7075-T651 AI 合金에 있어서 物理的 微小 表面 疲勞균열 成長擧動에 관한 硏究

신용승(Yong-Seung Shin),서성원(Seong-Won Seo),유헌일(Heon-IL Yoo) Korean Society for Precision Engineering 1992 한국정밀공학회지 Vol.9 No.1

경접형골동접근법에 의한 뇌하수체종양의 재수술

고영초,유헌,김창현,황도윤,장진순,박효일,Koh, Young-Cho,Yoo, Heon,Kim, Chang-Hyun,Whang, Do-Yun,Jang, Jin-Soon,Park, Hyo-Il 대한신경외과학회 2000 Journal of Korean neurosurgical society Vol.29 No.7

Objective : The results of secondary transsphenoidal surgery(TSS) for either residual or recurring pituitary adenomas have been reported to be unfavorable. To evaluate the effectiveness of secondary TSS, we analyzed the surgical results of residual or recurred pituitary adenomas in patients who underwent secondary TSS from 1992 to 1998. Material and Methods : Among the 95 patients who underwent TSS during this period, 14(15%) received repeated TSS. Two of the 14 patients underwent three TSS. Among the 11 patients with pituitary adenomas, three had nonfunctioning tumors ; six prolachnomas ; two GH-secreting adenomas. The remaining three patieats had craniopharyngioma, pituitary abscess and hemangioendothelioma respectively. The interval between the two surgical procedures ranged from one week to 33 months(mean ; 12 months). Causes of the secondary TSS were tumor recurrence in 11 patients, intentional staged operation in three, persistent disease despite medical therapy and CSF leak after initial operation in one respectively. Treatments prior to secondary TSS were medical treatment only in eight patients. Results : During the repeated operationtss some adhesion was noted in septal mucous membrane. The sphenoid cavity was filled with fibrous tissue which correlated with the methods of reconstruction of the sellar floor at the previous operation. There was no statistically significant difference in success rate of surgery between the initial and the second TSS(86% vs 81%). The complication rate was similar between the two procedures. There was no statistically significant factors affecting the results of second TSS. Conclusion : Transsphenoidal reoperation was regarded as a suitable approach for treating recurrent pituitary adenomas in spite of some degree of operative difficulties. In patients with transsphenoidally resectable tumor residuals or recurrences confirmed by magnetic resonance imaging, remissions can be obtained with high probability, especially in secondary surgery after an staged decompression.

하후두부 접근법과 후경추체 접근법에 의한 거대 경정맥공 신경초종의 제거술과 동반된 합병증 - 증례보고 -

고성범,고영초,유헌,박시영,박효일,Koh, Sung-Bum,Koh, Young-Cho,Yoo, Heon,Park, Si-Young,Park, Hyo-IL 대한신경외과학회 2001 Journal of Korean neurosurgical society Vol.30 No.9

Schwannomas of the jugular foramen, originating from the glossopharyngeal nerve, vagus and accessory nerve represent approximately 0.17-0.72% of all intracranial tumor, and consists of 1.4-2.9% of all intracranial schwannomas. The clinical presentation of these tumors varies significantly according to originated nerve and it's growth pattern. Magnetic resonance(MR) image and temporal bone computed tomography(CT) scan have a major role for diagnosis of such tumor. The treatment of choice is total resection whenever possible. Generally, suboccipital approach is sufficient for the removal of the tumor, but in case with large size, combination of resection of petrous part of temporal bone with or without transection of sigmoid sinus is may be necessory. We have recently experienced one case of giant jugular foramen schwannoma and postoperative fatal complication in a 34-year-old male who was treated with combined posterior petrous and suboccipital approach with transection of sigmoid sinus

두개골 유아 근섬유증 - 증례보고 -

박병준,고영초,유헌,이채혁,박효일,Park, Byoung Jun,Koh, Young Cho,Yoo, Heon Yoo,Lee, Chea Heuck,Park, Hyo Il 대한신경외과학회 2000 Journal of Korean neurosurgical society Vol.29 No.3

Infantile myofibromatosis is a rare and benign myofibroblastic tumor that may occur in either solitary or multicentric form in the soft tissue of infants. A 13-month-old girl presented with a painless firm mass, measuring $2.5{\times}2.5cm$ in the right temporal area. Skull X-ray and CT scan revealed a well enhancing soft tissue tumor with a round skull defect and sclerotic margin. The tumor was totally excised with curettage of the skull defect followed by cranioplasty. Pathology was confirmed to be a solitary infantile myofibromatosis. We report this rare solitary infantile myofibromatosis of the temporal bone with review of the pertinent literature.

임상 : 비소세포암의 뇌전이에 대한 개두술 및 종양절제술 후 보조적 치료의 결과

김영준 ( Young Zoon Kim ),유헌 ( Heon Yoo ),양희석 ( Hee Seok Yang ),신상훈 ( Sang Hoon Shin ),이승훈 ( Seung Hoon Lee ) 대한뇌종양학회 2006 대한뇌종양학회지 Vol.5 No.2

Purpose:This study was aimed to compare the survival and recurrence according to postoperative adjuvant therapeutic modalities for brain metastasis. Methods:From June 2002 to December 2005, 49 patients with brain metastasis from non-small cell lung cancer(NS CLC) underwent adjuvant systemic chemotherapy or whole brain radiotherapy(WBRT) or both after metastatectomy. In Group A, 13 patients were treated with systemic chemotherapy and WBRT after brain surgery. In Group B, 11 patients were treated with WBRT only after brain surgery and in Group C, 25 patients with systemic chemotherapy only after brain surgery. Results:Median survival times were 12.7 months in Group A, 5.0 months in Group B, and 11.6 months in Group C. Median time to progression of local disease were 7.7 months in Group A, 4.0 months in Group B, and 4.4 months in Group C. There were no statistical differences in survivals and local recurrences according to postoperative adjuvant therapeutic modalities. Favor factor for the survival was RPA class I only. And favor factors for the local recurrence were metachronoous presentation, RPA class, extensive surgical resection, gender and Sawaya grade. Conclusion:In this study, we suggest that postoperative systemic chemotherapy for brain metastasis after brain metastatectomy, instead of adjuvant WBRT, can control primary cancer and brain disease simultaneously and prevent neurocognitive dysfunction originating from WBRT.

성인 쿠싱병의 치료성적과 예후인자

박철기,황승균,곽호신,유헌,정영섭,백선하,김동규,정희원,김성연,홍승관,Park, Chul-Kee,Hwang, Sung Kyun,Gwak, Ho-Shin,Yoo, Heon,Chung, Young Seob,Paek, Sun Ha,Kim, Dong Gyu,Jung, Hee-Won,Kim, Seong Yeon,Hong, Seung Kuan 대한신경외과학회 2000 Journal of Korean neurosurgical society Vol.29 No.10

Objectives : The authors analyzed the surgical series of Cushing's disease to evaluate the proper treatment policy and to verify the possible prognostic factors. Material and Methods : Of 50 patients diagnosed as Cushing's disease and operated at Department of Neurosurgery of our institute between 1988 and 1999, 48 patients with available medical records were analyzed retrospectively. Mean follow-up period was 48 months(3 to 109 months). Preoperative diagnosis was made after evaluating the patients with multiple-stage endocrinological studies and 31 selective patients were evaluated with inferior petrosal sinus sampling(IPSS). Magnetic resonance imaging(MRI) and/or high resolution computerized tomography(CT) was done in all patients. A total of 51 transsphenoidal adenomectomy(TSA) were performed including 3 revision for initial surgical failure cases. Remission was decided on the basis of both endocrinological criteria and clinical status. Radiation and/or ketoconazole therapy were applied to failed cases. For the verification of prognostic factors, the authors evaluated the statistical significance of multiple variables over remission rate by chi-square test. Result : Sensitivity of IPSS for central localization was 93.5% which was better than that of MRI(87.5%). But for lateralization, it was 72.4% for IPSS versus MRI 90.5%. Success rate of TSA was 82%(42/51) and recurrence rate was 9%(4/48). When including adjuvant treatments for surgically failed cases, overall success rate was 89.6% and all of 3 reoperated cases(TSA) due to recurrence were successful. Significant complication occurred in 7.8%(4/51) after TSA including hypopituitarism, diabetes insipidus, and visual loss. Non-existence of tumor in MRI and prolonged symptom duration(>3 years) were significant prognostic factors. Conclusion : TSA can be considered as initial treatment for Cushing's disease. In surgically failed cases, multiple treatment modality may improve the overall outcome and repeated TSA for recurrent cases seem to provide similar success.

신경종양학 분야에서 항경련제의 임상적 적용

김영준 ( Young Zoon Kim ),유헌 ( Heon Yoo ) 대한뇌종양학회·대한신경종양학회·대한소아뇌종양학회 2009 대한뇌종양학회지 Vol.8 No.1

Epileptic seizures are common in patients with brain tumor, even if the tumor is under control. Miltiple factors affect the mechanism of seizure in brain tumors, including changes of morphology, pH, ion level, amino acid, and enzyme in peritumoral brain tissue, role of glutaminergic N-methyl-D-aspartate(NMDA) receptor, damage of peritumoral brain immunology, and change of intercellular communication. Additionally, traditional anti-epileptic drug(AED) can cover only a few mechanisms of epileptogensis in brain tumors. Tumor progression or recurrence may make seizures reappear during AED. Owing to combined treatment modality with chemotherapy or other drugs, insufficient levels of AEDs have been reported in the many patients with brain tumor. Therefore, comprehensive understand about pathophysiology of epileptogensis in the brain tumor and drug interactions between AEDs and other drugs, which are widely used in the field of neurooncology, can give an aids to manage brain tumor related epilepsy.

종양내 출혈로 진단된 청신경 초종 -증례보고-

고영초 ( Young Cho Koh ),유헌 ( Heon Yoo ),권오기 ( O Ki Kwon ),김용만 ( Yong Man Kim ),주미 ( Mee Joo ),이기재 ( Ghi Jai Lee ) 대한뇌종양학회 2002 대한뇌종양학회지 Vol.1 No.1

The authors report unusual presentation of a vestibular schwannoma in a 53-year-old man, who presented with sudden onset of severe headache and, vomiting followed by left peripheral type facial palsy two weeks prior to admission. He had been well except for a longstanding left hearing difficulty, which had been considered as an aging process. In addition, he had mitral valve replacement surgery two years prior to admission , for which he had taken anticoagulant(Warfarin 2mg) everyday with regular monitoring of coagulability. Plain CT scan on admission demonstrated a 3×4×3cm sized high density mass at the left cerebellopontine angle with erosion and widening of the left internal auditory meatus. Brain MRI showed a heterogenous signaled mass with high signal on T1WI with little contrast enhancement and low signal on T2WI suggestive of multistaged hematomas within the peripherally enhancing tumor. Under the impression of intratumoral repeated bleeding in a patient with preexisting vestibular schwannoma, left suboccipital craniectomy was undergone to remove a large extraaxial tumor, mixed with large amount of hemorrhages. Postoperative course was uneventful except for persistent left facial palsy and hearing loss. Postoperative anticoagulation was started on the 5th postoperative day.

수술현미경에서의 다중형광영상을 이용한 뇌종양과 혈관영상 검출 시스템 연구

이현민,김홍래,윤웅배,김영재,김광기,김석기,유헌,이승훈,신민선,권기철,Lee, Hyun Min,Kim, Hong Rae,Yoon, Woong Bae,Kim, Young Jae,Kim, Kwang Gi,Kim, Seok Ki,Yoo, Heon,Lee, Seung Hoon,Shin, Min Sun,Kwon, Ki Chul 한국광학회 2015 한국광학회지 Vol.26 No.1

본 연구에서는 뇌 종양 수술에서 다수의 광원과 빔 스플리터 모듈을 사용해 종양과 혈관의 형광영상을 동시에 검출하고 획득한 형광영상을 동일한 디스플레이 장치에 표시함으로써 시술자에게 종양과 혈관의 정확한 정보를 실시간으로 제공할 수 있는 현미경 시스템을 제안한다. 5-ALA(5-Aminolevulinic acid) 와 ICG(Indocyanine green) 의 형광영상의 동시 검출을 위해 빔 스플리터(beam-splitter : BS)모듈을 사용하였고 5-ALA는 600nm, ICG는 800nm이상의 파장 대역에서 가장 효율이 뛰어나도록 구성하였다. 빔 스플리터 모듈은 파장 대역에 따라 광학기기의 구조를 변경할 수 있고 필터를 탈, 착 가능한 구조로 설계하여 필요에 따라 빔 스플리터와 필터의 종류를 변경할 수 있으며 5-ALA 및 ICG 이외의 형광염료를 사용한 시술에서 사용할 수 있다. 빔 스플리터 모듈을 통한 형광영상은 5-ALA는 가시광역, ICG는 근적외선 영역을 검출 할 수 있는 CCD 카메라를 장착해 동일한 디스플레이에서 확인할 수 있고 획득한 형광영상은 닮음 변환(similarity transform)을 이용해 원영상과 정합하여 실시간으로 시술자에게 제공하는 시스템을 구현하였다. In this paper, we propose a microscope system for detecting both a tumor and blood vessels in brain tumor surgery as fluorescence images by using multiple light sources and a beam-splitter module. The proposed method displays fluorescent images of the tumor and blood vessels on the same display device and also provides accurate information about them to the operator. To acquire a fluorescence image, we utilized 5-ALA (5-aminolevulinic acid) for the tumor and ICG (Indocyanine green) for blood vessels, and we used a beam-splitter module combined with a microscope for simultaneous detection of both. The beam-splitter module showed the best performance at 600 nm for 5-ALA and above 800 nm for ICG. The beam-splitter is flexible to enable diverse objective setups and designed to mount a filter easily, so beam-splitter and filter can be changed as needed, and other fluorescent dyes besides 5-ALA and ICG are available. The fluorescent images of the tumor and the blood vessels can be displayed on the same monitor through the beam-splitter module with a CCD camera. For ICG, a CCD that can detect the near-infrared region is needed. This system provides the acquired fluorescent image to an operator in real time, matching it to the original image through a similarity transform.

수술현미경용 다중형광 관측 시스템 연구

김홍래,이현민,윤웅배,김영재,김석기,유헌,주재영,김광기,이승훈,Kim, Hong Rae,Lee, Hyun Min,Yoon, Woong Bae,Kim, Young Jae,Kim, Seok Ki,Yoo, Heon,Joo, Jae Young,Kim, Kwang Gi,Lee, Seung-Hoon 대한의용생체공학회 2015 의공학회지 Vol.36 No.1

Indocyanine green(ICG) and 5-aminolevulinic acid(5-ALA) have been widely used to mark blood vessels or tumors. However, fluorescent dye detection systems were designed to use one type of dyes only. In this study, we proposed a detection system capable of detecting Indocyanine green and 5-aminolevulinic acid. Multiple filters and light sources are integrated into a single system. In this study, we performed analysis of fluorescent dyes and configured a detection system. During the analysis, it was found that Indocyanine green and 5-aminolevulinic acid have the maximum intensity at $40{\mu}M$. We designed light source for fluorescent dyes and conducted compatibility test using a commercial surgical microscope. The fluorescent dye detection system was configured based on the experimental results. The developed system successfully detects Indocyanine green and 5-aminolevulinic acid. Therefore, more efficient surgical operations can be achieved using both fluorescent dyes at the same time. We expect that the developed system can increase the survival rate of patients.