• Journal of Korean Neurosurgical Society
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• v.57 no.4
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• pp.292-294
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• 2015

Vestibular schwannoma (VS) usually present the widening of internal auditory canal (IAC), and these bony changes are typically limited to IAC, not extend to temporal bone. Temporal bone invasion by VS is extremely rare. We report 51-year-old man who revealed temporal bone destruction beyond IAC by unilateral VS. The bony destruction extended anteriorly to the carotid canal and inferiorly to the jugular foramen. On histopathologic examination, the tumor showed typical benign schwannoma and did not show any unusual vascularity or malignant feature. Facial nerve was severely compressed and distorted by tumor, which unevenly eroded temporal bone in surgical field. Vestibular schwannoma with atypical invasion of temporal bone can be successfully treated with combined translabyrinthine and lateral suboccipiral approach without facial nerve dysfunction. Early detection and careful dissection of facial nerve with intraoperative monitoring should be considered during operation due to severe adhesion and distortion of facial nerve by tumor and eroded temporal bone.

• Animal cells and systems
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• v.4 no.3
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• pp.215-221
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• 2000

Our anatomical and behavioral studies of embryonic rats that developed in microgravity suggest that the vestibular sensory system, like the visual system, has genetically mediated precesses of development that establish crude connections between the periphery and the brain. Environmental stimuli also regulate connection formation including terminal branch formation and fine-tuning of synaptic contacts. Axons of vestibular sensory neurons from grabistatic as well as linear acceleration receptors reach their targets in both microgravity and norm81 gravity, suggesting that this is a genetically regulated component of development. However, microgravity exposure delays the development of terminal branches and synapses in gravistatic but not linear acceleration-sensitive neurons and also produces behavioral changes. These latter changes reflect environmentally controlled processes of development.

• Journal of Korean Neurosurgical Society
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• v.38 no.3
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• pp.227-230
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• 2005

Hearing loss in the contralateral functioning ear is a rare and distressing complication after vetibular schwannoma removal. Various possible mechanisms have been proposed, however, the etiology of hearing loss is not clear. Fortunately, this is an extremely rare occurrence, sporadic case reports have appeared in the literatures. We report two cases of acute contralateral hearing loss after vestibular schwannoma removal and discuss the possible mechanisms of the phenomenon. Although permanent deafness may result, in our cases, the hearing loss was temporary, returning to near preoperative level within one month. The etiology of hearing loss in one case is thought to be cerebrospinal fluid leakage. However, in the other case, the cause of hearing loss is not clear. A better understanding of these events may lead to preventive measures to avoid contralateral hearing loss after vestibular schwannoma removal.

• Korean Journal of Audiology
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• v.23 no.3
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• pp.167-172
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• 2019

Differentiating central vestibulopathy from more common vestibular disorders is crucial because it often necessitates different treatment strategies, and early detection can help to minimize potential complications. Isolated nodular infarct is one of the central brain lesions that can mimic peripheral vertigo. We present a case of isolated nodular infarct that had been misdiagnosed as vestibular neuritis on the contralateral side at the initial evaluation. The patient was successfully treated with anticoagulants and antihyperlipidemic agents. Clinicians should keep in mind that some causes of central vertigo mimic peripheral vestibulopathy at the early stage.

• Journal of Audiology & Otology
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• v.23 no.3
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• pp.167-172
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• 2019

Differentiating central vestibulopathy from more common vestibular disorders is crucial because it often necessitates different treatment strategies, and early detection can help to minimize potential complications. Isolated nodular infarct is one of the central brain lesions that can mimic peripheral vertigo. We present a case of isolated nodular infarct that had been misdiagnosed as vestibular neuritis on the contralateral side at the initial evaluation. The patient was successfully treated with anticoagulants and antihyperlipidemic agents. Clinicians should keep in mind that some causes of central vertigo mimic peripheral vestibulopathy at the early stage.

• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.6
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• pp.524-530
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• 2002

A control of the body posture and movement is maintained by the vestibular system, vision, and proprioceptors. Afferent signals from those receptors are transmitted to the vestibular nuclear complex, and the efferent signals from the vestibular nuclear complex control the eye movement and skeletal muscle contract. The postural disturbance caused by loss of the vestibular function results in nausea, vomiting, vertigo and loss of craving for life. The purpose of this study is to develop a off-vertical rotatory system for evaluating the function of semicircular canals and otolith organs, selectively, and visual stimulation system for- stimulation with horizontal, vortical and 3D patterns. The Off-vortical axis rotator is composed of a comportable chair, a DC servo-motor with reducer and a tilting table controlled by PMSM. And a double feedback loop system containing a velocity feedback loop and a position feedback loop is applied to the servo controlled rotatory chair system. Horizontal, vertical, and 3D patterns of the visual stimulation for applying head mounted display are developed. And wireless portable systems for optokinetic stimulation and recording system of the eye movement is also constructed. The gain, phase, and symmetry is obtained from analysis of the eye movement induced by vestibular and visual stimulation. Detailed data were described.

• The Journal of Korean Physical Therapy
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• v.26 no.5
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• pp.365-371
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• 2014

Purpose: The aim of this study is to examine the effects of training in vestibular sensory stimulation on balance and gait of stroke patients. Methods: Twenty patients were randomly assigned to either the experimental group (n=10) or the control group (n=10). Patients in the experimental group received rotational stimulation training, vertical-horizontal stimulation training, gait training on a flat surface with vestibular sensory stimulation, and gait training on soft ground with vestibular sensory stimulation. Patients in the control group received general treadmill gait training. The intervention was applied four times per week, 25 minutes each time, for a period of four weeks. We measured Berg Balance Scale (BBS), Biodex Balance System, Timed up to Go (TUG) test and Dynamic Gait Index (DGI) to evaluate balance and gait ability. Results: BBS differed significantly in both groups between before and after the intervention (p<0.05) and changes in BBS after the intervention differed between the two groups (p<0.05). According to the Biodex Balance System test result, only the experimental group showed significant changes in balance in the conditions of static eyes open (SEC), dynamic eyes open (DEO), and dynamic eyes closed (DEC) (p<0.05). TUG test results differed significantly between prior to and after the training in both the experimental group and the control group (p<0.05) and changes in TUG after the intervention differed significantly between the two groups (p<0.05). DGI results showed significant change after the intervention in the experimental group only (P<0.05). Conclusion: Training in vestibular sensory stimulation was effective in improving static-dynamic balance and gait ability of stroke patients.

• Journal of Korean Neurosurgical Society
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• v.42 no.4
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• pp.286-292
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• 2007

Objective : Gamma Knife Stereotactic Radiosurgery (GK SRS) has become an important treatment modality for vestibular schwannomas. We evaluated the tumor control rate, patterns of tumor volume change and preservation of hearing following low-dose radiation for vestibular schwannomas in a homogeneous cohort group in which the mean marginal dose was 12 Gy. Methods : A total of 59 patients were enrolled in this study. All enrolled patients were followed-up for at least 5 years and the radiation dose was 11-13 Gy. Regular MRI, audiometry and clinical evaluations were done and tumor volumes were obtained from MRI using the OSIRIS program. Results : The tumor control rate was 97%. We were able to classify the patterns of change in tumor volume into three categories. Transient increases in tumor volume were detected in 29% of the patients and the maximum transient increase in tumor volume was identified at 6 to 30 months after GK SRS. The transient increases in tumor volume ranged from 121% to 188%. Hearing was preserved in 4 of the 12 patients who had serviceable hearing prior to treatment. There were no other complications associated with GK SRS. Conclusion : Low-dose GK SRS was an effective and safe mode of treatment for vestibular schwannomas in comparison to the previously used high-dose GK SRS. Transient increases in tumor volume can be identified during the follow-up period after low-dose GK SRS for vestibular schwannomas. Physicians should be aware that these increases are not always indicative of treatment failure and that close observation is required following treatments. Unfortunately, a satisfactory hearing preservation rate was not achieved by reducing the radiation dose. It is thought that hearing preservation is a more sophisticated problem and further research is required.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.8 no.1
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• pp.43-50
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• 2010

Purpose : The objective of this study is to effect of an aquatic rotation control and obstacle avoidance when conducted underwater on hemiplegia patient's balance ability and vestibular function. Methods : Twelve hemiplegia patients participated and were randomly assigned to a control group(I) with standard physical therapy and an aquatic group(II) with an aquatic rotation control, obstacle avoidance and standard physical therapy as well. The aquatic group trained using a Halliwick rotation control and obstacle avoidance through 3 times per week over 6 weeks. For all subjects, vestibular function, their balance, the change of electrooculogram (EOG), the change of accelerometer axis and torsiometer according to visual sense, vestibular sense with galvanic vestibular stimulation (GVS) or not during leg close stance were measured. Results : The EOG in the vertical and horizontal (p<0.05) were both significantly lowered. The change was significantly lower in the trajectory range of motion of trunk and spine with torsiometer when leg close stand (p<0.01) and leg close stand with GVS (p<0.01). The centre of gravity accelerated, there were reduced significantly difference X and Y axis of accelerometer during the closing of the leg without vision (p<0.05). There were reduced significantly difference X and Z axis of accelerometer during the closing of the leg with GVS (p<0.05). There were reduced significantly difference X and Z axis of accelerometer during the closing of the leg and close eyes with GVS (p<0.05). Conclusion : The balance ability, vestibular system and postural control is improved.

• Physical Therapy Korea
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• v.19 no.2
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• pp.39-47
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• 2012

The purpose of this study is to examine the influence of a horse riding simulator and galvanic vestibular stimulation on improving the ability to balance posture and proprioception. Thirty healthy adults participated and were randomly assigned to a horse riding simulator group ($n_1$=10), galvanic vestibular stimulation (GVS) group ($n_2$=10), control group ($n_3$=10). Experiment groups were trained 3 times per week over 6 weeks. The ability to balance posture was measured by force plate and proprioception was measured by Joint position sense. The following results were obtained. the changes of balance index were significant interaction in each group in accordance with the experiment time in 0, 3 and 6 weeks (p<.05). All groups showed the most decreasing pattern compared with the control group. But was not statistically significant. Proprioception was significant interaction in each group in accordance with the experiment time (p<.05). All groups showed the most decreasing pattern compared with the control group. The above results indicated that the 6 weeks horse riding simulator and galvanic vestibular stimulation training demonstrated positive effects in the ability to balance posture and proprioception. These results suggest that the horse riding simulator and galvanic vestibular stimulation training could be therapeutic intervention that can improve balance and postural control.