Miller Fisher syndrome following COVID-19 vaccines: A scoping review.

BACKGROUND AND PURPOSE: Miller Fisher syndrome (MFS), a variant of Guillain-Barré Syndrome (GBS), could be underestimated in evaluations of its adverse events (AEs) following COVID-19 vaccination. We aimed to identify and characterize MFS following COVID-19 vaccination. MATERIALS AND METHODS: Relevant studies reported on during the COVID-19 pandemic were identified in the MEDLINE, Embase, and other databases. RESULTS: Nine cases of MFS following COVID-19 vaccination from various regions were included. Unlike MFS following COVID-19 infection, patients with MFS following COVID-19 vaccination frequently presented with anti-GQ1b antibody positivity (44%, 4/9). Unlike GBS following COVID-19 vaccination, only two of nine (22%) cases of MFS following COVID-19 vaccination had developed after viral-vector-related vaccine administration. CONCLUSIONS: Miller Fisher syndrome following COVID-19 vaccination seems to have a different pathophysiology from MFS following COVID-19 infection and GBS following COVID-19 vaccination. This neurological syndrome with a rare incidence and difficulty in diagnosis should be considered an AE of COVID-19 vaccination.

Genotype and Phenotype Differences in CADASIL from an Asian Perspective.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary cerebral small-vessel disease caused by mutations in the NOTCH3 gene. Classical pathogenic mechanisms are associated with cysteine gain or loss, but recent studies suggest that cysteine-sparing mutations might have a potential role as a pathogen. In comparison with CADASIL patients in Western countries, there are several differences in Asian patients: (1) prevalent locus of NOTCH3 mutations (exons 2-6 [particularly exon 4] vs. exon 11), (2) age at symptom onset, (3) prevalence of cerebral microbleeds and hemorrhagic stroke, (4) clinical symptoms, and (5) severity of white matter hyperintensities and typical involvement of the anterior temporal pole in magnetic resonance imaging. Both ethnicity and founder effects contribute to these differences in the clinical NOTCH3 spectrum in different cohorts. More functional investigations from diverse races are needed to clarify unknown but novel variants of NOTCH3 mutations. This review may broaden the spectrum of NOTCH3 variants from an Asian perspective and draw attention to the hidden pathogenic roles of NOTCH3 variants.

Comparison of MOG and AQP4 antibody seroprevalence in Korean adults with inflammatory demyelinating CNS diseases.

We aimed to compare seroprevalence of anti-myelin oligodendrocyte glycoprotein (MOG) and anti-aquaporin-4 (AQP4) antibodies in Korean adults with inflammatory demyelinating diseases (IDDs) of the central nervous system (CNS), based on a multicenter nationwide database. Sera were analyzed using a live cell-based assay for MOG and AQP4 antibodies. Of 586 Korean adults with IDDs of the CNS, 36 (6.1%) and 185 (31.6%) tested positive for MOG and AQP4 antibodies, respectively. No participant showed double positivity. Seroprevalence of MOG antibodies was about five times lower than that of AQP4 antibodies in a large cohort of Korean adults with IDDs of the CNS.

Finger drop sign as a new variant of acute motor axonal neuropathy.

We propose the finger drop sign as a new clinical variant of acute motor axonal neuropathy (AMAN) defined by immunological and radiological evidence. We identified eight consecutive patients who had AMAN. All of them developed prominent involvement of the finger extensors. We performed magnetic resonance imaging (MRI) of the extremity muscles and serological assays for antiganglioside antibodies and Campylobacter jejuni. Patients with AMAN showed characteristic and a markedly sustained weakness of the finger extensors with a distinctive pattern of the finger drop sign. Limb MRI revealed unevenly distributed abnormal signals in the muscles mainly innervated by the posterior interosseous nerve. All tested patients showed positivity for immunoglobulin G antibody against ganglioside complex of GM1 and phosphatidic acid. A pathophysiological understanding of this unique syndrome can provide further insight into antiganglioside-antibody-mediated axonal injury in Guillain-Barré syndrome.

Epidemiology of ALS in Korea using nationwide big data.

OBJECTIVE: This study aimed to determine the incidence, prevalence and survival time of Korean patients with amyotrophic lateral sclerosis (ALS) using National Health Insurance Service (NHIS) data. METHODS: Using NHIS data, the Korean nationwide health dataset, we identified patients with motor neuron diseases who were first diagnosed with a KCD-6 code (G12.20-G12.28; modified from ICD-10 codes) between 2011 and 2015. ALS (G12.21 code) epidemiological characteristics, including annual incidence, prevalence, mortality rates and survival time, were analysed and compared with sociodemographic variables. RESULTS: New patients with ALS (n=3049) were enrolled over 5 years. The mean annual incidence was 1.20/100 000, and the sex ratio was 1.60 (male:female). The mean age at the time of diagnosis was 61.4 years. The prevalence rate was 3.43/100 000 in 2015. In this period, riluzole was prescribed to 53.6% of patients with ALS. Furthermore, 20.3% of patients with ALS underwent tracheostomy. When analysed for age and socioeconomic status, ALS prevalence rate was 10.71 in the aged group (≥60) in 2015 and was lowest in the middle-income group compared with that in the high-income and low-income groups. The estimated mean survival time in this population was 50.0 months, and the 3-year and 5-year mortality rates were 52.1% and 63.7%, respectively. CONCLUSIONS: This study is the first nationwide survey for epidemiological characteristics of ALS in Korea using national data. The use of these data substantially advances the understanding of Korean and Asian ALS epidemiology and its relationship with socioeconomic status, age and sex.

Validity and Reliability of the Fibromyalgia Rapid Screening Tool Among Individuals with Chronic Daily Headache: A Clinic-Based Study.

BACKGROUND: Fibromyalgia is a common chronic pain disorder typically associated with headache disorders, particularly chronic daily headache. However, fibromyalgia is typically underdiagnosed and undertreated. The Fibromyalgia Rapid Screening Tool questionnaire is a brief, self-administered questionnaire composed of six "yes/no" questions for detecting fibromyalgia. The Fibromyalgia Rapid Screening Tool questionnaire has demonstrated high sensitivity and specificity among patients with chronic diffuse pain conditions. This study assessed the validity and reliability of the aforementioned questionnaire for detecting fibromyalgia among patients with chronic daily headache. METHODS: Consecutive first-visit headache patients with primary chronic daily headache (≥15 days/month for three or more months) at the outpatient clinics of four university hospitals were enrolled in this study from April 2015 to October 2015, and the validity and reliability of the Fibromyalgia Rapid Screening Tool questionnaire for determining fibromyalgia were evaluated. Fibromyalgia was diagnosed according to the American College of Rheumatology criteria of 2010. RESULTS: A total of 171 patients with primary chronic daily headache were recruited, and 100 (58.4%) were determined to have fibromyalgia. Receiver operating characteristic curve analysis revealed that a cutoff score of 5 (corresponding to the number of positive items) provided the highest rate of correct identification of patients (77.2%), with a sensitivity of 70.0% and specificity of 87.3%. The positive and negative predictive values were 88.6% and 67.4%, respectively. The Cronbach's alpha coefficient was 0.684. CONCLUSIONS: The Fibromyalgia Rapid Screening Tool is a valid and reliable instrument for identifying fibromyalgia among patients with chronic daily headache.

Unusual Intracranial Arterial Calcification and Vitamin D Deficiency.

Although intracranial arterial calcifications (IACs) are encountered in approximately 85% of patients with acute ischemic stroke (IS), the significance of IAC in plaque instability is still controversial. Because most tissues including brain tissue have vitamin D receptors, vitamin D deficiency might play multiple roles in variable sites. Here, we report a novel presentation of IS with IAC including anterior cerebral artery involvement due to vitamin D deficiency. In conclusion, although the role of IAC in cerebral infarction is still controversial, we suggest that insufficient vitamin D should be examined and treated appropriately in all patients with IS. We believe that this article provides important implications for the treatment of vitamin D deficiency in patients with IS.

Fibromyalgia Among Patients With Chronic Migraine and Chronic Tension-Type Headache: A Multicenter Prospective Cross-Sectional Study.

OBJECTIVES: To investigate the frequency and impact of fibromyalgia among patients with chronic migraine (CM) and chronic tension-type headache (CTTH). BACKGROUND: Fibromyalgia (FM) is a common comorbidity in patients with chronic headaches. CM and CTTH are the two common types of chronic headaches. METHODS: We conducted a cross-sectional study in neurology outpatient clinics of four university hospitals and selected first-visit 136 patients with CM and 35 patients with CTTH. FM was assessed based on the 2010 American College of Rheumatology diagnostic criteria. RESULTS: The frequency of FM was significantly higher among patients with CM when compared to those with CTTH (91/136 [66.9%] vs 9/35 [25.7%], P < .001). Logistic regression analyses revealed an increased odds ratio (OR) for FM for patients with CM when compared to those with CTTH after adjustment for age, sex, anxiety, depression, and insomnia (OR = 3.6, 95% confidence interval = 1.1-11.4). Furthermore, CM patients with FM had higher scores in FM Impact Questionnaire compared to CTTH patients with FM (51.5 ± 16.3 vs 43.7 ± 18.7, P = .015). Comorbidity of FM was associated with increased frequency of photophobia, phonophobia, anxiety, depression, and insomnia among patients with CM. Such association was not noted among patients with CTTH. CONCLUSION: FM based on 2010 American College of Rheumatology diagnostic criteria was more prevalent among patients with CM than those with CTTH. Some clinical features and comorbidities of CM varied with the presence of FM.

Early discrimination of sensorimotor Guillain-Barré syndrome into demyelinating or axonal subtype by automated nerve excitability testing.

In the early stage of disease, differentiating acute inflammatory demyelinating polyneuropathy (AIDP) and acute motor sensory axonal neuropathy (AMSAN) using only a conventional nerve conduction studies (NCS) may be difficult. We evaluated the differences in the motor axonal excitability properties of 16 cases of sensorimotor Guillain-Barré syndrome by nerve excitability testing (NET). The antiganglioside antibody assay and follow-up NCS resulted in 12 patients diagnosed as AIDP and 4 patients as AMSAN. Clinical and excitability parameters in each group were compared with those in 30 normal controls. Automated NET with threshold tracking techniques was used to calculate the strength-duration time constant (SDTC), threshold electrotonus (TE), current-threshold relationship (CTR), and recovery cycle (RC) of excitability. Except for subtle changes in excitability parameters, AIDP showed no definitive difference relative to normal controls. Comparison between AMSAN and normal controls also revealed no significant differences in the SDTC, TE, and CTR parameters. However, there were clear differences in some of the RC parameters: the relative refractory period was significantly longer in the AMSAN group than in the AIDP group (4.40 ± 1.11 vs. 3.09 ± 1.01 ms, mean ± SEM; p < 0.001), while superexcitability was significantly less prominent in the AMSAN group (-6.80 ± 10.30 vs. -26.48 ± 1.17%, mean ± SEM; p < 0.001). Our study identified that both AIDP and AMSAN were associated with subtle changes in excitability properties. Nonetheless, the prominent increase in refractoriness in AMSAN suggests the presence of a nodal conduction block.

Searching the Footprints of Pioneers on Neurology: A Bibliometric Analysis.

BACKGROUND: We identify the most cited articles that have influenced the clinical practices of neurologists. METHODS: We first analyzed the top 100 cited articles published in 50 neurology journals with high impact factors. We collected all of the original articles on clinical neurology published in all 554 medical journals. The Institute for Scientific Information Web of Science search tools were used to identify the top 100 cited articles in the database of Journal Citation Reports since 1950, which were then manually reviewed to discover their contents. RESULTS: In the first part of analysis, the top 100 cited articles were all published in 17 journals, with 26 articles published in Neurology. The most frequent topic subject of neurodegeneration appeared in 40 articles. The second part of the analysis revealed that the top 100 cited articles were also all published in 17 journals, with 30 articles published in New England Journal of Medicine. In contrast to the first part of the analysis, stroke was the most frequent topic subject (in 38 articles). CONCLUSIONS: Our bibliometric analysis has yielded 2 detailed lists of the top 100 cited articles that were listed separately using different methods. This approach can provide information about the trends and academic achievements in the field of clinical neurology.

Citation Classics in Stroke: The Top-100 Cited Articles on Hemorrhagic Stroke.

BACKGROUND: Stroke is a disastrous disease and a major health burden worldwide, especially in Korea. Hemorrhagic stroke (HS) accounts for approximately 20% of all the types of strokes. It is important to be able to evaluate stroke diagnoses and evolving treatments. OBJECTIVE: We aimed to identify the top-100 cited articles and assess a paradigm shift that occurred in the field of HS. METHODS: We searched all articles that had been cited more than 100 times using the Web of Science citation search tool during January 2016. Among a total of 2,651 articles, we identified the top-100 cited articles on HS. RESULTS: The number of citations for the articles analyzed in this study ranged from 1,746 to 211, and the number of annual citations ranged from 125.6 to 5.5. Most of the articles that were published in Stroke (35%) and Journal of Neurosurgery (22%), originated in the United States (n = 56), were original articles (64%), and dealt with the natural history or etiology (n = 37) and vasospasm in subarachnoid hemorrhage (n = 8). CONCLUSIONS: We analyzed the top-100 cited articles in the field of HS based on citation rates. The results provide a unique perspective on historical and academic developments in this field.

The 100 most-cited articles in neuroimaging: A bibliometric analysis.

The purpose of our study was to identify and characterize the 100 most-cited articles in neuroimaging. Based on the database of Journal Citation Reports, we selected 669 journals that were considered as potential outlets for neuroimaging articles. The Web of Science search tools were used to identify the 100 most-cited articles relevant to neuroimaging within the selected journals. The following information was recorded for each article: publication year, journal, category and impact factor of journal, number of citations, number of annual citations, authorship, department, institution, country, article type, imaging technique used, and topic. The 100 most-cited articles in neuroimaging were published between 1980 and 2012, with 1995-2004 producing 69 articles. Citations ranged from 4384 to 673 and annual citations ranged from 313.1 to 24.9. The majority of articles were published in radiology/imaging journals (n=75), originated in the United States (n=58), were original articles (n=63), used MRI as imaging modality (n=85), and dealt with imaging technique (n=45). The Oxford Centre for Functional Magnetic Resonance Imaging of the Brain at John Radcliffe Hospital (n=10) was the leading institutions and Karl J. Friston (n=11) was the most prolific author. Our study presents a detailed list and an analysis of the 100 most-cited articles in the field of neuroimaging, which provides an insight into historical developments and allows for recognition of the important advances in this field.

Top-100 cited articles on Guillain-Barré syndrome: a bibliometric analysis.

Since the first description of Guillain-Barré syndrome (GBS) 100 years ago, the concept of this syndrome has changed remarkably. The purpose of our study was to identify and characterize the most-cited articles that have contributed to advancing the understanding of GBS. Based on the database of Journal Citation Reports, we selected 554 journals that were considered as potential sources of reports on studies related to clinical neurology and general medicine. The Web of Science search tools were used to identify the most-cited articles relevant to GBS or other variants in the selected journals. Of the selected articles, 18 were review articles and the remainder were original articles or included only a few case series. Among the original articles, 13 described basic research associated with immunological pathogenesis involving anti-ganglioside antibodies. Most of the original studies (42/64, 66%) published after 1990 evaluated anti-ganglioside antibodies that mediated axonal GBS or Miller Fisher syndrome, with only a small number of the papers involving electrodiagnostic medicine (n = 4). Our bibliometric analysis has yielded a detailed list of the top-100 cited articles in the field of GBS.

Comparison of new adenosine diphosphate receptor antagonists with clopidogrel in patients with coronary artery disease: a meta-analysis.

Recent data suggest the superiority of new adenosine diphosphate (ADP) receptor antagonists compared with clopidogrel in acute coronary syndrome patients. We aimed to assess the risks and benefits of new ADP receptor antagonists in patients with coronary artery disease (CAD). Relevant studies published through February 28, 2014 were searched and identified in the MEDLINE, EMBASE, and Cochrane databases. Summary estimates were obtained using a random-effects model. All nine published randomized controlled studies comparing new ADP receptor antagonists with clopidogrel in CAD were included. The database consisted of 66,900 patients; 33,782 on novel agents, and 33,118 on clopidogrel. New ADP receptor antagonists reduced the composite incidence of all-cause mortality, myocardial infarction or stroke (odds ratio [OR] 0.89, 95 % confidence interval [CI] 0.81-0.97, p = 0.01) but increased the incidence of non-coronary artery bypass grafting-related major bleeding (OR 1.24, 95 % CI 1.08-1.42, p = 0.003). The composite end point of the net rate of adverse clinical events, which was the combination of the primary efficacy end point and the primary safety end point, was significantly lower in the new agent group compared to the clopidogrel group (9.7 versus 10.6 %, OR 0.92, 95 % CI 0.85-1.00). Use of recently introduced new ADP receptor antagonists results in a reduction in adverse clinical outcomes but a substantial increase in bleeding. New agents revealed an improved combined efficacy and safety outcome compared to that of clopidogrel in patients with CAD.

AWAJI criteria are not always superior to the previous criteria: A meta-analysis.

INTRODUCTION: Recently, some authors have claimed that the Awaji criteria (AC) are not always more sensitive than the revised El Escorial criteria (rEEC) in amyotrophic lateral sclerosis (ALS). METHODS: A meta-analysis examined 2 prospective and 7 retrospective studies, which included 1,121 ALS patients, to compare AC and rEEC for early diagnosis of ALS. RESULTS: AC led to an 11% greater likelihood of being classified into the categories "clinically definite" or "clinically probable", while if confined to the "clinically probable - laboratory supported (LS)" category, this effect was 40% higher with the rEEC (95% cnfidence interval, 3-82%; I2=98%). Specifically, AC downgraded 20% of the rEEC "clinically probable - LS" category to the AC "clinically possible". CONCLUSIONS: Despite overall superiority of AC, this meta-analysis shows that it is not always more sensitive than rEEC. These results are related to the requirement for 2 upper motor neuron signs in the AC "clinically probable" category.

Brain MRI in neuropsychiatric lupus: associations with the 1999 ACR case definitions.

The purpose of this study was to identify the characteristic magnetic resonance imaging (MRI) findings in neuropsychiatric systemic lupus erythematosus (NPSLE) and to investigate the association between MRI findings and neuropsychiatric manifestations in SLE. Brain MRIs with a diagnosis of SLE from 2002 to 2013 from three tertiary university hospitals were screened. All clinical manifestations evaluated by brain MRI were retrospectively reviewed. If the clinical manifestations were compatible with the 1999 NPSLE American College of Rheumatology (ACR) nomenclature and case definitions, the brain MRIs were assessed for the presence of white matter hyperintensities, gray matter hyperintensities, parenchymal defects, atrophy, enhancement, and abnormalities in diffusion-weighted images (DWI). The number, size, and location of each lesion were evaluated. The neuropsychiatric manifestation of each brain MRI was classified according to the 1999 ACR NPSLE case definitions. The associations between MRI findings and NPSLE manifestations were examined. In total, 219 brain MRIs with a diagnosis of SLE were screened, and 133 brain MRIs met the inclusion criteria for NPSLE. The most common MRI abnormality was white matter hyperintensities, which were observed in 76 MRIs (57.1 %). Gray matter hyperintensities were observed in 41 MRIs (30.8 %). Parenchymal defects were found in 31 MRIs (23.3 %), and atrophy was detected in 20 MRIs (15.0 %). Patients who had seizures were more associated with gray matter hyperintensities than patients with other neuropsychiatric manifestations. Patients with cerebrovascular disease were more associated with gray matter hyperintensity, parenchymal defects, and abnormal DWI than patients with other neuropsychiatric manifestations. In addition to white matter hyperintensities, which were previously known as SLE findings, we also noted the presence of gray matter hyperintensities, parenchymal defects, and abnormal DWI in a substantial portion of SLE patients, particularly in those with cerebrovascular disease or seizures.

Guillain-Barré syndrome in Asia.

Over the past 20 years, the most notable advance in understanding Guillain-Barré syndrome (GBS) has been the identification of an axonal variant. This advance arose chiefly through studies undertaken in East Asian countries and comprised two major aspects: first, the immunopathogenesis of axonal GBS related to anti-ganglioside antibodies and molecular mimicry of Campylobacter jejuni; and second, the observation that distinct electrophysiological patterns of axonal GBS existed, reflecting reversible conduction failure (RCF). As a consequence, the pathophysiology of acute motor axonal neuropathy (AMAN) has perhaps become better understood than acute inflammatory demyelinating polyneuropathy. Despite these more recent advances, a critical issue remains largely unresolved: whether axonal GBS is more common in Asia than in Europe or North America. If it is more common in Asia, then causative factors must be more critically considered, including geographical differences, issues of genetic susceptibility, the role of antecedent infections and other potential triggering factors. It has become apparent that the optimal diagnosis of AMAN requires serial electrophysiological testing, to better delineate RCF, combined with assessment for the presence of anti-ganglioside antibodies. Recent collaborative approaches between Europe and Asia have suggested that both the electrophysiological pattern of AMAN and the seropositivity for anti-ganglioside antibodies develop similarly. Separately, however, current electrodiagnostic criteria for AMAN limited to a single assessment appear inadequate to identify the majority of cases. As such, diagnostic criteria will need to be revised to improve the diagnostic sensitivity for AMAN.

Impact of Systolic Blood Viscosity on Deep White Matter Hyperintensities in Patients With Acute Ischemic Stroke.

BACKGROUND: Elevated blood viscosity (BV), a critical determinant in blood rheology, is a contributing factor in cerebrovascular diseases. The specific influence of BV on small vessel disease burden remains unexplored. This study aims to examine the relationship between BV and regional white matter hyperintensity (WMH) volume in patients with acute ischemic stroke. METHODS AND RESULTS: We enrolled a cohort of 302 patients with acute ischemic stroke or transient ischemic attack who were admitted to a hospital within 7 days of symptom onset in this study. We measured whole BV using a scanning capillary-tube viscometer and categorized systolic blood viscosity into 3 groups based on established references. We quantified and normalized WMH volumes using automated localization and segmentation software by NEUROPHET Inc. We performed multivariable logistic regression analysis to assess the correlation between systolic BV and WMH. The mean subject age was 66.7±13.4 years, and 38.7% (n=117) of the participants were female. Among a total of 302 patients, patients with higher deep WMH volume (T3) were typically older and had an atrial fibrillation, strokes of cardioembolic or undetermined cause, elevated levels of C-reactive protein, diastolic blood viscosity and systolic BV. A multivariable adjustment revealed a significant association between high systolic BV and increased deep-WMH volume (odds ratio [OR], 2.636 [95% CI, 1.225-5.673]). CONCLUSIONS: Elevated systolic BV is more likely to be associated with deep WMH volume in patients with acute ischemic stroke or transient ischemic attack. These findings reveal novel therapeutic strategies focusing on blood rheology to enhance cerebral microcirculation in stroke management.

Serial Nerve Conduction Studies in Guillain-Barré Syndrome: Its Usefulness and Precise Timing.

PURPOSE: Nerve conduction study (NCS) is essential for subclassifying Guillain-Barré syndrome (GBS). It is well known that the GBS subclassification can change through serial NCSs. However, the usefulness of serial NCSs is debatable, especially in patients with early stage GBS. METHODS: Follow-up NCS data within 3 weeks (early followed NCS, EFN) and within 3 to 10 weeks (late-followed NCS, LFN) were collected from 60 patients with GBS who underwent their first NCS (FN) within 10 days after symptom onset. Each NCS was classified into five subtypes (normal, demyelinating, axonal, inexcitable, and equivocal), according to Hadden's and Rajabally's criteria. We analyzed the frequency of significant changes in classification (SCCs) comprising electrodiagnostic aggravation and subtype shifts between demyelinating and axonal types according to follow-up timing. RESULTS: Between FN and EFN, 33.3% of patients with Hadden's criteria and 18.3% with Rajabally's criteria showed SCCs. Between FN and LFN, 23.3% of patients with Hadden's criteria and 21.7% with Rajabally's criteria showed SCCs, of which 71.4% (Hadden's criteria) and 46.2% (Rajabally's criteria) already showed SCCs from the EFN. The conditions of delayed SCCs between EFN and LFN were very early FN, mild symptoms at the FN, or persistent electrophysiological deterioration 3 weeks after symptom onset. CONCLUSIONS: A substantial proportion of patients with GBS showed significant changes in neurophysiological classification at the early stage. Serial NCS may be helpful for precise neurophysiological classification. This study suggests that follow-up NCSs should be performed within 3 weeks of symptom onset in patients with GBS in whom FN was performed within 10 days of symptom onset.