• Journal of Korean Neurosurgical Society
• /
• v.55 no.4
• /
• pp.208-211
• /
• 2014

Recently, the increasing rates of facial nerve preservation after vestibular schwannoma (VS) surgery have been achieved. However, the management of a partially or completely damaged facial nerve remains an important issue. The authors report a patient who was had a good recovery after a facial nerve reconstruction using fibrin glue-coated collagen fleece for a totally transected facial nerve during VS surgery. And, we verifed the anatomical preservation and functional outcome of the facial nerve with postoperative diffusion tensor (DT) imaging facial nerve tractography, electroneurography (ENoG) and House-Brackmann (HB) grade. DT imaging tractography at the 3rd postoperative day revealed preservation of facial nerve. And facial nerve degeneration ratio was 94.1% at 7th postoperative day ENoG. At postoperative 3 months and 1 year follow-up examination with DT imaging facial nerve tractography and ENoG, good results for facial nerve function were observed.

• Korean journal of aerospace and environmental medicine
• /
• v.31 no.1
• /
• pp.9-12
• /
• 2021

Aircraft accidents caused by dizziness of aviation workers are so common that they account for 5% to 10% of the total, and in most cases, have fatal consequences. Therefore, it is essential to diagnose and treat the dizziness of aviation workers properly. Common diseases caused by abnormal vestibular function include benign paroxysmal positional vertigo, Meniere's disease, and vestibular neuritis. In this paper, we first proposed an overview of these diseases' pathophysiology, diagnosis, and treatment. Also, we evaluated the importance of these diseases in aerospace medicine and presented aerospace medical dispositions for aviation medical examiners.

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

• Journal of Korean Neurosurgical Society
• /
• v.66 no.2
• /
• pp.183-189
• /
• 2023

Objective : The facial nerve trace on the ipsilateral side of the vestibular schwannoma was reconstructed by diffusion tensor imaging tractography to identify the adjacent relationship between the facial nerve and the tumor, and to improve the level of intraoperative facial nerve protection. Methods : The clinical data of 30 cases of unilateral vestibular schwannoma who underwent tumor resection via retrosigmoid approach were collected between January 2019 and December 2020. All cases underwent magnetic resonance imaging examination before operation. Diffusion tensor imaging and anatomical images were used to reconstruct the facial nerve track of the affected side, so as to predict the course of the nerve and its adjacent relationship with the tumor, to compare the actual trace of the facial nerve during operation, verify the degree of coincidence, and evaluate the nerve function (House-Brackmann grade) after surgery. Results : The facial nerve of 27 out of 30 cases could be displayed by diffusion tensor imaging tractography, and the tracking rate was 90% (27/30). The intraoperative locations of facial nerve shown in 25 cases were consistent with the preoperative reconstruction results. The coincidence rate was 92.6% (25/27). The facial nerves were located on the anterior middle part of the tumor in 14 cases, anterior upper part in eight cases, anterior lower part in seven cases, and superior polar in one case. Intraoperative facial nerve anatomy was preserved in 30 cases. Among the 30 patients, total resection was performed in 28 cases and subtotal resection in two cases. The facial nerve function was evaluated 2 weeks after operation, and the results showed grade I in 12 cases, grade II in 16 cases and grade III in two cases. Conclusion : Preoperative diffusion tensor imaging tractography can clearly show the trajectory and adjacent position of the facial nerve on the side of vestibular schwannoma, which is beneficial to accurately identify and effectively protect the facial nerve during the operation, and is worthy of clinical application and promotion.

• International journal of advanced smart convergence
• /
• v.3 no.1
• /
• pp.20-24
• /
• 2014

To compare body signal, was designed the F-B function system on the body movement for the comfortable state. To detect subject of the normal state, was decided on the base of physical signal in the body movement. There are to detect the condition of Vision, Vestibular, Somatosensory and CNS. Vision condition was verified a variation of greater average (Vi-${\Phi}_{AVG-AVG}$) was presented slightly greater at $17.424{\pm}9.65$ unit. Vestibular condition was identified a variation of slightly greater average (Ve-${\Phi}_{AVG-AVG}$) was presented at $9.068{\pm}1.478$ unit. Somatosensory condition was checked a variation of smaller average (So-${\Phi}_{AVG-AVG}$) was presented slightly smaller at $2.79{\pm}0.419$ unit. CNS condition was confirmed a variation of diminutive smaller average (C-${\Phi}_{AVG-AVG}$) was presented slightly larger at $0.557{\pm}0.153$ unit. As the model depends on the F-B function system of body movement, average values of these perturbation were computed F-B function comparison data. These systems will be to infer a data algorithm and a data signal processing system for the evaluation of the stability.

• Journal of Biomedical Engineering Research
• /
• v.22 no.6
• /
• pp.487-496
• /
• 2001

In this study, a galvanic stimulator providing bipolar mode controlled by a PIC(peripheral interface controller) was constructed to evaluate vestibular function The maximum load and maximum current intensity of the constant current source were 3$k\Omega$ and 5mA. respectively. and it could Produce DC, sine wavers. or Pulse waves. Eve movements of 20 normal subjects by galvanic stimulation were analyzed using a commercial videooculogragh. During stimulating with DC for 30 sec. we recorded the response of eye movement with current intensity of 0.75. 1 2, and 3 mA. Nystagmus occurred to all the subjects when the galvanic stimulus intensity was larger than 2 mA. Average SPV(slow Phase eye movement velocity) and the number of nystagmus increased from 7.1 to 4.8 deg/sec and from 17 to 48, respectively, when the stimulus current increased from 0.75 to 3 mA. All the fast eye movement of the nystagmus were the direction of the negative electrode. The asymmetry which means the difference between right- and left-eye movements decreased when the stimulus intensity increased. It is expected that this study would be useful in evaluating vestibular function and in studying basic Physiology mechanism of vestibular ocular reflex by galvanic stimulus .

• Proceedings of the KIEE Conference
• /
• 1994.07a
• /
• pp.582-584
• /
• 1994

A sinusoidal rotatory chair system using a self-tuning and following control by a fuzzy was designed to evaluate the vestibular function and to apply to a robot driving power system. The experimental results by the sinusoidal rotatory chair system were pretty good and whitch had smaller then ${\pm}210$ pulse error on the ${\pm}810^{\circ}$ sinusoidal rotation at 0.12 Hz by using a 850W DC servo motor. As a results, the sinusoidal rotatory chair system may be useful to evaluate the vestibular function in the field of medicine, and it can be used to robotics or a numerical control system (NC) on the industry if the the obtained control method and the system are adapted for a channel.

• Science of Emotion and Sensibility
• /
• v.1 no.1
• /
• pp.181-197
• /
• 1998

전정기관은 자세의 조절에 관여하지만, 전정기관의 손상은 현기증 및 자세부조화를 초래한다. 본 연구에서는 현기증의 원인을 규명할 목적으로 전정기능을 평가할 수 있는 정현파 회전자극시스템을 개발하고자 하였다. 정현파 회전자극시스템은 회전의자와 구동 및 분석프로그램으로 구성하였으며, DC 서보모터로 구동되는 회전의자는 0.01-0.64 Hz의 주파수범위에서 60 ˚/sec의 초고속도로 정현파 회전한다. 현기증 환자에서 전정기능을 평가하기 위하여 전정안구반사, 시운동성 전정안구반사 및 시각의 억제에 의한 전정안구반사를 측정하여 안구운동의 이득, 위상, 대칭성 등을 산출하도록 정현파 회전자극시스템을 개발하였으며, 정상 성인에서 시험한 결과 신뢰성있는 성적을 얻었다. 따라서 본 시스템은 현기증 환자의 진단 및 치료정도를 판정할 수 있으르로 임상적으로 널리 사용할 수 있을 것으로 사료된다.

• International Journal of Oral Biology
• /
• v.34 no.4
• /
• pp.215-222
• /
• 2009

Medial vestibular nucleus (MVN) neurons are involved in the reflex control of the head and eyes, and in the recovery of vestibular function after the formation of peripheral vestibular lesions. In our present study, whole cell patch clamp recordings were carried out on MVN neurons in brainstem slices from neonatal rats to investigate the actions of a group I metabotropic glutamate receptor (mGluR) agonist upon synaptic transmission and ionic currents. Application of the mGluR I agonist (S)-3,5- dihydroxyphenylglycine (DHPG) increased the frequency of miniature inhibitory postsynaptic currents (mIPSCs) but had no effect upon amplitude distributions. To then identify which of mGluR subtypes is responsible for the actions of DHPG in the MVN, we employed two novel subtype selective antagonists. (S)-(+)-$\alpha$-amino-a-methylbenzeneacetic acid (LY367385) is a potent competitive antagonist that is selective for mGluR1, whereas 2-methyl-6-(phenylethynyl)-pyridine (MPEP) is a potent noncompetitive antagonist of mGluR5. Both LY367385 and MPEP antagonized the DHPG-induced increase of mIPSCs, with the former being more potent. DHPG was also found to induce an inward current, which can be enhanced under depolarized conditions. This DHPG-induced current was reduced by both LY367385 and MPEP. The DHPG-induced inward current was also suppressed by the PLC blocker U-73122, the $IP_3$ receptor antagonist 2-APB, and following the depletion of the intracellular $Ca^{2+}$ pool by thapsigargin. These data suggest that the DHPG-induced inward current may be mainly regulated by the intracellular $Ca^{2+}$ store via the PLC-$IP_3$ pathway. In conclusion, mGluR I, via pre- and postsynaptic actions, may modulate the excitability of the MVN neurons.

• Journal of Korean Neurosurgical Society
• /
• v.42 no.6
• /
• pp.450-454
• /
• 2007

Objective : The aim of this study was to identify the anatomical location and course of the facial nerve (FN) and their relationship to the tumor size in surgically treated vestibular schwannomas. Methods : A retrospective study was conducted on 163 patients who had been treated by the microsurgical resection for a newly diagnosed vestibular schwannoma between 1995 and 2005 (mean age of 46.1 years; 108 females and 55 males). Surgery was carried out via retrosigmoid approach in all patients with the electromyographic monitoring for the FN function. The anatomical location and course of the FN along the tumor surface were verified in each patient during the microsurgery, and were classified into 4 groups : 1) the FN displaced along the ventral and superior surface of the tumor (VS); 2) the ventral and central (VC); 3) the ventral and inferior (VI); and 4) the dorsal (Do). Results : The FN displacement was identified as the followings : VS in 91 patients (55.8%); VC in 57 (35.0%); VI in 14 (8.6%); and Do in 1 (0.6%). In the subgroup with tumors less than 2 cm in diameter (n=23), the FN was displaced along the ventral and central surface of the tumor in the majority (65.2%), whereas, in the patients with tumors larger than 2cm (n=140), it was displaced along the ventral and superior surface most frequently (59.3%). Conclusion : The FN can be displaced variably in vestibular schwannomas, and most frequently along the ventral and superior surface of the tumor, especially in large ones.