Lancet Neurol Annual Review: Epilepsy in Neurology Summary 2021

2021 faces challenges related to the COVID-19 pandemic, but there is still a lot of progress in epilepsy research
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The journal The Lancet Neurology has conducted an annual inventory of epilepsy research and concluded that epilepsy research in 2021 has made progress in many areas
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 A highlight of the year was a greater understanding of the role of astrocytes in epileptogenesis
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The role of neurons in epileptogenesis has been extensively studied
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By describing the detailed role of astrocytes in regulating excitatory glutamate release and maintaining homeostasis of extracellular potassium concentrations in the synaptic cleft, the importance of astrocytes in the development of epileptogenesis has now been analyzed
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Astrocytes have a strong control over the excitability of neurons and their information processing patterns
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In transgenic mice with astrocyte-specific expression of pH sensors, astrocytes respond to epileptiform activity through intracellular alkalinization
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This finding suggests that alkaline pH changes in astrocytes can cause gap junction uncoupling, hindering potassium clearance, which can lead to seizures
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This concept is consistent with the finding of ictal slow changes (ictal DC changes) in astrocyte functional syncytia production that occur prior to onset of conventional ictal EEG patterns in focal epilepsy patients by pre-epilepsy surgery of invasive EEG recordings were assessed
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 Other interesting research advances are in the mathematical modeling of invasive EEG (electroencephalography) during seizures and the use of virtual brain models
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A nonlinear dynamic mathematical model was applied to invasive EEG during seizures and led to new proposals for epilepsy classification
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From an analysis of more than 2000 patients with focal seizures from multiple centers, 16 dynamical patterns were proposed by examining the fast and slow EEG components from a principle of operation perspective
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Further development of the mathematical model, combined with structural information from diffusion-weighted MRI noninvasive brain imaging, from individual neurons to neural populations, has resulted in the construction of large-scale brain network models in patients
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This modeling enables clinicians to account for changes in the spatiotemporal organization of brain dynamics by integrating clinical hypotheses of epileptogenic regions prior to surgery, such as epilepsy foci resection
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 Another interesting finding was in patients with benign adult familial myoclonic epilepsy (BAFME)
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This rare disorder is autosomal dominant and is characterized by myoclonic tremor and epilepsy
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Aberrant expansions of TTTCA and TTTTA repeats were found in SAMD12 intron 4 in patients with BAFME1 (mainly in Japan) and other STARD7 introns in BAFME2 patients (mainly in Europe)
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These noncoding repeat expansions lead to common clinical features (cortical tremors, rare generalized tonic-clonic seizures, absence of cerebellar symptoms, and intellectual disability)
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Other types of BAFME (3, 4, 6, and 7) have different genetic abnormalities, but the introns of each gene typically have expansions of TTTTA and TTTCA
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Furthermore, because TTTTA expansions in TNRC6A responsible for BAFME6 (a rare type of BAFME in Japan) frequently occur with mutations in SAMD12, TTTCA repeat insertions in SAMD12 have been shown to be pathogenic, whereas TTTTA repeat expansions in TNRC6A are non-causal Pathological, which suggests that there may be an unknown factor in the ancestry of BAFME patients, as TTTTA expansion in TNRC6A causes BAFME6 (a rare type of BAFME in Japan) that often occurs with SAMD12 mutations, but clinical symptoms are not caused by this additional expansion of TNRC6A.
increase and change
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 Research has also advanced in the diagnosis of autoimmune encephalitis by using sign and symptom scores
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Antibodies contributing to the Focal Epilepsy Signs and Symptoms (ACES) score included six factors: medial temporal lobe MRI hyperintensity, autoimmune disease, behavioral changes, autonomic symptoms, cognitive symptoms, and speech problems
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It was found on the basis of prospectively collected data on patients with focal epilepsy of unknown origin; this score can be used to guide screening for autoimmune causes of seizures
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ACES scores were subsequently validated in a second external cohort
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An ACES score of at least 2 had 100% sensitivity and 84.
9% specificity for diagnosing autoimmune seizures
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 Finally, research in the field of big data analysis and epilepsy-induced networks has also yielded results
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Subdural electrode implantation is very popular in epilepsy surgery, but the procedure has been gradually replaced by stereotaxic electroencephalography (SEEG)
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This transition occurs because cortical malformations, an important and most common drug-resistant epilepsy disorder, are often buried in subcortical areas beyond those recorded by subdural electrodes
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In addition, epileptogenic networks as ictal propagation have been highlighted for the control of even focal epilepsy, and multiple SEEGs better delineate focal epilepsy than subdural electrodes
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However, direct comparisons of clinical utility between the two approaches and big data remain to be studied in the real world
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 The International League Against Epilepsy Surgical Treatment Committee conducted an international registry of patients with invasive EEG implantation between 2005 and 2019, including 2012 patients, of whom 1468 (72.
9%) were eligible for analysis (526 with subdural electrodes) , 942 passed SEEG)
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Subdural electrode assessment is more beneficial than SEEG for brain surgery in patients with drug-resistant epilepsy, but has more surgical complications and is less likely to be seizure-free
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Regarding the concept of epileptogenic networks, closed-loop medial septal electrical stimulation can rapidly terminate intrahippocampal seizures and suppress secondary generalization in the rat ignition model by intervening temporally targeted surrogate stimulation of pathological oscillations
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 The fundamental purpose of most epilepsy research questions is to help people with epilepsy and related neurological disorders, which is consistent with the goals of the ongoing global anti-epileptic movement
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Year-end inventory ☟☟☟ 2021 neurology image reading good article summary 2021 neurology unmissable guidelines and consensus 2021 neurology classic cases Top 12, help you develop clinical thinking not to be missed! 2021 Inventory of FDA-approved Drug Treatments in Neurology 2021 Summary of Clinical Basis in Neurology Compiled from: Ikeda A.
Epilepsy research in 2021: multidisciplinary achievements.
Lancet Neurol.
2022 Jan;21(1):8-10.
doi: 10.
1016/S1474-4422(21)00421-X.
PMID: 34942141.