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Original Articles
Development of An Algorithm for Slippage-Induced Motion Artifacts Reduction in Video-Nystagmography
Yerin Lee, Young Joon Seo, Sejung Yang
Res Vestib Sci. 2022;21(4):104-110.   Published online December 15, 2022
DOI: https://doi.org/10.21790/rvs.2022.21.4.104
  • 1,948 View
  • 58 Download
AbstractAbstract PDF
Objectives
The slippage of the video-nystagmography devices causes motion artifacts in the trajectory of the pupil and thus results in distortion in the nystagmus waveform. In this study, the moving average was proposed to reduce slippage-induced motion artifacts from the real-world data obtained in the field.
Methods
The dataset consists of an infrared video of positional tests performed on eight patients with a lateral semicircular canal benign paroxysmal positional vertigo. The trajectories of the pupil were obtained from the video with binarization, morphological operation, and elliptical fitting algorithm. The acquired data was observed and the section where the slippage occurred was labeled by an otolaryngologist. The moving average with windows of various lengths was calculated and subtracted from the original signal and evaluated to find the most adequate parameter to reduce the motion artifact.
Results
The period of nystagmus in the given data was found to be ranged from 0.01 to 4 seconds. The slippages that appeared in the data can be categorized into fast and slow slippages. The length, distance, and speed of trajectories in the slippage ranges were also measured to find the characteristics of the motion artifact in video-nystagmography data. The shape of the nystagmus waveform was preserved, and the motion artifacts were reduced in both types of slippages when the length of the window in moving average was set to 1 second.
Conclusions
The algorithm developed in this study is expected to minimize errors caused by slippage when developing a diagnostic algorithm that can assist clinicians.
Assessment of the Vestibuloocular Reflex in Patients with Unilateral Chronic Middle Ear Disease Using the Video Head Impulse Test: A Preliminary Study
Gi-Sung Nam, Wonyong Baek, Sung-Il Cho
Res Vestib Sci. 2022;21(3):80-85.   Published online September 15, 2022
DOI: https://doi.org/10.21790/rvs.2022.21.3.80
  • 2,608 View
  • 53 Download
AbstractAbstract PDF
Objectives
This study aims to investigate the usefulness of the video head impulse test (vHIT) as a method for evaluating vestibular function in patients with unilateral chronic middle ear disease.
Methods
Nineteen patients with various unilateral middle ear diseases including chronic otitis media (COM), COM with cholesteatoma, and adhesive otitis media successfully underwent preoperative vHIT. The gain of vestibuloocular reflex (VOR) and the presence of corrective saccades were compared between the affected ear and the healthy ear.
Results
A total of eight male and 11 female patients with a mean age of 43.1 years were included in this retrospective study. Twelve ears had COM, four had COM with cholesteatoma, and three had adhesive otitis media. A positive history of vertigo or dizziness was reported in 36.8% of the cases. The VOR gain of the affected ears and the healthy ears were 0.97±0.16 vs. 1.00±0.08 in the horizontal canal, 0.91±0.11 vs. 0.87±0.11 in the anterior canal, and 0.87±0.17 vs. 0.99±0.12 in the posterior canal, respectively. Only VOR gain of the posterior canal was significantly decreased compared with healthy ears.
Conclusions
The average VOR gains in the patients with chronic middle ear disease were within the pre-defined values of normality; however, when compared quantitatively, posterior canal gain of affected ears was significantly decreased compared to healthy ears. Our results can be explained by the anatomical proximity of the ampulla of the posterior canal and middle ear space.
Auto-Pattern Recognition for Diagnosis in Benign Paroxysmal Positional Vertigo Using Principal Component Analysis: A Preliminary Study
O-Hyeon Gwon, Tae Hoon Kong, Jaehong Key, Sejung Yang, Young Joon Seo
Res Vestib Sci. 2022;21(1):6-18.   Published online March 15, 2022
DOI: https://doi.org/10.21790/rvs.2022.21.1.6
  • 5,299 View
  • 85 Download
  • 1 Crossref
AbstractAbstract PDF
Objectives
The aim of this study was to develop a filtering algorithm for raw nystagmus images and a diagnostic assistive algorithm using a principal component analysis (PCA) to distinguish the different types of benign paroxysmal positional vertigo (BPPV).
Methods
Fifteen video clips of clinical data with typical nystagmus patterns of BPPV (13 cases) and with normal nystamgmus (two cases) were preprocessed when applied the thresholding, morphology operation, residual noise filtering, and center point extraction stages. We analyzed multiple data clusters in a single frame via a PCA; in addition, we statistically analyzed the horizontal and vertical components of the main vector among the multiple data clusters in the canalolithiasis of the lateral semicircular canal (LSCC) and the posterior semicircular canal (PSCC).
Results
We obtained a clear imaginary pupil and data on the fast phases and slow phases after preprocessing the images. For a normal patient, a round shape of clustered dots was observed. Patients with LSCC showed an elongated horizontal shape, whereas patients with PSCC showed an oval shape at the (x, y) coordinates. The scalar values (mm) of the horizontal component of the main vector when performing a PCA between the LSCC- and PSCC-BPPV were substantially different (102.08±20.11 vs. 32.36±12.52 mm, respectively; p=0.0012). Additionally, the salar ratio of horizontal to vertical components in LSCC and PSCC exhibited a significant difference (16.11±10.74 mm vs. 2.61±1.07 mm, respectively; p=0.0023).
Conclusions
The data of a white simulated imaginary pupil without any background noise can be a separate monitoring option, which can aid clinicians in determining the types of BPPV exhibited. Therefore, this analysis algorithm will provide assistive information for diagnosis of BPPV to clinicians.

Citations

Citations to this article as recorded by  
  • Development of An Algorithm for Slippage-Induced Motion Artifacts Reduction in Video-Nystagmography
    Yerin Lee, Young Joon Seo, Sejung Yang
    Research in Vestibular Science.2022; 21(4): 104.     CrossRef
Case Reports
Dissociated Vertical-Torsional Nystagmus in Vestibular Nucleus Lesion
Hyun-Sung Kim, Eun Hye Oh, Jae-Hwan Choi
Res Vestib Sci. 2022;21(1):19-23.   Published online March 15, 2022
DOI: https://doi.org/10.21790/rvs.2022.21.1.19
  • 3,187 View
  • 78 Download
AbstractAbstract PDF
Dissociated vertical-torsional nystagmus is a unique form of nystagmus characterized by conjugate torsional but disparate vertical components. It has been mainly reported in internuclear ophthalmoplegia or medial medullary lesion involving the medial longitudinal fasciculus (MLF). The patterns of the nystagmus may be explained by a disruption of vestibulo-ocular reflex pathways from vertical semicircular canal or utriculo-ocular reflex within the MLF, but it is debatable. We described a dissociated upbeat-torsional nystagmus in a patient with vestibular nucleus infarction without involvement of MLF.
Isolated Floccular Infarction with Impairment of High-Frequency Vestibulo-Ocular Reflex: A Case Report
Eun Hye Oh, Hyun-Sung Kim, Jae-Hwan Choi
Res Vestib Sci. 2021;20(4):147-150.   Published online December 15, 2021
DOI: https://doi.org/10.21790/rvs.2021.20.4.147
  • 2,613 View
  • 44 Download
AbstractAbstract PDF
The flocculus plays a crucial role in control of eye movements. Based on animal experiment, it is suggested that the flocculus is important for governing vestibuleocular reflexes. In humans, an isolated floccular lesion is extremely rare. We report oculomotor abnormalities in a patient with unilateral infarction of the flocculus, and compare our results with those of previously reported patients with floccular lesion.
Original Articles
Temporal Relationship between Nystagmus and Perception during Bithermal Alternate Caloric Test
Sooyoung Kim, Eun-Jin Kwon, Hyunjin Jo, Seong-Hae Jeong
Res Vestib Sci. 2021;20(4):134-140.   Published online December 15, 2021
DOI: https://doi.org/10.21790/rvs.2021.20.4.134
  • 2,829 View
  • 91 Download
AbstractAbstract PDF
Objectives
During caloric irritation, the spinning/rotating sensation is predominant. However, there is no report on the temporal relationship between caloric nystagmus and perception.
Methods
Consecutive 57 participants underwent bithermal caloric test in the dizziness clinic of Chungnam National University Hospital from February 2018 to September 2018. For vestibular perception, we asked the subject to report feelings of rotation and/or linear sensation during each warm and cold water irrigation period. Besides routine caloric parameters, the duration of nystagmus and vestibular sensation were analyzed.
Results
In most participants, the caloric nystagmus preceded the vestibular sensation (79.6% in right warm, 83.3% in left warm, 88.5% in right cool, and 84.6% in left cool stimuli). The precedence of perception was observed in 5 normal persons and 15 patients with vestibular migraine (n=4), unilateral vestibulopathy (n=3), and Menière’s disease (n=2), multiple systemic atrophy (n=2), cerebellar ataxia (n=2), vertebrobasilar insufficiency (n=1), and post-earthquake dizziness (n=1). The mean latency between nystagmus and perception was 11.7 seconds. And the duration of nystagmus was longer than that of perception in all conditions. Non-spinning sensations during the caloric test were also observed in some participants (26.8% in right warm, 30.3% in left warm, 29.1% in right cool, and 24.1% in left cool stimuli).
Conclusions
During the bithemal alternate caloric test, various vestibular perception and temporal relationship between perception and nystagmus suggest the bithermal caloric stimulation does not reflect only the signal originating from the horizontal canal pathway. A further validation study is needed.
Influence of Otoliths on the Vestibulo-Ocular Reflex in Horizontal Canal Benign Paroxysmal Positional Vertigo
Hee Soo Yoon, Jae Yeong Jeong, Jae Ho Chung, Ha Young Byun, Chul Won Park, Seung Hwan Lee
Res Vestib Sci. 2020;19(2):49-54.   Published online June 15, 2020
DOI: https://doi.org/10.21790/rvs.2020.19.2.49
  • 7,843 View
  • 131 Download
AbstractAbstract PDF
Objectives
The aim of the study was to evaluate the possible alteration of the vestibulo-ocular reflex (VOR) in patients with horizontal canal benign paroxysmal positional vertigo (h-BPPV) using the video head impulse test (vHIT).
Methods
This was a prospective case-control study of BPPV patients. We includeed 133 patients with h-BPPV who underwent the vHIT prior to the positioning test. The control group consisted of 76 normal subjects who also underwent the vHIT. The vHIT parameters of gain and asymmetry were assessed, and clinical parameters such as treatment duration, number of canalith reposition maneuvers executed and recurrence rates were evaluated. The VOR and clinical parameters were compared between the h-BPPV and control group. The VOR parameters of h-BPPV canalolithiasis were also compared with those of cupulolithiasis.
Results
The mean age of the patients was 56.5 years and the male to female ratio was 1:2.02. Of the patients, 75 were diagnosed as having the canalolithiasis type of h-BPPV, while the other 58 had the cupulolithiasis type. The mean vHIT gains of the ipsi-lesional horizontal canal plane were 1.13 and 1.15 in the h-BPPV and control group, respectively (p=0.564). However, the asymmetry of the VOR was significantly higher in the h-BPPV than the control group (p=0.013), while the gains and asymmetries of the vHIT in the canalolith and cupulolith types were not significantly different (p=0.454, p=0.826).
Conclusions
The asymmetry of VOR is significantly elevated in the cupulolith type of hBPPV.
Comparison of Suppression Head Impulse and Conventional Head Impulse Test Protocols
Kyung Jin Roh, Ju Young Kim, Eun Jin Son
Res Vestib Sci. 2019;18(4):91-97.   Published online December 15, 2019
DOI: https://doi.org/10.21790/rvs.2019.18.4.91
  • 6,243 View
  • 166 Download
  • 8 Crossref
AbstractAbstract PDF
Objectives
The head impulse test paradigm (HIMP) assesses semicircular canal function by measuring compensatory saccades during head movements as an indication of an impaired vestibulo-ocular reflex (VOR). The recently introduced suppression head impulse test paradigm (SHIMP) examines anticompensatory saccades after head movements as a measure of intact VOR. Thus, HIMP measures a decrease in vestibular function, whereas SHIMP measures residual function. We evaluated the effectiveness of SHIMP, compared HIMP and SHIMP results in the same subjects, and examined the relationship between the 2 tests.
Methods
HIMP and SHIMP protocols were performed in 73 patients. The patients were instructed to maintain their gaze on a fixed target for the HIMP, or a moving target for the SHIMP during head impulses. The VOR gain and saccade parameters were compared.
Results
HIMP and SHIMP data were obtained for all ears except in 3 patients. The VOR gain with SHIMP was smaller than for HIMP, but showed significant correlation (r=0.8356, p<0.001) and substantial agreement (k=0.79). However, neither the percentage of saccades (appearance of HIMP compensatory saccades and reduction of SHIMP anticompensatory saccades) nor their amplitudes were correlated between the 2 tests.
Conclusions
The HIMP and SHIMP protocols are valuable tools to evaluate VOR during high-velocity head movements. Our results confirm their agreement as measures of VOR gain during head impulses, but also show that the relationship between compensatory and anticompensatory saccades is not straightforward. Thus, care should be taken during clinical interpretation of either protocol.

Citations

Citations to this article as recorded by  
  • Normalization of the Suppression Head Impulse Test (SHIMP) and its correlation with the Head Impulse Test (HIMP) in healthy adults
    Suheda Baran, Gulce Kirazli, Pelin Pistav Akmese, Nese Celebisoy, Tayfun Kirazli
    Journal of Vestibular Research.2024; 34(1): 15.     CrossRef
  • Test-retest reliability of suppression head impulse paradigm (SHIMP) in healthy individuals
    Aishwarya Nagarajan, Shashish Ghimire, Varsha Sam Elizabeth, Sujeet Kumar Sinha
    Hearing, Balance and Communication.2023; 21(4): 312.     CrossRef
  • A nystagmus extraction system using artificial intelligence for video-nystagmography
    Yerin Lee, Sena Lee, Junghun Han, Young Joon Seo, Sejung Yang
    Scientific Reports.2023;[Epub]     CrossRef
  • Efeito da idade no equilíbrio corporal e nos resultados do vídeo teste do impulso cefálico em pacientes com insuficiência cardíaca
    Gizele Francisco Ferreira do Nascimento, José Diniz Júnior, Rosiane Viana Zuza Diniz, Miguel Angelo Hyppolito, Erika Barioni Mantello
    Audiology - Communication Research.2023;[Epub]     CrossRef
  • Effect of age on body balance and on the results of the video head impulse test in patients with heart failure
    Gizele Francisco Ferreira do Nascimento, José Diniz Júnior, Rosiane Viana Zuza Diniz, Miguel Angelo Hyppolito, Erika Barioni Mantello
    Audiology - Communication Research.2023;[Epub]     CrossRef
  • Development of An Algorithm for Slippage-Induced Motion Artifacts Reduction in Video-Nystagmography
    Yerin Lee, Young Joon Seo, Sejung Yang
    Research in Vestibular Science.2022; 21(4): 104.     CrossRef
  • VOR gain of lateral semicircular canal using video head impulse test in acute unilateral vestibular hypofunction: A systematic review
    Mohamad Alfarghal, Mohammed Abdullah Algarni, Sujeet Kumar Sinha, Aishwarya Nagarajan
    Frontiers in Neurology.2022;[Epub]     CrossRef
  • Evaluation of high frequency horizontal VOR parameters in patients with chronic bilateral and unilateral peripheral vestibulopathy: a preliminary study
    Gulce Kirazli, Sevinc Hepkarsi, Tayfun Kirazli
    Acta Oto-Laryngologica.2020; 140(12): 1007.     CrossRef
Analysis of Age-Dependent Normative Values of Suppression Video-Head-Impulse Test in Healthy Korean Subjects
Do Yoon Jeong, Yoon Sik Park, Sung Il Cho
Res Vestib Sci. 2019;18(1):8-13.   Published online March 15, 2019
DOI: https://doi.org/10.21790/rvs.2019.18.1.8
  • 5,425 View
  • 90 Download
  • 1 Crossref
AbstractAbstract PDF
Objectives
Suppression head impulse paradigm (SHIMP) in video head impulse test is now newly used to test vestibular function. The aim of this study was to analyze normative values of SHIMP for healthy Korean subjects in each decade of life.
Methods
SHIMP and HIMP responses were measured with the video head impulse test in 70 healthy subjects. Vestibulo-ocular reflex gain and anticompensatory saccade were analyzed and compared at each decade of life.
Results
All subjects produced anticompensatory saccades in SHIMP. Gain values did not vary significantly with age. Gain values in SHIMP were lower than gain values in HIMP. The gain values of rightward impulse were higher than the gain values of leftward impulse.
Conclusions
Gain values and anticompensatory saccades in SHIMP were consistently equal in each decade of life. Normative values of SHIMP seems largely unaffected by aging.

Citations

Citations to this article as recorded by  
  • Normalization of the Suppression Head Impulse Test (SHIMP) and its correlation with the Head Impulse Test (HIMP) in healthy adults
    Suheda Baran, Gulce Kirazli, Pelin Pistav Akmese, Nese Celebisoy, Tayfun Kirazli
    Journal of Vestibular Research.2024; : 1.     CrossRef
Review
Clinical Application and Update of Video Head Impulse Test
Jung Yup Lee, Jin Su Park, Min-Beom Kim
Res Vestib Sci. 2018;17(3):79-89.   Published online September 18, 2018
DOI: https://doi.org/10.21790/rvs.2018.17.3.79
  • 11,932 View
  • 1,329 Download
  • 8 Crossref
AbstractAbstract PDF
Recently with the introduction of video head impulse test (vHIT), it can be easily performed quantitative and objective measurement of vestibulo-ocular reflex (VOR). vHIT has been used as a clinical vestibular function test that can individually evaluate the function of each semicircular canal. Loss of VOR gain and corrective catch-up saccades that occur during the vHIT usually indicate peripheral vestibular hypofunction, whereas in acute vestibular syndrome, normal vHIT should prompt a search for a central lesion. In this study, we will examine the principle of vHIT and its interpretation, and explain its clinical application in peripheral and central vestibulopathy. In addition, we will compare the caloric test and the differences, and review the most recently introduced suppression head impulse paradigm test.

Citations

Citations to this article as recorded by  
  • Application of the Barany Society's Presbyvestibulopathy Criteria in Older Adults With Chronic Dizziness
    Joon‐Pyo Hong, Min‐Beom Kim
    Otolaryngology–Head and Neck Surgery.2024; 170(2): 515.     CrossRef
  • Vestibular mapping in Ramsay-Hunt syndrome and idiopathic sudden sensorineural hearing loss
    Joon-Pyo Hong, Jung-Yup Lee, Min-Beom Kim
    European Archives of Oto-Rhino-Laryngology.2023; 280(12): 5251.     CrossRef
  • Re-fixation Saccade at Video-Head Impulse Test in Patients with Sudden Sensorineural Hearing Loss
    Dong Hyuk Jang, Sun Seong Kang, Hyun Joon Shim, Yong-Hwi An
    Research in Vestibular Science.2023; 22(2): 46.     CrossRef
  • A Comparative Analysis of the Vestibulocochlear Function in Patients with Isolated Semicircular Canal Hypofunction Using a Video Head Impulse Test
    Yu Jung Park, Min Young Lee, Ji Eun Choi, Jae Yun Jung, Jung Hwa Bahng
    Research in Vestibular Science.2023; 22(2): 34.     CrossRef
  • A Comparative Study Using Vestibular Mapping in Sudden Sensorineural Hearing Loss With and Without Vertigo
    Joon‐Pyo Hong, Jung‐Yup Lee, Min‐Beom Kim
    Otolaryngology–Head and Neck Surgery.2023; 169(6): 1573.     CrossRef
  • A Study on the Evaluation of Brainstem Dysfunction in Rapid Eye Movement Sleep Behavior Disorder Using Video Nystagmography
    Young Hun Kim, Jeongho Park, Seung Ho Choo, Hyunjin Jo, Dae-Won Seo, Byung-Euk Joo, Eun Yeon Joo
    Journal of the Korean Neurological Association.2023; 41(4): 293.     CrossRef
  • Vestibular mapping assessment in idiopathic sudden sensorineural hearing loss
    Hee Won Seo, Jae Ho Chung, Hayoung Byun, Seung Hwan Lee
    Ear & Hearing.2022; 43(1): 242.     CrossRef
  • Group Vestibular Rehabilitation Program: A Cost-Effective Outpatient Management Option for Dizzy Patients
    Jae Sang Han, Jung Mee Park, Yeonji Kim, Jae-Hyun Seo, So Young Park, Shi Nae Park
    Otology & Neurotology.2022; 43(9): 1065.     CrossRef
Original Article
Clinical Significance of Perverted Head-Shaking Nystagmus
Tae-Ho Yang, Byung-Soo Shin, Man-Wook Seo, Sun-Young Oh
Res Vestib Sci. 2017;16(4):119-128.   Published online December 15, 2017
DOI: https://doi.org/10.21790/rvs.2017.16.4.119
  • 10,548 View
  • 236 Download
AbstractAbstract PDF
Objectives
We investigated clinical significance of head shaking nystagmus (HSN) and perverted HSN (pHSN) in patients with peripheral and central vestibular disorders. Methods: We reviewed medical records of 822 consecutive subjects who were referred to a dizziness clinic. We performed neurologic examination including video-oculography in darkness for 60 seconds before, during and for 100 seconds after head-shaking. HSN was considered to develop when post-head-shaking nystagmus last at least 5 beats with latency from end of head-shaking of no more than 5 seconds, and a velocity at least 3°/sec. Results: In control group (n=45), there were observed spontaneous nystagmus (SN) in 2.2%, HSN in 17.8%, pHSN in 6.7%. In patients with peripheral vestibular disorder group (n=397), there were observed SN in 14.1%, HSN in 40.6%, pHSN in 9.8%. In patients with central vestibular disorder group (n=217), there were observed SN in 17.5%, HSN in 24.0%, pHSN in 13.4%. In unspecified dizziness group (n=208), there were observed SN in 1.9%, HSN in 13.0%, pHSN in 1.9%. pHSN was frequently observed in central vestibular disorders such as stroke, vestibular migraine, cerebellar ataxia, and vertebro-basilar insufficiency. However, pHSN was also observed at higher rate than expected in peripheral vestibular disorders including benign paroxysmal positional vertigo especially involving vertical canals, Meniere disease and even in unilateral vestibulopathy. Conclusions: Our results show that perverted HSN in dizzy populations was frequently observed not only in cases of central vestibular disorders but also in peripheral disorders. Perverted HSN can develop by any conditions that cause difference in vestibular velocity storage in vertical component of vestibular-ocular reflex.
Case Report
Four Cases of Wernicke’s Encephalopathy with Impaired Horizontal Vestibular Ocular Reflexes
Hyuk-Su Jang, Byoung-Soo Shin, Man-Wook Seo, Sun-Young Oh
Res Vestib Sci. 2017;16(2):57-63.   Published online June 15, 2017
DOI: https://doi.org/10.21790/rvs.2017.16.2.57
  • 8,483 View
  • 221 Download
AbstractAbstract PDF
Wernicke’s encephalopathy (WE) is a neurological disorder induced by a dietary vitamin B1 (thiamine) deficiency which is characterized by encephalopathy, gait ataxia, and variant ocular motor dysfunction. In addition to these classical signs of WE, a loss of the horizontal vestibulo-ocular reflex (VOR) is being reported as the major underdiagnosed symptoms in WE. In this retrospective single center study, we report four cases of WE initially presented with impaired horizontal VOR in addition to the classical clinical presentations, and imaging and neurotological laboratory findings were described.
Original Articles
Vestibulo-Ocular Reflex Recordings of Small Rodents using a Novel Marker Array
Mi Joo Kim, Jiyeon Lee, Eui Jae Hong, Eun Ji Lee, Yu Jin Min, Dong Ju Lee, Nam Beom Kim, Gyu Cheol Han
Res Vestib Sci. 2016;15(1):11-16.
  • 2,480 View
  • 67 Download
AbstractAbstract PDF
Objective: Recording the nystagmus of small experimental rodents is an integral technique in vestibular research. Theoretically, the size and the shape of markers strongly affect the analysis of 3 dimensional nystagmus.
Methods
The nystagmus of 6 healthy ICR mice were recorded and their gain values were compared using 200 μm, 300 μm, 400 μm, and 600 μm isosceles triangle markers at the peak velocity of 60o/sec and 100o/sec with the rotational stimulations of 0.1 Hz, 0.2 Hz, and 0.5 Hz.
Results
The gain values of 3 different sizes of the markers showed no significant differences in horizontal- vertical-torsional component. However, it was unable to record the nystagmus with 200 μm markers since the markers were too small to be placed and stayed on the center of the pupils.
Conclusion
Technicians can decide the size of the markers from 200 to 600 ?m to record the nystagmus of mice, depending on the technicians’ skills.
Assessment of Vestibular Functional Recovery Using Video Head Impulse Test in Vestibular Neuritis
Jun Hyun Kim, Tae Kyeong Lee, Sang Woo Lee, Nari Choi, Seungcheol Lee, Ki Bum Sung
Res Vestib Sci. 2015;14(4):132-138.
  • 2,632 View
  • 107 Download
AbstractAbstract PDF
Objective: The video head impulse test (vHIT) is useful for evaluation of high frequency vestibulo-ocular reflex. There are a few reports regarding the recovery of head impulse test in vestibular neuritis (VN) but the factors for the recovery were not studied. The study aimed to identify the recovery patterns of vHIT in VN and the factors influencing the recovery.
Methods
Among 31 patients with acute VN, 18 patients with identified recovery pattern were selected. We conducted serial checks of subjective vertigo and spontaneous nystagmus until discharged (1?8 days), and scheduled vHITs. We found three patterns in serial vHITs during follow-ups and analyzed the relationship of initial vestibular function tests, serial check-ups of subjective vertigo, bedside neuro-otologic tests, and vHITs.
Results
Five patients showed normal vHIT gain in acute stage (non-damaged pattern) and 8 patients’ gains were recovered after 30 days after symptom onset (early recovered pattern). Poor recovery pattern was found in 5 patients (poorly recovered pattern). There were relationship between vHIT recovery patterns and the severity of vestibular dysfunctions. Duration of spontaneous nystagmus (until grade 1), degree of subjective visual vertical tilt, ocular vestibular myogenic potential abnormalities, and abnormality of rotatory chair test were all related to poorly recovered vHIT patterns. All poor recovery patients had residual symptom at 30 days after symptom onset.
Conclusion
The vHIT may give clinicians useful hints in predicting prognosis in VN, and the recovery of vHIT would be delayed if the damage were more extensive.
Vestibular Dysfunctions in Vestibular Migraine Evaluated by Rotatory Chair Test
Ji Yun Park, Byeong Cheo Oh, Tae Kyeong Lee, Ki Bum Sung
Res Vestib Sci. 2015;14(4):123-131.
  • 2,513 View
  • 138 Download
AbstractAbstract PDF
Objective: There have been several efforts to elucidate the pathophysiology of the vestibular migraine (VM). But, there is no consistent result. This study was to identify the possible pathophysiology of VM by comparing vestibulo-ocular reflex (VOR) parameters between VM, and the tension type headache (TTH) patients. In addition, we compared VOR parameters between ictal and interictal period in the VM group.
Methods
Seventy eight patients were included: 44 having VM and 34 TTH. Three parameters (gain, asymmetry, and phase) of the horizontal VOR rotating at 60 degrees were measured. In 10 VM patients VOR parameters were obtained twice sequentially first in the ictal and second in the interictal period.
Results
Although the average of the VOR gain in VM group was lower than that of TTH group but there was no statistical significance. An asymmetry of the VOR was significantly higher in VM group. There were various changes in other VOR parameters between ictal and interictal periods with no consistent trends.
Conclusion
We could deduce that VM patients might have subclinical vestibular dysfunction from the reduced gain and increased asymmetry of the VOR in the interictal period. Dynamic changes of the VOR in the ictal period could be responsible for dizziness in VM patients, which are caused by the pathological alteration of the physiologic plasticity of the VOR.

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