• Title/Summary/Keyword: Brainstem

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Glutamate-Induced Serotonin Depletion in Fetal Rat Brainstem Cultures (흰쥐태 뇌간의 배양에서 Glutamate에 의한 Serotonin의 고갈)

  • Park, Sang-Wook;Wie, Myung-Bok;Song, Dong-Keun;Kim, Yong-Sik;Kim, Yung-Hi
    • The Korean Journal of Pharmacology
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    • v.29 no.2
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    • pp.189-193
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    • 1993
  • Exposure of dissociated cultures from fetal rat brainstem to glutamate for upto 6 h decreased cellular contents of 5-hydroxytryptamine and 5-hydroxyindoleacetic acid in a concentration- and time-dependent manner. In addition, glutamate induced lactate dehydrogenase leakage. Tetrodotoxin did not block the effects induced by glutamate. MK-801 $(1{\mu}M)$, an N-methyl-D-aspartate (NMDA) channel blocker, but not 6-cyano-2,3-dihydroxy-7-nitro-quinoxazoline $(CNQX;\;3{\mu}M)$, a non-NMDA receptor antagonist, blocked glutamate-induced effects, indicating that these glutamate-induced responses are mediated through NMDA receptors.

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Bickerstaff's Brainstem Encephalitis Treated with Immunoglobulin (면역글로불린으로 치료한 Bickerstaff 뇌간뇌염 1예)

  • Kim, Beom Joon;Choi, Yoon Jae;Kim, Nam-Hee;Hong, Yoon-Ho;Sung, Jung-Joon;Han, Moon-Ku;Park, Seong-Ho;Lee, Kwang-Woo;Park, Kyung Seok
    • Annals of Clinical Neurophysiology
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    • v.8 no.1
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    • pp.94-97
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    • 2006
  • Bickerstaff's brainstem encephalitis (BBE) is a rare disorder with acute ophthalmoparesis, ataxia, consciousness disturbance, and pyramidal signs of suspected autoimmune origin. A-62-year-old woman developed acute diplopia, dysarthria, gaze-paretic nystagmus and gait ataxia. Her mental status fell subsequently into stupor. Brain MRI and nerve conduction study showed no significantly abnormal findings. Electroencephalography revealed diffuse low voltage slowings. After treating with intravenous immunoglobulin, she demonstrated rapid clinical recovery. This case suggests that immunoglobulin can be an alternative option in BBE treatment, especially when plasmapheresis and corticosteroids are difficult or contraindicated.

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Basic Techniques of Intraoperative Neurophysiological Monitoring

  • Park, Sang-Ku;Hyun, Soon-Chul;Lim, Sung-Hyuk;Park, Chan-Woo;Park, Jin-Woo;Kim, Dong-Jun;Choi, Wan-Soo;Kim, Gi-Bong
    • Korean Journal of Clinical Laboratory Science
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    • v.45 no.2
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    • pp.77-85
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    • 2013
  • Intraoperative Neurophysiological Monitoring (INM) is very useful in monitoring the motorsensory pathway and vascular circulation system during intraspinal, or intracranial neurosurgery. Brainstem Auditory Evoked Potentials (BAEPs) are for detecting the problems along the auditory pathways including, the eighth cranial nerve and brainstem. Motor Evoked Potentials (MEPs) is a useful adjunct to conventional monitoring of Somato-sensory Evoked Potentials (SEPs) during surgery. Visual Evoked Potentials (VEPs) has been regarded as having limited significance for the preservation of visual function during neurosurgical procedures. In this paper, we propose that the most appropriate averaging of the number of inspections in the inspection of each used in the operative field, is good and efficient, functionally.

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Development of Cone-Shaped Electrode for Promontory Stimulation Electrically Auditory Brainstem Response (와우 갑각 전기자극 뇌간유발반응용 원추형 전극의 개발)

  • Heo, Seung-Deok;Jung, Dong-Keun;Kang, Myung-Koo;Kim, Lee-Suk;Ko, Do-Heung
    • Speech Sciences
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    • v.10 no.4
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    • pp.181-187
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    • 2003
  • This paper introduces a new zinc coated copper wire electrode with coiled cone shape which has low surface resistance and tolerance to the motion artifact for promontory stimulation electrically auditory brainstem responses (PSEABR). Auditory brainstem responses (ABR) can be used to predict hearing threshold level with a great deal of accuracy particularly for a young child who cannot cooperate mechanically and some hearing impaired who are exaggerating a hearing loss for economic compensation. While severe profound sensorineural hearing losses may not be implemented by auditory potentials, PSEABR is proven as a useful tool even for some sensorineural related hearing impaired. It was shown that PSEABR gives the electrical stimuli to promontory of the cochlear instead of giving acoustic stimuli. For this reason, PSEABR can be used as an alternative for cochlear implantation, and can also be used as an optimal device selection and neural information for MAP. It was found that the role of electrode is very important in PSEABR. Even though this cone-shaped electrode was applied in animal experiments, waveforms are well produced by PSEABR. Thus, it was concluded that cone-shaped electrode turned out to be a useful preoperative audiological evaluation tool in deciding time for cochlear implantation surgery.

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Vestibular Evoked Myogenic Potentials in Infratentorial Infarction Patients (천막아래 뇌경색 환자에서 전정유발근육전위)

  • Kim, Kwang-Ki;Lee, Seung Hwan;Won, Jun Yeon;Seol, Ho Jun;Kim, Sung Hun
    • Annals of Clinical Neurophysiology
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    • v.7 no.2
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    • pp.75-79
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    • 2005
  • Vestibular evoked myogenic potentials (VEMP) have been known to useful in documenting abnormality in patients with various vestibular disorders but the studies of VEMP in stroke patients are rare. We recorded VEMP in 17 consecutive patients with acute ischemic stroke in the brainstem lesions. All patients underwent magnetic resonance imaging and we compare VEMP results with the lesion documented by brain imaging. VEMP were defined to be abnormal when they were very asymmetrical (one is 2 times of more as large as the other), or absent in one side. VEMP abnormalities were found in 71%(12/17) of acute infarction patients with brainstem lesions. Most abnormalities found in the ipsilateral side of the lesion(9/12) but abnormalities in contralateral side of lesion were found in 25%(3/12) of patients.VEMP would be considered a useful complementary neurophysiological tool for the evaluation of brainstem dysfunction in acute stroke patients.

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Bilateral Congenital Deafness in a White Bull Terrier; Brainstem Auditory Evoked Response Findings

  • Kang, Byeong-Teck;Lee, So-Young;Jung, Dong-In;Kim, Hyung-Joong;Woo, Eung-Je;Park, Hee-Myung
    • Journal of Veterinary Clinics
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    • v.25 no.6
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    • pp.506-509
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    • 2008
  • A 2-month-old, intact female white Bull Terrier presented because of suspected deafness. The coat color was predominantly white and the iris color, of both eyes, was brown. The dog did not respond to the owner's voice when the sound stimuli were presented outside of the visual field; however, the dog responded to visual gestures. The other physical, neurological, otoscopic, radiographic, and blood examinations were unremarkable. To assess the apparent deafness, brainstem auditory evoked responses (BAER) were recorded and analyzed in the dog with suspected deafness as well as a normal littermate. The response in the normal littermate consisted of a series of five wave peaks (I-V) with decreased amplitude and prolonged latency as the stimulus intensity decreased. The BAER from the dog suspected of deafness appeared as a flat line and did not reveal identifiable peaks that corresponded to those found in the normal littermate. Thus, congenital, sensorineural and bilateral deafness was confirmed by the BAER.

A Comparative Study on Brainstem Auditory-Evoked Response between Dogs and Cats

  • Myeong-Yeon Lee;Sorin Choi;Dong-In Jung
    • Journal of Veterinary Clinics
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    • v.40 no.6
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    • pp.414-422
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    • 2023
  • Hearing assessment is critical in dogs and cats. Hearing loss in dogs and cats may be congenital or secondary to a central nervous system disorder or ear disease. The brainstem auditory-evoked response (BAER) test has been developed as an electrophysiological test for auditory function assessment. Modern BAER equipment is based on a computerized system. Thus, auditory function assessment can be performed using this objective, safe, and noninvasive method. No study has yet investigated the interspecies differences between BAER test results of dogs and cats. Therefore, the present study aimed to analyze the differences in BAER test results between dogs and cats. The test was conducted on four healthy adult dogs and four healthy adult cats. Regarding latency, lower values were obtained for all waveforms above 50 dB in cats compared to dogs. Regarding amplitude, cats showed higher values than dogs at intensities above 50 dB. Through a comparative analysis in this study, it was concluded that the two species had statistically significant differences. The BAER data of dogs cannot be applied to cats, and vice versa.

Medulla Oblangata Injury Caused by Non-Penetrating Trauma by Chopsticks (젓가락에 의한 비관통성 외상에 의해 유발된 연수 손상 1예)

  • Jin, Hyeon-Ju;Yu, Jae-Seong;Kim, Yu-Kyung;Gang, Ho-Seok;Lee, Se-Jin
    • Journal of Yeungnam Medical Science
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    • v.27 no.2
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    • pp.122-126
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    • 2010
  • It is common m childhood that children suffer intracavity or head injury, falling down backward, having chopsticks in their mouth. But most of them have paralysis of upper and lower extremity because of secondary damage by penetrating injury of brainstem and spine. We could not find this case which have shown infaction of medulla oblangata on MRI and paralysis by impact only without clear penetrating evidence. So the authors report this case with study of literature because we experience one case that have high signal density in brainstem on MRI, Loss of consciousness, and left hemiplegia without clear penetrating evidence after falling down backward, having chopsticks in her mouth and regard it rare case.

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Positive Peaked Electrically Compound Action Potentials in Cochlear Implant Recipients (인공와우 이식자에서 Positive Peaked 청신경 복합활동전위)

  • Heo, Seung-Deok
    • Phonetics and Speech Sciences
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    • v.1 no.2
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    • pp.25-30
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    • 2009
  • Animal experiments have shown that the positive peaked electrically compound action potentials (ECAPs) can be recorded in round window, intracochlear, and nerve trunk by stimulating a monopolar pulse. However, positive peaked ECAPs of cochlear implant recipients have never been reported because ECAPs are recorded from intracochlear electrodes after bipolar stimulation. In our experiment, the positive peaked ECAPs were recorded from 18 intracochlear electrodes in cochlear implant recipients with multiple cochlear anomalies. Thresholds in each channel were measured and the latency of P-, N-wave, and amplitude of P-N were analyzed. These results were identical with the electrically auditory brainstem response (EABR) on the input-output characteristics. In conclusion, the positive peaked ECAPs from the cochlear implant recipients are antidromic ECAPs recorded by perimodiolar electrodes stimulating cochlear implants with multiple anomalies. Therefore, positive peaked ECAPs can be used as useful audiological tools to evaluate the eighth nerve ending.

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