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Although activation of astrocytes is critical in developing neuropathic pain (NP) following nerve injury, the underlying mechanisms of NP and therapeutic management for NP are still vague. Importantly, the decreases in the levels of astrocytic glutamate transporter‐1 (GLT‐1) in the spinal dorsal horn result in enhanced excitatory transmission and cause persistent pain. P2Y1 purinergic receptor (P2Y1R) has been shown to enhance many inflammatory processes. The up‐regulated expression of astrocytic P2Y1R is crucial to participate in pain transduction under conditions of nerve injury and peripheral inflammation considering that P2Y1R is potentially involved in glutamate release and synaptic transmission. This study indicates that the expression of P2Y1R in the spinal cord was increased accompanied by the activation of A1 phenotype astrocytes in the rat model of spinal nerve ligation (SNL). Astrocyte‐specific knockdown of P2Y1R alleviated SNL‐induced nociceptive responses and mitigated A1 reactive astrocytes, which subsequently increased GLT‐1 expression. Conversely, in naïve rats, P2Y1R over‐expression induced a canonical NP‐like phenotype and spontaneous hypernociceptive responses and increased the concentration of glutamate in the spinal dorsal horn. Besides, our in vitro data showed that the proinflammatory cytokine tumour necrosis factor‐alpha contributes to A1/A2 astrocyte reactivity and Ca2+‐dependent release of glutamate. Conclusively, our results provide novel insights that as a significant regulator of astrocytic A1/A2 polarization and neuroinflammation, P2Y1R may represent a potential target for the treatment of SNL‐induced NP. [ABSTRACT FROM AUTHOR]

The aim of this paper is to analyze the pathophysiological mechanisms acting in very early classic Guillain‐Barré syndrome (GBS) (≤4 days of symptomatic onset). In this inaugural period, both in GBS and its animal model, experimental autoimmune neuritis, the outstanding pathological feature is inflammatory edema predominating in proximal nerve trunks, particularly spinal nerves, and possibly in preterminal nerve segments. Nerve trunks external to the subarachnoid angle possess epi‐ perineurium that is relatively inelastic and of low compliance. Here such edema can increase endoneurial fluid pressure that, when sufficiently critical, may stretch the perineurium and constrict transperineurial microcirculation, compromising blood flow and producing the potential for ischemic nerve injury, whose consequence is rapid partial or complete loss of nerve excitability. These histopathological features correlate well with electrophysiological and imaging findings reported in early GBS stages. Spinal nerve edema and ischemia help to understand the pattern of Wallerian‐like degeneration observed in the axonal form of GBS, predominating in motor spinal roots at their exit from the dura matter (spinal nerves) with centrifugal distribution in more distant motor nerve trunks, and centripetal extension to the distal portion of intrathecal roots. The similarity of initial pathogenic mechanisms between demyelinating and axonal forms of GBS explains why an early increase of serum biomarkers of axonal damage is detected in both forms. In conclusion, knowledge of the microscopic anatomy of the peripheral nervous system is an essential step for a reliable understanding of pathophysiological mechanisms operating in the early phase of any classic GBS subtype. [ABSTRACT FROM AUTHOR]

Background: Vertigo is a common presenting symptom in clinical practice, predominantly of vestibular etiology, and often medicated with betahistine, despite the lack of knowledge concerning its mechanism of action. This paper's objective was to review the scientific evidence regarding the efficacy of betahistine on peripheral vertigo. Methods: A systematic search of articles written in English, published within the past 10 years, was conducted in April 2024, on online evidence-based medicine databases, using the MeSH terms "betahistine," "ménière disease," "acute vestibular neuritis," "paroxysmal vertigo," "acute peripheral vestibulopathy," and "labyrinthitis." The Strength of Recommendation Taxonomy of the American Academy of Family Physicians was used to evaluate the level of evidence and strength of recommendation. Results: This review included 12 articles for evidence analysis. Concerning Menière's disease, despite contradictory results, three of the articles analyzed showed a positive effect of betahistine, which is in line with the recommendations of the European Academy of Otology and Neurotology and NICE guidelines, while the American Academy of Otorhinolaryngology guidelines suggest offering betahistine as maintenance therapy. For benign paroxysmal positional vertigo, the established treatment is repositioning maneuvers, and three of the five studies analyzed proved the addition of betahistine to be beneficial. In regard to peripheral vertigo from other causes, two out of three articles revealed a positive recommendation for the use of betahistine. Conclusion: There is a potential benefit to the utilization of betahistine for various etiologies of peripheral vertigo. However, additional studies are required to establish more robust evidence. [ABSTRACT FROM AUTHOR]

Introduction: Human neuroblastoma cell line SH-SY5Y is a frequently used experimental cellular model in a variety of neuropsychiatric and neurodegenerative disorders. It is crucial to use a culture protocol that supports the fully differentiation of SH-SY5Y into neuron-like phenotype for the consistency of the results with neurons in vivo. However, a standardized neuronal differentiation protocol for SHSY5Y cells still does not exist. Numerous differentiation methods have been proposed in the literature, yet SH-SY5Y cells with stronger neuronal characteristics and a more favorable environment for these differentiated cells are required in order to best representation of neurons. Therefore, in the study, we aimed to establish a more successful differentiation protocol for SH-SY5Y cells based on the primary neuron culture technique, which neuronal maturation is very well defined. Methods: In the study, we rearranged previous SH-SY5Y differentiation protocols, combined them with our primary neuron culture protocol and created a robust and reproducible protocol for differentiation of SH-SY5Y. Results: Our proposed "retinoic acid+brain-derived neurotrophic factor (RA+BDNF)-induced 7 days differentiation (conalbumin- on day 4) protocol provided well developed neurites, adequate expression and localization of neuronal and synaptic markers resembling mature neurons. Conclusion: The differentiation protocol we present can enable researchers to obtain satisfactory and properly differentiated SH-SY5Y cells in each independent experiment, achieving the closest possible in vivo results. [ABSTRACT FROM AUTHOR]

Importance: Guillain-Barré syndrome (GBS)-like neuropathy mimics the leading cause of sporadic acute nontraumatic limb paralysis in individuals from developed countries. Experimental autoimmune neuritis (EAN) is an animal model of GBS and of syndromes such as acute canine polyradiculoneuritis, seen in dogs and cats. Objective: The involvement of glycogen synthase kinase (GSK)-3ß, a pro-inflammatory molecule, in rat EAN is not fully understood. This study evaluated the potential role of GSK-3ß in EAN through its inhibition by lithium. Methods: Lewis rats were injected with SP26 antigen to induce EAN. Lithium was administered from 1 day before immunization to day 14 post-immunization (PI). Then the rats were euthanized and their neural tissues were prepared for histological and Western blotting analyses. Results: Lithium, an inhibitor of GSK-3, significantly ameliorated EAN paralysis in rats, when administered from day 1 to day 14 PI. This corresponded with reduced inflammation in the sciatic nerves of EAN rats, where phosphorylation of GSK-3ß was also upregulated, indicating suppression of GSK-3. Conclusions and Relevance: These findings suggest that lithium, an inhibitor of GSK-3ß, plays a significant role in ameliorating rat EAN paralysis, by suppressing GSK-3ß and its related signals in EAN-affected sciatic nerves. [ABSTRACT FROM AUTHOR]

Immune-mediated demyelinating polyneuropathies (IMDPs) are rare disorders in which dysregulated adaptive immune responses cause peripheral nerve demyelinating inflammation and axonal injury in susceptible individuals. Despite significant advances in understanding IMDP pathogenesis guided by patient data and representative mammalian models, specific therapies are lacking. Significant knowledge gaps in IMDP pathogenesis still exist, e.g. precise antigen(s) and mechanisms that initially trigger immune system activation and identification of large population disease susceptibility factors. The initial directional cues for antigen-specific effector or autoreactive leukocyte trafficking into peripheral nerves are also unknown. An overview of current animal models, with emphasis on the experimental autoimmune neuritis and spontaneous autoimmune peripheral polyneuropathy models, is provided. Insights on the initial directional cues for peripheral nerve tissue specific autoimmunity using a novel Major Histocompatibility Complex class II conditional knockout mouse strain are also discussed, suggesting an essential research tool to study cell- and time-dependent adaptive immunity in autoimmune diseases. [ABSTRACT FROM AUTHOR]

Peripheral facial nerve palsy (PFP) is a rare occurrence after dental extraction. Early onset PFP after the procedure can be caused by trauma and/or local anesthesia, whereas delayed onset PFP has more speculative etiologies. The latter has a certain affiliation to Bell's palsy and is therefore primarily treated with corticosteroids, and long-term follow-up is often warranted. This article reports a unique case of a 30-year-old woman developing a delayed onset right-sided PFP after local intraoral anesthetic injection for molar extraction. Facial nerve injury was identified with signs of denervation and neuritis and the patient was treated with nonsteroidal anti-inflammatory drug, corticosteroids, vitamin B supplements, and mime therapy. After 9 months, the patient showed an improvement of the facial muscle activity and went from a grade IV to a grade III on the House-Brackmann grading scale. [ABSTRACT FROM AUTHOR]

Jean-Martin Charcot (1825–1893) did not show much interest in the peripheral nervous system and its associated pathologies. He found it difficult to place the peripheral nerve within his classification of disorders; it appeared to be an exception to his theories. Even the pathology that he described in 1886 with Pierre Marie (1853–1940), at the same time as Henry Tooth (1856–1925), and which is now known as Charcot-Marie-Tooth neuropathy, was considered by Charcot to be a potential myelopathy. Charcot, like other physicians, paid little heed to the observations made by Louis Duménil (1823–1890) to support the existence of primitive damage to the peripheral nerve. Charcot approached peripheral nerve pathologies through two indirect routes: amyotrophies not explained by spinal or muscular damage, and the trophic cutaneous consequences of what he called névrites (neuritis), the lesional site of which remains debated. It is noteworthy that Charcot’s approach to peripheral nervous system disorders differed from that of other neurologists of the same time. Augusta Dejerine-Klumpke (1859–1927) in France was more precise than Charcot in her anatomical and clinical descriptions, and Hugo von Ziemssen (1829–1902) in Germany made effective use of electrodiagnostics. Charcot supported the electrical work of Guillaume Duchenne de Boulogne (1806-1875), whom he sometimes presented as one of his mentors. The German physician Wilhelm Erb (1840–1921) developed electrodiagnosis by galvanic and faradic currents. Charcot never made use of Erb’s electrological advancements. With his electrophysiologist Romain Vigouroux (1831–1911), Charcot used medical electricity only for electrotherapy in hysteria. [ABSTRACT FROM AUTHOR]

Objective: This study compared the utilization and outcomes of face-to-face (F2F) vestibular support groups and online support communities (OSC) for individuals with vestibular disorders. Methods: We distributed a 31-question anonymous electronic survey through the Vestibular Disorders Association (VeDA) to F2F participants, categorizing user involvement in F2F, OSCs, or both and assessed impact on medical decision-making, psychosocial benefits, and goals achieved. Results: The F2F cohort consisted of 97 individuals comprising primarily of non-Hispanic White women (mean age = 57 years, SD ± 14 years) with diagnoses including persistent postural-perceptual dizziness (19%), Meniere's disease (15%), and vestibular neuritis (13%). Most participants were diagnosed by an otolaryngologist (65%) and attended F2F meetings monthly or less frequently (78%). The OSC group comprised of 551 individuals, primarily of non-Hispanic White women, but was younger in age (mean age = 50 years, SD ± 13 years). OSC participants notably engaged more, with 36% participating on a daily basis and 32% multiple times a week. F2F participants were older (mean age 57 years vs 50 years, P <.001) and more commonly referred by medical professionals (22% F2F vs 6% OSC, P <.001). Both groups had similar achieved goals, including hearing from others with the same diagnosis (84% vs 89%, P >.05) and similar impact on medical decision-making (75% vs 78%, P >.05). More F2F participants reported increased development of coping skills (79% F2F vs 69% OSC, P =.037). OSC participants typically found the group via an online search (75%), compared to 51% for F2F. OSC participants had higher daily engagement (36%) compared to F2F (1%). Conclusion: F2F users are older and more commonly referred by medical professionals. Despite less frequent engagement, F2F participants reported similar influences on achieved goals, medical decision-making, and impact on psychosocial benefits. These findings highlight the importance of both F2F and OSC support groups for individuals with vestibular disorders. [ABSTRACT FROM AUTHOR]

Background: A recent international consensus panel proposed diagnostic criteria for optic neuritis and a new classification. We aimed to investigate the clinical relevance of these diagnostic criteria and classification, in a cohort of patients hospitalized for a suspected diagnosis of optic neuritis. Methods: We included all patients hospitalized between 2017 and 2022 in our tertiary center for (sub)acute loss of visual acuity suggestive of optic neuritis. Clinical and paraclinical criteria obtained within the first 3 months of symptoms were collected, as well as the final diagnosis which could be optic neuritis or non-optic neuritis. We constructed a contingency table comparing diagnoses based on physician experience to those based on the recently proposed criteria. The subtypes of optic neuritis based on the new classification were compared to subtypes based on the clinician experience. Results: Two hundred fifty-seven patients were included in this study. Prevalence of optic neuritis in our cohort was 88.3%. Sensitivity and specificity of a correct diagnosis using the new criteria were, respectively, 99.5% and 86.7%. The proposed diagnostic criteria overdiagnosed four patients with optic neuritis and missed the diagnosis in one patient. According to the recent classification, idiopathic optic neuritis and clinical isolated syndrome were reclassified mainly as single isolated optic neuritis. Conclusion: In our specific cohort of patients hospitalized for acute and subacute optic neuropathy highly suspect of optic neuritis, we found that recently proposed diagnostic criteria and classification of optic neuritis are relevant for our clinical practice. Our interpretation of clinical requirement for definite and possible optic neuritis diagnosis might explain our excellent sensitivity and our high percentage of definite optic neuritis, relative to previous publications. The moderate specificity (86.7%) underlines the importance to include all contextual data in consideration for the diagnosis. The simplification of subgroups is useful, but our study highlights the complexity to find the adequate subgroup for seronegative NMOSD. [ABSTRACT FROM AUTHOR]

AbstractNeurobrucellosis is a rare complication of brucella infection which presents as meningitis, meningoencephalitis, subdural empyema, brain abscess, myelitis, and radiculo- neuritis. We report the first case of neurobrucellosis presenting as an infected cerebellopontine cistern epidermoid cyst in a young immunocompetent male who presented with fever and acute raised intracranial pressure. MRI brain showed an extra-axial mass in the right cerebellopontine angle cistern with peripheral rim enhancement and diffusion restriction. Emergency surgery unveiled a well-encapsulated lesion containing thick pus and keratinous material, confirming an infected epidermoid cyst. Intriguingly, the culture revealed Brucella infection, but the source of the infection remained unclear. [ABSTRACT FROM AUTHOR]

Background: Despite the growing use of cervical (cVEMP) and ocular (oVEMP) VEMP tests, their effectiveness in predicting chronic dizziness in vestibular neuritis (VN) patients remains unclear. Our research examines the link between long-lasting dizziness and inner ear assessments, encompassing VEMPs induced by air-conducted sound (ACS), bone-conducted vibration (BCV), and galvanic vestibular stimulation (GVS). Objectives: This study explores prognostic markers by examining the relationship between the persistence of dizziness symptoms and various inner ear test findings in VN patients. Material and methods: A retrospective cohort of 60 unilateral VN patients underwent comprehensive audiovestibular tests, including pure tone audiometry, cVEMP and oVEMP induced by ACS, BCV, GVS, and caloric tests. Patient subgroups were established based on dizziness duration: short-term (<3 months) and long-term (≥3 months). Results: No substantial correlation existed between the dizziness duration and the outcomes of any particular single inner ear test. However, patients exhibiting concurrent abnormal GVS-cVEMP and GVS-oVEMP were more likely to experience prolonged dizziness, indicating more extensive vestibular system involvement. Conclusions: Concurrent abnormalities in GVS-cVEMP and GVS-oVEMP may indicate a higher chance of long-term dizziness in VN. Significance: This study identifies concurrent abnormalities in GVS-cVEMP and GVS-VEMP as a potential prognostic marker for prolonged dizziness in VN. [ABSTRACT FROM AUTHOR]

Objective• The clinical manifestation of vertigo caused by vestibular neuritis is acute and persistent vertigo, accompanied by nausea, vomiting, and dizziness. Lowdose glucocorticoid therapy is recommended in the acute phase, while drug therapy is not recommended in the recovery phase. Therefore, it is of certain clinical value to explore other treatment options. This study hopes to better fill the current research gap in non-drug treatment of vertigo caused by vestibular neuritis. Methods • The medical data of 96 patients with vertigo caused by vestibular neuritis in our hospital from May 2019 to May 2021 were retrospectively analyzed. According to different treatment methods, they were divided into the control group (routine treatment regimen) and the experimental group (vestibular rehabilitation training combined with the medical wisdom platform), with 48 cases in each group, and the clinical efficacy of the two groups was compared. Results • The total effective rate of treatment was 95.83% in the experimental group, which was significantly higher than 79.17% in the control group (χ² = 6.095, P = .014). In the two groups, the scores of dizziness handicap inventory (DHI) and vestibular symptom index (VSI) decreased. In contrast, the scores of Tinetti performance-oriented mobility assessment (POMA) and functional independence measure (FIM) increased after treatment. After treatment, the experimental group had significantly lower DHI score (t = 12.942, P < .001), distinctly higher POMA score (t = 9.940, P < .001), overtly lower VSI score (t = 8.783, P < .001), and notably higher FIM score than the control group (t = 12.649, P < .001). Conclusion • The application of vestibular rehabilitation training combined with the medical wisdom platform is beneficial to patients with vertigo caused by vestibular neuritis, which provides reference for the subsequent treatment of this disease and has a certain clinical promotion value. [ABSTRACT FROM AUTHOR]

BACKGROUND: Clinical dynamic posturography concentrates on the pitch and roll but not on the yaw plane instability measures. This emphasis may not represent the axis instability observed in clinical stance and gait tasks for patients with balance deficits in comparison to healthy control (HC) subjects, nor the expected instability based on correlations with vestibulo-ocular reflex (VOR) deficits. To examine the axis stability changes with vestibular loss, we measured trunk sway in all three directions (pitch, roll, and yaw) during the stance and gait tasks of patients with acute unilateral vestibular neuritis (aUVN) and compared the results with those of HC. Concurrent changes in VORs were also examined and correlated with trunk balance deficits. METHODS: The results of 11 patients (mean age of 61 years) recorded within 6 days of aUVN onset were compared within those of 8 age-matched healthy controls (HCs). All subjects performed a two-legged stance task—standing with eyes closed on foam (s2ecf), a semi-gait task—walking eight tandem steps (tan8), and four gait tasks—walking 3 m with head rotating laterally, pitching, or eyes closed (w3hr, w3hp, w3ec), and walking over four barriers 24 cm high, spaced 1 m apart (barr). The tasks' peak-to-peak yaw, pitch and roll angles, and angular velocities were measured with a gyroscope system (SwayStarTM) mounted at L1-3 and combined into three, axis-specific, balance control indexes (BCI), using angles (a) for the tandem gait and barriers task, and angular velocities (v) for all other tasks, as follows: axis BCI = (2 × 2ecf)v + 1.5 × (w3hr + w3hp + w3ec)v + (tan8 + 12 × barr)a. RESULTS: Yaw and pitch BCIs were significantly (p ≤ 0.004) greater (88 and 30%, respectively) than roll BCIs for aUVN patients. For HCs, only yaw but not pitch BCIs were greater (p = 0.002) than those of roll (72%). The order of BCI aUVN vs. HC differences was pitch, yaw, and roll at 55, 44, and 31%, respectively (p ≤ 0.002). This difference with respect to roll corresponded to the known greater yaw plane than roll plane asymmetry (40 vs. 22%) following aUVN based on VOR responses. However, the lower pitch plane asymmetry (3.5%) in VOR responses did not correspond with the pitch plane instability observed in the balance control tests. The increases in pitch plane instability in UVL subjects were, however, highly correlated with those of roll and yaw. CONCLUSIONS: These results indicate that greater yaw than pitch and roll trunk motion during clinical balance tasks is common for aUVN patients and HCs. However, aUVN leads to a larger increase in pitch than yaw plane instability and a smaller increase in roll plane instability. This difference with respect to roll corresponds to the known greater yaw plane than roll plane asymmetry (40 vs. 22%) following aUVN observed in VOR responses. However, the lower pitch plane asymmetry (3.5%) in VOR responses does not correspond with the enhanced movements in the pitch plane, observed in balance control tasks. Whether asymmetries in vestibular-evoked myogenic potentials (Vemps) are better correlated with the deficits in pitch plane balance control remains to be investigated. The current results provide a strong rationale for the clinical testing of directional specific balance responses, especially yaw and pitch, and the linking of balance results for yaw and roll to VOR asymmetries. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the clinical spectrum and immediate outcomes of acute flaccid paralysis (AFP) in children presenting at National Institute of Child Health, Karachi, Pakistan. Study Design: Cross-sectional study. Setting: Department of Pediatrics, NICH, Karachi, Pakistan. Period: August 2023 to January 2024. Methods: A total of 121 children of either gender, aged 1-15 years, and presenting with AFP were analyzed. AFP was diagnosed by nerve conduction study. Causes of AFP, like Guillian Barre Syndrome (GBS), transverse myelitis, traumatic neuritis were noted. Outcomes were noted in terms of discharged from hospital, left against medical advice, and mortality. Results: In a total of 121 children, 75 (62.0%) were boys. The mean age was 6.00±2.88 years, ranging between 1-12 years. There were 74 (61.2%) children who were fully vaccinated as per age. The most common cause of AFP were GBS, transverse myelitis, and hypokalemic paralysis, noted in 49 (40.5%), 19 (15.7%), and 15 (12.4%) children, respectively. Ninety (74.4%) children were discharged after the treatment, 10 (8.3%) left against medical advice, whereas mortality was noted in 21 (17.4%) children. Children leaving against medical advice were left out from the analysis to compared final outcomes with respect to various study variables. Incomplete vaccination status (p=0.0006), and presentation with sensory loss (p=0.0003) were found to have significant association with mortality. Conclusion: Guillian Barre Syndrome was found to be the most common cause behind acute flaccid paralysis in children. Incomplete vaccination history, and presenting with sensory loss were associated with poor outcomes. [ABSTRACT FROM AUTHOR]

We present a rare case of Listeria monocytogenes (LM) rhombencephalitis with the formation of multifocal abscesses in a young immunocompetent patient. His initial symptoms of dizziness, headache, and feeling generally unwell were put down to a coincidental coinfection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The unfortunate rapid progression to trigeminal, hypoglossal, vagal, facial, and abducens nuclei palsies, and then an acquired central hypoventilation syndrome, known as Ondine's curse, required a prolonged intensive care unit (ICU) stay, and prolonged mechanical ventilation. As they continued to deteriorate despite targeted antibiotic treatment, surgical drainage of the abscesses was seen as the only meaningful available treatment option left to contain the disease. Postoperatively, the patient's strength rapidly improved as well as the severity of the cranial nerve palsies. After prolonged rehabilitation, at 3 months of follow-up, the patient was weaned off mechanical ventilation, independently mobile, and was left with only minor residual neurologic deficits. This case highlights a number of interesting findings only touched upon in current literature including the route of entry of LM into the central nervous system, the rare entity of acquired central hypoventilation syndrome, and finally the use of surgical intervention in cerebral LM infections. [ABSTRACT FROM AUTHOR]

Recent studies have highlighted the immunomodulatory effects of acupuncture on sepsis and proposed novel non-pharmacological or bioelectronic approaches to managing inflammatory illnesses. Establishing rules for selectively activating sympathetic or vagal nerve-mediated anti-inflammatory pathways using acupuncture has valuable clinical applications. Over the years, studies have revealed the segmental modulatory role of acupuncture in regulating visceral function by targeting the autonomic nervous system (ANS). In this review, we aim to summarize recent findings on acupuncture in treating sepsis, focusing on the underlying ANS mechanism, as well as the rules of acupoint specificity, intensity, frequency, and other parameters utilized in these studies. Mechanistically, the immunomodulatory properties of the sympathetic nervous system have been highlighted. Furthermore, we explore the immunotherapeutic benefits of acupuncture in treating sepsis. A better understanding of the immunoregulatory mechanism of sympathetic nervous system may offer novel approaches for the development of therapeutics to treat or prevent a variety of inflammatory diseases. [ABSTRACT FROM AUTHOR]

Hyperventilation induces metabolic changes that can elicit nystagmus (hyperventilation-induced nystagmus, HVIN) in various vestibular disorders, revealing vestibular imbalance and bringing out central or peripheral asymmetries. In acute unilateral vestibulopathy (AUVP, namely vestibular neuritis), hyperventilation can induce different patterns of nystagmus (excitatory, inhibitory, or negative), disclosing or modifying existing static vestibular asymmetries through its ability to invalidate compensation or increase peripheral excitability. In this context, we followed the evolutionary stages of HVIN in AUVP across 35 consecutive patients, with the goal of assessing alterations in the oculomotor pattern caused by hyperventilation over time. In the acute phase, the incidence of the excitatory pattern (and the strongly excitatory one, consisting of a reversal nystagmus evoked by hyperventilation) was significantly higher compared to the inhibitory pattern; then, a progressive reduction in the incidence of the excitatory pattern and a concomitant gradual increase in the incidence of the inhibitory one were observed in the follow-up period. Assuming the role of the ephaptic effect and the transient loss of vestibular compensation as opposing mechanisms, i.e., excitatory and inhibitory, respectively, the oculomotor pattern evoked by hyperventilation is the result of the interaction of these two factors. The data obtained allowed us to hypothesize an interpretative model regarding the pathogenetic aspects of responses evoked by hyperventilation and the etiologies of the disease: according to our hypotheses, the excitatory pattern implies a neuritic (viral) form of AUVP; instead, the inhibitory (and negative) one can be an expression of both the neuritic (viral) and vascular forms of the disease. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is a neurodegenerative disease that affects the central nervous system (CNS) generating neuropathic pain and anxiety. Primary progressive MS (PPMS) is the most disabling clinical form, and the patients present an intense neurodegenerative process. In this context, the advanced oxidation protein products (AOPPs) are oxidized compounds and their accumulation in plasma has been related to clinical disability in MS patients. However, the involvement of AOPPs in neuropathic pain‐ and anxiety‐like symptoms was not previously evaluated. To assess this, female mice C57BL/6J were used to induce progressive experimental autoimmune encephalomyelitis (PMS‐EAE). Clinical score, weight, strength of plantar pressure, rotarod test, mechanical allodynia, and cold hypersensitivity were evaluated before induction (baseline) and on days 7th, 10th, and 14th post‐immunization. We assessed nest building, open field, and elevated plus‐maze tests 13 days post‐immunization. Animals were killed at 14 days post‐immunization; then, AOPPs levels, NADPH oxidase, and myeloperoxidase (MPO) activity were measured in the prefrontal cortex, hippocampus, and spinal cord samples. The clinical score increased 14th post‐immunization without changes in weight and mobility. Reduced paw strength, mechanical allodynia, and cold allodynia increased in the PMS‐EAE animals. PMS‐EAE mice showed spontaneous nociception and anxiety‐like behavior. AOPPs concentration, NADPH oxidase, and MPO activity increase in CNS structures. Multivariate analyses indicated that the rise of AOPPs levels, NADPH oxidase, and MPO activity influenced the clinical score and cold allodynia. Thus, we indicated the association between non‐stimuli painful perception, anxiety‐like, and CNS oxidative damage in the PMS‐EAE model. [ABSTRACT FROM AUTHOR]

In patients presenting in the emergency department with acute vertigo, a rapid and accurate differential diagnosis is crucial, as posterior circulation strokes can mimic acute vestibular losses, leading to inappropriate treatment. The diagnosis of vestibular neuritis is made based on the clinical manifestation and a bedside otoneurological assessment. In the clinical examination, an evaluation of the vestibulo-ocular reflex is the key element; however, the accuracy of the bedside head impulse test depends on the clinician's experience. Thus, new diagnostic methods are needed to objectify and facilitate such rapid vestibular evaluations. The aim of our paper is to provide a comprehensive review of the video head impulse test's application in the diagnosis of vestibular neuritis. Numerous studies have reported advantages that make this method helpful in detailed otoneurological evaluations; in contrast to the bedside head impulse test, it enables an analysis of all six semicircular canals function and records the covert corrective saccades, which are invisible to the naked eye. As a portable and easy diagnostic tool, it is known to improve the diagnostic accuracy in patients with acute vertigo presenting in the emergency department. Moreover, as it evaluates the vestibulo-ocular reflex across different frequencies, as compared to caloric tests, it can be used as an additional test that is complementary to videonystagmography. Recently, several papers have described the application of the video head impulse test in follow-up and recovery evaluations in patients with vestibular neuritis. [ABSTRACT FROM AUTHOR]

To evaluate the potential impact of coronavirus disease 2019 (COVID-19) and vaccinations on otologic diseases, including facial nerve paralysis (including Ramsay Hunt syndrome), vestibular neuritis, sudden sensorineural hearing loss, and Meniere's disease. In this retrospective study, we conducted a time-series analysis employing a causal impact algorithm on a large-scale inpatient database in Japan. We compared the actual number of hospitalized patients with otologic diseases to two predictions: one without any covariates and another with a covariate accounting for the reduction in the number of hospitalized patients due to lockdown measures. Additionally, we performed Granger causality tests to ensure the robustness of our findings. No significant increase was noted in the number of hospitalized patients with otologic diseases following the onset of the COVID-19 pandemic in the causal impact analysis. Similarly, no notable surge was observed in hospitalizations for these diseases following the introduction of the COVID-19 vaccine. The Granger causality tests results aligned with the causal impact analysis findings. Our findings indicate that COVID-19 and vaccinations had minimal discernible effects on hospitalization of patients with otologic diseases, suggesting that otologic diseases may not be significantly impacted by COVID-19 and vaccinations, which could have implications for public health policies and the allocation of healthcare resources during a pandemic. Further research and monitoring of long-term effects are warranted to validate these findings and guide healthcare decision-making. [ABSTRACT FROM AUTHOR]

Predicting prognosis after nerve injury and compression can be challenging, even for the experienced clinician. Although thorough clinical assessment can aid diagnosis, we cannot always be precise about long-term functional recovery of either motor or sensory nerves. To evaluate the severity of nerve injury, surgical exploration remains the gold standard, particularly after iatrogenic injury and major nerve injury from trauma, such as brachial plexus injury. Recently, advances in imaging techniques (ultrasound, magnetic resonance imaging [MRI] and MR neurography) along with multimodality assessment, including electrodiagnostic testing, have allowed us to have a better preoperative understanding of nerve continuity and prediction of nerve health and possible recovery. This article outlines the current and potential roles for clinical assessment, exploratory surgery, electrodiagnostic testing ultrasound and MRI in entrapment neuropathies, inflammatory neuritis and trauma. Emphasis is placed on those modalities that are improving in diagnostic accuracy of nerve assessment before any surgical intervention. [ABSTRACT FROM AUTHOR]

This article presents a study on optic neuritis (ON) induced by COVID-19, a condition characterized by inflammation of the optic nerve. The study included 13 hospitalized patients who experienced vision loss after a mild COVID-19 infection. The patients had an initial attack of ON but did not experience a relapse. The study found that involvement of certain segments of the optic nerve was associated with better visual recovery. Treatment with corticosteroids and plasmapheresis improved visual acuity and prognosis for most patients. However, the study had limitations due to a small sample size and short follow-up period, and further research is needed to confirm the significance of certain antibodies in these patients. [Extracted from the article]

BACKGROUND: There is a lack of comparative studies examining changes in vestibulo-ocular reflex (VOR) gain with head velocity in the video head impulse test (vHIT) of patients with vestibular neuritis (VN). Thus, the purpose of present study was to identify the effect of head impulse velocity on the gain of the VOR during the vHIT in patients with VN. METHODS: Head impulse velocities ranging from 100%-200°/s [158.08 ± 23.00°/s in the horizontal canal (HC), 124.88 ± 14.80°/s in the anterior canal (AC), and 122.92 ± 14.26°/s in the posterior canal (PC) were used during vHIT trials of 32 patients with VN. Differences in VOR gain on the ipsilesional and contralesional sides according to head velocity were analyzed. RESULTS: The mean VOR gains in ipsilesional side were decreased to 0.47 in the HC and 0.56 in the AC, leading to marked asymmetry compared to the contralesional side; PC gain was relatively preserved at 0.82 in the ipsilesional side. The mean head impulse velocity applied during vHIT trials in each semicircular canal plane did not differ bilaterally. On the contralesional side, VOR gain was negatively correlated with head impulse velocity (R²=0.25, P=.004 in HC; R²=0.17, P=.021 in AC; R²=0.24, P=.005 in PC), while VOR gain on the ipsilesional sides of the HC and AC was not. CONCLUSION: Head impulse velocity may have a differential impact on VOR gain, depending on the degree of deficit. Increasing head velocity in vHIT may be considered to identify subtle deficits on the contralesional side of patients with VN. [ABSTRACT FROM AUTHOR]

Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy is a recently emerging autoimmune disease of the central nervous system (CNS); GFAP astrocytopathy is characterized by optic neuritis and meningoencephalomyelitis. We report the case of a 55-year-old man, otherwise healthy, who presented with isolated headaches for three months, without other features of meningoencephalitis or myelitis. His neurological examination and fundoscopy were unremarkable. Gadolinium-enhanced brain MRI demonstrated increased T2 hyperintensity within the right sub-lenticular basal ganglia, with additional leptomeningeal enhancement along the bilateral perisylvian regions and mesial temporal lobes. Cerebrospinal fluid (CSF) analysis showed lymphocytic pleocytosis, elevated protein, matching oligoclonal bands, and a negative infectious and cytological workup. Cell-based assays for anti-aquaporin-4, anti-myelin oligodendrocyte glycoprotein, autoimmune encephalitis panel, and vasculitis workup were all negative, except for CSF positivity for GFAP α antibody. Oncological screening, including CT of the chest, abdomen, pelvis, and scrotal US, was unremarkable. Immunotherapy with high-dose intravenous steroids for five days and subsequent single four-weekly doses resulted in the resolution of both clinical and radiographic features, with a maintained status 24 months after onset. This case highlights isolated headache and basal ganglia, mesial temporal lobe involvement as a rare presentation of autoimmune GFAP astrocytopathy. [ABSTRACT FROM AUTHOR]

We describe Magnetic Resonance Imaging (MRI) findings in a 49-years-old female who presented with subacute visual loss. MRI findings were suggestive of optic neuritis and chiasmal neuritis. She had necrotic mediastinal lymphadenopathy which was diagnosed as tuberculosis. Optic neuritis and chiasmal neuritis in this case were most probably due to hypersensitivity to mycobacterium. To the best of authors' knowledge, these unusual MRI findings of optic and chiasmal neuritis caused by hypersensitivity to mycobacterium have not been previously reported. [ABSTRACT FROM AUTHOR]

Background and Aim: Several laboratory tools are used to evaluate balance disorders but, there is still no screening test to determine the site and the severity of the lesion. The aim was to investigate whether video Head Impulse Test (vHIT) can be used as a screening test in patients with chronic or recurrent vertigo and dizziness. Methods: The files of 965 patients who were followed up in our vertigo outpatient clinic were reviewed retrospectively. Vestibulo-Ocular Reflex (VOR) gains and saccadic movements of the right and left lateral canals in the vHIT test, and Canal Paresis (CP) in the Caloric Testing (CT) were noted. Results: A total of 325 patients were included in our study. In CT results, the group that CP was most frequently detected was Menière's Disease (MD) group (71 patients (74.7%). While vHIT results were found to be pathological in the vast majority of patients in the Vestibular Neuritis (VN) group (72.7%), the results were found to be normal at the highest rate in the vestibular migraine group (77.9%). Correlation analysis showed a significant but weak correlation between the degree of CP in the CT and the VOR gains of the lateral canals in vHIT in all groups. Conclusion: Although it has high sensitivity in cases with VN and vestibulopathy, we think that vHIT cannot be used as a screening tool in patients with vertigo, especially for chronic cases, since its sensitivity rate differs in the long term according to the cause of the disease. [ABSTRACT FROM AUTHOR]

Introduction and objective: Within acute and episodic childhood vertigos, those secondary to trauma, otitis media, neuritis/labyrinthitis, perilymphatic fistula, Ménière's disease, vestibular paroxysmia, benign paroxysmal positional vertigo and bilateral vestibulopathy account for around 10% of all cases of infant vestibular disorders. Diagnosis must be early accomplished based on the defining criteria, although in children there are other accessory criteria that should be considered (behavioral changes, digestive, etc...). The treatment should achieve prompt symptomatic resolution of the crises, prevention or reduction of recurrences, minimization and palliation of sequelae and maximum normalization of daily life and activities. Objective: To carry out a brief and practical review on the symptoms, the diagnostic criteria and the treatment of infantile vertigo in the previously mentioned topics. Method: Narrative review using PubMed, Fisterra, ClinicalKey and Google Scholar. Results: Citations were obtained, of which non-significant ones were discarded due to their general nature, age, non-relevance according to the authors' criteria, or non-availability in English or Spanish. A total of 60 articles were considered for this review. Discussion: Narrative review on the topics described. Conclusions: The diagnostic criteria and treatment for the topics proposed in this chapter are defined for adults; however, in children, we must consider accessory criteria for a prompt diagnosis. The treatment is conditioned by age and is based on several pillars (pharmacological, lifestyle, rehabilitation and psychological). The prognosis, in general, is better than that of adults due to childhood neural plasticity. [ABSTRACT FROM AUTHOR]