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The growing interest in wearable and portable devices has stimulated the need for flexible and stretchable lithium-ion batteries (LiBs). A crucial component in these batteries is the separator, which provides a pathway for Li-ion transfer and prevents electrode contact. In a flexible and stretchable LiB, the separator must exhibit stretchability and elasticity akin to its existing counterparts. Here, we developed a non-modified thermoplastic polyurethane (TPU) separator using the non-solvent induced phase separation (NIPS) technique. We compared their performance with commercially available polypropylene (PP) separators. Our results demonstrate that TPU separators exhibit superior elasticity based on repeated stretch/release tests with excellent thermal stability and electrolyte wettability. Furthermore, our findings confirm that TPU separators, even after being repeatedly stretched and released, can function effectively without severe damage in a fabricated coin cell LiB with high oxidative stability, as evidenced by linear sweep voltammetry, like commercially available separators. [ABSTRACT FROM AUTHOR]

Background and purpose: Tolosa-Hunt Syndrome (THS) is a rare disorder, and detailed clinical information and treatment outcomes have yet to be fully elucidated. This study aims to investigate the clinical features and factors associated with the treatment outcomes of THS, as defined by the established diagnostic criteria. Methods: This study retrospectively recruited 91 patients with a diagnosis of THS from 2003 to 2020. We analyzed the clinical features and outcomes, the initial treatment response, recurrences, and the final treatment response. Results: Isolated ocular motor nerve palsy was the most common (82.4%) finding of ophthalmoplegia, involving the oculomotor nerve in more than half of the cases (52.0%). The MRI lesions were mostly observed in the cavernous sinus (94.5%) with an extracavernous extension in about one-third of them. Five patients showed only extracavernous lesions. A total of 25 (27.5%) patients experienced recurrence. Recurrence occurred during steroid tapering as part of the initial treatment in seven, while in 18 patients, it happened after the successful termination of the initial treatment. However, all patients achieved complete remission at the final. Age was associated with a decrease in initial symptom duration (HR = 1.023, CI = 1.004–1.044) as well as an increase in recurrence-free duration (HR = 0.944, CI = 0.911–0.978). High-dose corticosteroid treatment was associated with a decrease in initial symptom duration (HR = 1.642, CI = 1.001–2.695) and total treatment duration (HR = 2.203 CI = 1.302–3.730). Conclusions: THS can recur frequently especially in younger but have a favorable prognosis. High-dose corticosteroids can be an effective initial treatment and reduce the total treatment duration. [ABSTRACT FROM AUTHOR]

The results of video head impulse tests (video-HITs) may be confounded by data artifacts of various origins, including pupil size and eyelid obstruction of the pupil. This study aimed to determine the effect of these factors on the results of video-HITs. We simulated ptosis by adopting pharmacological dilatation of the pupil in 21 healthy participants (11 women; age 24–58 years). Each participant underwent video-HITs before and after pupillary dilatation using 0.5% tropicamide. We assessed the changes in the vestibulo-ocular reflex (VOR) gain, corrective saccade amplitude, and frequency of eyelid flicks. After pupillary dilatation, the VOR gain decreased for both right (RAC; 1.12 ± 0.12 vs. 1.01 ± 0.16, p = 0.011) and left anterior canals (LACs; 1.15 ± 0.13 vs. 0.96 ± 0.14, p < 0.001), and right posterior canal (RPC, 1.10 ± 0.13 vs. 0.98 ± 0.09, p = 0.001). The corrective saccade amplitudes also decreased significantly for all four vertical canals. The frequency of eyelid flicks, however, did not change. The changes of VOR gain were positively correlated with the lid excursion in RPC (r = 0.629, p = 0.002) and LPC (r = 0.549, p = 0.010). Our study indicates that eyelid position and pupil size should be considered when interpreting the results of video-HITs, especially for the vertical canals. Pupils should be shrunk in a very well-lit room, and artifacts should be prevented by taping or lifting the eyelids as required during video-HITs. [ABSTRACT FROM AUTHOR]

Benign paroxysmal positional vertigo (BPPV) is the most common cause of vertigo worldwide. This review considers recent advances in the diagnosis and management of BPPV including the use of web-based technology and artificial intelligence as well as the evidence supporting the use of vitamin D supplements for patients with BPPV and subnormal serum vitamin D. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pressure-sensitive adhesive (PSA) exhibiting robust underwater adhesion was developed through the synergistic integration of gallol-functionalization and microscale surface patterning. • Gallol group introduction in a smaller proportion (3.3 mol%) demonstrated more than double the underwater adhesion strength compared to the benzyl (4.3 mol%) or phenol (3.6 mol%) groups. • Surface patterning reduced adhesion loss in water from 62% to 11%. • The pattern on the PSA surface generated drainage channels, effectively reducing defect size and ensuring a uniform distribution of adhesion defects. In this study, we synthesized a gallol-functionalized PSA and generated micropatterns on its surface to improve its underwater adhesion. Compared to the adhesive-substrate interactions of benzyl and phenol-functionalized PSAs in water, Gallol PSA exhibited greater interactions with the substrate. Furthermore, the micropattern on the PSA surface provided a drainage channel for water during the bonding process so that water is not trapped at the substrate-adhesive interface. Moreover, the drainage channel allows the formation of small and uniform adhesion defects, which minimize the deterioration in adhesion caused by water. And the adhesive manufacturing process is also simple, without any gallol protection and deprotection steps, and can be achieved using the current adhesive industry infrastructure. This facile fabrication strategy and its adhesive properties could promote the commercialization of gallol-functionalized PSAs with underwater adhesion. [ABSTRACT FROM AUTHOR]

Thus, the preferential saccadic impairments and truncal ataxia observed in our patient may corroborate the cerebellar midline lesion observed in most patients. Indeed, metronidazole-associated peripheral neuropathy is found in one-third of patients with metronidazole CNS toxicity [[1]]. C Fluid-attenuated inversion recovery (FLAIR) images show high-signal-intensity lesions involving the dentate nuclei (yellow arrows), superior colliculi (yellow arrowheads), and splenium of the corpus callosum. Notably, a characteristic reversible dentate nuclei lesion is found in 90% of patients [[1], [4]]. [Extracted from the article]

The material extrusion (ME) process is one of the most widely used 3D printing processes, especially considering its use of inexpensive materials. However, the error known as the "spaghetti-shape error," related to filament tangling, is a common problem associated with the ME process. Once occurring, this issue, which consumes both time and materials, requires a restart of the entire process. In order to prevent this, the user must constantly monitor the process. In this research, a failure detection method which uses a webcam and deep learning is developed for the ME process. The webcam captures images and then analyzes them by machine learning based on a convolutional neural network (CNN), showing outstanding performance in both image classification and the recognition of objects. Sample images were trained based on a modified Visual Geometry Group Network (VGGNet) model and the trained model was evaluated, resulting in 97% accuracy. The pre-trained model was tested on a 3D printer monitoring system for its ability to recognize the "spaghetti-shape-error" and was able to detect 96% of abnormal deposition processes. The proposed method can analyze the ME process in real time and informs the user or halts the process when abnormal printing is detected. [ABSTRACT FROM AUTHOR]

This document, titled "Ocular Flutter Evoked by Vestibular Stimulation," discusses a case study of a 26-year-old woman who experienced ocular flutter, a condition characterized by spontaneous bursts of eye movements, exclusively during head motion and vestibular stimulation. The patient presented with oscillopsia (the perception of objects moving) and other symptoms such as clumsiness and headache. Various tests and examinations were conducted, including video-oculography, which revealed the presence of ocular flutter during specific stimuli. The authors propose several mechanisms that may explain the occurrence of ocular flutter in this case, involving the interaction between the vestibular and saccadic systems. The patient's symptoms improved after receiving treatment with intravenous immunoglobulin and methylprednisolone. The study suggests that vestibular stimulation may play a role in generating ocular flutter. [Extracted from the article]

Background: Although there are various techniques of thread lifting, most of these techniques require anchoring of the threads at the temple area. However, the frontal branch of the superficial temporal artery (FBrSTA) is located in the temple area and a detour pathway should be created for thread insertion to avoid vascular complications. Objectives: We aimed to determine the relationship between the FBrSTA and the hairline using real‐time Doppler ultrasound. Methods: Doppler ultrasound was used to detect the FBrSTA pathway, and the relationship between the hairline and the FBrSTA was analyzed. After confirming the arterial pathway, thread lifting was performed in patients, and complications related to the entry point and insertion of the threads were evaluated. Patient satisfaction was evaluated immediately after the procedure and 3 months later. Results: This study included 50 patients (45 women and 5 men; age: 51 [range 26‐71] years) who underwent thread lifting in a single institution from January to May 2019 after Doppler ultrasound‐guided detection of the FBrSTA. No vascular complications were noted in all patients. Conclusions: Our findings suggest that Doppler ultrasound can be used to detect the FBrSTA at the temple area to avoid vascular complications during thread lifting. [ABSTRACT FROM AUTHOR]

Isolated dizziness and vertigo due to vascular mechanisms are frequently misdiagnosed as peripheral vestibulopathy or vestibular migraine. For diagnosis of strokes presenting with an acute prolonged (≥ 24 hours) vestibular syndrome, findings on clinical examination, such as HINTS (negative head impulse tests, detection of direction-changing gaze-evoked nystagmus, and presence of skew deviation), are more sensitive than findings on neuroimaging. Since HINTS alone cannot securely detect anterior inferior cerebellar artery strokes, additional attention should be paid to the patients with unexplained hearing loss in addition to acute prolonged vestibulopathy. For diagnosis of transient (< 24 hours) spontaneous vestibular syndrome due to vascular mechanisms, the presence of associated craniocervical pain and focal neurological symptoms/signs is the clue. Even without these symptoms or signs, however, vascular imaging combined with perfusion- and diffusion-weighted MRI should be performed in patients with multiple vascular risk factors or a high ABCD2 score (age, blood pressure, clinical features, duration of symptom, and presence of diabetes). [ABSTRACT FROM AUTHOR]

Bilateral vestibular dysfunction (BVD) refers to hypofunction of the vestibular nerves or labyrinths on both sides. Patients with BVD present with dizziness, oscillopsia, and unsteadiness, mostly during locomotion, which worsen in darkness or on uneven ground. Although aminoglycoside ototoxicity, Meniere's disease, infection, and genetic disorders frequently cause BVD, the etiology remains undetermined in up to 50% of the patients. The diagnosis of BVD requires both symptoms and documentation of deficient vestibulo-ocular reflex function using head-impulse, bithermal caloric, and rotatory chair tests. Since various neurologic and systemic disorders may present with BVD, clinicians should be cautious not to overlook the symptoms and signs of central nervous system and systemic involvements. Vestibular rehabilitation, application of vibrotactile and auditory feedbacks, and vestibular prosthesis can aid the patients with BVD along with the correction of the underlying causes. [ABSTRACT FROM AUTHOR]

Cerebellar nodulus and uvula and their connections with the vestibular nuclei form the so‐called velocity‐storage circuit. Lesions involving the velocity‐storage circuit give rise to positional vertigo and nystagmus. Herein, we present a 32‐year‐old man with cerebellar nodulus and uvular hemorrhage who showed periodic vertigo and downbeat nystagmus in the supine position. To explain this unusual pattern, we adopted velocity‐storage model with a lesion on the neural connection between the gravity and inertia estimators, resulting in periodic neural impulses and a gravity bias in a specific position. This report expands the spectrum of central positional nystagmus due to dysfunction of the velocity‐storage mechanism. [ABSTRACT FROM AUTHOR]

The association between changes in alcohol consumption and body composition remains unclear. We investigated the association between changes in drinking habits and muscle mass and fat mass in adults. From the Health Examinees in Korea, the study population (N = 62 094) was categorized according to alcohol consumption (g of ethanol/day) and the changes in drinking habits between the baseline and follow-up periods were determined. Predicted muscle mass index (pMM), lean mass index, and fat mass index (pFM) were also calculated using age, sex, weight, height, and waist circumference. The β coefficient and adjusted means were then calculated using multiple linear regression analysis after adjusting for covariates, including follow-up duration, calorie intake, and protein intake. Compared to the almost-unchanged drinking group (reference; adjusted mean: −0.030 [95% confidence intervals: −0.048, −0.011]), there was no statistical difference or tendency of change in the pMMs of the most-decreased (−0.024 [−0.048, 0.000]) and the most-increased (−0.027 [−0.059, −0.013]) alcohol-consumed groups. The pFM decreased at those with less alcohol consumption (0.053 [−0.011, 0.119]) and increased with increased alcohol consumption (0.125 [0.063, 0.187]), compared to the no-change group (reference; 0.088 [0.036, 0.140]). Thus, changes in alcohol consumption were not significantly associated with changes in muscle mass. Increased alcohol consumption was associated with increased fat mass. Reducing the amount of alcohol consumption may improve body composition in terms of fat mass. • The amount of alcohol consumption (g of ethanol/days) and body composition (kg/m2) were calculated, based on the survey of health habit and anthropometric data in the individual. • Alcohol consumption was not significantly associated with muscle mass. • However, increased alcohol consumption was associated with increased fat mass. [ABSTRACT FROM AUTHOR]

Purpose: To delineate the association between otolith function and changes in mean orthostatic blood pressure (BP) and heart rate (HR) in patients with postural orthostatic tachycardia syndrome (POTS). Methods: Forty-nine patients with POTS were prospectively recruited. We analyzed the results of ocular vestibular-evoked myogenic potentials (oVEMPs) and cervical vestibular-evoked myogenic potentials (cVEMPs), as well as head-up tilt table tests using a Finometer. The oVEMP and cVEMP responses were obtained using tapping stimuli and 110 dB tone-burst sounds, respectively. We measured maximal changes in 5-s averaged systolic BP (SBP), diastolic BP (DBP), and heart rate (HR) within 15 s and during 10 min after tilting. We compared the results with those of 20 age- and sex-matched healthy participants. Results: The n1–p1 amplitude of oVEMPs was larger in patients with POTS than in healthy participants (p = 0.001), whereas the n1 latency (p = 0.280) and interaural difference (p = 0.199) did not differ between the two. The n1–p1 amplitude was a positive predictor for POTS (odds ratio 1.07, 95% confidence interval 1.01–1.13, p = 0.025). Body weight (p = 0.007) and n1–p1 amplitude of oVEMP (p = 0.019) were positive predictors for ΔSBP15s in POTS, whereas aging was a negative predictor (p = 0.005). These findings were not observed in healthy participants. Conclusions: Augmented utricular inputs may be associated with a relative predominance of sympathetic over vagal control of BP and HR, especially for an early response during orthostasis in patients with POTS. Overt sympathoexcitation due to exaggerated utricular input and lack of readaptation may be associated with the pathomechanism of POTS. [ABSTRACT FROM AUTHOR]

Background and Purpose: The etiologies of abducens nerve palsy have shown a large variability among studies. This study aimed to establish the clinical features and underlying etiologies of isolated abducens nerve palsy by recruiting patients from all departments in a referral‐based university hospital. Methods: We reviewed the medical records of 807 patients with a confirmed diagnosis of isolated abducens nerve palsy at all departments of Seoul National University Bundang Hospital, Seongnam, Republic of Korea, from 2003 to 2020. We also compared the proportion of etiology with that of the patients pooled from the previous studies. Results: The most common etiology was microvascular (n = 296, 36.7%), followed by idiopathic (n = 143, 17.7%), neoplastic (n = 115, 14.3%), vascular anomalies (n = 82, 10.2%), inflammatory (n = 76, 9.4%), and traumatic (n = 35, 4.3%). Patients were mostly managed by ophthalmologists (n = 576, 71.4%), followed by neurologists (n = 479, 59.4%), emergency physicians (n = 278, 34.4%), neurosurgeons (n = 191, 23.7%), and others (n = 72, 8.9%). The proportion of etiology significantly differed according to the age and sex of the patients and the specialties involved in the management (p < 0.001). Compared to the pooled data from the previous reports, the current study showed a higher prevalence of microvascular cause but a lower occurrence of traumatic and neoplastic causes. Conclusions: The results of previous studies on etiologic distribution of isolated abducens nerve palsy should be interpreted with consideration of the demographic features of patients recruited and the specialties involved. [ABSTRACT FROM AUTHOR]

The mechanism of perverted vertical responses during horizontal head impulse tests (HITs) requires further elucidation. A 47-year-old woman with a Chiari malformation showed alternating skew deviation, downbeat nystagmus with an increasing slow phase velocity, impaired smooth pursuit, and upward ocular deviation during horizontal HITs and corrective downward saccades in the presence of normal bithermal caloric tests and intact tilt suppressions of the post-rotatory nystagmus. These findings suggest dysfunction of the inferior cerebellum including the tonsil, nodulus, and uvula. We propose that disruption of signals from the medial part of the vestibulocerebellum, which normally inhibits the lateral and anterior canal pathways, may elicit an upward misdirection of the eye velocity during rapid horizontal head rotation. Otherwise, the Chiari malformation may have directly affected the brainstem structures involved in the direction matrix of the vestibulo-ocular reflex. [ABSTRACT FROM AUTHOR]

Purpose: Möbius syndrome is characterized by abducens and facial nerve palsy. However, the presence/absence of corresponding cranial nerves on MRI was not fully evaluated. The purpose of this study was to investigate the mechanism of Möbius syndrome by associating the presence of abducens and facial nerves on MR imagings with clinical features.Methods: We retrospectively reviewed the medical records and MR imagings of nine patients with Möbius syndrome between January 2004 and October 2015. The presence/absence of abducens and facial nerves on MR imaging, as well as corresponding neuro-ophthalmologic clinical features, was investigated.Results: Facial palsy was bilateral in six and unilateral in three patients. Abduction was limited bilaterally in five and unilaterally in four patients. The degrees of facial palsy and abduction limitation were variable, and asymmetric even in the bilateral cases. MR imaging documented bilateral absence of the abducens and facial nerves in six, absence of unilateral facial nerve and bilateral abducens nerves in one, and absence of facial and abducens nerves unilaterally on the same side in another. Both abducens and facial nerves were visualized bilaterally only in the one remaining patient.Conclusions: The absence of abducens and facial nerves on MR imaging was mostly correlated with the findings of facial palsy and abduction limitation in patients with Möbius syndrome. MR imaging aids in diagnosis of Möbius syndrome by documenting the absence or presence of abducens and facial nerves. [ABSTRACT FROM AUTHOR]

Abstract: This study used resting state functional magnetic resonance imaging (rsfMRI) to investigate whole brain networks in patients with persistent postural perceptual dizziness (PPPD). We compared rsfMRI data from 38 patients with PPPD and 38 healthy controls using whole brain and region of interest analyses. We examined correlations among connectivity and clinical variables and tested the ability of a machine learning algorithm to classify subjects using rsfMRI results. Patients with PPPD showed: (a) increased connectivity of subcallosal cortex with left superior lateral occipital cortex and left middle frontal gyrus, (b) decreased connectivity of left hippocampus with bilateral central opercular cortices, left posterior opercular cortex, right insular cortex and cerebellum, and (c) decreased connectivity between right nucleus accumbens and anterior left temporal fusiform cortex. After controlling for anxiety and depression as covariates, patients with PPPD still showed decreased connectivity between left hippocampus and right inferior frontal gyrus, bilateral temporal lobes, bilateral insular cortices, bilateral central opercular cortex, left parietal opercular cortex, bilateral occipital lobes and cerebellum (bilateral lobules VI and V, and left I–IV). Dizziness handicap, anxiety, and depression correlated with connectivity in clinically meaningful brain regions. The machine learning algorithm correctly classified patients and controls with a sensitivity of 78.4%, specificity of 76.9%, and area under the curve = 0.88 using 11 connectivity parameters. Patients with PPPD showed reduced connectivity among the areas involved in multisensory vestibular processing and spatial cognition, but increased connectivity in networks linking visual and emotional processing. Connectivity patterns may become an imaging biomarker of PPPD. [ABSTRACT FROM AUTHOR]

To improve the applicability of quercetin (QCT), we produced a QCT and cycloamylose (CA-QCT) inclusion complex based on the cyclization activity of cyclodextrin glucanotransferase (CGTase; EC 2.4.1.19). The encapsulated QCT was purified using recycling preparative high-performance liquid chromatography, and its formation was analyzed using matrix-assisted laser desorption/ionization-time of flight mass spectrometry. The water solubility of CA-QCT was 55,000-fold higher than that of QCT. CA-QCT had 97 % stability for one week at pH 8 in a 4 °C water bath. According to a 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity assay, CA-QCT activity in aqueous solution was 24 times higher than that of an equal amount of QCT in aqueous solution. In an anti-inflammatory assay using lipopolysaccharide-induced RAW264.7 macrophages, CA-QCT in aqueous solution decreased nitric oxide production in a similar manner to QCT in dimethyl sulfoxide (DMSO). Additionally, even under aqueous conditions, CA-QCT more effectively inhibited the production of inflammatory mediators, such as interleukin-1β, interleukin-6, and cyclooxygenase, compared with QCT dissolved in DMSO. [Display omitted] [ABSTRACT FROM AUTHOR]

Background and purpose: The temporal characteristics of stroke risks were evaluated in emergency department patients who had a diagnosis of peripheral vertigo. It was also attempted to reveal the stroke risk factor amongst those with peripheral vertigo. Methods: This is a parallel‐group cohort study in a tertiary referral hospital. After assigning each of 4367 matched patients to the comparative set of peripheral vertigo and appendicitis‐ureterolithiasis groups and each of 4911 matched patients to the comparative set of peripheral vertigo and ischaemic stroke groups, the relative stroke risk was evaluated. In addition, to predict the individual stroke risk in patients with peripheral vertigo, any association between the demographic factors and stroke events was evaluated in the peripheral vertigo group. Results: The peripheral vertigo group had a higher stroke risk than the appendicitis‐ureterolithiasis group (hazard ratio 1.73, 95% confidence interval 1.18–2.55) but a lower risk than the ischaemic stroke group (hazard ratio 0.30, 95% confidence interval 0.24–0.37). The stroke risk of the peripheral vertigo group was just below that of small vessel stroke. The stroke risk of the peripheral vertigo group differed markedly by time: higher within 7 days, moderate between 7 days and 1 year, and diminished thereafter. Old age (>65 years), male gender and diabetes mellitus were the risk factors for stroke in the peripheral vertigo group. Conclusion: Patients with a diagnosis of peripheral vertigo in the emergency department showed a moderate future stroke risk and so a stroke preventive strategy tailored to the timing of symptom onset and individual risk is required. [ABSTRACT FROM AUTHOR]

Background: Spatiotemporal regulation is one of the major considerations for developing a controlled and targeted drug delivery system to treat diseases efficiently. Light-responsive plasmonic nanostructures take advantage due to their tunable optical and photothermal properties by changing size, shape, and spatial arrangement. Results: In this study, self-integrated plasmonic hybrid nanogels (PHNs) are developed for spatiotemporally controllable drug delivery through light-driven conformational change and photothermally-boosted endosomal escape. PHNs are easily synthesized through the simultaneous integration of gold nanoparticles (GNPs), thermo-responsive poly (N-isopropyl acrylamide), and linker molecules during polymerization. Wave-optic simulations reveal that the size of the PHNs and the density of the integrated GNPs are crucial factors in modulating photothermal conversion. Several linkers with varying molecular weights are inserted for the optimal PHNs, and the alginate-linked PHN (A-PHN) achieves more than twofold enhanced heat conversion compared with others. Since light-mediated conformational changes occur transiently, drug delivery is achieved in a spatiotemporally controlled manner. Furthermore, light-induced heat generation from cellular internalized A-PHNs enables pinpoint cytosolic delivery through the endosomal rupture. Finally, the deeper penetration for the enhanced delivery efficiency by A-PHNs is validated using multicellular spheroid. Conclusion: This study offers a strategy for synthesizing light-responsive nanocarriers and an in-depth understanding of light-modulated site-specific drug delivery. [ABSTRACT FROM AUTHOR]

Background and objectives: As the efficacy of current diagnostic methods for myasthenia gravis (MG) remains suboptimal, there is ongoing interest in developing more effective diagnostic models. As oculomotor fatigability is one of the most common and diagnostic symptoms in MG, we aimed to investigate whether quantitative saccadic and smooth-pursuit fatigability analyses with video-oculography (VOG) are useful for diagnosis of MG. Methods: A convenience cohort of 46 MG patients was recruited prospectively, including 35 with ocular and 11 with generalized MG (mean age, 50.9 ± 14.5 years; 17 females); 24 healthy controls (HCs) (mean age, 50.6 ± 16.3 years; 13 females) also were enrolled. Seventy-five repetitive saccades and smooth pursuits were recorded in ranges of 20° (horizontal plane) and 15° (vertical plane) using a three-dimensional VOG system. Based on the oculomotor range of the second saccade and smooth pursuit and the mean ranges of the last five of each, the estimated decrements (%) reflecting oculomotor fatigability were calculated. Results: The baseline oculomotor ranges did not show significant difference between the MG and HCs groups. However, following repetitive saccades and pursuits, the oculomotor ranges were decreased substantially during the last five cycles compared to baseline in the MG group. No such decrements were observed in the HC group (p < 0.01, Mann–Whitney U test). Receiver operating characteristic (ROC) analysis revealed that repetitive vertical saccades yielded the best differentiation between the MG and HC groups, with a sensitivity of 78.3% and specificity of 95.8% when using a decrement with an amplitude of 6.4% as the cutoff. Conclusion: This study presents an objective and reproducible method for measuring decrements of oculomotor ranges after repetitive saccadic and pursuit movements. Quantification of oculomotor fatigability using VOG could be a sensitive and specific diagnostic tool for MG and allows easy, cost-effective, accurate, and non-invasive measurements. Classification of evidence: This study provides class III evidence that VOG-based quantification of saccadic and pursuit fatigability accurately identifies patients with MG. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the lateralization value of video head-impulse test (vHIT) for the diagnosis of vestibulopathy and to analyze cases showing dissociated results with caloric test.Methods: In total, 19 healthy volunteers and 92 dizzy patients who underwent both a caloric test and a vHIT were enrolled. Patients were divided into two groups depending on their fluctuating pattern of vertigo. The vestibulo-ocular reflex (VOR) gain and gain asymmetry (GA) of a vHIT as well as unilateral weakness (UW) and the sum of the slow-phase velocities (SPVs) of warm and cold irrigation of the same side were compared. A cutoff value of VOR gain of a vHIT was also calculated using a receiver-operating characteristic curve.Results: A VOR gain in an affected ear and GA of a vHIT showed a statistically significant correlation with UW in a caloric test. The cutoff value of a vHIT was determined to be 0.875, derived under the assumption that UW of a caloric test ≤25% is normal. However, the parameters of the two tests were dissociated in 18%.Conclusion: A VOR gain of vHIT is a valuable objective parameter with a lateralization value determining vestibular hypofunction. However, considering substantial dissociation between a vHIT and a caloric test, these tests can be complementary tools for the lateralization of vestibular impairment for the comprehensive evaluation of patients' VOR. [ABSTRACT FROM AUTHOR]

Dizziness/vertigo is the most common symptoms of posterior circulation strokes. Isolated vestibular symptoms and signs without other neurologic deficits have been found in infarctions involving the brainstem and cerebellum. In the brainstem, infarctions responsible for isolated vestibular syndrome are usually restricted to the dorsal portion that contains the vestibular nucleus and the nucleus prepositus hypoglossi. Cerebellar lesions confined to the flocculus, tonsil, and nodulus also produce isolated vertigo and imbalance. The cerebellar peduncle, as a conduit between the brainstem and cerebellum, can also produce isolated vestibular syndrome when damaged. Recognition of these isolated central vestibular syndromes aids in defining the function of each structure and in localizing the involved neural structures based upon the vestibular and ocular motor findings. [ABSTRACT FROM AUTHOR]

A synthesis strategy to obtain hierarchically porous N-doped carbon (P–N–C) nanofibers (NFs) comprising VN nanodots and highly densified-entangled N-doped CNTs (N-CNTs) was visualized. The unique redox-active nanostructure was applied as a multifunctional interlayer for highly stable Li–S batteries (LSBs). The P–N–C skeleton obtained via selective removal of amorphous carbon (AC) and polystyrene (PS) not only guarantees efficient electrolyte percolation but also facilitates rapid diffusion of charged species during charge-discharge processes. Moreover, the N-CNTs constituting the fiber matrix increase the overall conductivity of the framework. Besides, highly conductive vanadium nitride (VN) nanodots act as chemisorption sites for efficient lithium polysulfide capturing and prohibit their diffusion towards the anode through efficient catalytic conversion, thus improving the elemental S utilization. The Li–S cells utilizing P–N–C@VN/N-CNT NF as a multifunctional barrier resulted in decent rate capabilities (559 mA h g−1 at 2.0 C) and long-term cycling stabilities at low and high C-rates (432 mA h g−1 after the 400th cycle at 0.1 C and 290 mA h g−1 at the end of 600th cycle at 1.0 C). This is attributed to the combined synergistic effects of the P–N–C framework, N-CNT matrix, and polar VN nanodots. [Display omitted] • Hierarchically porous nitrogen-doped carbon (P–N–C) nanofibers are prepared. • Comprising VN nanodots and densified entangled N-doped CNTs (N-CNTs). • VN nanodots act as chemisorption sites for efficient anchoring of lithium polysulfide. • N-CNTs increase the overall conductivity of the nanostructure framework. • Li–S cell with P–N–C@VN/N-CNT NF-coated separator exhibits stable performance. [ABSTRACT FROM AUTHOR]

Background and objectives: Even though impaired horizontal and vertical saccades are well-known features of progressive supranuclear palsy (PSP), abnormalities of torsional quick phases of eye movements have not been defined in PSP and other Parkinsonian syndromes. This study aims to determine the diagnostic value of decreased torsional quick phases during head oscillations in the roll plane in patients with PSP. Methods: Using video-oculography, we recorded the head and eye motion during passive head oscillations in the roll plane and determined the decrease of torsional quick phases in patients with PSP (n = 13) in comparison to normal controls (n = 13) and those with multiple system atrophy (MSA, n = 17) or idiopathic Parkinson's disease (PD, n = 6). Results: Torsional quick phases were absent during the torsional vestibulo-ocular reflex (VOR) in 78.6% (11/13) of the patients with PSP, but only in 11.8% (2/17) of those with MSA and none with idiopathic PD or of normal controls (Chi-square tests, p < 0.001) while gains of the torsional VOR did not differ among the groups (Chi-square tests, p > 0.05). Furthermore, the torsional quick phases were smaller even when observed in patients with PSP. Conclusion: Loss of torsional quick phases is an early biological marker for diagnosis of PSP, and may be ascribed to degeneration of the rostral interstitial nucleus of the medial longitudinal fasciculus that contains the burst neurons for torsional as well as vertical saccades. [ABSTRACT FROM AUTHOR]

The incidence and characteristics of acute vestibular symptoms, responsible structures, and lateralization of the causative lesions in supratentorial stroke remain unknown. This study aimed to determine the incidence, clinical features, and anatomical correlation of acute vestibular symptoms in supratentorial stroke. We performed a prospective, multicenter, observational study that had recruited patients with supratentorial stroke from the neurology clinics of referral-based four university hospitals in Korea. All patients received a constructed neuro-otological evaluations, and neuroimaging. We analyzed the incidence of acute vestibular symptoms, abnormal ocular motor and vestibular function tests, and stroke lesions. Of 1301 patients with supratentorial stroke, 48 (3.7%) presented with acute vestibular symptoms, and 13 of them (1%) had the vestibular symptoms in isolation. In patients with acute vestibular symptoms, abnormal findings included spontaneous nystagmus (5%), impaired horizontal smooth pursuit (41%), and abnormal tilt of the subjective visual vertical (SVV) (20%). Video head impulse and caloric tests were normal in all the patients. There was no clear correlation between acute vestibular symptoms and involvement of specific vestibular cortex. In patients with unilateral stroke, there was also no lateralization of the causative lesions of acute vestibular symptoms (left vs. right; 52 vs. 48%), even in patients with vertigo (left vs. right; 58 vs. 42%). This study demonstrates that the incidence of acute vestibular symptoms in supratentorial stroke is 3.7%, with being isolated in 1%. The widespread lesions responsible for acute vestibular symptoms implicate diffuse multisensory cortical–subcortical networks in the cerebral hemispheres without a lateralization. [ABSTRACT FROM AUTHOR]

Background and objectives: The etiologic distribution and clinical features of diplopia may differ according to the specialties involved in the management. This study aimed to establish the clinical features and underlying etiologies of diplopia by recruiting patients from all departments. Methods: We reviewed the medical records of 4127 patients with diplopia as the chief complaint, who had been recruited from all departments at Seoul National University Bundang Hospital, Seongnam, Republic of Korea, from 2003 to 2020. Results: Diplopia was binocular in 3557 (94.2%) and monocular in 219 (5.8%) patients. The common causes of binocular diplopia included microvascular (n = 516, 14.5%), strokes (n = 412, 11.6%), neoplastic (n = 304, 8.5%), myasthenia gravis (n = 253, 7.1%), traumatic (n = 240, 6.7%), and decompensated phoria (n = 232, 6.5%), and comprised more than a half of the causes. Patients with binocular diplopia were usually managed by neurologists (2549/3557, 71.7%), followed by ophthalmologists (2247/3557, 63.2%), emergency physicians (1528/3557, 43.0%), neurosurgeons (361/3557, 10.1%), and others (271/3557, 7.6%). The etiologies of binocular diplopia differed markedly according to the patients' age and the specialties involved in the management (p < 0.001). Conclusions: Given the differences in the etiologic distribution of diplopia according to the patients' age and the specialties involved in the management, the results of previous reports on the characteristics and etiology of diplopia, primarily performed in a single specialty department, should be interpreted with a possible selection bias. [ABSTRACT FROM AUTHOR]

Ophthalmoplegia is the diagnostic hallmark of anti-GQ1b antibody syndrome. This study aimed to define the patterns of acute comitant strabismus in patients with anti-GQ1b antibody syndromes. We retrospectively analyzed the ocular motor findings in 84 patients with anti-GQ1b antibody-associated ophthalmoplegia during the acute phases. Of the 84 patients, 11 (13%) showed acute comitant strabismus. Compared to those without, patients with acute comitant strabismus frequently showed abnormal ocular motor findings that included gaze-evoked (n = 8), spontaneous (n = 4) and positional nystagmus (n = 4), saccadic hypermetria (n = 3), head-shaking nystagmus (n = 2), pulse-step mismatch (n = 1), and impaired visual cancellation of the vestibulo-ocular reflex (n = 1, p < 0.001). On the contrary, iridoplegia (p = 0.029) and ptosis (p = 0.001) were more commonly observed in patients with paralytic (incomitant) strabismus than in those with acute comitant strabismus. Comitant strabismus can manifest during the acute phase of anti-GQ1b antibody syndromes in association with other central ocular motor abnormalities. These findings implicate that the cerebellum and/or brainstem can be the primary target of the anti-GQ1b antibodies. [ABSTRACT FROM AUTHOR]

Diagnosis of combined peripheral and central vestibulopathy remains a challenge since the findings from peripheral vestibular involvements may overshadow those from central vestibular disorders or vice versa. The aim of this study was to enhance detection of these intriguing disorders by characterizing the clinical features and underlying etiologies. We had recruited 55 patients with combined peripheral and central vestibulopathy at the Dizziness Clinic of Seoul National University Bundang Hospital from 2003 to 2013. Peripheral vestibular involvement was determined by decreased caloric responses in either ear, and central vestibulopathy was diagnosed with obvious central vestibular signs or the lesions documented on MRIs to involve the central vestibular structures. Combined peripheral and central vestibulopathy could be classified into four types according to the patterns of vestibular presentation. Infarctions were the most common cause of acute unilateral cases while cerebellopontine angle tumors were mostly found in chronic unilateral ones. Wernicke encephalopathy and degenerative disorders were common in acute and chronic bilateral disorders. Twenty five (45.5%) patients showed only vestibular findings with or without auditory involvements, but association with gaze-evoked nystagmus, impaired smooth pursuit or central types of head shaking nystagmus indicated a central vestibular involvement in most of them (23/25, 92.0%). Given the requirements for urgent treatments and potentially grave prognosis of combined vestibulopathy, central signs should be sought even in patients with clinical or laboratory features of peripheral vestibulopathy. Scrutinized bedside evaluation, however, secured the diagnosis in almost all the patients with combined vestibulopathy. [ABSTRACT FROM AUTHOR]

This paper describes the diagnostic criteria for vestibular paroxysmia (VP) as defined by the Classification Committee of the Bárány Society. The diagnosis of VP is mainly based on the patient history and requires: A) at least ten attacks of spontaneous spinning or non-spinning vertigo; B) duration less than 1 minute; C) stereotyped phenomenology in a particular patient; D) response to a treatment with carbamazepine/oxcarbazepine; and F) not better accounted for by another diagnosis. Probable VP is defined as follows: A) at least five attacks of spinning or non-spinning vertigo; B) duration less than 5 minutes; C) spontaneous occurrence or provoked by certain head-movements; D) stereotyped phenomenology in a particular patient; E) not better accounted for by another diagnosis. Ephaptic discharges in the proximal part of the 8th cranial nerve, which is covered by oligodendrocytes, are the assumed mechanism. Important differential diagnoses are Menière's disease, vestibular migraine, benign paroxysmal positional vertigo, epileptic vestibular aura, paroxysmal brainstem attacks (in multiple sclerosis or after brainstem stroke), superior canal dehiscence syndrome, perilymph fistula, transient ischemic attacks and panic attacks. Current areas of uncertainty in the diagnosis of VP are: a) MRI findings of vascular compression which are not diagnostic of the disease or predictive for the affected side because they are also observed in about 30% of healthy asymptomatic subjects; and b) response to treatment with carbamazepine/oxcarbazepine supports the diagnosis but there are so far no randomized controlled trials for treatment of VP. [ABSTRACT FROM AUTHOR]

Purpose: To delineate the association between otolithic dysfunction and orthostatic hypotension (OH). Methods: We retrospectively reviewed the medical records of 382 patients who presented with orthostatic dizziness at a tertiary dizziness center between July 2017 and December 2021. Patients were included for analyses when they had completed ocular (oVEMP) and/or cervical vestibular-evoked myogenic potentials (cVEMP), and head-up tilt table test with a Finometer (n = 155). We compared the results between the patients with OH (n = 38) and those with NOI (normal head-up tilt table test despite orthostatic intolerance, n = 117). Results: Thirty-eight patients with OH were further categorized as either classic (n = 30), delayed (n = 7), or initial (n = 1) types. Multivariable logistic regression showed that OH was associated with high baseline systolic BP (p = 0.046), presence of heart failure (p = 0.016), and unilateral oVEMP abnormalities (p = 0.016). n1 latency of oVEMP were negatively correlated with the maximal changes of systolic blood pressure (BP) in 15 s (Δ SBP15s, p = 0.013), 3 min (Δ SBP3min, p = 0.005) and 10 min (Δ SBP10min, p = 0.002). In contrast, the n1-p1 amplitude was positively correlated with Δ SBP15s (p = 0.029). Meanwhile, p13 latency of cVEMP was negatively correlated with Δ SBP10min (p = 0.018). Conclusions: Our study provides evidence of utricular dysfunction related to OH. [ABSTRACT FROM AUTHOR]

Introduction: The primary aim was to develop convolutional neural network (CNN)‐based artificial intelligence (AI) models for pneumothorax classification and segmentation for automated chest X‐ray (CXR) triaging. A secondary aim was to perform interpretability analysis on the best‐performing candidate model to determine whether the model's predictions were susceptible to bias or confounding. Method: A CANDID‐PTX dataset, that included 19,237 anonymized and manually labelled CXRs, was used for training and testing candidate models for pneumothorax classification and segmentation. Evaluation metrics for classification performance included Area under the receiver operating characteristic curve (AUC‐ROC), sensitivity and specificity, whilst segmentation performance was measured using mean Dice and true‐positive (TP)‐Dice coefficients. Interpretability analysis was performed using Grad‐CAM heatmaps. Finally, the best‐performing model was implemented for a triage simulation. Results: The best‐performing model demonstrated a sensitivity of 0.93, specificity of 0.95 and AUC‐ROC of 0.94 in identifying the presence of pneumothorax. A TP‐Dice coefficient of 0.69 is given for segmentation performance. In triage simulation, mean reporting delay for pneumothorax‐containing CXRs is reduced from 9.8 ± 2 days to 1.0 ± 0.5 days (P‐value < 0.001 at 5% significance level), with sensitivity 0.95 and specificity of 0.95 given for the classification performance. Finally, interpretability analysis demonstrated models employed logic understandable to radiologists, with negligible bias or confounding in predictions. Conclusion: AI models can automate pneumothorax detection with clinically acceptable accuracy, and potentially reduce reporting delays for urgent findings when implemented as triaging tools. [ABSTRACT FROM AUTHOR]

Background and Purpose: Trochlear palsy is the most common cause of vertical diplopia. The etiologies of trochlear palsy have shown a large discrepancy among studies. This study aimed to establish the clinical features and underlying etiologies of isolated trochlear palsy by recruiting the patients from all departments in a referral‐based university hospital. Methods: We reviewed the medical records of 1258 patients who had a confirmed diagnosis of isolated trochlear palsy at all departments of Seoul National University Bundang Hospital, Seongnam, South Korea, from 2003 to 2020. We also compared the proportion of etiologies with that of the patients pooled from previous studies. Results: The most common etiology was congenital (n = 330, 32.4%), followed by idiopathic (n = 256, 25.1%), microvascular (n = 212, 20.8%), and traumatic (n = 145, 14.2%). These four etiologies explained 92.5% of isolated trochlear palsy. Patients were mostly managed by ophthalmologists (n = 841, 82.5%), followed by neurologists (n = 380, 37.3%), emergency physicians (n = 197, 19.3%), neurosurgeons (n = 75, 7.4%), and others (n = 18, 1.8%). The etiologic distribution of isolated trochlear palsy in the current study did not differ from that of 2664 patients pooled from the previous studies. Conclusions: The proportion of etiologies of isolated trochlear palsy differs according to the age ranges of the patients and specialties involved in the management. The etiologic distribution of isolated trochlear palsy in the current study was comparable to the pooled result of previous reports. [ABSTRACT FROM AUTHOR]

Objective: To evaluate how often the positive sign of HINTS (Head-Impulse, Gaze Evoked Nystagmus, Test of Skew) appears in patients with acute peripheral vestibular lesion, HINTS findings were quantitatively measured and analyzed in patients with peripheral vestibulopathy accompanying spontaneous nystagmus.Methods: HINTS was evaluated in 14 vertigo patients with spontaneous nystagmus. Horizontal vestibulo-ocular reflex (VOR) gain was measured using the video head impulse test (vHIT). To evaluate gaze-evoked nystagmus (GEN), slow-phase velocities at different points of lateral gaze were measured and plotted, then the slope and its inverse value, the neural integrator time constant, were calculated. Skew deviation was tested using anaglyph filters to simulate the alternate cover test, and the degree and latency of vertical eyeball deviation were measured. The ABCD2 score was calculated to evaluate the risk of stroke.Results: Among 13 patients of peripheral vestibulopathy, 7 showed positive signs in HINTS (normal vHIT: 5, direction-changing GEN: 0, skew deviation: 3). One patient with a cerebellopontine angle tumor presented with both a peripheral and central pattern and showed positive HINTS findings (presence of direction-changing GEN). The mean VOR gain of patients with abnormal vHIT was 0.58±0.29 and 1.10±0.11 in the affected and contralateral side, respectively, while those in patients with normal vHIT were 1.04±0.21 and 1.13±0.12, respectively. The neural integrator time constant calculated from the mean slope of horizontal slow-phase velocity according to horizontal eye position was 42.9 s. The mean vertical eyeball deviation of patients with positive skew was 2.14±1.18° while uncovering the eye on the affected side, and -1.97±1.59° while uncovering the eye on the unaffected side. The median ABCD2 score of 14 patients was 2 (range, 1-3).Conclusions: HINTS findings were objectively measured in vertigo patients with spontaneous nystagmus. Although positive findings of HINTS have been recognized as a central sign, 54% (7/13) of cases with peripheral vestibulopathy showed positive HINTS signs. HINTS results should be interpreted carefully considering that a substantial proportion of peripheral vestibulopathy shows a positive HINTS sign. [ABSTRACT FROM AUTHOR]

These saccades were associated with alternating horizontal saccades, thus giving rise to a "saw-tooth" appearance, especially during downward saccades. According to a conductance-based model simulation, premature and poorly synchronized discharges from the degenerated IBNs cause breaks in the saccade trajectory and maladaptive superior colliculus activity, resulting in aberrant saccades that alter the intended trajectory of the ongoing saccades [[4]]. His fragmented vertical saccades were associated with alternating horizontal saccades, giving rise to a "saw-tooth" appearance, especially during downward saccades. The hypometric (stair-case pattern) vertical saccades were associated with alternating horizontal saccades, thus giving rise to a "saw-tooth" appearance, especially during downward saccades (Fig. [Extracted from the article]

Background: Fisher syndrome (FS) is characterized by a triad of ophthalmoplegia, ataxia, and areflexia. The lesion sites responsible for ataxia and ophthalmoplegia in FS require further exploration. The aim of this study was to determine involvement of the central nervous system in FS using 18F-fluorodeoxyglucose positron emission tomography (PET). Methods: Cerebral glucose metabolism of 10 patients with FS was compared with that of 60 age- and gendermatched normal controls using PET. For individual analyses, 15 age- and gender-matched controls were selected from the control group. Patients also underwent MRI of the brain and measurement of serum anti-GQ1b antibody. Results: Group analyses revealed increased metabolism in the cerebellar vermis and hemispheres, pontine tegmentum, midbrain tectum, left thalamus and right inferior frontal cortex (P<0.001, uncorrected). In contrast, the visual association cortices (Brodmann areas 18 and 19) showed decreased metabolism bilaterally. Individual analyses disclosed hypermetabolism in the cerebellar vermis or hemispheres (n=7), inferior frontal cortex (n=5) and brainstem (n=4, P<0.005, uncorrected). We also found a negative correlation between the cerebellar hypermetabolism and the interval from symptom onset to PET (r =-0.745, P=.0013). The hypermetabolism was normalized on follow-up PET with an improvement of the ophthalmoplegia and ataxia in one patient. Conclusions: These findings indicate an involvement of the central nervous system in FS, and the hypermetabolism in the cerebellum and brainstem suggests an antibody-associated acute inflammatory process as a mechanism of this autoimmune disorder. [ABSTRACT FROM AUTHOR]

Background and Objectives: Vestibular syncope is a condition in which vertigo‐induced hemodynamic changes cause syncope. This study investigated the clinical and laboratory findings of vestibular syncope and tried to refine our knowledge of the mechanism underlying this newly recognized entity. Methods: This study retrospectively analyzed 53 patients (33 women, median age = 63 years [interquartile range = 54–71 years]) with vestibular syncope from January 2017 to December 2021. To explain the mechanism of vestibular syncope, we incorporated a velocity‐storage model into the dual reflex pathways comprising the vestibulo‐sympathetic reflex and baroreflex and predicted the cardiovascular responses. Results: Twenty (37.7%) patients had multiple episodes of vestibular syncope, and seven (13.2%) had potentially life‐threatening injuries. Meniere's disease (20.8%) and benign paroxysmal positional vertigo (9.4%) were the most common underlying vestibular disorders. Abnormal vestibular function tests included impaired cervical vestibular‐evoked myogenic potentials (57.5%) and positive head impulse tests (31.0%). Orthostatic hypotension was found in 19.5% of patients. Dyslipidemia (30.2%) and hypertension (28.3%) were common medical comorbidities. The dual reflex pathways incorporating the function of the velocity‐storage circuit in the brainstem and cerebellum suggest that vestibular syncope is a neurally mediated reflex syncope associated with a sudden hemodynamic change during vertigo. This change can be arterial hypertension triggered by a false downward inertial cue, as suggested previously, or hypotension driven by a false upward inertial cue. Conclusions: Vestibular syncope is associated with various vestibular disorders and requires careful evaluation and intervention to prevent recurrent falls and significant injuries. [ABSTRACT FROM AUTHOR]

These corrective saccades were only noticeable during the bedside HITs and had been interpreted as back-up saccades. Herein, we describe overt back-up saccades during HITs due to hypermetric covert saccades in a patient with an acute circumscribed lesion involving the cerebellum, which were misinterpreted as reversed corrective saccades due to the hyperactive VOR during bedside examination. When these corrective saccades are hypermetric due to cerebellar dysfunction, the eyes would overshoot the target with corrective saccades in the opposite direction. (MP4 15487 KB) Graph: Supplementary file3 Video-head impulse tests show hypermetric covert corrective (red arrowhead) and overt back-up saccades (red arrow) during stimulation of the left horizontal semicircular canal and covert corrective saccades (blue arrowhead) during stimulation of the right horizontal canal. [Extracted from the article]

In central as well as peripheral vestibular lesions, right-beating horizontal nystagmus is almost always associated with clockwise (top poles of the eyes beating to the right ear) torsional nystagmus when observed and vice versa (concordant nystagmus). This study aimed to determine the etiologies and mechanisms of horizontal and torsional nystagmus beating in the opposite directions (discordant nystagmus). We reviewed the medical records of 16 consecutive patients with discordant horizontal–torsional nystagmus who had been evaluated at the dizziness clinics of Seoul National University Bundang Hospital (n = 11, from March 2003 to March 2021) and Korea University Medical Center (n = 5, from March 2019 to March 2021). The underlying etiologies included inferior vestibular neuritis (n = 7), Meniere's disease (n = 4), internuclear ophthalmoplegia (n = 3), medullary hemorrhage (n = 1), and normal pressure hydrocephalus (n = 1). The torsional nystagmus decreased during the gaze in the same direction (for instance, during rightward gaze in clockwise nystagmus) and increased during the gaze in the opposite direction. Head-impulse tests (HITs) were positive for the ipsilesional posterior canal (PC) in all 11 patients with unilateral peripheral vestibulopathy and two of the three patients with unilateral central vestibulopathy. Discordant horizontal–torsional nystagmus may be observed in peripheral as well as central lesions. Given the findings of HITs and modulation of spontaneous nystagmus during lateral gazes, discordant horizontal–torsional nystagmus may be ascribed to selective damage of the excitatory or inhibitory pathway from the PC that innervates the ipsilateral superior oblique and contralateral inferior rectus muscles. [ABSTRACT FROM AUTHOR]

The article discusses a case study of a 57-year-old man with multiple system atrophy (MSA) presenting with ocular flutter triggered specifically by vestibular stimulation, alongside various neurological symptoms including gait difficulty, oscillopsia, and dysarthria. It highlights the diagnostic challenges and neurological manifestations associated with MSA, emphasizing the role of vestibular and ocular motor deficits in differentiating this condition from other neurodegenerative disorders.