• Journal of Korean Neurosurgical Society
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• 제55권4호
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• pp.208-211
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• 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.

• Journal of Korean Neurosurgical Society
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• 제30권11호
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• pp.1308-1313
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• 2001

Object : The goals of radiosurgery include preservation of neurological function and prevention of tumor growth. We document the results of gamma-knife radio-surgery for vestibular schwannoma. Method & Object : Eighty-two patients underwent stereotactic radiosurgery for an vestibular schwannoma from October, 1994 to December, 2000. Sixty-five of these patients were followed up for radiological and clinical evaluation. As pregamma-knife modality, surgical resection were done in 23 patients,and V-P shunt in 2 patients. Initial symptoms were headache(n=45), dizziness(n=16), tinnitus(n=17). While normal facial function(House-Brackmann grade 1) was present in 48 patients(73.8%), other patients showed grade 2 function in 8, grade 3 function in 7,and grade 4 function in 2. The Gardner/Robertson scale was used to code hearing function. Male to female ratio was 1:3. Mean tumor volume was $7.98cm^3$. Mean dose delivered to the tumor margin was 14.2Gy,and mean maximal dose was 28.3Gy. Results : Mean follow-up duration of 19.9 months. Thirty-five showed decrease(53.8%) in size, 19 patients(29.2%) stationary, 3(4.6%) initial decrease follow up increase, 5(7.6%) initial increase follow up decrease,and 59 patients (90.8%) were well controlled. Two patients experienced transient facial neuropathy, one transient trigeminal neuropathy, and one transient hearing deterioration. After gamma-knife radiosurgery, ventriculoperitoneal shunt was done in 4 patients. Conclusions : Gamma-knife radiosurgery can be used to treat postoperative residual tumors as well as in patients with concomitant medical problems in patients with preserved hearing function. Gamma-knife radiosurgery is safe and effective method to treat small, medium sized(less than 3cm in extracanalicular diameter), intracanalicular vestibular schwannoma, associated with low rate of cranial neuropathy.

• Journal of Korean Neurosurgical Society
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• 제40권5호
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• pp.336-341
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• 2006

Objective : The authors conducted a retrospective study to evaluate the preservation rates of serviceable hearing and to determine its prognostic factors after gamma knife stereotactic radiosurgery[GK SRS] in the patient with vestibular schwannomas. Methods : Between December 1997 and March 2005, 54 patients with a sporadic vestibular schwannoma and serviceable hearing [Gardner Robertson grade I-II] were enrolled in this study. Electronic database of medical records and radiological examinations before and after GK SRS were investigated to the last follow up. The mean marginal dose was $12.3{\pm}0.7Gy$. The mean maximum dose delivered to the tumor center was 24.7Gy [$22{\sim}30Gy$]. The median tumor volume was 2cc [$0.1{\sim}9.1cc$]. The median follow-up period of magnetic resonance[MR] imaging was 31 months [$6{\sim}99\;months$], and the mean follow-up period of audiometry was 24 months [$4{\sim}70\;months$]. Results : The tumor control rate was 100% in the patients with the follow up period more than 2 years. The trigeminal and facial nerve preservation rates were 98% and 100%, respectively. Twenty-eight [52%] of the 54 patients preserved serviceable hearing and 16 [30%] patients retained their pre-GK G-R grade level after GK SRS. In the univariate and multivariate analysis, there was no significant prognostic factor in preservation of the serviceable hearing. Conclusion : The hearing preservation rate is still unsatisfactory compared with the results of other cranial nerve preservation and tumor control in the treatment of vestibular schwannoma by GK SRS. More sophisticated strategy during and after GK SRS is necessary to improve long-term hearing preservation.

• Journal of Korean Neurosurgical Society
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• 제42권6호
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• pp.450-454
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• 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.

• Journal of Korean Neurosurgical Society
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• 제66권4호
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• pp.456-464
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• 2023

Objective : This study aims to investigate the incidence of vestibular schwannoma (VS) and demographic characteristics in Korea using population-based National Health Insurance Service data. Methods : This study analyzed Korean National Health Insurance Service data from 2005 to 2020, based on the International Classification of Diseases, 10th version, Clinical Modification codes D333 and D431. Only those patients who had undergone magnetic resonance imaging and audiologic tests were considered definitive cases. Demographic variables included age, sex, treatment modality, hypertension, diabetics, dyslipidemia, smoking history, alcohol history, and income status. Results : The total number of VS patients was 5751. The average incidence rate was 0.71 per 100000 from 2005 to 2020, and the annual incidence rate increased from 0.33 in 2005 to 1.32 in 2019 but decreased to 0.80 in 2020. Incidence was highest in those aged 60-69 years (1.791) and lowest in those younger than 20 years (0.041). Incidence was higher in females, and the number of patients who received radiosurgery (46.64%) was largest compared to the wait and scan group (37.96%), microsurgery group (12.85%), or the group who received both (2.56%). Diabetes, dyslipidemia, and alcohol consumption increased the risk of VS, while cigarette smoking reduced the risk of VS. Conclusion : The incidence of VS exhibited an increasing trend from 2005 to 2019. Radiosurgery (46.64%) was the most common treatment modality. Diabetes, dyslipidemia, and alcohol consumption increased the risk of VS, while cigarette smoking reduced the risk of VS.

• Journal of Korean Neurosurgical Society
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• 제45권2호
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• pp.103-106
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• 2009

Intracranial schwannomas preferentially arise from the vestibular branch of the eighth nerve, and rarely from the trigeminal nerve, facial nerve, and lower cranial nerves. Anterior cranial fossa schwannomas are extremely uncommon and few details about them have been reported. The patient was a 39-year-old woman whose chief complaints were anosmia and frontal headache for 2 years. The gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) showed an extra-axial mass from ethmoid sinus to right frontal base region near the midline, with solid enhancement in lower portion and multicystic formation in upper portion. The tumor was totally resected via basal subfrontal approach. At operation, the tumor had cystic portion with marginal calcification and the anterior skull base was destructed by the tumor. The olfactory bulb was involved, and the tumor capsule did not contain neoplastic cells. The histopathological diagnosis was schwannoma. We report a rare case of anterior cranial fossa schwannoma with literature review.

• 한국방사선학회논문지
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• 제17권2호
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• pp.243-248
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• 2023

본 연구에서는 청신경초종 질환에서 방사선 수술 시 유리선량계를 이용하여 손상위험장기들의 피폭으로 인해 발생하는 2차 발암률을 분석하고자 한다. 인체 조직 등가 물질의 소아 팬텀을 사용하여, 종양의 체적은 0.506 cm³, 1.008 cm³, 2.032 cm³ 총 3개의 체적으로 설정하였고, 평균 선량은 18.4 ± 3.4 Gy로 방사선수술계획을 수립하였다. 수술 장비의 테이블에 인체 팬텀을 장착시킨 후 유리선량계를 우안, 좌안, 갑상샘, 흉선, 오른쪽 폐, 왼쪽 폐에 위치시켜 각각 피폭선량을 측정하였다. 본 연구에서 가장 큰 종양체적인 2.032 cm³의 청신경초종 질환에서 감마나이프 방사선 수술 시 손상위험장기의 피폭으로 인한 2차 암 발생률을 유리선량계로 측정한 그 결과는 10,000명 당 1.11명의 2차 암이 발생될 수 있는 것으로 계산되었다. 본 연구는 정위적 방사선 수술 시 발생할 수 있는 2차 방사선 피폭선량의 위험성을 연구하여 향후 방사선의 확률적 영향과 관련된 방사선 장해분야에 기초자료로 활용될 것이라 사료된다.

• Journal of Korean Neurosurgical Society
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• 제30권6호
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• pp.755-760
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• 2001

Objective : To determine the feasibility of translabyrinthine approach in the vestibular schwannoma patients, the authors reviewed eighteen consecutive cases, focusing at their functional outcome and operative complications. Materials and Method : To evaluate the functional outcome, we reviewed preoperative radiological findings such as size of tumors and location of jugular bulb as well as the preoperative neurological status including audiometric analysis and cranial nerve function in 18 patients, diagnosed as vestibular schwannoma. Also the surgical outcome was evaluated according to the functional preservation of facial nerve and incidence of the surgical complication as well as the extent of surgical resection. Results : The age of patients ranged from 21 to 62 years, with a mean of 50 years. Of 18 patients operated in our center by the translabyrinthine approach, wide exposure with total removal of the mass was possible in 16 cases (88.8%). The facial nerve was anatomically preserved in 88.8%. At six-month follow-up, facial nerve function was good(Grade I-II) in 15 patients(83%) and acceptable(I-IV) in all patients. Although the jugular bulb was highly placed is five patients, gross total resection was possible without facial nerve injury in all patients by the translabyrinthine approach. One patient experienced CSF leakage after surgery, but there was no patient with disabling deficit. Conclusion : Use of the translabyrinthine approach for removal of vestibular schwannomas resulted in good anatomical and functional preservation of the facial nerve, with minimal incidence of morbidity and no mortality. In cases of high jugular bulb impacted into mastoid bone, total removal was possible by displacing the jugular bulb with Surgicel cellulose and placement of bone wax.

• Journal of Korean Neurosurgical Society
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• 제42권3호
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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.

• 대한한방내과학회지
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• 제37권5호
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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.