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Purpose of Review: The diagnosis of Meniere disease (MD) has based on characteristics of vertigo and findings of audiologic evaluation. This review focuses on the recent findings of the evolution of vestibular function and their underlying physiology during and between the attacks of MD and thus aims to help identify this common disorder with many faces according to the phase., Recent Findings: During the attacks, the direction of spontaneous nystagmus changes over time, beating initially toward the affected ear (irritative nystagmus), then toward the healthy ear (paretic nystagmus), and finally back toward the affected ear again (recovery nystagmus). Apart from these direction changes, atypical forms of spontaneous nystagmus, such as downbeat, discordant horizontal-torsional, and aperiodic alternating nystagmus, can be observed. Head impulse tests (HITs) are mostly normal during the irritative/recovery phases, but positive in more than half of patients during the paretic phase. By contrast, caloric tests are usually abnormal irrespective of the phases, although paradoxical caloric hyper-responsiveness can be observed in 18% of patients during the irritative/recovery phases. Thus, dissociation in the findings of caloric tests-HITs can be observed during and between the attacks. Horizontal head shaking tends to augment spontaneous nystagmus during each phase, while skull vibration mostly induces nystagmus beating toward the healthy ear irrespective of the phases. During the attacks, ocular vestibular-evoked myogenic potentials (VEMPs) may be enhanced, whereas cervical VEMPs are usually decreased during stimulation of the involved ear., Summary: Recognizing these evolutions of vestibular findings during and between the attacks of MD would provide insights into its pathophysiology and aid in treatments and diagnosis., Competing Interests: Drs. S.U. Lee, E. Park, H.J. Kim, and J.-Y. Choi report no disclosures. J.S. Kim serves as an Associate Editor of Frontiers in Neuro-otology and on the editorial boards of Frontiers in Neuro-ophthalmology, Journal of Neuro-ophthalmology, Journal of Vestibular Research, and Clinical and Translational Neuroscience. Full disclosure form information provided by the authors is available with the full text of this article at Neurology.org/cp. TAKE-HOME POINTS → The vestibular findings may fluctuate during the Meniere attacks, and those should be interpreted in consideration of the phases.→ The direction of spontaneous nystagmus changes over time, beating ipsilesionally (irritative/recovery phases) or contralesionally (paretic phase).→ Atypical spontaneous nystagmus, such as downbeat, discordant horizontal-torsional, or aperiodic alternating nystagmus, can be observed during the Meniere attacks to masquerade a central vestibulopathy.→ The results of caloric tests and head impulse tests (HITs) can be dissociated to show caloric canal paresis in the presence of normal HITs.→ Dynamic changes in these vestibular findings reflect the characteristic ictal vestibular physiology during the Meniere attacks., (© 2024 American Academy of Neurology.)

Objective: To determine the mechanism of ictal downbeat nystagmus in Ménière disease (MD), we compared the head impulse gain of the vestibulo-ocular reflex (VOR) for each semicircular canal between patients with (n = 7) and without (n = 70) downbeat nystagmus during attacks of MD., Methods: We retrospectively analyzed the results of video-oculography, video head-impulse tests, and cervical vestibular-evoked myogenic potentials (VEMPs) in 77 patients with definite MD who were evaluated during an attack., Results: Pure or predominant downbeat nystagmus was observed in 7 patients (9%) with unilateral MD during the attacks. All 7 patients showed spontaneous downbeat nystagmus without visual fixation with a slow phase velocity ranging from 1.5 to 11.2°/s (median 5.4, interquartile range 3.7-8.5). All showed a transient decrease of the head impulse VOR gains for the posterior canals (PCs) in both ears (n = 4) or in the affected ear (n = 3). Cervical VEMPs were decreased in the affected (n = 2) or both ears (n = 2) when evaluated during the attacks. Downbeat nystagmus disappeared along with normalization of the VOR gains for PCs after the attacks in all patients. During the attacks, the head impulse VOR gains for the PC on the affected side were lower in the patients with ictal downbeat nystagmus than in those without (Mann-Whitney U test, p < 0.001), while the gains for other semicircular canals did not differ between the groups., Conclusion: Downbeat nystagmus may be observed during attacks of MD due to an asymmetry in the vertical VOR or saccular dysfunction. MD should be considered in recurrent audiovestibulopathy and ictal downbeat nystagmus., (© 2020 American Academy of Neurology.)

Objective: To assess the effect of vitamin D and calcium supplementation in preventing recurrences of benign paroxysmal positional vertigo (BPPV)., Methods: We performed an investigator-initiated, blinded-outcome assessor, parallel, multicenter, randomized controlled trial in 8 hospitals between December 2013 and May 2017. Patients with confirmed BPPV were randomly assigned to the intervention (n = 518) or the observation (n = 532) group after successful treatment with canalith repositioning maneuvers. The primary outcome was the annual recurrence rate (ARR). Patients in the intervention group had taken vitamin D 400 IU and 500 mg of calcium carbonate twice a day for 1 year when serum vitamin D level was lower than 20 ng/mL. Patients in the observation group were assigned to follow-ups without further vitamin D evaluation or supplementation., Results: The intervention group showed a reduction in the ARR (0.83 [95% confidence interval (CI), 0.74-0.92] vs 1.10 [95% CI, 1.00-1.19] recurrences per 1 person-year) with an incidence rate ratio of 0.76 (95% CI, 0.66-0.87, p < 0.001) and an absolute rate ratio of -0.27 (-0.40 to -0.14) from intention-to-treat analysis. The number needed to treat was 3.70 (95% CI, 2.50-7.14). The proportion of patients with recurrence was also lower in the intervention than in the observation group (37.8 vs 46.7%, p = 0.005)., Conclusions: Supplementation of vitamin D and calcium may be considered in patients with frequent attacks of BPPV, especially when serum vitamin D is subnormal., Classification of Evidence: This study provides Class III evidence that for patients with BPPV, vitamin D and calcium supplementation reduces recurrences of BPPV., (© 2020 American Academy of Neurology.)

Objective: To determine the vestibulo-ocular reflex (VOR) performance during the attacks of Menière's disease (MD) using video head-impulse tests (video-HITs) according to each ictal phase., Study Design: Retrospective case series review., Methods: We analyzed the results of video-HITs in 24 patients with unilateral definite MD during and between the attacks., Results: The head impulse gain of the VOR was usually normal (81%, 39 of the 48 semicircular canals [SCCs] in 16 patients) in the affected ear during the irritative or recovery phase, and did not differ from that for each SCC between the attacks (horizontal [HCs], p = 0.412; anterior [ACs], p = 0.920; posterior canals [PCs], p = 0.477). During the paretic phase, however, the head impulse gains of the VOR were equally normal (22/42, 52%) or decreased (20/42, 48%) for the affected ear (42 SCCs in 14 patients). The gains for the HCs were lower during the paretic phase than those between the attacks in the affected ear, while those for the ACs and PCs did not differ (HCs, p = 0.001; ACs, p = 0.158, PCs, p = 0.401). Covert saccades were more frequently observed even in the presence of normal VOR gains during the paretic phase as well., Conclusion: During the attacks of MD, HITs are usually normal during the irritative/recovery phases, but become positive in more than a half of the patients during the paretic phase. This evolution in the ictal findings of HITs may reflect characteristic ictal vestibular discharges in MD and should be considered in evaluating patients with MD according to each ictal phase during the attacks.

Objectives: To develop a simple questionnaire for self-diagnosis of benign paroxysmal positional vertigo (BPPV)., Methods: We developed a questionnaire that consisted of 6 questions, the first 3 to diagnose BPPV and the next 3 to determine the involved canal and type of BPPV. From 2016 to 2017, 578 patients with dizziness completed the questionnaire before the positional tests, a gold standard for diagnosis of BPPV, at the Dizziness Clinic of Seoul National University Bundang Hospital., Results: Of the 578 patients, 200 were screened to have BPPV and 378 were screened to have dizziness/vertigo due to disorders other than BPPV. Of the 200 patients with a questionnaire-based diagnosis of BPPV, 160 (80%) were confirmed to have BPPV with positional tests. Of the 378 patients with a questionnaire-based diagnosis of non-BPPV, 24 (6.3%) were found to have BPPV with positional tests. Thus, the sensitivity, specificity, and precision of the questionnaires for the diagnosis of BPPV were 87.0%, 89.8%, and 80.0% (121 of 161, 95% confidence interval 74.5%-85.5%). Of the 200 patients with a questionnaire-based diagnosis of BPPV, 30 failed to respond to the questions 4 through 6 to determine the involved canal and type of BPPV. The questionnaire and positional tests showed the same results for the subtype and affected side of BPPV in 121 patients (121 of 170, 71.2%)., Conclusion: The accuracy of questionnaire-based diagnosis of BPPV is acceptable., Classification of Evidence: This study provides Class III evidence that, in patients with dizziness, a questionnaire can diagnose BPPV with a sensitivity of 87.0% and a specificity of 89.8%., (© 2019 American Academy of Neurology.)

Background: The mechanisms of pendular seesaw nystagmus (SSN) remain unknown., Methods: We evaluated modulation of pendular SSN by removal of visual fixation, convergence, and positional changes in 2 patients, one with bitemporal hemianopia due to a traumatic damage of the optic chiasm and the other with platybasia compressing the medulla and lower cerebellum., Results: In both patients, the pendular SSN markedly decreased or disappeared with convergence, without visual fixation in darkness, during static head tilt toward each shoulder while sitting and while supine., Conclusions: The similar patterns of nystagmus modulation observed in our patients with a different etiology indicate a common role of both visual and otolithic inputs in generating pendular SSN.

Background: The brainstem contains numerous structures including afferent and efferent fibers that are involved in generation and control of eye movements., Evidence Acquisition: These structures give rise to distinct patterns of abnormal eye movements when damaged. Defining these ocular motor abnormalities allows a topographic diagnosis of a lesion within the brainstem., Results: Although diverse patterns of impaired eye movements may be observed in lesions of the brainstem, medullary lesions primarily cause various patterns of nystagmus and impaired vestibular eye movements without obvious ophthalmoplegia. By contrast, pontine ophthalmoplegia is characterized by abnormal eye movements in the horizontal plane, while midbrain lesions typically show vertical ophthalmoplegia in addition to pupillary and eyelid abnormalities., Conclusions: Recognition of the patterns and characteristics of abnormal eye movements observed in brainstem lesions is important in understanding the roles of each neural structure and circuit in ocular motor control as well as in localizing the offending lesion.

Objective: To define a disorder characterized by recurrent spontaneous vertigo (RSV) of unknown etiology and interictal headshaking nystagmus (HSN)., Methods: We characterized HSN in 35 patients with RSV-HSN compared to that recorded in randomly selected patients with compensated vestibular neuritis (VN), vestibular migraine (VM), and Ménière disease (MD)., Results: The estimated time constant (TC) of the primary phase of HSN was 12 seconds (95% confidence interval [CI] 12-13) in patients with RSV-HSN, which was larger than those in patients with VN (5 seconds, 95% CI 4-5), VM (5 seconds, 95% CI 5-6), or MD (6 seconds, 95% CI 5-6). TCs of the horizontal vestibulo-ocular reflex were also larger during the rotatory chair test in patients with RSV-HSN. Among the 35 patients with RSV-HSN, 7 showed vigorous long-lasting HSN with a peak slow-phase velocity >50.0°/s. In 5 patients (5 of 7, 71%) with vigorous HSN, HSN could have been induced even with headshaking for only 2 to 5 seconds. Long-term prognosis was favorable, with a resolution or improvement of the symptoms in more than half of the patients during the median follow-up of 12 (range 2-58) years from symptom onset. None developed VM, MD, or cerebellar dysfunction during the follow-up., Conclusion: The clinical features and characteristics of HSN in our patients indicate a hyperactive and asymmetric velocity-storage mechanism that gives rise to intermittent attacks of spontaneous vertigo probably when marginal compensation of underlying pathology is disrupted by endogenous or exogenous factors., (© 2018 American Academy of Neurology.)

The head impulse test (HIT) is used to evaluate the vestibulo-ocular reflex (VOR) during a high-velocity head rotation. Corrective catch-up saccades that occur during or after the HITs usually indicate peripheral vestibular hypofunction, whereas in acute vestibular syndrome, normal clinical (bedside) HITs should prompt a search for a central lesion. However, recent quantitative studies that evaluated HITs using magnetic search coils or video-based techniques have demonstrated that specific patterns of HIT abnormalities are associated with central vestibular disorders. While normal clinical HITs are typical of central lesions, discrepancies have been observed between clinical and quantitative HITs. The horizontal head impulse VOR gains can be significantly reduced unilaterally or bilaterally (positive HITs) in lesions involving the vestibular nucleus, nucleus prepositus hypoglossi, or flocculus. In diffuse cerebellar lesions, the VOR gain during horizontal head impulses may increase (hyperactive) with corrective saccades directed the opposite way. The presence of cross-coupled vertical corrective saccades during horizontal HITs is also suggestive of diffuse cerebellar lesions. Lesions involving the vestibular nucleus, medial longitudinal fasciculus, and cerebellum may show decreased or increased gains of the VOR during vertical HITs. Defining the differences in patterns observed during abnormal HITs may help practitioners localize the responsible lesions in both central and peripheral vestibulopathy., (© 2018 American Academy of Neurology.)

Objective: To determine the efficacy of prophylactic medications for migraine in reducing associated dizziness and motion sickness., Study Design: Multicenter prospective observational study., Setting: Nationwide 9 Dizziness Clinics in South Korea., Patients: One hundred thirty-eight patients who required a preventive medication for migraine accompanied by dizziness and motion sickness., Intervention: At least one of the prophylactic medications was prescribed among the beta-blockers, calcium channel blockers, tricyclic antidepressants, and antiepileptic drugs., Main Outcome Measure: For 3 months from the index visit, the patients had monthly assessments of the headache (frequency and duration), dizziness handicap inventory, University of California Los Angeles dizziness questionnaire, vertigo symptom scale, and motion sickness score., Results: The prophylactic medications significantly improved the headache profiles, all three parameters of dizziness (dizziness handicap inventory, University of California Los Angeles dizziness questionnaire, and vertigo symptom scale), and severity of motion sickness (p < 0.001)., Conclusion: The prophylactic medication for migraine also improves associated dizziness and motion sickness as well as the headaches.

Patients with congenital ocular motor apraxia (OMA) typically show head thrusts while attempting to shift gaze. In congenital OMA, this compensatory head motion mostly occurs in the horizontal plane. Two patients with acquired palsy of voluntary vertical gaze and continuous upward gaze deviation, one from aortic surgery and the other from multiple infarctions involving the mesodiencephalic junction, showed intermittent downward head thrusting to redirect the eyes straight ahead or downward. The head thrusting behavior improved markedly after surgical correction of the upward gaze deviation in one patient. Vertical head thrusting may be a characteristic sign of acquired vertical gaze palsy when combined with vertical gaze deviation.

Background: This phase III trial compared the efficacy and safety of gemcitabine plus capecitabine (GemCap) versus single-agent gemcitabine (Gem) in advanced pancreatic cancer as first-line chemotherapy., Methods: A total of 214 advanced pancreatic cancer patients were enrolled from 16 hospitals in South Korea between 2007 and 2011. Patients were randomly assigned to receive GemCap (oral capecitabine 1660 mg/m plus Gem 1000 mg/m by 30-minute intravenous infusion weekly for 3 weeks followed by a 1-week break every 4 weeks) or Gem (by 30-minute intravenous infusion weekly for 3 weeks every 4 weeks)., Results: Median overall survival (OS) time, the primary end point, was 10.3 and 7.5 months in the GemCap and Gem arms, respectively (P = 0.06). Progression-free survival was 6.2 and 5.3 months in the GemCap and Gem arms, respectively (P = 0.08). GemCap significantly improved overall response rate compared with Gem alone (43.7% vs 17.6%; P = 0.001). Overall frequency of grade 3 or 4 toxicities was similar in each group. Neutropenia was the most frequent grade 3 or 4 toxicity in both groups., Conclusion: GemCap failed to improve OS at a statistically significant level compared to Gem treatment. This study showed a trend toward improved OS compared to Gem alone. GemCap and Gem both exhibited similar safety profiles., Competing Interests: The authors have no conflicts of interest to disclose.

Background: The trochlear (fourth) nerve is the only cranial nerve that decussates before emerging from the posterior aspect of the brainstem. Lesions involving the trochlear nucleus or fascicles mostly give rise to contralesional superior oblique palsy (SOP)., Methods: We report 2 patients with SOP on the side of intraaxial lesions with a literature review on central trochlear palsy., Results: The lesions are more commonly located posterior to the cerebral aqueduct in patients with ipsilesional SOP than in those with contralesional SOP., Conclusions: Intraaxial lesions may cause ipsilesional or contralesional SOP depending on the lesion location along the course of trochlear fascicle in the brainstem.

Objectives: We evaluated the value of carbohydrate antigen 19-9 (CA 19-9) as a pancreatic cancer (PC) screening tool in an asymptomatic new-onset diabetic patients., Methods: Medical records of asymptomatic patients newly diagnosed with diabetes mellitus (DM) were reviewed retrospectively at our hospital from January 2004 to January 2013., Results: In total, 2363 asymptomatic diabetic patients with CA 19-9 measurements were enrolled. Of them, 68 (2.9%) were diagnosed with PC. In the 1719 patients who had CA 19-9 measured within 1 year after the DM diagnosis, a total of 51 (3.0 %) patients developed PC and the odds ratio (OR) of PC according to higher CA 19-9 than normal upper limit, 37 IU/mL was 5.57 (P < 0.001). In 248 patients checked CA 19-9 between 1 and 2 years after DM diagnosis, PC was detected in 9 (3.6%) cases and OR of high CA 19-9 was 4.51 (P = 0.019). However, beyond 2 years, the OR for PC showed no statistical significance. The patients with high CA 19-9 levels tended to have more advanced-stage disease., Conclusions: Early check-up of CA 19-9 could be a useful marker for screening for PC in asymptomatic patients with new-onset DM in the first 2 years.

Background and Purpose: The characteristics of infarctions restricted to the dorsal medulla have received little attention. This study aimed to define the distinct clinical features of dorsal medullary infarction., Methods: Of the 172 patients with a diagnosis of medullary infarction at Seoul National University Bundang Hospital from 2003 to 2014, 18 patients with isolated dorsal medullary infarction were subjected to analyses of clinical and laboratory findings., Results: All patients presented acute isolated vestibular syndrome with dizziness/vertigo and imbalance. Almost all patients (17/18, 94%) showed the signs from involvements of the vestibular nuclei, nucleus prepositus hypoglossi, or inferior cerebellar peduncle, which included direction-changing gaze-evoked nystagmus (n=12), negative head-impulse tests (n=8), skew deviation (n=7), central patterns of head-shaking nystagmus (n=6), and spontaneous nystagmus (n=2). Initial magnetic resonance imagings including diffusion-weighted images were negative in 7 patients (39%). Twelve patients (67%) showed a progression and developed additional neurological abnormalities, but the neurological outcomes were favorable., Conclusions: The presence of central vestibular signs allows bedside differentiation of isolated vestibular syndrome because of dorsal medullary infarction from acute peripheral vestibular disorders. Because initially false-negative magnetic resonance imagings and subsequent progression are frequent in dorsal medullary infarction, early recognition through scrutinized evaluation is important for proper managements., (© 2015 American Heart Association, Inc.)