• Annals of Clinical Neurophysiology
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• 제7권1호
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• pp.1-6
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• 2005

Loud click or tone burst sound can activate vestibular receptor and evoke reflex changes in tonic electromyographic activity within the stenocleidomastoid muscles. This reflex is assumed to originate in the saccule, the afferent pathways being the inferior vestibular nerve, and the efferent pathways the vestibulospinal tract. Averaging these muscular responses allows vestibular evoked myogenic potentials (VEMP) to be obtained. The earliest response ipsilateral to a loud click, p13n23, is dependent upon vestibular activation, specifically saccular afferents. These new techniques are beginning to be applied clinically in the patient of vestibular neuritis, Meniere's disease, acoustic neuromas, Tullio phenomenon, etc. VEMP recording will provide both a straightforward non-invasive exploration of each vestibule independently and an attractive method by which to explore otolithic receptors and vestibulospinal pathways.

• Annals of Clinical Neurophysiology
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• 제8권1호
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• pp.53-57
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• 2006

Background: Vstibular evoked myogenic potentials(VEMP) have been known to be useful documenting abnormality in patients with various vestibular disorders and brainstem lesions but the studies of VEMP in patients with hemispheric lesions are rare. Methods: We recorded VEMP in 21 consecutive patients with acute ischemic stroke in the supratentorial lesions without evidence of brainstem or vestibular end organ lesions. All patients underwent magnetic resonance imaging and the main outcome measures of VEMP were recorded in all subjects. We interpreted each parameters of VEMP using our normal laboratory data. Results: VEMP abnormalities(prolonged latency or asymmetry of amplitude) were found in 57%(12/21) of acute infarction patients with supratentorial lesions. Bilateral VEMP abnormalities were found in six patients and unilateral abnormalities were found in another six patients with ipsilateral abnormalities in the three and controlateral abnormalities in the three patients. Conclusions: VEMP abnormalities were found in supratentorial stroke patients in our studies and this findings suggest supranuclear control may affect the generation of VEMP potentials.

• Annals of Clinical Neurophysiology
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• 제7권2호
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• pp.80-82
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• 2005

Background: Idiopathic Parkinson's disease (IPD) is closely related to Lewy body pathology. Pathological changes in medullar oblongata and pontine tegmentum have been reported in patients with subclinical motor symptom. Vestibular evoked myogenic potential (VEMP) is mediated by vestibular nuclei in lower brainstem and reflects the function of lower brainstem. The purpose of our study is to estimate the lower brainstem function in IPD patients. Methods: Ten patients with idiopathic Parkinson's disease underwent VEMP test. The patients were divided into Hohn-Yahr (H-Y) stage I (unilateral motor involvement) group and H-Y stage II or more severe (bilateral motor involvement) group. VEMP results were compared between groups using Mann-Whitney U test. Results: Among patients, 6 patients showed abnormal VEMP (unilateral abnormality 2, bilateral abnormalities 4). Between H-Y stage I group and H-Y II,III group, there was no statistical difference in the results of VEMP. Conclusions: We concluded that the lower brainstem dysfunction reflected in VEMP could occur in IPD regardless of the progression of the disease.

• Journal of Audiology & Otology
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• 제23권1호
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• pp.49-52
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• 2019

Background and Objectives: Considering important role of vitamin D in many physiological processes including vestibular system in the ear, aim of present study is to evaluate saccule function via cervical vestibular evoked myogenic potential (cVEMP), in patients with vitamin D deficiency. Subjects and Methods: After routine audiological tests, cVEMP were recorded in 15 patients with vitamin D deficiency and 16 normal subjects. The short tone burst (95 dB nHL, 500 Hz) was presented to ears. cVEMP was recorded with surface electromyography over the contracted ipsilateral sternocleidomastoid muscle. Results: Mean of p13, n13, interpeak latencies and amplitude ratios were measured in both groups. Statistical analysis did not show differences between two groups. Conclusions: Maybe serum 25-hydroxyvitamin D concentration was not low enough to have effect on saccule in the patients in present study or saccule have had low susceptibility to effects of vitamin D deficiency. For better judgment about effect of vitamin D deficiency on saccular function planning studies with high sample size is recommended.

• 대한청각학회지
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• 제23권1호
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• pp.49-52
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• 2019

Background and Objectives: Considering important role of vitamin D in many physiological processes including vestibular system in the ear, aim of present study is to evaluate saccule function via cervical vestibular evoked myogenic potential (cVEMP), in patients with vitamin D deficiency. Subjects and Methods: After routine audiological tests, cVEMP were recorded in 15 patients with vitamin D deficiency and 16 normal subjects. The short tone burst (95 dB nHL, 500 Hz) was presented to ears. cVEMP was recorded with surface electromyography over the contracted ipsilateral sternocleidomastoid muscle. Results: Mean of p13, n13, interpeak latencies and amplitude ratios were measured in both groups. Statistical analysis did not show differences between two groups. Conclusions: Maybe serum 25-hydroxyvitamin D concentration was not low enough to have effect on saccule in the patients in present study or saccule have had low susceptibility to effects of vitamin D deficiency. For better judgment about effect of vitamin D deficiency on saccular function planning studies with high sample size is recommended.

• Journal of Yeungnam Medical Science
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• 제39권2호
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• pp.81-88
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• 2022

Vertigo is the sensation of self-motion of the head or body when no self-motion is occurring or the sensation of distorted self-motion during an otherwise normal head movement. Representative peripheral vertigo disorders include benign paroxysmal positional vertigo, Ménière disease, and vestibular neuritis. Vestibular neuritis, also known as vestibular neuronitis, is the third most common peripheral vestibular disorder after benign paroxysmal positional vertigo and Ménière disease. The cause of vestibular neuritis remains unclear. However, a viral infection of the vestibular nerve or ischemia of the anterior vestibular artery is known to cause vestibular neuritis. In addition, recent studies on immune-mediated mechanisms as the cause of vestibular neuritis have been reported. The characteristic clinical features of vestibular neuritis are abrupt true-whirling vertigo lasting for more than 24 hours, and no presence of cochlear symptoms and other neurological symptoms and signs. To accurately diagnose vestibular neuritis, various diagnostic tests such as the head impulse test, bithermal caloric test, and vestibular-evoked myogenic potential test are conducted. Various treatments for vestibular neuritis have been reported, which are largely divided into symptomatic therapy, specific drug therapy, and vestibular rehabilitation therapy. Symptomatic therapies include generalized supportive care and administration of vestibular suppressants and antiemetics. Specific drug therapies include steroid therapy, antiviral therapy, and vasodilator therapy. Vestibular rehabilitation therapies include generalized vestibular and customized vestibular exercises.

• Journal of Audiology & Otology
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• 제23권2호
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• pp.103-111
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• 2019

Background and Objectives: Dizzy patients with abnormal otolith function tests, despite a normal caloric response, are defined as having specific (isolated) otolith organ dysfunction. This study was performed to compare the differences in clinical presentation between isolated otolith dysfunction (iOD) patients with lab- and Sx-based iOD group and lab-based iOD symptoms. Subjects and Methods: The medical records of 23 iOD patients with normal caloric response but abnormal cervical vestibular evoked myogenic potential (VEMP), ocular VEMP, or subjective visual vertical were reviewed. Non-spinning vertigo was considered as otolith-related symptoms. The patients' age, onset of dizziness, Numeric Rating Scale on the severity of dizziness, and concomitant vestibular disorders were analyzed. Results: Patients in the lab-based iOD group were significantly older than those in the lab- and Sx-based iOD group. Known vestibular disorders were significantly more common in the lab-based iOD group (83.3%) compared to the lab- and Sx-based iOD group (18.2%). Despite the normal caloric response, catch-up saccade was found in the video head impulse test in more than half (54.5%) of the lab-based iOD group patients. There was no catch-up saccade in the lab- and Sx-based iOD group. There were no significant differences in gender ratio, frequency of dizziness attacks, and duration of illness. Conclusions: We propose new definitions of definite iOD (lab- and Sx-based iOD) and probable iOD (lab- or Sx-based iOD). These new definitions may help researchers to identify patients who are more likely to have true iOD, and facilitate comparisons of results between different studies.

• 대한청각학회지
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• 제23권2호
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• pp.103-111
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• 2019

Background and Objectives: Dizzy patients with abnormal otolith function tests, despite a normal caloric response, are defined as having specific (isolated) otolith organ dysfunction. This study was performed to compare the differences in clinical presentation between isolated otolith dysfunction (iOD) patients with lab- and Sx-based iOD group and lab-based iOD symptoms. Subjects and Methods: The medical records of 23 iOD patients with normal caloric response but abnormal cervical vestibular evoked myogenic potential (VEMP), ocular VEMP, or subjective visual vertical were reviewed. Non-spinning vertigo was considered as otolith-related symptoms. The patients' age, onset of dizziness, Numeric Rating Scale on the severity of dizziness, and concomitant vestibular disorders were analyzed. Results: Patients in the lab-based iOD group were significantly older than those in the lab- and Sx-based iOD group. Known vestibular disorders were significantly more common in the lab-based iOD group (83.3%) compared to the lab- and Sx-based iOD group (18.2%). Despite the normal caloric response, catch-up saccade was found in the video head impulse test in more than half (54.5%) of the lab-based iOD group patients. There was no catch-up saccade in the lab- and Sx-based iOD group. There were no significant differences in gender ratio, frequency of dizziness attacks, and duration of illness. Conclusions: We propose new definitions of definite iOD (lab- and Sx-based iOD) and probable iOD (lab- or Sx-based iOD). These new definitions may help researchers to identify patients who are more likely to have true iOD, and facilitate comparisons of results between different studies.