Positional Nystagmus Research Articles

Nystagmus in adult patients with acute otitis media or otitis media with effusion without dizziness.

The present study aimed to investigate the incidence and patterns of nystagmus in adult patients with acute otitis media (AOM) or otitis media with effusion (OME) without dizziness or vertigo, and discuss possible mechanisms. From February 2018 to November 2018, 34 consecutive patients with AOM or OME without dizziness were included. Nystagmus was examined with video Frenzel glasses. Of 34 adult AOM or OME patients without dizziness, nystagmus was observed in 28 patients (82%). In unilateral AOM or OME (n = 30), the most commonly observed nystagmus pattern was irritative-type direction-fixed nystagmus (n = 13), followed by paretic-type direction-fixed nystagmus (n = 8), and direction-changing positional nystagmus (n = 4). In bilateral AOM or OME (n = 4), direction-fixed nystagmus and direction-changing positional nystagmus were observed in two and one patients, respectively. Nystagmus was observed in as many as 82% of adult AOM or OME patients even though they did not complain of dizziness, and the pattern of nystagmus was either direction-fixed or direction-changing. Direct effect of inflammatory mediators penetrated from the middle ear and biochemical alteration in the inner ear fluids due to blood-perilymph barrier dysfunction may result in the presence of nystagmus in AOM or OME patients without dizziness.

A comparative study of two methods for treatment of benign paroxysmal positional vertigo in the emergency department

IntroductionPosterior canal benign paroxysmal positional vertigo (PC-BPPV) is considered the most common cause of peripheral vertigo in the emergency department (ED). Although the canalith repositioning maneuver (CRM) is the standard of care, the most effective method to deliver it in the ED has been poorly studied. ObjectiveTo compare two protocols of the Epley maneuver for the treatment of PC-BPPV. Patients and methodsWe prospectively recruited 101 patients with unilateral PC-BPPV on physical examination, randomizing them to either a single Epley maneuver (EM) (n = 46) or multiple maneuvers (n = 55) on the same visit. Measured outcomes included presence/absence of positional nystagmus, resolution of vertigo, and score on the dizziness handicap inventory (DHI) at follow-up evaluations. The DHI was stratified into mild (≤30) and moderate-severe (>30). ResultsNormalization of the Dix-Hallpike maneuver at day 5 was observed in 38% of the single EM group and 44.4% in the multiple EM group (p = 0.62). The DHI showed reduction from 42.2 (SD 18.4) to 31.9 (SD 23.7) in the single EM group and from 43.7 (SD 22.9) to 33.5 (SD 21.5) in the multiple EM group (p = 0.06). A higher number of patients improved from moderate-severe to mild DHI (p = 0.03) in the single EM group compared to the multi-EM group (p = 0.23). ConclusionThere was no statistically significant difference between performing a single EM versus multiple EMs for treatment of PC-BPPV in the emergency department. The single EM approach is associated with shorter physical contact between patients and examiner, which is logically safer in a pandemic context.

Clinical, oculographic, and vestibular test characteristics of vestibular migraine.

We characterise the history, vestibular tests, ictal and interictal nystagmus in vestibular migraine. We present our observations on 101 adult-patients presenting to an outpatient facility with recurrent spontaneous and/or positional vertigo whose final diagnosis was vestibular migraine (n = 27) or probable vestibular migraine (n = 74). Ictal and interictal video-oculography, caloric and video head impulse tests, vestibular-evoked myogenic potentials and audiometry were performed. Common presenting symptoms were headache (81.2%), spinning vertigo (72.3%), Mal de Débarquement (58.4%), and motion sensitivity (30.7%). With fixation denied, ictal and interictal spontaneous nystagmus was observed in 71.3 and 14.9%, and purely positional nystagmus in 25.8 and 55.4%. Spontaneous ictal nystagmus was horizontal in 49.5%, and vertical in 21.8%. Ictal spontaneous and positional nystagmus velocities were 5.3 ± 9.0°/s (range 0.0-57.4), and 10.4 ± 5.8°/s (0.0-99.9). Interictal spontaneous and positional nystagmus velocities were <3°/s in 91.8 and 23.3%. Nystagmus velocities were significantly higher when ictal (p < 0.001/confidence interval: 2.908‒6.733, p < 0.001/confidence interval: 5.308‒10.085). Normal lateral video head impulse test gains were found in 97.8% (mean gain 0.95 ± 0.12) and symmetric caloric results in 84.2% (mean canal paresis 7.0 ± 23.3%). Air- and bone-conducted cervical-vestibular-evoked myogenic potential amplitudes were symmetric in 88.4 and 93.4% (mean corrected amplitude 1.6 ± 0.7, 1.6 ± 0.8) with mean asymmetry ratios of 13.0 and 9.0%. Air- and bone-conducted ocular-vestibular-evoked myogenic potentials were symmetric in 67.7 and 97.2% (mean amplitude 9.2 ± 6.4 and 20.3 ± 12.8 µV) with mean asymmetry ratios of 15.7 and 9.9%. Audiometry was age consistent and symmetric in 85.5%. Vestibular migraine is characterised by low velocity ictal spontaneous nystagmus, which can be horizontal, vertical, or torsional, and normal audiovestibular test results.

Value of Vestibular Evoked Myogenic Potentials in IdentifyingDifferent Forms of Endolymphatic Hydrops: A Cross-Sectional Study

AbstractBackground: Meniere’s disease is idiopathic Endolym-phatic Hydrops. Vestibular evoked myogenic potential is aneurophysiological assessment technique that is used determinethe function of the otolith organs of the inner ear. Usingvestibular evoked myogenic potential tests may identify thedifferent forms of the Endolymphatic Hydrops.Aim of Study: The aim of this study is to explore the roleof vestibular evoked myogenic potentials (VEMP) in diagnosis of the different kinds of Meniere’s disease (MD).Patients and Methods: Three groups of patients that wereselected according to the diagnosis, definitive MD (DMD),cochlear MD (CMD) and recurrent vestibulopathy (RV) group.Basic audiological evaluation was carried out. It includedPure tone audiometry, speech audiometry, acoustic immittancetesting and electrocochleography. Otolith function assessmentwas carried out in the form of:Cervical VEMP (c-VEMP) and ocular VEMP (o-VEMP).Vestibular assessment was carried out: The test protocolincluded spontaneous nystagmus, gaze test, oculomotor tests,positioning test (Dixhallpike), positional nystagmus, andcaloric testing. The three groups were compared for all demo-graphic variables as well as clinic-pathologic variables, andtests results.Results: The overall sample was 40 cases; 13 with DMD,10 with CMD and 17 with RV. The mean age is variablebetween groups (p-value <0.001) with the highest in the DMDgroup (38.3±7.4 years) and the lowest in the CMD group (25.2±4.6 years). The male to female ratio is variable betweengroups of the study (p-value=0.03) with the highest ratio 9:4in the DMD group. There was a significant difference betweengroups (p < 0.001) regarding dizziness. Asymmetric responseof c-VEMP was seen in nine (9/13) (69.2%) of DMD cases, (14/17) (82.4%) of RV cases and only in three (3/10) (30%)of CMD cases, (p-value <0.001). Low amplitude of o-VEMPwas seen in (11/13) (84.6%) of DMD cases, (9/10) (90%) ofCMD cases, (15/17) (88.2%) of RV cases, and only in two (25%) of normal cases, (p-value=0.002). A significant differ-ence was found between definitive and cochlear Meniere's as regards o-VEMP inter-aural amplitude difference (IAD) (p-value=0.032) only. There was a significant positive strongcorrelation between age and EchoG sp/ap ratio left ear, o-VEMP IAD and o-VEMP left ear n1. In addition, there is asignificant positive weak correlation between duration andEchoG sp/ap ratio left ear and c-VEMP left ear n1.Conclusion: Asymmetric response of c-VEMP can beused as a diagnostic tool to differentiate different kinds ofMD: DMD, RV and CMD.

Significance of Pseudo-Conductive Hearing Loss and Positional Nystagmus for Perilymphatic Fistula: Are They Related to Third-Window Effects?

ObjectivesPatients’ clinical presentation is critical for identifying suspected perilymphatic fistula (PLF). The involvement of third-window lesions in the pathomechanism of PLF has been hypothesized. This study investigated the clinical features of PLF and the relationship of the third-window effect with PLF. MethodsSixty patients underwent surgical exploration for suspected PLF and the oval and round windows were reinforced. Clinical features including demographics, pure-tone audiometry (PTA), and videonystagmography were evaluated preoperatively and 1 month postoperatively. Surgical outcomes were analyzed according to the improvement of hearing and vestibular symptoms and signs. The conductive components of PTA (air-bone gap [ABG]) were measured, and the relationship between ABG closure after surgery and hearing improvement was analyzed. In addition, postoperative subjective dizziness was assessed by clinical interviews. Changes in positional nystagmus were analyzed according to ABG closure and hearing improvement.ResultsABG at lower frequencies (LFABG; 250 Hz, 500 Hz, 1,000 Hz) was present in 27 patients (45%). Postoperatively, PTA significantly improved after surgical repair. Among the patients with preoperative LFABG (n=27), 15 (55.5%) showed postoperative ABG closure and significant improvement in PTA at all frequencies compared with the patients without ABG closure (P=0.012). Subjective dizziness improved in 57 patients (93.3%). Positional nystagmus was found in 45 of 49 patients. Multiple canal involvement was more common than single canal involvement (67% vs. 33%). The horizontal semicircular canal was most commonly involved, followed by the posterior and anterior canals. Postoperatively, positional nystagmus disappeared, or the number of involved canals decreased in 22 of 34 patients (64.7%). ConclusionPseudo-conductive hearing loss at lower frequencies and positional nystagmus originating from multiple semicircular canals were common findings in PLF. Surgical reinforcement of the oval and round windows improved the hearing threshold accompanied by closure of ABG. A third-window lesion might explain these clinical features of PLF.

Dilatation of the Endolymphatic Space in the Ampulla of the Posterior Semicircular Canal: A New Clinical Finding Detected on Magnetic Resonance Imaging.

To investigate the clinical features of ears with dilatation of the endolymphatic space in the ampulla of the posterior semicircular canal on magnetic resonance imaging. Retrospective study. A university hospital. This study included 1,842 ears from 934 patients who underwent 3-T magnetic resonance imaging with gadolinium to investigate the presence of endolymphatic hydrops. Age, sex distribution, hearing thresholds on pure-tone audiometry, and vestibular symptoms were compared between cases of unilateral and bilateral dilatation of the endolymphatic space in the ampulla of the posterior semicircular canal. Forty-eight ears (17 men and 14 women; mean age 49.9 yrs) showed dilatation of the endolymphatic space in the ampulla of the posterior semicircular canal. Age and the rate of chronic sensorineural hearing loss were significantly higher in the unilateral group (14 ears) than in the bilateral group (34 ears). The average hearing thresholds and rates of vestibular symptoms reported did not differ between unilateral and bilateral cases, but some patients showed positional nystagmus. Dilatation of the endolymphatic space in the ampulla was observed selectively in the posterior semicircular canal, though its pathogenesis was not clear. Such dilatation is not usually accompanied by vestibular endolymphatic hydrops, and it may be a cause of vertigo and dizziness.

Central positional nystagmus in inferior cerebellar peduncle lesions: a case series.

We aimed to characterize the central positional nystagmus (CPN) observed in lesions involving the inferior cerebellar peduncle (ICP). We analyzed the clinical and neurotologic findings in six patients with an isolated unilateral ICP infarction that had been diagnosed at a university hospital in South Korea from 2003 to 2019. Patients usually presented with acute vestibular syndrome in isolation (4/6, 67%). Ipsilesional spontaneous nystagmus was observed in five while supine (5/6, 83%). Four (4/6, 67%) patients showed CPN which included apogeotropic (n = 3) or geotropic (n = 1) during head turning to either side while supine, and vertical nystagmus during straight-head hanging, Dix-Hallpike maneuvers, or up-righting (n = 3). Four patients showed contraversive ocular tilt reaction or tilt of the subjective visual vertical. Bedside and video head-impulse tests were normal in all patients. CPN is a usual finding in ICP lesions, and may be ascribed to damage of the fibers running from the nodulus/uvula onto the vestibular nucleus via the ICP.

Positional Nystagmus after Acute Vertiginous Attack in Meniere’s Disease

There have been no reports regarding nystagmus observed immediately after the end of an acute vertiginous attack in patients with Meniere’s disease. The aim of this study was to demonstrate positional direction-changing nystagmus in patients with Meniere’s disease, and to discuss the mechanism that underlies this nystagmus. Video-nystagmography was recorded in two patients with definite Meniere’s disease, who showed positional direction-changing nystagmus during the period immediately after a vertigo attack. In one patient, video-nystagmographic recording was conducted 5 h after an episode of vertigo attack, and it showed very weak, persistent positional geotropic direction-changing nystagmus. In the other patient, video-nystagmographic recording was conducted 23 h after an episode of vertigo attack, and it showed very weak, persistent positional apogeotropic direction-changing nystagmus. Our patients exhibited very weak, persistent positional direction-changing nystagmus, which was geotropic in one and apogeotropic in the other. This type of positional nystagmus has been reported in other inner ear disorders and it cannot be clearly explained by typical benign paroxysmal positional vertigo. The change in chemical composition and/or electrolyte concentration of the inner ear fluid, although still unclear, may underlie the production of this characteristic nystagmus in these patients.

A Show of Ewald's Law: I Horizontal Semicircular Canal Benign Paroxysmal Positional Vertigo.

Objective: To evaluate horizontal semicircular canal (HSC) effects according to Ewald's law and nystagmus characteristics of horizontal semicircular canal benign paroxysmal positional vertigo (HSC-BPPV) in the supine roll test.Methods: Patients with HSC-BPPV (n = 72) and healthy subjects (n = 38) were enrolled. Latency, duration, and intensity of nystagmus elicited by supine roll test were recorded using video nystagmography.Results: In patients with HSC-BPPV, horizontal nystagmus could be elicited by right/left head position (positional nystagmus) and during head-turning (head-turning nystagmus), and nystagmus direction was the same as that of head turning. Mean intensity values of head-turning nystagmus in HSC-BPPV patients were (44.70 ± 18.24)°/s and (44.65 ± 19.27)°/s on the affected and unaffected sides, respectively, which was not a significant difference (p = 0.980), while those for positional nystagmus were (40.81 ± 25.56)°/s and (17.69 ± 9.31)°/s (ratio, 2.59 ± 1.98:1), respectively, representing a significant difference (p < 0.0001). There was no positional nystagmus in 49 HSC-BPPV patients after repositioning treatment, nor in the 38 healthy subjects. No significant difference in head-turning nystagmus was detected in HSC-BPPV patients with or without repositioning.Conclusions: The direction and intensity of nystagmus elicited by supine roll test in patients with HSC-BPPV, was broadly consistent with the physiological nystagmus associated with a same HSC with single factor stimulus. Our findings suggest that HSC-BPPV can be a show of Ewald's law in human body.

Physical Therapy for Benign Positional Vertigo of Posterior Canal: The Role of Alternated Epley and Semont Maneuvers.

To investigate if alternated Epley (EP) and Semont (ST) maneuvers could be more effective than repetition of the same in benign paroxysmal positional vertigo of posterior semicircular canal (pBPPV). We retrospectively reviewed the outcome of pBPPV patients treated with a second maneuver for the persistence of positional nystagmus. Forty-seven patients underwent 2 STs, 64 with 2 EPs, and 71 EPs followed by ST. Videonystagmography and Dizziness Handicap Inventory (DHI) questionnaire were performed. Absence of positional nystagmus was achieved after 2 maneuvers in 136 patients with pBPPV: 65.9% in the ST group, 70.3% in the EP group, and 84.5% in the EP-ST group. Alternated EP and ST were significantly more effective than repeated ST (P = .03), while we found no significant difference when compared with repeated EP (P = .07). At 1-month follow-up, 12 patients showed persistent positional nystagmus without difference between groups. After 1 month, the 46 patients with negative outcome had significantly higher DHI values (P = .01) than other 136 patients with pBPPV. Alternated EP and ST seemed more effective than repeating the same maneuver in treating pBPPV, and this should be confirmed in prospective clinical studies. Resolution of nystagmus after maneuvers was fundamental to reduce handicap deriving from dizziness as reported in DHI.

Clinical Implications of Horizontal Beating Nystagmus Induced by Dix-Hallpike Test in the Diagnosis of Horizontal Canal Benign Paroxysmal Positional Vertigo.

The purpose of this study was to identify the diverse patterns of nystagmus during the Dix-Hallpike test (DHT) and analyze their clinical significance in horizontal canal benign paroxysmal positional vertigo (HC-BPPV). Retrospective medical records review. Two hundred ninety-five patients diagnosed with HC-BPPV. Various nystagmus patterns identified during the DHT in patients with HC-BPPV were analyzed. The correlation between the affected side of HC-BPPV and the direction of the horizontal beating nystagmus (HBN) during the DHT was also analyzed. The nystagmus pattern during the DHT in 128 patients with geotropic HC-BPPV demonstrated, direction-changing positional nystagmus on both sides in 48 (37.5%) patients, HBN toward one side in 25 (19.6%) patients, and no nystagmus in 55 (42.9%) patients. In 144 patients with apogeotropic HC-BPPV, 54 (37.5%) patients presented with direction-changing positional nystagmus on both sides, 27 (18.8%) patients presented with HBN toward one side, and 63 (43.7%) patients did not show nystagmus during the DHT. The direction of HBN provoked by the DHT was significantly correlated with the affected side in each subtype of HC-BPPV (geotropic type, p = 0.049; apogeotropic type, p = 0.040; respectively). More than half of the patients with HC-BPPV (56.6%) showed HBN during the DHT. When HBN was present during the DHT, it may provide a clue for determining the subtype and affected side in diagnosis of HC-BPPV before performing the supine roll test.

Clinical and pathogenetic aspects of positional nystagmus

Positional nystagmus (PN) is a heterogeneous clinical phenomenon. Most often it develops in benign positional paroxysmal vertigo as a result of otolithiasis. Rarely PN is observed in cases of lesion location in the cerebellum and brainstem. Recently a theory of light cupula was suggested to explain persisting geotropic PN. It explains the development of nystagmus by the changes in the ratio of the density of cupula to the density of endolymph, making the former sensitive to gravitational forces. Several theories were suggested: lighter cupula theory, heavier endolymph theory, theories of light debris and of density difference between perilymph and endolymph. However, the exact mechanism of light cupula syndrome is unclear. Clear diagnosis of the causes of PN requires detailed evaluation of neurological status with the use of diagnostic tests and additional research methods.

Diagnostic Value of Straight Head Hanging in Posterior Canal Benign Paroxysmal Positional Vertigo.

Background and PurposeTo determine the diagnostic value of straight head hanging (SHH) in benign paroxysmal positional vertigo involving the posterior semicircular canal (PC-BPPV).MethodsWe retrospectively included 62 patients (age=56.2±15.0 years, 47 female) with unilateral PC-BPPV who underwent both the Dix-Hallpike maneuver and SHH before receiving canalith repositioning therapy (CRT) between September 2017 and July 2020 at the Dizziness Center of Seoul National University Bundang Hospital in South Korea (16 patients, 25.8%) or the Neurology Outpatient Clinic of Aerospace Central Hospital in China (46 patients, 74.2%). SHH was performed before (n=29, group A) or after (n=33, group B) the Dix-Hallpike maneuver.ResultsTorsional upbeat nystagmus typical of PC-BPPV was induced during SHH in 52 (83.9%) patients, and the incidence of this type of positional nystagmus did not differ between the groups A and B (79.3% vs. 87.9%, p=0.569). The maximum slow-phase velocity of the induced upbeat nystagmus was higher during SHH than during the Dix-Hallpike maneuver toward the lesion side [range=2.0–60.0°/s (median=18.5°/s) vs. range=2.7–40.0°/s (median=13.4°/s), p<0.001]. Reversal of the positional nystagmus was observed upon resuming the sitting position after SHH in 47 (75.8%) patients and after the Dix-Hallpike maneuver in 54 (87.7%) patients, with no significant difference between the groups (p=0.082).ConclusionsSHH is effective for diagnosing PC-BPPV. Given its simplicity, SHH may be performed before the Dix-Hallpike maneuver, and CRT may be attempted thereafter when the typical positional nystagmus for unilateral PC-BPPV is induced during SHH.

Clinical Characteristics of Patients with Persistent Apogeotropic and Persistent Geotropic Direction-Changing Positional Nystagmus.

Background and PurposeThis study aimed to determine the clinical features, diagnosis, and treatment of patients with persistent geotropic (pG) and persistent apogeotropic (pAG) direction-changing positional nystagmus (DCPN).MethodsThis retrospective study included 30 patients with pG-DCPN and 44 patients with pAG-DCPN. All patients underwent neurological and neurotological examinations, including an evaluation of gaze-evoked nystagmus, eye-movement tests, and assessments of limb ataxia and balance, as well as magnetic resonance imaging to exclude central causes. The characteristics of positional nystagmus were detected using the supine roll test (SRT) and bow-and-lean test (BLT). The null point (NP) at which the nystagmus disappeared was determined. All patients were treated with the barbecue maneuver, and treatment efficacy was evaluated immediately, 1 week, and 1 month after treatment.ResultsThe history of diseases associated with atherosclerosis, peripheral vestibular disorders, otological disease, and migraine differed significantly between patients with pG-DCPN and pAG-DCPN. The affected sides of persistent horizontal DCPN can be determined using the SRT and the BLT, while determining the second NP and vestibular function as well as performing an audiological evaluation can be used to assist in identifying the affected side. The efficacy rates immediately and 1 week after treatment with the barbecue maneuver were higher in patients with pAG-DCPN than in patients with pG-DCPN.ConclusionspAG-DCPN was more compatible with the characteristics of cupulolithiasis, and pG-DCPN was more likely to be associated with a light cupula rather than canalolithiasis. pAG-DCPN was more likely to be accompanied by a disease associated with atherosclerosis, while pG-DCPN was often accompanied by autoimmune-related diseases and a history of migraine. The associations between pAG-DCPN, pG-DCPN, and the above-mentioned diseases need to be clarified further. The canalith-repositioning maneuver was effective in patients with pAG-DCPN and ineffective in patients with pG-DCPN, but most cases of pG-DCPN are self-limiting.

A Case of Persistent Direction-Changing Positional Nystagmus with Sudden Sensorineural Hearing Loss

A Case of Persistent Direction-Changing Positional Nystagmus with Sudden Sensorineural Hearing Loss

Vestibular Function Evaluation in Endemic Diseases Combat Agents

Introduction: Simultaneous exposure to certain chemical agents and noise may cause synergistic, additive or potentiating effects on the auditory and vestibular system. However, there is still a lack of studies investigating simultaneous exposure to pesticides and noise in the vestibular system. Purpose: To analyze the findings of the vestibular evaluation of endemic diseases combat agents when simultaneously exposed to pesticides and noise. Method: Thirty-three male pesticide-exposed and noise-fighting endemic diseases combat agents participated in the study. The age range was 48 to 67 years (mean = 56 years). All participants underwent vestibular examinations, such as positional nystagmus research, spontaneous nystagmus with open and closed eyes, semi-spontaneous nystagmus, optokinetic nystagmus, pendular screening, per rotatory, caloric tests and tonal audiometry. Data were analyzed by descriptive statistics. Results: Altered exams were presented in 36.4% of the cases. There was no statistically significant relationship between pesticide handling time and test results (p = 0.2825). The results of pure tone audiometry correlated significantly (p = 0.0494) with the vestibular exams, as participants who presented with worse hearing thresholds at the frequency of 4000 Hz in the right ear also presented altered results in the vestibular exam. Conclusion: The present study concluded that more than 1/3 of the studied population presented with vestibular dysfunction, which was related to anterior and posterior labyrinth alteration (Cochlear-Vestibular Syndrome). No central vestibular alteration was noted in this population.

Spontaneous Direction-Changing or Reversing Positional Nystagmus without Changing Head Position during Head-Roll/Head-Hanging Maneuvers: Biphasic Positional Nystagmus

Background and ObjectivesConflicting mechanisms have been reported about spontaneous reversal of positional nystagmus during head-roll maneuver in patients with benign paroxysmal positional vertigo (BPPV). The objective of this study is to review the reports about the characteristics and possible mechanisms of reversing positional nystagmus and to present seven new cases.Subjects and MethodsSeven cases (5 males, 2 females; 4 left-sided, 3 right-sided) were recruited among 732 patients with BPPV seen outpatient clinic between 2009 and 2019. Diagnosis of lateral canal canalolithiasis was confirmed when transient geotropic nystagmus was documented during head-roll test. Reversing positional nystagmus was analyzed in each case and clinical characteristics of the patients were documented.ResultsThe age of patients was ranging between 30 to 64 years (46.44±10.91). Duration of symptoms was short (21.34±19.74). Six of them had a story of head trauma. Initial latency was short. First, intense geotropic nystagmus was observed following provocative head-roll position on the affected side. There was short “silent phase”. Then, a longer second-phase of reversed nystagmus was noted. Total duration of nystagmus was 78.40±6.82 seconds. Maximal slow phase velocity was 24.05±6.34 deg/sec. All patients were cured with barbeque maneuver.ConclusionsIpsilateral reversing positional nystagmus during head-roll maneuver is due to lateral canal canalolithiasis. Mechanism is likely to be due to endolymphatic double flow. Bilateral cases may be due to simultaneous co-existence of canalolithiasis and cupulolithiasis. Longer recording of nystagmus is recommended not to miss the cases with spontaneous direction-changing positional nystagmus.

Nystagmus characteristics of healthy controls.

BACKGROUND:Healthy controls exhibit spontaneous and positional nystagmus which needs to be distinguished from pathological nystagmus.OBJECTIVE:Define nystagmus characteristics of healthy controls using portable video-oculography.METHODS:One-hundred and one asymptomatic community-dwelling adults were prospectively recruited. Participants answered questions regarding their audio-vestibular and headache history and were sub-categorized into migraine/non-migraine groups. Portable video-oculography was conducted in the upright, supine, left- and right-lateral positions, using miniature take-home video glasses.RESULTS:Upright position spontaneous nystagmus was found in 30.7% of subjects (slow-phase velocity (SPV)), mean 1.1±2.2 degrees per second (°/s) (range 0.0 – 9.3). Upright position spontaneous nystagmus was horizontal, up-beating or down-beating in 16.7, 7.9 and 5.9% of subjects. Nystagmus in at least one lying position was found in 70.3% of subjects with 56.4% showing nystagmus while supine, and 63.4% in at least one lateral position. While supine, 20.8% of subjects showed up-beating nystagmus, 8.9% showed down-beating, and 26.7% had horizontal nystagmus. In the lateral positions combined, 37.1% displayed horizontal nystagmus on at least one side, while 6.4% showed up-beating, 6.4% showed down-beating. Mean nystagmus SPVs in the supine, right and left lateral positions were 2.2±2.8, 2.7±3.4, and 2.1±3.2°/s. No significant difference was found between migraine and non-migraine groups for nystagmus SPVs, prevalence, vertical vs horizontal fast-phase, or low- vs high-velocity nystagmus (<5 vs > 5°/s).CONCLUSIONS:Healthy controls without a history of spontaneous vertigo show low velocity spontaneous and positional nystagmus, highlighting the importance of interictal nystagmus measures when assessing the acutely symptomatic patient.

Direction-fixed positional nystagmus following head-roll testing: how is it related with a vestibular pathology?

ObjectiveThe goal of this study is to analyze the clinical view of patients with direction-fixed positional nystagmus (DFPN) following head-roll maneuver. MethodsSixty patients with DFPN were reviewed retrospectively. Patients were categorized into 3 groups according to the direction of nystagmus based on rotation side. Associated problems were documented, and cumulative data were compared between groups. One-way analysis of variance (ANOVA test) was used for statistical analysis (P < 0.05). ResultsThirty-three patients (55%) had stronger nystagmus beating towards the direction of head-roll (Group-A). Three patients developed geotropic LC-BPPV. Fourteen patients had inner ear disease. Sixteen patients (27%) had stronger nystagmus beating against the direction of head roll (Group-B). Nine patients had inner ear disease. None of the patients tested with head-shaking had change of direction of nystagmus. Eleven patients (18%) had DFPN with equal velocity during right or left head-roll maneuver (Group-C). Of those, nine patients had inner ear disease. None of the patients had change of direction of nystagmus. Comparison of the incidence of associated problems (migraine, vestibular neuronitis, Meniere’s disease etc.) in each group was not statistically significant (P˃0.05). ConclusionPatients with DFPN should be followed for a possibility of vestibular pathology since vestibular problem was documented for more than half of the patients in the follow-up. On the other hand, DFPN could be related with a temporary reason (thermal, physical or drug effect etc.) in some patients who do not exhibit any associated disease. Head-shaking testing is recommended to expose the lateral canal BPPV. But the incidence is low.

Effect of the Epley Maneuver and Brandt-Daroff Exercise on Benign Paroxysmal Positional Vertigo Involving the Posterior Semicircular Canal Cupulolithiasis: A Randomized Clinical Trial.

Objective: To investigate the therapeutic efficacies of the Epley maneuver and Brandt-Daroff (BD) exercise in patients with benign paroxysmal positional vertigo involving the posterior semicircular canal cupulolithiasis (PC-BPPV-cu).Methods: We conducted a randomized clinical trial to evaluate the therapeutic effect of the Epley maneuver and BD exercise in patients with PC-BPPV-cu. Patients were randomly assigned to undergo the Epley maneuver (n = 29) or BD exercise (n = 33). The primary outcome was an immediate resolution of positional nystagmus within 1 h after a single treatment of each maneuver on the visit day. Secondary outcomes included the resolution of positional nystagmus at 1 week, the change of maximal slow phase velocity (mSPV) of positional nystagmus, and dizziness handicap inventory (DHI) immediately and at 1 week.Results: Immediate resolution occurred in none of 29 patients in the Epley maneuver group and only 1 of 33 patients in the BD exercise group. The Epley maneuver and BD exercise had an equivalent effect at 1 week in treating PC-BPPV-cu in terms of resolving positional nystagmus (48 vs. 36%, p = 0.436) and the decrease of mSPV and DHI.Conclusion: Neither the Epley maneuver nor BD exercise has an immediate therapeutic effect in treating PC-BPPV-cu. Clear classification of PC-BPPV should be required at the time of different pathology and different treatment response.