19 results on '"Nham, B."'
Search Results
2. Capturing nystagmus in the emergency room: posterior circulation stroke versus acute vestibular neuritis
- Author
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Nham, B., primary, Akdal, G., additional, Young, A. S., additional, Özçelik, P., additional, Tanrıverdizade, T., additional, Ala, R. T., additional, Bradshaw, A. P., additional, Wang, C., additional, Men, S., additional, Giarola, B. F., additional, Black, D. A., additional, Thompson, E. O., additional, Halmagyi, G. M., additional, and Welgampola, M. S., additional
- Published
- 2022
- Full Text
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3. Vestibular migraine presenting with acute peripheral vestibulopathy: Clinical, oculographic and vestibular test profiles
- Author
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Calic, Z, Nham, B, Taylor, RL, Young, AS, Bradshaw, AP, McGarvie, LM, Colebatch, JG, Cordato, D, Cappelen-Smith, C, Welgampola, MS, Calic, Z, Nham, B, Taylor, RL, Young, AS, Bradshaw, AP, McGarvie, LM, Colebatch, JG, Cordato, D, Cappelen-Smith, C, and Welgampola, MS
- Abstract
To describe clinical, oculographic and vestibular test profiles in patients with vestibular migraine (VM) who presented with acute peripheral vestibulopathy. VM was diagnosed according to Bárány Society or Neuhauser criteria. Neuro-otological examination, video-head impulse tests (v-HIT), cervical and ocular vestibular-evoked myogenic potentials (cVEMP/oVEMP), subjective visual horizontal (SVH) and audiometry were undertaken. Ten patients presented with prolonged vertigo. All had primary position unidirectional horizontal spontaneous nystagmus (mean slow-phase velocity 9.6 ± 7.0°). Horizontal canal vestibulo-ocular reflex was reduced in all (mean gain 0.54 ± 0.2) with refixation saccades (cumulative amplitude 6.4 ± 3.2°). Abnormality rates for cVEMP, oVEMP and SVH were 30%, 80%, 78%, respectively. Magnetic resonance imaging brain was normal in all patients. Patients were followed up over 6 months to 8 years with no change in the final diagnosis. VM can rarely present as an acute peripheral vestibulopathy with findings that mimic vestibular neuritis and should be considered in the differential diagnosis of acute prolonged vertigo.
- Published
- 2020
4. Seesaw Nystagmus and Internuclear Ophthalmoplegia From Paramedian Pontine Infarction.
- Author
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Nham B, Morrison M, and Welgampola MS
- Abstract
Competing Interests: The authors report no conflicts of interest.
- Published
- 2024
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5. Machine learning models help differentiate between causes of recurrent spontaneous vertigo.
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Wang C, Young AS, Raj C, Bradshaw AP, Nham B, Rosengren SM, Calic Z, Burke D, Halmagyi GM, Bharathy GK, Prasad M, and Welgampola MS
- Subjects
- Humans, Female, Male, Middle Aged, Adult, Diagnosis, Differential, Aged, Recurrence, Machine Learning, Migraine Disorders diagnosis, Migraine Disorders physiopathology, Vertigo diagnosis, Vertigo physiopathology, Meniere Disease diagnosis, Meniere Disease physiopathology
- Abstract
Background: Vestibular migraine (VM) and Menière's disease (MD) are two common causes of recurrent spontaneous vertigo. Using history, video-nystagmography and audiovestibular tests, we developed machine learning models to separate these two disorders., Methods: We recruited patients with VM or MD from a neurology outpatient facility. One hundred features from six "feature subsets": history, acute video-nystagmography and four laboratory tests (video head impulse test, vestibular-evoked myogenic potentials, caloric testing and audiogram) were used. We applied ten machine learning algorithms to develop classification models. Modelling was performed using three "tiers" of data availability to simulate three clinical settings. "Tier 1" used all available data to simulate the neuro-otology clinic, "Tier 2" used only history, audiogram and caloric test data, representing the general neurology clinic, and "Tier 3" used history alone as occurs in primary care. Model performance was evaluated using tenfold cross-validation., Results: Data from 160 patients with VM and 114 with MD were used for model development. All models effectively separated the two disorders for all three tiers, with accuracies of 85.77-97.81%. The best performing algorithms (AdaBoost and Random Forest) yielded accuracies of 97.81% (95% CI 95.24-99.60), 94.53% (91.09-99.52%) and 92.34% (92.28-96.76%) for tiers 1, 2 and 3. The best feature subset combination was history, acute video-nystagmography, video head impulse test and caloric testing, and the best single feature subset was history., Conclusions: Machine learning models can accurately differentiate between VM and MD and are promising tools to assist diagnosis by medical practitioners with diverse levels of expertise and resources., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.)
- Published
- 2024
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6. The role of cochlear and vestibular afferents in long-latency cervical vestibular evoked myogenic potentials.
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Hope SJ, Govender S, Taylor RL, Kwok BYC, Pogson JM, Nham B, Wang C, Young AS, Dyball AC, Kong JHK, Welgampola MS, and Rosengren SM
- Abstract
Objective: To examine the origin of cervical vestibular evoked myogenic potential (cVEMP) late waves (n34-p44) elicited with air-conducted click stimuli., Design: Using a retrospective design, cVEMPs from normal volunteers were compared to those obtained from patients with vestibular and auditory pathologies., Study Sample: (1) Normal volunteers (n = 56); (2) severe-to-profound sensorineural hearing loss (SNHL) with normal vestibular function (n = 21); (3) peripheral vestibular impairment with preserved hearing (n = 16); (4) total vestibulocochlear deficit (n = 23)., Results: All normal volunteers had ipsilateral-dominant early p13-n23 peaks. Late peaks were present bilaterally in 78%. The p13-n23 response was present in all patients with SNHL but normal vestibular function, and 43% had late waves. Statistical comparison of these patients to a subset of age-matched controls showed no significant difference in the frequencies, amplitudes or latencies of their ipsilateral early and late peaks. cVEMPs were absent in all patients with vestibular impairment., Conclusion: The presence of long-latency cVEMP waves was not dependent on the integrity of sensorineural hearing pathways, but instead correlated with intact vestibular function. This finding conflicts with the view that these late waves are cochlear in origin, and suggests that vestibular afferents may assume a more prominent role in their generation.
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- 2024
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7. Subjective visual horizontal correlates better with ocular than with cervical vestibular evoked myogenic potentials.
- Author
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Argaet EC, Kwok BYC, Bradley J, Young AS, Nham B, Calic Z, Taylor RL, Pogson JM, Reid N, Kong JHK, Flanagan S, Halmagyi GM, Rosengren SM, and Welgampola MS
- Subjects
- Humans, Retrospective Studies, Eye, Vestibular Evoked Myogenic Potentials physiology, Vestibular Neuronitis diagnosis, Meniere Disease diagnosis, Hearing Loss, Sensorineural
- Abstract
Objective: To examine the relationship between widely used otolith function tests: the Subjective Visual Horizontal (SVH) and Vestibular Evoked Myogenic Potentials (VEMP)., Methods: A retrospective analysis was performed on 301 patients who underwent SVH, ocular and cervical VEMP (oVEMP and cVEMP) tests on the same day. Correlations between the mean SVH tilt and amplitude asymmetry ratios for bone-conducted (BC) oVEMP and air-conducted (AC) cVEMP were examined. Diagnoses included vestibular neuritis, stroke, vestibular migraine, Meniere's disease, sudden sensorineural hearing loss (SSNHL) and vestibular schwannoma., Results: SVH results were concordant with the oVEMP in 64% of cases and the cVEMP in 51%. Across all patients, SVH demonstrated a significant moderate correlation with BC oVEMP amplitude asymmetry ratios (r = 0.55, p < 0.001) and a weak correlation with AC cVEMP amplitude asymmetry ratios (r = 0.35, p < 0.001). A stronger correlation between SVH and oVEMPs was observed in patients with vestibular neuritis (r = 0.67, p < 0.001) and SSNHL (r = 0.76, p = 0.001)., Conclusions: SVH correlates better with oVEMP than cVEMP symmetry., Significance: This finding reinforces the hypothesis of a common utricular origin for both SVH and oVEMPs which is distinct from the saccular origin of cVEMPs., Competing Interests: Declaration of interest Allison Young, Benjamin Nham and Belinda Kwok received funding through the University of Sydney Postgraduate Award. Miriam Welgampola is supported by grants from the National Health and Medical Research Council and Garnett Passe and Rodney Williams Memorial Foundation. All other authors report no disclosures relevant to the study., (Copyright © 2023 International Federation of Clinical Neurophysiology. All rights reserved.)
- Published
- 2023
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8. The Relationship between the Subjective Visual Horizontal and Ocular Vestibular Evoked Myogenic Potentials in Acute Vestibular Neuritis.
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Hannigan IP, Nham B, Wang C, Rosengren SM, Kwok BYC, McGarvie LA, Reid NM, Curthoys IS, Halmágyi GM, and Welgampola MS
- Subjects
- Humans, Retrospective Studies, Eye, Vestibular Evoked Myogenic Potentials physiology, Vestibular Neuronitis diagnosis, Vestibule, Labyrinth
- Abstract
Object: Vestibular evoked myogenic potentials (VEMPs) and the subjective visual horizontal (SVH) (or vertical [SVV]) have both been considered tests of otolith function: ocular-VEMPs (oVEMPs) utricular function, cervical VEMPs (cVEMPs) saccular function. Some studies have reported association between decreased oVEMPs and SVH, whereas others have not., Design: A retrospective study of test results., Setting: A tertiary, neuro-otology clinic, Royal Prince Alfred Hospital, Sydney, Australia., Method: We analyzed results in 130 patients with acute vestibular neuritis tested within 5 days of onset. We sought correlations between the SVH, oVEMPs, and cVEMPs to air-conducted (AC) and bone-conducted (BC) stimulation., Results: The SVH deviated to the side of lesion, in 123 of the 130 AVN patients, by 2.5 to 26.7 degrees. Ninety of the AVN patients (70%) had abnormal oVEMPs to AC, BC or both stimuli, on the AVN side (mean asymmetry ratio ± SD [SE]): (64 ± 45.0% [3.9]). Forty-three of the patients (35%) had impaired cVEMPs to AC, BC or both stimuli, on the AVN side, [22 ± 41.6% (4.1)]. The 90 patients with abnormal oVEMP values also had abnormal SVH. Correlations revealed a significant relationship between SVH offset and oVEMP asymmetry (r = 0.80, p < 0.001) and a weaker relationship between SVH offset and cVEMP asymmetry (r = 0.56, p < 0.001)., Conclusions: These results indicate that after an acute unilateral vestibular lesion, before there has been a chance for vestibular compensation to occur, there is a significant correlation between the SVH, and oVEMP results. The relationship between SVH offset and oVEMP amplitude suggests that both tests measure utricular function., Competing Interests: The authors disclose no conflicts of interest ., (Copyright © 2023, Otology & Neurotology, Inc.)
- Published
- 2023
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9. Modern vestibular tests can accurately separate stroke and vestibular neuritis.
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Nham B, Wang C, Reid N, Calic Z, Kwok BYC, Black DA, Bradshaw A, Halmagyi G, and Welgampola MS
- Subjects
- Humans, Vertigo diagnosis, Saccades, Head Impulse Test methods, Vestibular Neuronitis diagnosis, Stroke complications, Stroke diagnosis, Nystagmus, Pathologic diagnosis, Nystagmus, Pathologic etiology, Neuritis
- Abstract
Objectives: To separate posterior-circulation stroke (PCS) and vestibular-neuritis (VN) using quantitative vestibular tests., Methods: Patients were prospectively recruited from the emergency room within 72 h of presentation. Video-nystagmography (VNG), three-dimensional video head-impulse testing (vHIT), vestibular-evoked myogenic potentials (VEMPs), and subjective visual-horizontal (SVH) were performed., Results: There were 128 PCS and 134 VN patients. Common stroke-territories were: posterior-inferior cerebellar artery, basilar-perforators, multi-territory and anterior-inferior cerebellar artery (41.4%, 21.1%, 14.1%, 7.8%). VN included superior, inferior and pan-neuritis (53.3%, 4.2%, and 41.5%). Most VN and stroke patients presented with acute vestibular syndrome (96.6%, 61.7%). In VN, we recorded horizontal (98.5%) or vertical/torsional spontaneous nystagmus (1.5%) and in PCS, absent-nystagmus (53.9%), horizontal (32%) or vertical/torsional (14.1%) nystagmus. The mean slow-phase velocity of horizontal nystagmus was faster in VN than PCS (11.8 ± 7.2 and 5.2 ± 3.0°/s, p < 0.01). Ipsilesional horizontal-canal (HC) vHIT-gain was lower in VN than in stroke (0.47 ± 0.24, 0.92 ± 0.20, p < 0.001). Ipsilesional catch-up saccades occurred earlier, and their amplitude, prevalence, and velocity were greater in VN than PCS (p < 0.01). Ipsilesional SVH deviation > 2.5° occurred more often in VN than in stroke (97.6% and 24.3%, p < 0.01). Abnormal bone-conducted ocular-VEMP asymmetry ratio was more common in VN than PCS (50% and 14.4%, p < 0.01). Using the ten best discriminators (VNG, vHIT, SVH, and oVEMP metrics), VN was separated from PCS with a sensitivity of 92.9% and specificity of 89.8%. Adding VNG and vHIT to the bedside head-impulse-nystagmus-and-test-of-skew (HINTS) test enhanced sensitivity and specificity from 95.3% and 63.4% to 96.5% and 80.6%., Conclusion: Quantitative vestibular testing helps separate stroke from vestibular neuritis and, when used, could improve diagnostic accuracy in the emergency room., (© 2022. Crown.)
- Published
- 2023
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10. Clinical, oculographic and vestibular test characteristics of Ménière's disease.
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Young AS, Nham B, Bradshaw AP, Calic Z, Pogson JM, Gibson WP, Halmagyi GM, and Welgampola MS
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- Head Impulse Test, Humans, Vertigo diagnosis, Meniere Disease diagnosis, Nystagmus, Pathologic diagnosis, Vestibular Evoked Myogenic Potentials
- Abstract
Seventy Ménière's disease (MD) patients with spontaneous vertigo (100%), unilateral aural fullness (57.1%), tinnitus (78.6%), and subjective hearing loss (75.7%) self-recorded nystagmus during their episodes of vertigo using portable video oculography goggles. All demonstrated ictal spontaneous nystagmus, horizontal in 94.3% (n = 66) and vertical in 5.7% (n = 4), with a mean slow-phase velocity (SPV) of 42.8 ± 31.1°/s (range 5.3-160.1). Direction reversal of spontaneous horizontal nystagmus was captured in 58.6%, within the same episode in 34.3%, and over different days in 24.3%. In 18.6%, we observed ipsiversive then contraversive nystagmus, and in 12.9% contraversive to ipsiversive direction reversal. Ictal nystagmus SPV (42.8 ± 31.1°/s) was significantly faster than interictal (1.4 ± 3.1°/s, p < 0.001, CI 34.277-48.776). Compared to age-matched healthy controls, interictal video head impulse test gains in MD ears were significantly lower, cumulative and first saccade (S1) amplitudes were significantly larger, and S1 peak velocities were significantly faster (p = 0.038/0.019/0.008/ < 0.001, CI 0.002-0.071/0.130-1.444/0.138-0.909/14.614-41.506). Audiometry showed asymmetrically increased thresholds in 100% of MD ears (n = 70). Significant caloric, air-conducted (AC) cervical vestibular-evoked myogenic potential (VEMP), and AC ocular VEMP asymmetries were found in 61.4, 37.9, and 44.4% of patients (MD ear reduced). Transtympanic electrocochleography tested in 36 ears (23 patients) showed 81.8% of MD ears had a positive result for hydrops (either a summating potential at 1/2 kHz < - 6 µV, or an SP/AP ratio > 40%). Using ictal nystagmus findings of SPV > 12°/s, and a caloric canal paresis > 25%, we correctly separated a diagnosis MD from Vestibular Migraine with a sensitivity and specificity of 95.7% and 85.1% (CI 0.89-0.97)., (© 2021. Springer-Verlag GmbH Germany, part of Springer Nature.)
- Published
- 2022
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11. Capturing vertigo in the emergency room: three tools to double the rate of diagnosis.
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Nham B, Reid N, Bein K, Bradshaw AP, McGarvie LA, Argaet EC, Young AS, Watson SR, Halmagyi GM, Black DA, and Welgampola MS
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- Benign Paroxysmal Positional Vertigo diagnosis, Emergency Service, Hospital, Head Impulse Test, Humans, Meniere Disease diagnosis, Nystagmus, Pathologic diagnosis, Vestibular Neuronitis
- Abstract
Objective: Many patients attending the emergency room (ER) with vertigo, leave without a diagnosis. We assessed whether the three tools could improve ER diagnosis of vertigo., Methods: A prospective observational study was undertaken on 539 patients presenting to ER with vertigo. We used three tools: a structured-history and examination, nystagmus video-oculography (VOG) in all patients, additional video head-impulse testing (vHIT) for acute-vestibular-syndrome (AVS)., Results: In the intervention-group (n = 424), case-history classified AVS in 34.9%, episodic spontaneous-vertigo (ESV 32.1%), and episodic positional-vertigo (EPV 22.6%). In AVS, we employed "Quantitative-HINTS plus" (Head-Impulse, Nystagmus and Test-of-Skew quantified by vHIT and VOG, audiometry) to identify vestibular-neuritis (VN) and stroke (41.2 and 31.1%). vHIT gain ≤ 0.72, catch-up saccade amplitude > 1.4
○ , saccade-frequency > 154%, and unidirectional horizontal-nystagmus, separated stroke from VN with 93.1% sensitivity and 88.5% specificity. In ESV, 66.2 and 14% were diagnosed with vestibular migraine and Meniere's Disease by using history and audiometry. Horizontal-nystagmus velocity was lower in migraine 0.4 ± 1.6○ /s than Meniere's 5.7 ± 5.5○ /s (p < 0.01). In EPV, benign positional vertigo (BPV) was identified in 82.3% using VOG. Paroxysmal positional-nystagmus lasting < 60 s separated BPV from non-BPV with 90% sensitivity and 100% specificity. In the control group of ER patients undergoing management-as-usual (n = 115), diagnoses included BPV (38.3%) and non-specific vertigo (41.7%). Unblinded assessors reached a final diagnosis in 90.6 and 30.4% of the intervention and control groups. Blinded assessors provided with the data gathered from each group reached a diagnosis in 86.3 and 41.1%., Conclusion: Three tools: a structured-assessment, vHIT and VOG doubled the rate of diagnosis in the ER., (© 2021. Springer-Verlag GmbH Germany, part of Springer Nature.)- Published
- 2022
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12. Clinical, oculographic, and vestibular test characteristics of vestibular migraine.
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Young AS, Nham B, Bradshaw AP, Calic Z, Pogson JM, D'Souza M, Halmagyi GM, and Welgampola MS
- Subjects
- Adult, Humans, Nystagmus, Physiologic, Vestibular Function Tests, Migraine Disorders diagnosis, Nystagmus, Pathologic diagnosis, Vertigo
- Abstract
Background: We characterise the history, vestibular tests, ictal and interictal nystagmus in vestibular migraine., Method: 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., Results: 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%., Conclusion: Vestibular migraine is characterised by low velocity ictal spontaneous nystagmus, which can be horizontal, vertical, or torsional, and normal audiovestibular test results.
- Published
- 2021
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13. Contralesional subjective visual horizontal predicts endolymphatic hydrops.
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Nham B, Welgampola MS, and Halmagyi GM
- Subjects
- Adult, Aged, Caloric Tests, Diagnosis, Differential, Endolymphatic Hydrops physiopathology, Female, Humans, Male, Meniere Disease diagnosis, Middle Aged, Nystagmus, Pathologic physiopathology, Retrospective Studies, Endolymphatic Hydrops diagnosis, Vestibular Function Tests
- Abstract
Background: The subjective visual horizontal (SVH) is a test of utricular function that assesses conjugate ocular torsion which is a component of the ocular tilt reaction (OTR). In unilateral destructive peripheral vestibular lesions, the OTR and so the SVH tilt is usually ipsiversive. Aims/objective: Our study aimed to profile the causes of a contraversive SVH tilt in patients with a confirmed unilateral peripheral vestibular deficit. Materials and methods: The clinical records, nystagmus and vestibular investigation characteristics of 52 patients with a unilateral canal paresis (CP) on caloric of ≥30%, a contraversive SVH tilt of ≥4 degrees and at least one pure tone audiometry were retrospectively analysed. Results: The most common diagnosis of patients ( n = 39) with a contraversive SVH and ipsilesional CP was endolymphatic hydrops: 35 (67.3%) had Meniere's disease (MD) and 4 (7.7%) had delayed endolymphatic hydrops (DEH). The remaining 13 (25%) of cases had other peripheral aetiologies or an unknown diagnosis. 16 (30.8%) patients had ictal spontaneous nystagmus at the time of SVH or caloric testing. Conclusions and significance: A contraversive SVH with unilateral CP suggests endolymphatic hydrops.
- Published
- 2020
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14. Separating posterior-circulation stroke from vestibular neuritis with quantitative vestibular testing.
- Author
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Calic Z, Nham B, Bradshaw AP, Young AS, Bhaskar S, D'Souza M, Anderson CS, Cappelen-Smith C, Cordato D, and Welgampola MS
- Subjects
- Diagnosis, Differential, Head Impulse Test standards, Humans, Otolithic Membrane physiopathology, Reflex, Vestibulo-Ocular, Sensitivity and Specificity, Stroke physiopathology, Vestibular Evoked Myogenic Potentials, Vestibular Neuronitis physiopathology, Head Impulse Test methods, Stroke diagnosis, Vestibular Neuronitis diagnosis
- Abstract
Objective: To separate vestibular neuritis (VN) from posteriorcirculation stroke (PCS) using quantitative tests of canal and otolith function., Methods: Video Head-Impulse tests (vHIT) were used to assess all three semicircular canal pairs; vestibulo-ocular reflex (VOR) gain and saccade metrics were examined. Cervical and ocular-Vestibular-Evoked Myogenic Potentials (c- and oVEMP) and Subjective Visual Horizontal (SVH) were used to assess otolith function., Results: For controls (n = 40), PCS (n = 22), and VN (n = 22), mean horizontal-canal VOR-gains were 0.96 ± 0.1, 0.85 ± 0.3 and 0.40 ± 0.2, refixation-saccade prevalence was 71.9 ± 41, 90.7 ± 57, 209.2 ± 62 per 100 impulses and cumulative-saccade amplitudes were 0.9 ± 0.4°, 2.4 ± 2.2°, 8.0 ± 3.5°. Abnormality-rates for cVEMP, oVEMP and SVH were 38%, 9%, 72% for PCS, and 43%, 50%, 91% for VN. A gain ≤0.68, refixation-saccade prevalence of ≥135% and cumulative-saccade amplitudes ≥5.3° separated VN from PCS with sensitivities of 95.5%, 95.5%, and 81.8%, and specificities of 68.2%, 86.4% and 95.5%. VOR-gain and saccade prevalence when combined, separated VN from PCS with a sensitivity and specificity of 90.9%. Abnormal oVEMP asymmetry-ratios were of low sensitivity (50%) but high specificity (90.9%) for separating VN from PCS., Conclusion: vHIT provided the best separation of VN from PCS. VOR-gain, refixation-saccade prevalence and amplitude were effective discriminators of VN from PCS., Significance: vHIT and oVEMP could assist early identification of the aetiology of Acute Vestibular Syndrome in the Emergency Room., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)
- Published
- 2020
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15. A treatable cause of vertigo.
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Nham B, Young AS, Garsia R, Halmagyi GM, and Welgampola MS
- Subjects
- Aged, Autoimmune Diseases complications, Autoimmune Diseases therapy, Diagnosis, Differential, Eye Movements physiology, Hearing Loss, Sensorineural etiology, Hearing Loss, Sensorineural therapy, Humans, Labyrinth Diseases complications, Labyrinth Diseases therapy, Male, Treatment Outcome, Vertigo etiology, Vertigo therapy, Autoimmune Diseases diagnosis, Hearing Loss, Sensorineural diagnosis, Labyrinth Diseases diagnosis, Vertigo diagnosis
- Abstract
Competing Interests: Competing interests: None declared.
- Published
- 2020
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16. Vestibular-Evoked Myogenic Potential Testing in Vestibular Localization and Diagnosis.
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Taylor RL, Welgampola MS, Nham B, and Rosengren SM
- Subjects
- Humans, Vestibular Diseases diagnosis, Vestibular Diseases physiopathology, Vestibular Evoked Myogenic Potentials physiology
- Abstract
Vestibular-evoked myogenic potentials (VEMPs) are short-latency, otolith-dependent reflexes recorded from the neck and eye muscles. They are widely used in neuro-otology clinics as tests of otolith function. Cervical VEMPs are recorded from the neck muscles and reflect predominantly saccular function, while ocular VEMPs are reflexes of the extraocular muscles and reflect utricular function. They have an important role in the diagnosis of superior canal dehiscence syndrome and provide complementary information about otolith function that is useful in the diagnosis of other vestibular disorders. Like other evoked potentials, they can provide important localizing information about lesions that may occur along the VEMP pathway. This review will describe the VEMP abnormalities seen in common disorders of the vestibular system and its pathways., Competing Interests: None., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)
- Published
- 2020
- Full Text
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17. Hunting for a cause of painful diplopia.
- Author
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Nham B
- Subjects
- Humans, Diplopia, Pain
- Published
- 2019
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18. Why medically unexplained symptoms and health anxiety don't need to make your heart sink.
- Author
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Nham B and Williard A
- Subjects
- Anxiety, Anxiety Disorders, Humans, Medically Unexplained Symptoms
- Published
- 2018
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19. Listeria rhomboencephalomyelitis complicated by hemorrhagic transformation.
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Nham B, Baskin J, and Choong H
- Subjects
- Cerebral Hemorrhage diagnostic imaging, Encephalomyelitis diagnostic imaging, Female, Humans, Magnetic Resonance Imaging, Middle Aged, Cerebral Hemorrhage complications, Encephalomyelitis etiology, Rhombencephalon pathology
- Published
- 2017
- Full Text
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