguishing NMO from MS, ITM, MOGAD and other forms of myelitis. The main aim of this retrospective case–control study was to determine the diagnostic importance and specificity of bright spotty lesions (BSLs) in NMOSD and its ability to discriminate NMOSD from other causes of LETM.

The utility of diffusion-weighted imaging in patients with spinal cord infarction: difference from the findings of neuromyelitis optica spectrum disorder

Background

Magnetic resonance imaging (MRI) plays a crucial role in diagnosing spinal cord infarction (SCI). However, the findings are often indistinguishable from those of other intramedullary diseases, such as neuromyelitis optica spectrum disorder (NMOSD). Although diffusion-weighted imaging (DWI) is a promising technique, the utility for discriminating SCI from NMOSD remains unclear because the DWI findings of acute NMOSD lesions have not been investigated in detail.

Methods

Clinical and MRI findings were retrospectively evaluated in 15 and 12 patients with acute SCI and NMOSD, respectively. First, clinical characteristics were compared between the SCI and NMOSD groups. Second, MRI abnormalities were examined to find differences between these groups. Third, in the SCI group, factors influencing T2 and DWI abnormalities were analyzed using the mixed-effects logistic regression analysis.

Results

The proportion of female patients was higher in the NMOSD group (92%) than in the SCI (40%). The time from symptom onset to nadir was smaller in the SCI group (median [interquartile range]; 4 [0.1–8.3] hours) than in the NMOSD (252 [162–576]). On T2-weighted images, SCI lesions had smaller length than NMOSD (2 [1–2] and 5 [2–7] vertebral segments, respectively). Focal lesions within the T9–L2 level were found only in patients with SCI. DWI hyperintensity was observed both in the SCI (frequency, 100%) and NMOSD (60%) groups. On apparent diffusion coefficient (ADC) maps, the hyperintensities of SCI had corresponding hypointensities, whereas those of NMOSD were isointense and a large portion of NMOSD lesions had hyperintense signals. Owl’s eyes sign and pencil-like hyperintensity, typically reported as T2 findings suggestive of SCI, were also found on DWI. Posterior linear hyperintensity was frequently detected on DWI in patients with posterior spinal artery infarction. The presence of MRI abnormality revealing SCI was modeled with the time from symptom onset, imaging sequence and plane, and affected vascular territory.

Conclusions

DWI and ADC maps help distinguish SCI from NMOSD. The time from symptom onset, imaging sequence, and imaging plane should be considered when MRI findings are interpreted in patients with suspected SCI.

Magnetic Resonance Image in Monitor and Diagnosis of Patients with Neuromyelitis Optica

This study was aimed to investigate the craniocerebral magnetic resonance imaging (MRI) measurement and clinical characteristics of patients with neuromyelitis optica (NMO) and multiple sclerosis (MS). 50 patients with NMO (NMO group) and 50 patients with MS (MS group) were studied. The clinical manifestations, brain injury morphology, MRI signal characteristics, brain distribution characteristics, and related laboratory tests (serum aquaporin 4 [AQP4] antibody) were statistically analyzed. The results showed that the analysis of clinical manifestations of patients revealed that optic neuritis (37 cases) was the most common disease in NMO patients, and myelitis (16 cases) was more common in MS patients than NMO patients. There were significant differences in gender ratio, abnormal expression of brain MR1, positive serum AQP4-IgG, and other immune diseases and symptoms between the two groups (P < 0.05). When the lesions measured by MRI were located in the white matter area of the cerebral hemisphere, the image showed blurred edges and a relatively symmetrical distribution. When the lesions measured by MRI were located around the medulla oblongata, the lesions mainly involved the central gray matter and white matter of the spinal cord, with patchy and line-like long T1 and long T2 signals. Moreover, in the late stage of recurrence of spinal cord disease, severe spinal cord atrophy may occur. In conclusion, craniocerebral MRI measurement in NMO patients can provide more basis for the diagnosis and differential diagnosis of the disease, so as to improve the diagnostic level of NMO.

Correlations among disability, anti-AQP4 antibody status and prognosis in the spinal cord involved patients with NMOSD

Background

Neuromyelitis optica spectrum disorder (NMOSD) is a rare neuroinflammatory disorder of the central nervous system that typically involves the optic nerve, the spinal cord and other specific brain regions. In relapse of the disease, factors associated with clinical features and lesion severity are important for clinicians to predict disease-related disability.

Methods

We retrospectively analyzed 22 female patients with NMOSD who had spinal cord lesions. Detailed clinical features, onset symptoms, motor disability, relapse episodes, serum aquaporin-4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) autoantibodies and MRI characteristics were documented to correlate their associations with the nadir and three-month Expanded Disability Status Scale (EDSS) scores. Patients with three-month EDSS scores below four (< 4) were categorized as the good outcome group, while those with scores of four or more (> 4) were categorized as the poor outcome group.

Results

In patients with NMOSD, the mean age was 44.5 ± 12.8 years, and the mean three-month EDSS score was 4.3 ± 1.9. A significantly higher all-limb muscle power score was found in the good EDSS group than in the poor EDSS group (p = 0.01). A tendency toward longer follow-up periods and lower anti-AQP4 antibody levels was found in the good outcome group. Serum anti-AQP4 antibodies were present in 86% of patients with NMOSD, and MOG autoantibodies were found in one anti-AQP4 antibody-negative patient (33.3%). In patients with NMOSD, more than 40% of spinal cord lesions were distributed at the middle cervical and upper thoracic levels.

Conclusions

Our findings suggest that EDSS scores and MRC scores at the nadir had significant associations with three-month EDSS scores. The topographic distributions of the spinal cord lesions might relate to different serum anti-AQP4 antibody status. However, further studies will be needed to corroborate this finding.

Imaging highlights of anterior spinal cord infarction: Owl's eye sign

The article's abstract is not available.  

Cervical spinal cord infarction associated with coronavirus infectious disease (COVID)-19

Coronavirus disease (COVID-19) has a number of emerging neurological manifestations in addition to pneumonia and respiratory distress. In what follows, we describe a case of a previously healthy young man with severe COVID-19 who subsequently developed an acute flaccid paralysis. Work up revealed a lesion in his cervical spinal cord concerning for spinal infarction or transverse myelitis. He received empiric pulsed steroids without improvement. Taken together, we felt his presentation was most consistent with spinal cord infarction in the setting of critical illness with COVID-19. We believe this is a rare case of spinal cord stroke associated with COVID-19.

Bright spotty lesions as an imaging marker for neuromyelitis optica spectrum disorder

Neuromyelitis optica spectrum disorder (NMOSD) is a rare inflammatory demyelinating disorder of the central nervous system (CNS). Aquaporin-4 (AQP4) antibodies in the serum are highly specific for the diagnosis of NMOSD, but the sensitivity remains under 90% allowing for diagnosis of AQP4 IgG seronegative disease. It remains of crucial importance to identify seronegative NMOSD myelitis as early as the first attack to initiate long-term treatment that will reduce future relapses and disability and to avoid potentially harmful treatments such as those of multiple sclerosis (MS). Over the years, many spinal imaging features have been reported to favour the diagnosis of NMOSD, but only longitudinally extensive transverse myelitis (LETM) was specific enough to make the diagnostic criteria in the AQP4 IgG seronegative cases. Bright spotty lesions (BSLs), which are defined as hyperintense lesions on axial T2-weighted images and sometimes associated with T1 low signal, are now reported to have a higher specificity and sensitivity compared to LETM in predicting a diagnosis of NMOSD against other causes of myelitis. In the review, we aim to highlight the position of BSLs in diagnosing NMOSD as well as its possible role as a prognostic factor for the clinical outcome.

[A case of spinal cord infarction accompanied with neuromyelitis optica spectrum pathophysiology]

We report a 60-year-old woman who developed spinal cord infarction (SCI) with anti-aquaporin (AQP) 4 antibody seropositive. She was admitted to our hospital with acute onset of flaccid paraparesis and urinary disturbances that completed within a few minutes after acute pain in her lower back. Neurological examination revealed flaccid paraparesis, bladder and bowel dysfunction and dissociated sensory loss below the level of Th11 spinal cord segment. Diffusion weighted imaging (DWI) and T₂-wighted imaging (T₂WI) of thoracic spine MRI showed high signal intensity in the spinal cord between Th9 and Th12 vertebral levels with decreased apparent diffusion coefficient (ADC). We diagnosed her as having SCI. Thereafter the serum examination on admission was reported as positive for anti-aquaporin 4 (AQP4) antibody. Cerebrospinal fluid (CSF) analysis revealed pleocytosis, and the spinal cord lesions became enlarged in MRI on 12 days after the onset. We, therefore, suspected that the pathophysiology of neuromyelitis optica spectrum disorder (NMOSD) accompanied SCI. The patient underwent two courses of high dose intravenous methylprednisolone (IVMP) for three days (1 g/day). Her neurological symptoms did not improve significantly, but the size of T₂WI MRI high signal lesion improved to that of the initial MRI scan. Anti-AQP4 antibody seropositivity may have modified the SCI pathology in the present patient.

Serum Neurofilament to Magnetic Resonance Imaging Lesion Area Ratio Differentiates Spinal Cord Infarction From Acute Myelitis

BACKGROUND AND PURPOSE

The diagnosis of spontaneous spinal cord infarction (SCI) is limited by the lack of diagnostic biomarkers and MRI features that often overlap with those of other myelopathies, especially acute myelitis. We investigated whether the ratio between serum neurofilament light chain levels and MRI T2-lesion area (neurofilament light chain/area ratio-NAR) differentiates SCI from acute myelitis of similar severity.

METHODS

We retrospectively identified Mayo Clinic patients (January 1, 2000-December 31, 2019) with (1) SCI, (2) AQP4 (aquaporin 4)-IgG or MOG (myelin oligodendrocyte glycoprotein)-IgG-associated myelitis at disease clinical presentation, or (3) idiopathic transverse myelitis from a previously identified population-based cohort of patients seronegative for AQP4-IgG and MOG-IgG. Serum neurofilament light chain levels (pg/mL) were assessed at the Verona University (SIMOA, Quanterix) in a blinded fashion on available stored samples obtained ≤3 months from myelopathy presentation. For each patient, the largest spinal cord lesion area (mm²) was manually outlined by 2 independent raters on sagittal T2-weighted MRI images, and the mean value was used to determine NAR (pg/[mL·mm²]).

RESULTS

Forty-eight patients were included SCI, 20 (definite, 11; probable, 6; possible, 3); acute myelitis, 28 (AQP4-IgG-associated, 17; MOG-IgG-associated, 5; idiopathic transverse myelitis, 6). The median expanded disability status scale score (range) at myelopathy nadir were 7.75 (2-8.5) and 5.5 (2-8), respectively. Serum neurofilament light chain levels (median [range] pg/mL) in patients with SCI (188 [14.3-2793.4]) were significantly higher compared with patients with AQP4-IgG-associated myelitis (37 [0.8-6942.9]), MOG-IgG-associated myelitis (45.8 [4-283.8]), and idiopathic transverse myelitis (15.6 [0.9-217.8]); P=0.01. NAR showed the highest accuracy for identification of SCI versus acute myelitis with values ≥0.35 pg/(mL·mm²) yielding 86% specificity and 95% sensitivity (area under the curve=0.93). The positive and negative likelihood ratios were 6.67 and 0.06, respectively. NAR remained independently associated with SCI after adjusting for age, gender, immunotherapy before sampling, and days from myelopathy symptoms onset to sampling (P=0.0007).

CONCLUSIONS

NAR is a novel and promising clinical biomarker for differentiation of SCI from acute myelitis.

Spinal Cord Infarction: A Single Center Experience and the Usefulness of Evoked Potential as an Early Diagnostic Tool

Background: Spinal cord infarction (SCI) is a rare disease and its early diagnosis is challenging. Here, we described the clinical features and imaging findings of SCI, and assessed the results of evoked potential (EP) studies to elucidate their diagnostic role in the early stage of SCI.

Methods: We retrospectively analyzed 14 patients who had spontaneous SCI. The demographic, neurological, and temporal profiles of the SCI patients were identified. We reviewed the imaging findings and assessed the changes in them over time. To review EP, central motor conduction time (CMCT) and somatosensory evoked potential (SEP) values were obtained. We also enrolled 15 patients with transverse myelitis (TM), and compared the clinical, radiological and electrophysiological features between SCI and TM patients.

Results: The ages of the SCI patients ranged from 54 to 73 years. Nine patients (64.3%) showed nadir deficits within 6 h. The most common type of clinical visit was via the emergency center. Nine patients (64.3%) presented with peri-onset focal pain. The median initial modified Rankin scale score was 3. For 9 patients (64.3%), initial T2 imaging findings were negative, but subsequent diffusion weighed imaging (DWI) showed diffusion restriction. Vertebral body infarction was observed in 5 patients (35.7%). EP data were available for 10 SCI patients. All 8 patients who had their CMCT measured showed abnormalities. Among them, motor evoked potentials were not evoked in 6 patients at all. SEP was measured in 10 patients, and 9 of them showed abnormalities; one of them showed no SEP response. For 5 patients, the EP studies were done prior to DWI, and all the patients showed definite abnormalities. The abnormalities in the EP findings of the SCI patients were more profound than those of the TM patients, even though the duration from the onset to the start of the study was much shorter for SCI patients.

Conclusion: SCI can be diagnosed based on typical clinical manifestations and appropriate imaging studies. Our study also indicates that immediate sensory and motor EP study can have an adjuvant diagnostic role in the hyperacute stage of SCI, and can improve the accuracy of diagnosis.

Hyperacute extensive spinal cord infarction and negative spine magnetic resonance imaging: a case report and review of the literature

RATIONALE

Spinal cord infarction (SCI) accounts for only 1% to 2% of all ischemic strokes and 5% to 8% of acute myelopathies. Magnetic resonance imaging (MRI) holds a role in ruling out non-ischemic etiologies, but the diagnostic accuracy of this procedure may be low in confirming the diagnosis, even when extensive cord lesions are present. Indeed, T2 changes on MRI can develop over hours to days, thus accounting for the low sensitivity in the hyperacute setting (ie, within 6 hours from symptom onset). For these reasons, SCI remains a clinical diagnosis. Despite extensive diagnostic work-up, up to 20% to 40% of SCI cases are classified as cryptogenic. Here, we describe a case of cryptogenic longitudinally extensive transverse myelopathy due to SCI, with negative MRI and diffusion-weighted imaging at 9 hours after symptom onset.

PATIENT CONCERNS

A 51-year-old woman presented to our Emergency Department with acute severe abdominal pain, nausea, vomiting, sudden-onset of bilateral leg weakness with diffuse sensory loss, and paresthesias on the trunk and legs.

DIAGNOSES

On neurological examination, she showed severe paraparesis and a D6 sensory level. A 3T spinal cord MRI with gadolinium performed at 9 hours after symptom onset did not detect spinal cord alterations. Due to the persistence of a clinical picture suggestive of an acute myelopathy, a 3T MRI of the spine was repeated after 72 hours showing a hyperintense "pencil-like" signal mainly involving the grey matter from T1 to T6 on T2 sequence, mildly hypointense on T1 and with restricted diffusion.

INTERVENTIONS

The patient was given salicylic acid (100 mg/d), prophylactic low-molecular-weight heparin, and began neuromotor rehabilitation.

OUTCOMES

Two months later, a follow-up neurological examination revealed a severe spastic paraparesis, no evident sensory level, and poor sphincteric control with distended bladder.

LESSONS

Regardless of its relatively low frequency in the general population, SCI should be suspected in every patient presenting with acute and progressive myelopathic symptoms, even in the absence of vascular risk factors. Thus, a clinical presentation consistent with a potential vascular syndrome involving the spinal cord overrides an initially negative MRI and should not delay timely and appropriate management.

Different magnetic resonance imaging features between MOG antibody- and AQP4 antibody-mediated disease: A Chinese cohort study

Few studies have compared radiological features obtained on magnetic resonance imaging (MRI) between myelin oligodendrocyte glycoprotein antibody (MOG-ab)- and aquaporin 4 antibody (AQP4-ab)-positive patients. In this study, 77 MOG-ab and 92 AQP4-ab patients were enrolled. The results demonstrated that the brain MRI-based incidence of subcortical white matter lesions was higher in MOG-ab patients (p < .000) than in AQP4-ab patients and that the former therefore had a higher incidence of periventricular lesions (p = .003). The posterior limb of the internal capsule was more prone to lesions in MOG-ab patients (p = .019). Large lesions and U- or S-shaped lesions were also more frequent in MOG-ab (p < .000 and p = .013, respectively). Half of the MOG-ab patients had spinal cord involvement, and 36.5% presented with longitudinally extensive transverse myelitis (LETM). However, among the MOG-ab and AQP4-ab patients with spinal attack, there was no significant difference in the proportion with LETM (p = .057). In conclusion, a higher proportion of MOG-ab patients than AQP4-ab patients had brain lesions in white matter. Among MOG-ab patients who had an attack in the spinal cord, 65.5% also had LETM during the disease course. Conus medullaris lesions were rare in Chinese MOG-ab patients.