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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 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.

Dr. Sharpe was a leading eye movement researcher who had also been the editor of this journal. We wish to mark the 10th anniversary of his death by providing a sense of what he had achieved through some examples of his research.

The velocity-storage circuit participates in the vestibulopostural reflex, but its role in the postural reflex requires further elucidation. The velocity-storage circuit differentiates gravitoinertial information into gravitational and inertial cues using rotational cues. This implies that a false rotational cue can cause an erroneous estimation of gravity and inertial cues. We hypothesized the velocity-storage circuit is a common gateway for all vestibular reflex pathways and tested that hypothesis by measuring the postural and perceptual responses from a false inertial cue estimated in the velocity-storage circuit. Twenty healthy human participants (40.5 ± 8.2 years old, 6 men) underwent two different sessions of earth-vertical axis rotations at 120°/s for 60 s. During each session, the participants were rotated clockwise and then counterclockwise with two different starting head positions (head-down and head-up). During the first (control) session, the participants kept a steady head position at the end of rotation. During the second (test) session, the participants changed their head position at the end of rotation, from head-down to head-up or vice versa. The head position and inertial motion perception at the end of rotation were aligned with the inertia direction anticipated by the velocity-storage model. The participants showed a significant correlation between postural and perceptual responses. The velocity-storage circuit appears to be a shared neural integrator for the vestibulopostural reflex and vestibular perception. Because the postural responses depended on the inertial direction, the postural instability in vestibular disorders may be the consequence of the vestibulopostural reflex responding to centrally estimated false vestibular cues.SIGNIFICANCE STATEMENTThe velocity-storage circuit appears to participate in the vestibulopostural reflex, which stabilizes the head and body position in space. However, it is still unclear whether the velocity-storage circuit for the postural reflex is in common with that involved in eye movement and perception. We evaluated the postural and perceptual responses to a false inertial cue estimated by the velocity-storage circuit. The postural and perceptual responses were consistent with the inertia direction predicted in the velocity-storage model and were correlated closely with each other. These results show that the velocity-storage circuit is a shared neural integrator for vestibular-driven responses and suggest that the vestibulopostural response to a false vestibular cue is the pathomechanism of postural instability clinically observed in vestibular disorders.

The impedance spectroscopy analysis is utilized to probe the modifications of charge carrier dynamics arising from interface mixing in a solution-processed organic light emitting diode.

Purpose: This study aimed to conduct a scoping review of studies on interventions for the prevention of safety accidents involving infants. Methods: The scoping review method by Arksey and O'Malley was used to conduct an overview based on information spanning a wide range of fields. Multiple electronic databases, PubMed, CINAHL, RISS, and KISS, were searched for articles written in English or Korean published from 2012 to the present on safety accident prevention interventions. A total of 2,137 papers were found, and 20 papers were ultimately analyzed. Results: Most studies were conducted in the United States (55.0%) and in the medical field (45.0%), and most were experimental studies (35.0%). The results were organized across five categories: 1) preventive precautions, 2) characteristics of children's developmental stages, 3) encouraging voluntary participation, 4) continuity of interventions, and 5) teaching methods. Conclusion: Safety accident prevention interventions should cover the establishment of a safe home environment, include voluntary participation, and provide routine follow-up interventions. Additionally, practical training and teaching methods that incorporate feedback rather than a lectureoriented approach should be adopted.

Vibratory stimulation of the sternocleidomastoid muscles or the skull may enhance vestibular asymmetry and evoke nystagmus. We report prominent downbeating vibration-induced nystagmus (VIN) in a patient with paraneoplastic cerebellar degeneration due to cervical cancer with positive serum anti-Ri antibody. A 47-year-old woman developed spontaneous upbeat nystagmus present with and without visual fixation. Nystagmus decreased during lateral and upward gaze. Downbeat nystagmus emerged during convergence and after horizontal head shaking for approximately 15 seconds and during vibratory stimulation of the mastoids and forehead. Additional findings included positional downbeat nystagmus, impaired smooth pursuit, hypermetric horizontal saccades, and truncal ataxia. During video-head impulse tests, the gains of the vestibulo-ocular reflex (VOR) were normal for both horizontal semicircular canals but increased for both anterior canals and decreased for both posterior canals. Horizontal head impulses produced cross-coupled downward corrective saccades. Given the asymmetric vertical VOR, downbeat VIN observed in our patient may be ascribed to enhanced upward bias of the VOR due to vestibulocerebellar dysfunction during the vibratory stimuli. Vibration-induced downbeat nystagmus should be added to the list of central vestibular signs and is likely due to cerebellar dysfunction.

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.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.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.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.

To delineate the association between otolithic dysfunction and orthostatic hypotension (OH).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).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 ([Formula: see text]SBPOur study provides evidence of utricular dysfunction related to OH.

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.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.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.Vestibular syncope is associated with various vestibular disorders and requires careful evaluation and intervention to prevent recurrent falls and significant injuries.

Purpose: This study aimed to examine the association of COVID-19 vaccine attitudes and cognitions of COVID-19-related stigma with vaccine hesitancy among college students.Methods: This cross-sectional study using a web-based survey was conducted with 242 college students in April 2021 before Korea’s national COVID-19 vaccination program had begun. Data were analyzed using multinominal logistic regression analyses.Results: Of the participants who were unsure of their intention to receive the COVID-19 vaccine, 66.0% had less experience with flu vaccinations and were 1.43 times more likely to report a mistrust of vaccine benefits (OR=1.43, CI=1.22, 1.68). Those with no intention of receiving the vaccine were 25.0% less likely to be aware of COVID-19 stigma (OR=0.75, CI=0.65, 0.86), 2.08 times more likely to mistrust vaccine benefits (OR=2.08, CI=1.62, 2.68), and 1.53 times more likely to worry about an unforeseen future negative side effects from vaccination (OR=1.53. CI=1.16, 2.00).Conclusion: Nurses could play an important role in educating college students about vaccination benefits, including reviewing vaccines’ side effects with evidence, to reduce vaccine hesitancy. College students who have less empathy for others regarding COVID-19 infection might have higher COVID-19 vaccine hesitancy. Accordingly, explaining to students the necessity of their vaccination in preventing transmission to the surrounding community and vulnerable populations is critical.

Leave passes provide authorized leave for hospitalized patients from a psychiatric inpatient unit. Although providing day passes was once a relatively common practice, there are relatively few data describing their safety and efficacy. This descriptive study examines the use of leave passes in an adult inpatient unit at a university hospital between 2017 and 2021, with attention to reasons for granting the day pass, duration, and outcome of the pass. During the study period, 10 patients with primary psychotic or mood disorders received 12 passes for housing coordination, COVID-19 vaccination, or major family events. There were no fatalities or abscondments. One patient experienced severe agitation and engaged in nonsuicidal self-injurious behavior. A second patient showed mild, redirectable psychomotor agitation upon return to the unit. The remaining 10 passes were uneventful. Our findings support the view that patients with diverse diagnoses can safely be provided leave from an inpatient setting with adequate planning and support, yielding a low incidence of adverse events.

This study investigated emergency nurses' attitudes and perceptions about personal protective equipment and their association with the willingness to care for COVID-19 patients.Emergency nurses are at increased risk for COVID-19 infection as frontline workers and must wear personal protective equipment while attending suspected and confirmed COVID-19 patients.In September 2021, 188 nurses in four emergency departments completed online questionnaires.Multivariable logistic regression demonstrated that as perceptions of COVID-19 infection risk increased by 1 point, 26% of nurses were willing to care of COVID-19 patients. The willingness to care for COVID-19 patients increased in their attitudes by 1.16 point and perceptions by 1.08 points about PPE.Perceptions of the risk of infection exposure and confidence in safety of personal protective equipment are associated with nurses' willingness to care for COVID-19 patients.Nurse managers need to assess nurses' needs for safety and provide a supportive climate to mitigate their concerns regarding infection risk and encourage nurses' willingness to care for patients. Nurse managers should provide precise guidelines on correct personal protective equipment use. Repetitive training on personal protective equipment should be provided to encourage nurses' adaptation to its use.

This paper presents diagnostic criteria for vascular vertigo and dizziness as formulated by the Committee for the Classification of Vestibular Disorders of the Bárány Society. The classification includes vertigo/dizziness due to stroke or transient ischemic attack as well as isolated labyrinthine infarction/hemorrhage, and vertebral artery compression syndrome. Vertigo and dizziness are among the most common symptoms of posterior circulation strokes. Vascular vertigo/dizziness may be acute and prolonged (≥24 hours) or transient (minutes to

Differentiation of spinocerebellar ataxia type 17 (SCA17) from Huntington's disease (HD) is often challenging since they share the clinical features of chorea, parkinsonism, and dystonia. The ocular motor findings remain to be elucidated in SCA17, and may help differentiating SCA17 from HD. We retrospectively compared the ocular motor findings of 11 patients with SCA17 with those of 10 patients with HD. In SCA17, abnormal ocular motor findings included impaired smooth pursuit (9/11, 82%), dysmetric saccades (9/11, 82%), central positional nystagmus (CPN, 7/11, 64%), abnormal head-impulse tests (4/11, 36%), and horizontal gaze-evoked nystagmus (GEN, 3/11, 27%). Among these, CPN was more frequently observed in SCA17 than in HD (7/11 (64%) vs. 0/10 (0%), p = 0.004) while saccadic slowing was more frequently observed in HD than in SCA17 (8/10 (80%) vs. 2/11 (18%), p = 0.009). Of six patients with follow-up evaluation, five later developed bilateral saccadic hypermetria (n = 4), GEN (n = 1), CPN (n = 1), bilaterally abnormal smooth pursuit (n = 1), and hyperactive head-impulse responses (n = 1) along with a clinical decline. Ocular motor abnormalities can be utilized as a diagnostic marker for differentiation of SCA17 from HD as well as a surrogate marker for clinical decline in SCA17.

Objectives Recent advancements in high-resolution imaging have improved the diagnostic assessment of magnetic resonance imaging (MRI) for intralabyrinthine schwannoma (ILS). This systematic review aimed to evaluate the diagnostic performance of MRI for patients with ILS. Methods Ovid-MEDLINE and EMBASE databases were searched for related studies on the diagnostic performance of MRI for patients with ILS published up to February 10, 2020. The primary endpoint was the diagnostic performance of MRI for ILS. The quality of the enrolled studies was assessed using tailored questionnaires and the Quality Assessment of Diagnostic Accuracy Studies-2 criteria. Results Overall, 6 retrospective studies that included 122 patients with ILS from a parent population of 364 were included. The sample size, parent population and its composition, reference standard, detailed parameters of MRI, and even the diagnostic methods varied between the studies. The studies had moderate quality. The sensitivity of combination of T2WI and CE-T1WI was over 90%. Relative sensitivity of T2WI comparative to CE-T1WI ranged from 62% to 100%, and the specificity were 100%. Conclusions MRI has acceptable diagnostic performance for ILS. There is a need for well-organized research to reduce the factors causing heterogeneity.

ObjectTo study multimodal neuroimaging study including resting state functional MRI (rs-fMRI), anatomical connectivity and brain morphology in patients with bilateral vestibulopathy (BVP) and relationship with clinical correlation.MethodsThirteen patients with BVP (7 women; mean age ± SD = 63.5 ± 14.7 years, 22–80 years) and eighteen age and gender-matched controls were compared rs-fMRI and anatomical MRI. Also, we analyzed the relationship between multimodal neuroimaging and Dizziness Handicap Inventory score (DHI), Vestibular Disorders Activities of Daily Living Scale (VDRL), Geriatric Depression Scale (GDS) and Hospital Anxiety and Depression Scale (HADS).ResultsCompared with controls, BVP patients showed decreased functional connectivity among the key nodes of the salience network, auditory (including vestibular) network, bilateral posterior parahippocampal gyri, bilateral paracingulate gyri, and right frontoparietal network, and the anatomical connectivity in the right cerebellum, corpus callosum tapetum, and left fornix. BVP patients showed decreased gray matter volume in the bilateral parahippocampal gyri, right precentral gyrus, anterior cingulate gyrus, and right middle temporal gyrus and increased gray matter volume in the right superior frontal gyrus compared with controls. Correlation analyses showed rs-fMRI and clinical variables showed no significant result. DHI correlated negatively with anatomical connectivity in the bilateral frontal parahippocampal cingulum, corpus callosum, right inferior fronto-occipital fasciculus, bilateral fornix, and gray matter volumes in the bilateral middle occipital gyri, right superior occipital gyrus, left angular gyrus, and right cuneus in BVP. VADL correlated negatively with Anatomical connectivity in the corpus callosum, bilateral fornix, bilateral cerebellum, bilateral superior and anterior thalamic radiation, right inferior fronto-occipital fasciculus, bilateral fronto-parietal cingulum, right dentatoruburothalamic tract and gray matter volumes in the right angular gyri, bilateral parahippocampal gyri, right middle temporal gyrus, right cuneus, bilateral inferior occipital gyri, left middle occipital gyrus, right superior frontal gyrus, left fusiform gyrus, bilateral caudate, left cerebellar crus, and bilateral calcarine gyri in BVP.ConclusionsThis study identified reductions in the volume of the hippocampus and alterations in functional and anatomical connectivity that concurs with previously established characteristics of BVP. The degree of disability can be inferred from the change in the connectivity and volume between vestibular cortical areas and their network.

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 2-fold 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.

Opsoclonus refers to saccadic oscillations without an intersaccadic interval occurring in multiple planes. Opsoclonus mostly indicates dysfunction of the brainstem or cerebellum. We report opsoclonus induced by horizontal head-shaking without other signs of brainstem or cerebellar dysfunction in two patients with vestibular migraine (VM). The development of opsoclonus after horizontal head-shaking indicate unstable or hyperactive neural circuits between the excitatory and inhibitory saccadic premotor burst neurons in these patients with VM.

Background Several studies suggest that antibiotic use may affect overall cancer incidence, but the association between antibiotics and prostate cancer is still unclear. Methods A population-based retrospective cohort study was conducted using the Korean National Health Insurance Service (NHIS) database. 1,032,397 individuals were followed up from January 1, 2007, to December 31, 2019. Multivariate Cox hazards regression was utilized to calculate adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for the risk of prostate cancer according to accumulative days of antibiotic use and the number of antibiotic classes used. Results Individuals who used antibiotics for 180 or more days had a higher risk of prostate cancer (aHR, 1.46; 95% CI, 1.11-1.91) than those who did not use antibiotics. Also, individuals who used four or more kinds of antibiotics had a higher risk of prostate cancer (aHR, 1.18; 95% CI, 1.07-1.30) than antibiotic non-users. A similar trend was observed among participants who underwent health examinations. Conclusion Our findings suggest that long-term use of antibiotics may affect prostate cancer incidence. Further studies are needed to improve understanding of the association between antibiotic use and prostate cancer incidence.

The current review covers recent advances in bilateral vestibulopathy (BVP) in terms of its etiology, diagnosis, and treatments.The etiology of BVP depends on its clinical course and associated findings, and genetic abnormalities are increasingly recognized in isolated as well as complicated form of BVP. Recent developments in evaluation of the vestibular function have greatly enhanced the detection of BVP, and introduction of the consensus diagnostic criteria by Barany Society has facilitated research on BVP. Vestibular prosthesis may improve vestibular function, posture, gait and quality of life in patients with BVP and would expand the therapeutic options for BVP in near future.Genetics is expanding its role in identifying the causes of BVP of hitherto unknown etiology. The detection and investigation of BVP have been greatly enhanced by introduction of consensus diagnostic criteria and recent developments in methodology evaluating the vestibular function. Vestibular prothesis appears promising in managing BVP.http://links.lww.com/CONR/A59.

A 66-year-old hypertensive and diabetic male presented with acute vestibular syndrome for three days. HINTS plus examination was performed. The horizontal head impulse test was positive on the left side. Video oculography showed centripetal nystagmus on gaze testing in the dark and test of skew was negative. There was no new hearing loss on the finger rub test. On neurological examination, he had severe postural instability and saccadic smooth pursuit. Radio-imaging studies were conducted to rule out the possibility of stroke. CT brain showed infarction in the territory of the medial branch of the right posterior inferior cerebellar artery. MRI brain confirmed the diagnosis. Thus, posterior circulation stroke can present with acute vestibular syndrome mimicking acute unilateral vestibulopathy. However, the presence of associated neurological symptoms like gait ataxia, centripetal nystagmus and vascular risk factors pointed towards a central cause. Clinical evaluation suggesting a peripheral lesion should never be taken in isolation and needs to be correlated with other associated signs. We describe centripetal nystagmus without fixation as a new oculomotor sign in acute vestibular syndrome.

The integrity of the vestibulo-ocular reflex (VOR) remains to be delineated in patients with parkinsonism. We aimed to define the findings of the VOR using head-impulse tests (HITs) and their differential diagnostic value in patients with Parkinson’s disease (PD) and multiple system atrophy (MSA). From December 2019 to January 2021, 30 patients with PD and 23 patients with MSA (17 with cerebellar-type MSA and 6 with parkinsonian-type MSA) had a video-oculographic recording of HITs at two university hospitals in South Korea. Reversed (p = 0.034) and perverted (p = 0.015) catch-up saccades were more frequently observed in MSA than in PD during HITs. The gain difference between the ACs and the PCs were larger in MSA than in PD (p = 0.031), and positively correlated with the disease duration in patients with MSA (Spearman’s coefficient = 0.512, p = 0.012). Multivariate logistic regression analysis showed that reversed (p = 0.044) and perverted (p = 0.039) catch-up saccades were more frequently associated with MSA than with PD during HITs. In conclusion, HITs aid in differentiation of MSA from PD, and may serve as a surrogate marker for the clinical decline.

Displays in electronic devices visualize digital information, which is essential for humans to ultimately understand and use the Internet of Things (IoT) technology. Along with the evolution of several electrical components for flexible displays, developing flexible pressure-sensitive adhesives (PSA) is also important. In this study, a pattern of crosslinking density was applied to a PSA during the ultraviolet (UV) curing process to secure adhesion, transparency, stress relaxation, and supplement the strain recovery performance. We measured the modulus of each pattern region by atomic force microscopy (AFM) and confirmed whether the UV pattern PSA was prepared through the implementation of differential crosslinking density. Additionally, we measured dynamic mechanical analysis (DMA) strain recovery test, rheometer, peel strength, probe tack, and transmittance to confirm the effect of the given crosslinking density pattern on the overall physical properties of PSA.

Episodic ataxia type 2 (EA2) can present diverse ocular motor abnormalities, but few studies have systematically evaluated vestibular function during the interictal periods. This study aimed to determine vestibular impairments in patients with EA2 during the interictal periods. We recruited 17 patients with genetically confirmed EA2 (10 men, age range = 16–85 years, median = 32 years). We systematically evaluated the vestibular function by measuring the semicircular canals (SCCs) function with bithermal caloric tests, rotatory chair test, and video head impulse test (vHIT), and the otolith function with subjective visual vertical (SVV) tilt and variability, and cervical and ocular vestibular-evoked myogenic potentials (VEMPs). Patients with EA2 commonly showed abnormal VOR responses at least for one SCC with high-acceleration, high-frequency head impulses (14/16, 88%), and impaired visual-vestibular interaction (7/12, 58%). In response to low acceleration and frequency stimuli, the VOR gains were generally normal. The majority of EA2 patients had impairments in at least one of the otolith function tests (13/16, 81%): SVV tilt or variability (7/14, 50%), oVEMP (8/15, 53%), and cVEMP (4/16, 25%). Vestibular impairments are common in EA2 even during the interictal periods. Selective decrease in the VOR responses during higher acceleration stimuli along with impaired visual-vestibular interaction and otolith function suggests degeneration of the vestibulocerebellum or vestibular nuclei.