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The involvement of cranial nerves is being increasingly recognised in COVID-19. This review aims to summarize and discuss the recent advances concerning the clinical presentation, pathophysiology, diagnosis, treatment, and outcomes of SARS-CoV-2 associated cranial nerve mononeuropathies or polyneuropathies. Therefore, a systematic review of articles from PubMed and Google Scholar was conducted. Altogether 36 articles regarding SARS-CoV-2 associated neuropathy of cranial nerves describing 56 patients were retrieved. Out of these 56 patients, cranial nerves were compromised without the involvement of peripheral nerves in 32 of the patients, while Guillain-Barre syndrome (GBS) with cranial nerve involvement was described in 24 patients. A single cranial nerve was involved either unilaterally or bilaterally in 36 patients, while in 19 patients multiple cranial nerves were involved. Bilateral involvement was more prevalent in the GBS group (n=11) as compared to the cohort with isolated cranial nerve involvement (n=5). Treatment of cranial nerve neuropathy included steroids (n=18), intravenous immunoglobulins (IVIG) (n=18), acyclovir/valacyclovir (n=3), and plasma exchange (n=1). The outcome was classified as “complete recovery” in 21 patients and as ”partial recovery” in 30 patients. One patient had a lethal outcome. In conclusion, any cranial nerve can be involved in COVID-19, but cranial nerves VII, VI, and III are the most frequently affected. The involvement of cranial nerves in COVID-19 may or may not be associated with GBS. In patients with cranial nerve involvement, COVID-19 infections are usually mild. Isolated cranial nerve palsy without GBS usually responds favorably to steroids. Cranial nerve involvement with GBS benefits from IVIG. 

Sudden and unexpected death in epilepsy (SUDEP) is the most common type of death among patients with epilepsy. Here, we address the importance of the experimental models in search of the mechanisms underlying SUDEP. Most studies have investigated the cardiovascular responses in animal models of epilepsy. However, there are few proposed SUDEP models in literature. Hypoventilation, apnea, respiratory distress, pulmonary hypertension, autonomic dysregulation and arrhythmia are common findings in epilepsy models. Impairments on adenosinergic and serotonergic systems, brainstem spreading depolarization, seizure-activation of neural substrates related to cardiorespiratory control, altered autonomic control, and mutations on sodium and potassium channels are hypothesis suggested. Overall, current research highlights the evident multifactorial nature of SUDEP, which involves acute and chronic aspects ranging from systemic to molecular alterations. Thus, we are convinced that elucidation and prevention of SUDEP can be achieved only through the interaction between basic and clinical science.

Article temporal lobe epilepsy with mesial temporal sclerosis: hippocampal neuronal loss as a predictor of surgical outcome Epilepsia do lobo temporal com esclerose mesial temporal: o padrão da perda neuronal hipocampal como preditor do prognóstico cirúrgico Anaclara Prada Jardim¹, Rafael Scarpa da Costa Neves¹, Luís Otávio Sales Ferreira Caboclo¹, Carmen Lucia Penteado Lancellotti² , ³, Murilo Martinez Marinho¹, Ricardo Silva Centeno¹, Esper Abrão Cavalheiro 4 , Carla Alessandra Scorza 4 , Elza Márcia Targas Yacubian¹Mesial temporal sclerosis (MTS) is the most common pathological finding in drug refractory, chronic temporal lobe epilepsy (TLE) 1 . Mesial temporal lobe structures with a sclerotic hippocampus have been considered the site of seizure onset for most TLE patients, and hippocampal sclerosis (HS) has been considered essential for MTS diagnosis. Surgery has become the treatment of choice in the management of patients with this epilepsy syndrome 2,3 . Tailored resections of temporal neocortex and mesial temporal structures, including hippocampus and amygdala, are an established epilepsy treatment modality and offer a favorable outcome in approximately two-thirds of patients 4,5 .The reason why around one-third of individuals with this epilepsy syndrome still present seizures after surgical treatment ABStrActObjective: To analyze retrospectively a series of patients with temporal lobe epilepsy (TLE) and mesial temporal sclerosis (MTS), and the association of patterns of hippocampal sclerosis with clinical data and surgical prognosis. Method: Sixty-six patients with medically refractory TLE with unilateral MTS after anterior temporal lobectomy were included. Quantitative neuropathological evaluation was performed on NeuN-stained hippocampal sections. Patient's clinical data and surgical outcome were reviewed. Results: Occurrence of initial precipitating insult (IPI), as well as better postoperative seizure control (i.e. Engel class 1), were associated with classical and severe patterns of hippocampal sclerosis (MTS type 1a and 1b, respectively). Conclusion: Quantitative evaluation of hippocampal neuronal loss patterns predicts surgical outcome in patients with TLE-MTS.Key words: epilepsy, temporal lobe, mesial temporal sclerosis, hippocampal sclerosis, pathology, surgical prognosis. reSUMO Objetivo: Analisar retrospectivamente uma série de pacientes com epilepsia do lobo temporal (ELT) e esclerose mesial temporal (EMT), bem como correlacionar os padrões de esclerose hipocampal com os dados clínicos e o prognóstico cirúrgico. Métodos: Foram incluídos neste estudo 66 pacientes com ELT refratária a tratamento medicamentoso e com EMT unilateral submetidos à lobectomia temporal anterior. A análise neuropatológica quantitativa foi realizada em seções hipocampais imunomarcadas com NeuN. Dados clínicos e resultados do acompanhamento pós-cirúrgico foram revisados. Resultados: Ocorrência de evento precipitante inicial e melhor controle de crises após a cirurgia (i.e. classe 1 de Engel) foram associados aos pad...

Human hippocampal slice preparations from patients with temporal lobe epilepsy (TLE) associated with hippocampal sclerosis (HS) are excellent material for the characterization of epileptiform-like activity. However, it is still unknown if hippocampal regions as cornu Ammonis (CA) 1, CA3 and CA4, generate population epileptiform-like activity. Here, we investigated epileptiform activities of the subiculum, CA1, CA2, CA3, CA4 (induced by elevation of extracellular potassium concentration) and the dentate gyrus (induced with hilar stimulation and elevation of potassium concentration) from sclerotic hippocampi of patients with drug-resistant TLE. Five types of epileptiform-like activity were observed: interictal-like events; periodic ictal spiking; seizure-like events; spreading depression-like events; tonic seizure-like events and no activity. Different susceptibilities to generate epileptiform activity among hippocampal regions were observed; the dentate gyrus was the most susceptible region followed by the subiculum, CA4, CA1, CA2 and CA3. The incidence of epileptiform activity pattern was associated with specific regions of the hippocampal formation. Moreover, it was observed that each region of the hippocampal formation exhibits frequency-specific ranges in each subfield of the sclerotic human tissue. In conclusion, this study demonstrates that epileptiform-like activity may be induced in different regions of the hippocampal formation, including regions that are severely affected by neuronal loss.