• The Korean Journal of Physiology and Pharmacology
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• v.7 no.4
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• pp.193-198
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• 2003

In the present study, the vestibularly evoked activity of inferior olive (IO) neurons was examined to investigate the vertical vestibular information transmitted through the vestibulo-olivo-cerebellar climbing fiber pathway. The extracellular recording was made in 74 neurons of the IO of cats, while animals were sinusoidally rotated. Most of vestibularly activated IO neurons responded to the vertical rotation (roll) test and were found in or near the ${\beta}$ subnuclei $(IO{\beta})$. The vestibular IO neurons were activated, when the animal was rotated to the side contralateral to the recording site. In contrast to the observation that the gain of responses of yaw sensitive cells (YSC) was not changed by the rotation frequency, that of the roll-sensitive cells (RSC) decreased as the rotation frequency was increased. Regardless of RSC or HSC, IO neurons showed the tendency of phase-lag in their responses. The alternating excitatory and inhibitory phases of responses of RSC were dependent on the direction of head orientation, the characteristics of which are the null response plane (NRP) and the optimal response plane (ORP). The analysis based on the NRP of RSC showed that vestibular inputs from the ipsilateral anterior semicircular canal induced the NRP of the RSC response at about 45 degree counterclockwise to the longitudinal axis of the animal, and that those inputs were distributed to RSC in the rostral part of $IO{\beta}$. On the other hand, those from the posterior semicircular canal were related with the NRP at about 45 degree clockwise and with the caudal part of the $IO{\beta}$. These results suggest that IO neurons receive and encode the vestibular information, the priority of which seems to be the vertical component of the body movement rather than the horizontal ones.

• Imaging Science in Dentistry
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• v.43 no.3
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• pp.135-143
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• 2013

Purpose: This study was performed to obtain a quantitative evaluation of the cortical and cancellous bone graft harvestable from the mental and canine regions, and to evaluate the cortical vestibular thickness. Materials and Methods: This study collected cone-beam computed tomographic (CBCT) images of 100 Italian patients. The limits of the mental region were established: 5 mm in front of the medial margin of each mental foramen, 5 mm under the apex of each tooth present, and above the inferior mandibular cortex. Cortical and cancellous bone volumes were evaluated using SimPlant software (SimPlant 3-D Pro, Materialize, Leuven, Belgium) tools. In addition, the cortical vestibular thickness (minimal and maximal values) was evaluated in 3 cross-sections corresponding to the right canine tooth (3R), the median section (M), and the left canine tooth (3L). Results: The cortical volume was $0.71{\pm}0.23mL$ (0.27-1.96 mL) and the cancellous volume was $2.16{\pm}0.76mL$ (0.86-6.28 mL). The minimal cortical vestibular thickness was $1.54{\pm}0.41mm$ (0.61-3.25 mm), and the maximal cortical vestibular thickness was $3.14{\pm}0.75mm$ (1.01-5.83 mm). Conclusion: The use of the imaging software allowed a patient-specific assessment of mental and canine region bone availability. The proposed evaluation method might help the surgeon in the selection of the donor site by the comparison between bone availability in the donor site and the reconstructive exigency of the recipient site.

• The Journal of Korean Academy of Sensory Integration
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• v.9 no.2
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• pp.29-39
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• 2011

Objective : The purpose of this study is to verify the effect of sensory integrative intervention focused on proprioceptive-vestibular stimuli on adaptive response of children with sensory defensiveness. Methods : Subject of this study was a 6 years and 5 month old boy. The subject underwent a sensory integration (SI) treatment which was part of the SI treatment course administered by the Korean Sensory Integration Society, in 2011. The treatment goal and treatment plan had established based on the evaluation results. Treatment was done with 4 sessions and the adaptive responses of the subject were measured as outcome of the SI treatment. Results : During the SI treatment, the subject could participate in activities involving tactile stimulation without over-arousal. He also showed improved social interaction skills and his play was qualitatively extended. Conclusion : According to the results of this study, it was verified that sensory integrative intervention focused on proprioceptive-vestibular stimuli has positive effective on adaptive response for children with sensory defensiveness. For the future study, it is suggested to use standardized assessments in evaluation and provide information in changes of daily occupation as outcome data.

• Korean Journal of Applied Biomechanics
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• v.22 no.2
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• pp.209-217
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• 2012

The purpose of this study was to develop a turn-type treatment program which applies the principle of spotting and a roll-type treatment program that induces off-vertical axis. 29 collegiate students volunteered for this study. 12-week treatment programs were applied to both 15 students for turn-type treatment group and 14 students for roll-type treatment group. As an analytic tool, eye camera was employed to verify the treatment programs for a stimulus upon a turn, recovery after a stimulus upon a turn, and nystagmus that affects a vestibular system. Two-way ANOVA with repeated measures was applied to see the significant differences between the treatment groups, and between the test periods. For Post-Hoc Test, paired t-test was used to within the group and independent t-test was used to between the groups. The results indicated that roll-type treatment training has maximized a stimulus on nystagmyus during the stimulus by a roll. Turn-type treatment training has maximized a stimulus on nystagmyus right after a stimulus by a roll and significantly decreased the intensity of nystagmyus during the recovery. Both turn and roll type treatments have reduced the recovery time which from nystagmyus to a normal status. Roll-type treatment has showed a much shorter recovery time for nystagmyus than the roll-type treatment has. Based on the results of treatment programs developed in this study, we expect the treatment programs can be applied to treat dizziness and to improve the function of vestibular system as a rehabilitation tool.

• The Korean Journal of Pain
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• v.18 no.2
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• pp.218-221
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• 2005

This report describes a case of dizziness in a patient with trigeminal neuralgia that was caused by a vestibular schwannoma. A 60-year-old man with a history of pain on his left cheek, chin, molar and tongue for 5 months was diagnosed as suffering with trigeminal neuralgia of the left mandibular nerve, and this was caused by a left vestibular schwannoma. The diagnosis of the tumor was confirmed with magnetic resonance imaging (MRI), and so gamma knife surgery was performed 1 month later. At that time, the patient had been referred to the pain clinic due to allodynia on the tongue and gingival, and hypesthesia was also present on the left half of the face. Trigeminal nerve block with dehydrogenated alcohol and stellate ganglion block with 1% mepivacaine were performed and oral medication with diphenylhydantoin was started. The symptoms were alleviated after nerve block and oral medication. Dizziness, blurred vision and ataxia then developed from the 13th hospital day. We considered the symptoms as a side effect of diphenylhydantoin and we reduced the dose of diphenylhydantoin. However, the symptoms grew worse. Another brain MRI showed a slight increase of the tumor size and a mass effect with displacement of the adjacent organs, and hydrocephalus was also noted. This case shows the importance of considering the secondary symptoms that are due to brain tumor while treating trigeminal neuralgia. The changes of the brain tumors should also be considered along with the presence of new side effects.

• Journal of Korean Neurosurgical Society
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• v.42 no.3
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• pp.159-167
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• 2007

Vestibular schwannoma (VS) is a benign tumor typically originated in the schwann cell of vestibular nerve and usually accompany hearing symptom. Microsurgical removal and radiosurgery have a great role for the treatment of VS. Recently radiosurgery has been considered as an alternative or primary treatment for VS with the tremendous increase of patients who were treated with gamma knife radiosurgery (GKS) though microsurgery still takes the premier. By many published results, it is proved that GKS is a effective and noninvasive technique for VS, especially small sized tumors with satisfactory tumor control rate. The authors assumed that GKS can be expected to achieve satisfactory tumor control rate for small VS under 5cc in volume. A major interest regarding radiosurgery nowadays is to determine the optimal radiation dose for hearing preservation to improve the quality of life of patients. The more high radiation dose are used for effective tumor growth control, the more radiation-related complications like as hearing deficit, the impairment of other cranial nerve function are increased. Since 1990's the mean radiation dose for tumor margin was more than 18 Gy, but there were high complication rate in spite of good tumor growth control. After the year of 2000, under the influence of advanced neuro-imaging techniques and radiosurgical planning system which enable clinicians to do more precise planning, marginal dose for VS has been decreased to 12-13 Gy and the radiation-related complications has been reduced. But because there may be a unexpected radiation induced complications as time goes by after the latency period, optimal radiation dose for VS should be established on the basis of more long term follow-up observation.

• The Korean Journal of Physiology and Pharmacology
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• v.7 no.2
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• pp.59-63
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• 2003

The medial vestibular nucleus (MVN) neurons are controlled by excitatory synaptic transmission from the vestibular afferent and commissural projections, and by inhibitory transmission from interneurons. Spontaneous synaptic currents of MVN neurons were studied using whole cell patch clamp recording in slices prepared from 13- to 17-day-old rats. The spontaneous inhibitory postsynaptic currents (sIPSCs) were significantly reduced by the $GABA_A$ antagonist bicuculline ($20{\mu}M$), but were not affected by the glycine antagonist strychnine ($1{\mu}M$). The frequency, amplitude, and decay time constant of sIPSCs were $4.3{\pm}0.9$ Hz, $18.1{\pm}2.0$ pA, and $8.9{\pm}0.4$ ms, respectively. Spontaneous excitatory postsynaptic currents (sEPSCs) were mediated by non-NMDA and NMDA receptors. The specific AMPA receptor antagonist GYKI-52466 ($50{\mu}M$) completely blocked the non-NMDA mediated sEPSCs, indicating that they are mediated by an AMPA-preferring receptor. The AMPA mediated sEPSCs were characterized by low frequency ($1.5{\pm}0.4$ Hz), small amplitude ($13.9{\pm}1.9$ pA), and rapid decay kinetics ($2.8{\pm}0.2$ ms). The majority (15/21) displayed linear I-V relationships, suggesting the presence of GluR2-containing AMPA receptors. Only 35% of recorded MVN neurons showed NMDA mediated currents, which were characterized by small amplitude and low frequency. These results suggest that the MVN neurons receive excitatory inputs mediated by AMPA, but not kainate, and NMDA receptors, and inhibitory transmission mediated by $GABA_A$ receptors in neonatal rats.

• The Journal of Internal Korean Medicine
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• v.37 no.5
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• pp.893-902
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• 2016

Objective: To describe the effects of traditional Korean medicine on dizziness and gait disturbance arising after removal of a vestibular schwannoma. Methods: The patient was treated using Korean medical treatments, such as herbal medicines (Jaeumkunbi-tang-gagambang and Yookmijihwang-Insamyangyoung-tang-gagambang), acupuncture, and moxibustion. We measured the state and progress of this case with the Korean Vestibular Disorder Activities of Daily Living Scale (K-VADL), Berg Balance Scale (BBS), and a visual analogue scale (VAS). Results: After treatment, the K-VADL score decreased from 167 to 74 and the VAS score decreased from 10 to 5.7, while the BBS score increased from 3 to 42. Conclusion: Jaeumkunbi-tang-gagambang (滋陰健脾湯) and Yookmijihwang-Insamyangyoung-tang-gagambang(六味地黃湯 合 人蔘養榮湯 加減方) appear to be effective for controlling dizziness and gait disturbances occurring after removal of vestibular schwannomas.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.4
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• pp.353-358
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• 2014

Control of blood pressure is maintained by the interaction between the arterial baroreflex and vestibulosympathetic reflex during postural changes. In this study, the contributions of vestibular receptors and baroreceptors to the maintenance of blood pressure following acute hypotension were compared in terms of phosphorylated extracellular regulated protein kinase (pERK) expression in the nucleus tractus solitaries (NTS). Expression of pERK in the NTS was measured in conscious rats that had undergone bilateral labyrinthectomy (BL) and/or sinoaortic denervation (SAD) 5, 10, 20, and 40 min following acute hypotension induced by sodium nitroprusside (SNP) infusion. Expression of pERK increased significantly in the NTS in the control group following SNP infusion, and the expression peaked at 10 min after SNP infusion. The number of pERK positive neurons increased following SNP infusion in BL, SAD, and BL+SAD groups, although the increase was smaller than in control group. The BL group showed a relatively higher reduction in pERK expression than the SAD group, and the pERK expression in the NTS was localized to the caudal portion of the nuclei in the BL and SAD groups. These results suggest that the vestibular receptors may play a key role in maintaining blood pressure following acute hypotension; thus, the vestibular system may contribute to compensate for orthostatic hypotension.

• The Korean Journal of Physiology
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• v.16 no.1
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• pp.31-40
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• 1982

The present experiment was carried out to elucidate interrelation between the vestibular canals and the extraocular oblique muscles. In urethane anesthetized rabbits, excitatory or inhibitory effect of the canal was produced by three different methods; selective electrical stimulation of the ampullary nerve, bidirectional (ampullofugal or ampullopetal) lymphatic fluid flow, and rapid freezing of the canal. Changes of isometric tension as well as electro-myographic activity of the oblique muscles were recorded in the ipsilateral and contralateral eyes, by means of a polygraphic recorder, and the following results were obtained. 1) Electrical stimulation of a unilateral vertical or horizontal nerve caused contraction of superior oblique muscle and relaxation of inferior oblique muscle in the ipsilateral eye, and contraction of inferior oblique muscle and relaxation of superior oblique muscle in the contralateral eye. 2) Ampullofugal flow in a vertical canal and ampullopetal flow in a horizontal canal caused the oblique muscle responses which were identical to those responses produced by the electrical stimulation of the same canal nerve. 3) Rapid freezing of a vertical canal elicited the oblique muscle responses which were opposite to those caused by electrical stimulation of the same canal nerve. From the above experimental results, functional interrelation between the individual vestibular canal and bilateral extraocular oblique muscles were better elucidated. When these results were compared to those reported by previous investigators (Utzumi, Suzuki et al.), some important discrepancies were found between them. We ascribed such discrepancies to experimental errors of the previous investigators, since their results reflected theoretical contradictions in terms of vestibular eye movements.