모야모야병에서 염기성 섬모 세포 성장 인자의 역할

김동석,최중언,김세혁,양국희,김현숙,Kim, Dong-Seok,Choi, Joong-Uhn,Kim, Se-Hyuk,Yang, Kook-Hee,Kim, Hyeun-Sook 대한신경외과학회 2001 Journal of Korean neurosurgical society Vol.30 No.1

Objectives and Importance : The present study investigated the levels of basic fibroblast growth factor(bFGF) in the CSF of patients with moyamoya disease and its clinical significance. Methods : The levels of bFGF in CSF, taken from 26 hemispheres of 14 moyamoya patients and 20 patients without vascular anomaly(control group), were measured by an enzyme-linked immunosorbent assay. We analyzed the correlation between the level of bFGF and the clinical factors such as age, onset pattern, development of neovascularization, and cerebral circulation. Results : The CSF of moyamoya patients contained a high concentration of bFGF to a significant extent. The bFGF level was apparently elevated in the patients in whom neovascularization from indirect revascularization, such as modified encephalo-duro-arterio-synangiosis(EDAS) was well developed. A linear correlation between the values of bFGF and clinical progression was noted. Conclusions : The elevation of bFGF in moyamoya disease seems to be specific. Clinically, the bFGF level may be considered a useful indicator to predict the efficacy of indirect revascularization.

원발성 중추신경계 임파종의 임상적 특징과 예후인자에 대한 연구

권흠대,허륭,김동석,박용구,최중언,정상섭,Kwon, Heum Dai,Huh, Ryoong,Kim, Dong Seok,Park, Yong Gou,Choi, Joong Uhn,Chung, Sang Sup 대한신경외과학회 2000 Journal of Korean neurosurgical society Vol.29 No.12

Objective : The incidence of primary CNS lymphoma(PCNSL) has been increasing recently. The purpose of this study is to establish of prognostic factors and treatment options for PCNSL. Methods : Thirty-one PCNSL patients were treated in our institute between 1985 and 1997. All patients were histologically confirmed via stereotactic biopsy or open biopsy. The authors retrospectively analyzed clinical characteristics of PCNSL and prognostic factors, including histological cell types, immunohistological cell types and treatment options of PCNSL. Our data were statistically analyzed using Kaplan Meier survival curve and multivariated ANOVA test. Results : The clinical and radiological characteristics of PCNSL were resembled to those of other reports. The most common histological subtype was diffuse large cell type(55.5%). In immunohistolgical study, the incidence of T-cell lymphoma(35.7%) was very higher than that of others. The radiotherapy could prolonged patients' survival(p=0.021). One-year and 3-year survival rate of PCNSL were 66.9% and 45.9%, respectively. One-year survival rate of B cell and T cell lymphoma were 72.7% and 50.0%, respectively. The patients with B-cell lymphoma showed better prognosis than patients with T-cell lymphoma(p=0.049). Conclusion : On the basis of our data, active radiotherapy could prolong patients' survival. the T-cell lymphoma revealed higher incidence than those of other reports and had poor prognosis than that of B cell lymphoma.

수두증 흰쥐 모델에서 수두증 정도에 따른 체성 감각 유발 장전위의 변화

김동석,이광수,박용구,김세혁,최중언,이배환,류재욱,Kim, Dong-Seok,Lee, Kwang-Soo,Park, Yong-Goo,Kim, Se-Hyuk,Choi, Joong-Uhn,Lee, Bae-Hwan,Ryou, Jae-Wook,Zhao, Chun-Zhi 대한신경외과학회 2000 Journal of Korean neurosurgical society Vol.29 No.1

Objective : Somatosensory evoked potential(SSEP) has been known to be a good method for evaluating brain stem function, but it is not sufficient to check the fine changes of cortical functions. A fine change of cortical function can be expressed with somatosensory evoked cortical field potential(SSEFP) rather than general SSEP. To confirm the usefulness of SSEFP for evaluating the cortical function, the authors simultaneously measured SSEFP and the intracranial pressure-volume index(PVI) in kaolin-induced hydrocephalic rats. Method : Hydrocephalus was induced with injection of 0.1ml kaolin-suspended solution into the cisterna magna in 60 Sprague-Dawley rats. The authors measured PVI and SSEFP 1 week after injection of kaolin-suspended solution. To evaluate the severity of induced hydrocephalus, we measured the transverse diameter of the lateral ventricle on the coronal slice of the rat brain 0.40mm posterior to the bregma. Result : The typical wave form of SSEFP in control rats showed a negative-positive complex wave at early latency. In SSEFP of normal rats, N0 is 10.0 msec, N1 15.3 msec, P1 31.2 msec and N1-P1 amplitude $15.4{\mu}V$. As hydrocephalus progressed, the peak latency of N1 and P1 were delayed. In mild hydrocephalus, negative peak waves were split. The N1-P1 amplitude was decreased only in severe hydrocephalus. The changes of the characteristics of SSEFP according to the severity of hydrocephalus were well correlated with the changes of PVI. Shunting normalized the characteristics of SSEFP in relation to ventricular sizes and PVI in hydrocephalic rats. Conclusion : SSEFP may be useful for evaluating the impairment of cortical function in hydrocephalus.

Slit Ventricle Syndrome in Children : Clinical Presentation and Treatment

신범식,양국희,김동석,최중언,Shin, Beom-Sik,Yang, Kook-Hee,Kim, Dong-Seok,Choi, Joong-Uhn The Korean Neurosurgical Society 2001 Journal of Korean neurosurgical society Vol.30 No.2

틈새뇌실증후군은 수두증으로 션트술을 시행받은 환아에서 CT나 MRI소견상 틈새처럼 좁은 뇌실을 가지고 있으면서 간헐적으로 두통, 구토 또는 의식장애등이 동반되는 질환이다. 1986년부터 1996년까지 총 821명의 환자가 수두증으로 션트술을 시행받았다. 이 환자들의 수두증의 원인은 뇌종양(140명), 출혈(62명), 정상압수두증(64명), 뇌수막염(58명), 외상(54명), 선천성(48명), 뇌낭미충증(31명), 그리고 이유를 알 수 없었던 경우가 364명으로 나타났다. 평균 추적 관찰 기간은 68개월이었으며 총 232명에서 재수술을 시행하였으며 1인당 1.28회의 재수술율을 보였다. 이들중 틈새뇌실 증후군은 6예로 0.7%였다. 틈새뇌실증후군 대부분의 환자는 영아기에 수술을 시행받았다. 처음 수술로부터 틈새뇌실증후군이 발생하기까지의 기간은 4~8년으로 평균 6년후 틈새뇌실증후군이 발생하였다. 동위원소 검사상 6예에서 션트의 기능은 모두 정상이었다. 증상이 경미한 2명의 환자에서는 보존적 치료를 시행하였는데 치료후 증상의 호전을 보였다. 이 환자들은 뇌압측정을 시행하지 않았다. 6명중 1명은 뇌압 측정시 높게 나타나 기존과 같은 압력밸브를 이용하여 재수술을 시행하였다. 3명의 환자는 낮은 뇌압을 보여 안티사이펀밸브나 기존보다 높은 압력의 밸브를 이용하여 재수술을 시행하였다. 틈새뇌실증후군의 치료는 첫째, 증후군의 양상을 정확하게 판단하여, 둘째, 증상을 완화시킬 수 있는 방향으로 치료방침을 설정해야 할 것으로 생각되었다. The term slit ventricle syndrome(SVS) refers to an episodic occurrence of headache, vomiting, and possibly some degree of impaired consciousness in shunted hydrocephalic children in whom slit-like ventricles are seen on CT scan or MRI. Authors present 6 cases with SVS who were treated at our institute for last 10 years. From 1986 to 1996, 821 patients underwent shunt surgery for hydrocephalus. The etiology of hydrocephalus included brain tumor(140 patients), post-hemorrhagic(62 patients), idiopathic normotensive hydrocephalus(64 patients), post-meningitic( 58 patients), post-traumatic(54 patients), congenital(48 patients), neurocysticercosis(31 patients), and unknown etiology(364 patients). During the mean follow-up duration of 68 months, 232 shunt revisions were performed by a revision rate of 1.28 per patient. The incidence of SVS was 0.7%(6 patients). Most of them have been operated on in infancy. Time interval from the first operation to the development of slit-ventricle syndrome ranged from 4 to 8 years, the mean was 6 years. Shuntogram showed patent shunt in all patients. Two patients with less severe clinical symptoms improved with conservative treatment. These patients were not measured ICP because of good hospital course. One patient showed high ICP and needed only revision with same pressure valve as previous shunt. Low ICP was noted in 3 patients. Pressure augmentation using an anti-siphon device(ASD) or upgrading valve system were necessary in these patients. The authors stress that determining type of SVS is the first step in treatment planning and that the best treatment is a strategy aimed at resolving the specific type of SVS responsible for the symptoms.

시험관내 배양된 제대혈 모세포에서의 신경항원 발현

하윤,윤도흠,연동수,김현옥,이진주,조용은,최중언,Ha, Yoon,Yoon, Do Heum,Yeon, Dong Su,Kim, Hyun Ok,Lee, Jin Ju,Cho, Yong Eun,Choi, Joong Uhn 대한신경외과학회 2001 Journal of Korean neurosurgical society Vol.30 No.8

Objectives : Cord blood stem cells have been widely used as donor cells for bone marrow transplantation recently. These cells can give rise to a variety of hematopoietic lineages to repopulate the blood. Recent observations reveal that some bone marrow cells and bone marrow stromal cells(MSCs) can grow to become either neurons or glial cells. It is, however, unclear whether or not there exists stems cells which can differentiate into neurons in the blood during the early stages of postnatal life. Methods : Human cord blood stem cells were prepared from human placenta after full term delivery. To induce neuronal differentiation of stem cells, ${\beta}$-mercaptoethanol was treated. To confirm the neuro-glial characteristics of differentiated stem cells, immunocytochemical stain for NeuN, neurofilament, glial fibrillary acidic protein(GFAP), microtubule associated protein2(MAP2) was performed. RT-PCR was performed for detecting nestin mRNA and MAP2 mRNA. Results : We showed in this experiment that neuro-glial markers(NeuN, neurofilament, MAP2, GFAP) were expressed and axon-like cytoplasmic processes are elaborated in the cultured human cord blood stem cells prepared from new born placenta after full term delivery. Nestin mRNA was also detected in fresh cord blood monocytes. Conclusions : These results suggest that human cord blood derived stem cells may be potential sources of neurons in early postnatal life.

항암치료를 받은 수모세포종환아에서 예후인자들이 생존률에 미치는 영향

신경미,최성연,원성철,양창현,유철주,서창옥,최중언,김병수,Shin, Kyung Mi,Choi, Sung Yeon,Won, Sung Chul,Yang, Chang Hyun,Lyu, Chuhl Joo,Suh, Chang Ok,Choi, Joong Uhn,Kim, Byung Soo 대한소아청소년과학회 2003 Clinical and Experimental Pediatrics (CEP) Vol.46 No.2

목 적: 소아에 있어서 중추신경계 종양은 백혈병 다음으로 흔하며 그 중 수모세포종은 소아 뇌종양의 약 15-25%를 차지하는 종양으로, 방사선과 항암제에 예민한 것으로 알려져 있고 치료방법의 발달로 장기 생존율도 많이 향상되었다. 소아의 수모세포종의 생존율에 영향을 미치는 인자로는 진단시의 연령, 병기, 병소의 수술적 적출정도 등이 있다. 이번 연구는 수술 후 항암치료와 방사선 치료를 받은 환아들에서 기존에 생존율에 영향을 미치는 것으로 알려져 있는 인자들에 대한 성적을 조사하여 항암요법 후 이들 예후인자들이 생존율에 어떠한 영향을 미치는지를 알아보고자 하였다. 방 법 : 1985년부터 2001년 9월까지 신촌세브란스병원 소아과 및 신경외과에서 수모세포종으로 진단 받고 치료받은 94명의 환자 중 항암치료를 시행 받은 61명의 환자를 대상으로 의무기록을 후향적으로 조사하였다. 결 과 : 항암제 치료를 받은 환자들의 총 생존율을 보면 3년 무진행 생존율이 $66.5{\pm}6.3%$이고 15년 무진행 생존율이 $60.3{\pm}6.7%$로 나타났다. 진단 당시 3세 이상 및 미만 환아의 무진행 생존율은 각각 $64.5{\pm}7.7%$ 및 $48.2{\pm}12.9%$로 각 군간 생존율의 차이는 통계적인 유의성이 없었다. 진단당시 분류에 의한 저위험군 및 고위험군의 무진행 생존율은 각각 $72.7{\pm}10.5%$ 및 $54.6{\pm}8.3%$로 각 군간 생존율의 차이는 통계적인 유의성이 없었다. 수술적 적출에 의한 생존율의 차이도 완전적출은 $65.8{\pm}11.8%$, 아전적출은 $56.8{\pm}8.2%$로 두 군간 생존율의 차이는 통계적인 유의성이 없었다. 결 론 : 이전에 중요하다고 생각되던 예후인자에 따른 생존율의 차이가 나타나지 않는 이유는 항암제 치료가 전체적인 수모세포종의 생존율을 향상시켰지만, 특히 과거 불량예후인자를 가지고 있던 환자들에서 더욱 생존율의 향상을 가지고 왔기 때문인 것으로 보인다. 또한, 현재 대부분의 환자에서 수술, 방사선치료 그리고 항암제 치료가 이루어지고 있는 현실을 볼 때, 과거 예후를 판정하는데 있어 중요하게 여겨졌던 연령, 병기에 따른 위험군, 종양의 적출정도 등은 오히려 치료방법의 강도를 조절하는데 필요한 인자라 여겨지며, 충분한 종양의 적출과 그 이후 적절한 항암제 및 방사선 치료를 받는 것이 생존율에 영향을 미치는 중요한 인자인 것으로 사료된다. Purpose : Brain tumors are the second most common tumor in childhood, and medulloblastomas comprise 15-25% of brain tumors. The well known prognostic factors are age at diagnosis, stage of disease, and extent of surgical excision. In this study, we analysed the prognostic factors in patients who received chemotherapy after excision. Methods : We reviewed the medical records of 61 patients who received chemotherapy among the 94 patients who were diagnosed and treated between Jan 1985 and Sep 2001 in the Department of Pediatrics and Neurosurgery at Severance Hospital. Results : Among the total survival rate of patients who underwent chemotherapy, the 3-yr progression-free survival rate was $66.5{\pm}6.3%$ and the 15-yr progression-free survival rate was $60.3{\pm}6.7%$. The progression-free survival rate for patients with age at diagnosis over 3 yrs old and under 3 yrs old, was $64.5{\pm}7.7%$ and $48.2{\pm}12.9%$ respectively and there was no statistically significant difference. The survival rate of the high vs low risk group by staging was $72.7{\pm}10.5%$ and $54.6{\pm}8.3%$ respectively, and there was no significant difference. The survival rate of patients with total removal vs subtotal removal was $65.8{\pm}11.8%$ and $56.8{\pm}8.2%$ respectively, showing no statistical difference. Conclusion : The reason there is no difference in survival rate according to the traditional prognostic factors is that chemotherapy has improved not only the total survival rate but also the survival rate in patients with poor traditional prognostic factors. So, sufficient removal of tumor followed by proper chemotherapy and radiotherapy is an important factor which influences the survival rate of medulloblastoma patients.

소아 원발성 뇌종양의 치료 결과 : 단일 기관에서의 장기간 추적 관찰

최성연,원성철,유철주,오승환,양창현,서창옥,최중언,김병수,Choi, Sung-Yeon,Won, Sung-Chul,Lyu, Chuhl-Joo,Oh, Seung-Hwan,Yang, Chang-Hyun,Suh, Chang-Ok,Choi, Joong-Uhn,Kim, Byung-Soo 대한소아청소년과학회 2002 Clinical and Experimental Pediatrics (CEP) Vol.45 No.8

목 적: 뇌종양은 소아에서 가장 흔한 고형암종이다. 이번 연구는 15년간의 임상적 고찰을 통해 나이, 성별, 종양의 위치에 따라 소아 뇌종양을 분류해 보았고, 각각의 총생존율을 조사해 보았으며 또한 일부 질환에서는 항암제 추가여부가 생존율에 미치는 영향에 대해서도 조사해 보았다. 방 법 : 1985년 1월부터 2001년 9월까지 세브란스병원에서 진단받고 치료받은 354명의 소아 뇌종양 환자를 대상으로 임상적 기록에 의거하여 후향조사하였다. 결 과 : 소아 뇌종양의 호발 연령은 5-10세와 10-15세가 큰 차이 없이 모두 높았고 남녀비에서는 남자가 조금 우세하였다. 위치별 빈도는 천막상종양(52%)과 천막하종양(48%)에서 비슷하였으나 천막상종양이 근소하게 많았다. 가장 호발하는 종양의 종류는 수모세포종/원시신경외배엽성종양으로 87례(24.6%)였고 다음으로는 소뇌 성상세포종으로 50례(14.1%)였다. 수모세포종, 소뇌 성상세포종, 대뇌 성상세포종은 10년 생존율이 59.4%, 79.3%, 71%로 비교적 예후가 양호하였다. 뇌간교종과 다형성아교모세포종은 10년 생존율이 12.7%, 13.3%로 예후가 불량하였다. 수모세포종의 고위험군에서는 항암제를 사용한 경우에서 사용하지 않은 경우보다 10년 생존율이 유의하게 높았다(54.5%와 40%, P<0.05). 결 론 : 본 연구는 단일기관의 다수의 환자를 대상으로 15년간의 장기간동안 치료 결과를 추적 관찰하여 기타 문헌과의 비교를 해보았다. 수술기법과 방사선, 항암제의 병합요법으로 뇌종양의 생존율 향상이 보고되고 있는바 본 연구에서도 최근 보고처럼 생존율의 향상을 볼 수 있었다. 특히 고위험군 수모세포종의 경우에서는 추가로 항암제를 사용한 경우 생존율이 높아짐을 볼 수 있었다. Purpose : Brain tumors are the most common solid tumor in children. We retrospectively investigated the clinical characteristics of pediatric brain tumors, such as age, sex, tumor site and survival, as seen in a single institution over the last 15 years. We tried to evaluate the role of chemotherapy on the survival of some brain tumors. Methods : Three hundred fifty four children with primary brain tumor who were treated at Severance Hospital from Jan. 1985 to Sep. 2001 were enrolled. Results : Pediatric brain tumors were found most frequently in 10-15 years of age group(35.3%) and the ratio of male to female was 1.3 : 1. Supratentorial tumors(52%) were more frequent than infratentorial tumors(48%). Medulloblastoma/primitive neuroectodermal tumor(PNET) was the most common type(24.6%), followed by cerebellar astrocytoma(14.1%). Ten year survival rate of medulloblastoma, cerebellar astrocytoma and cerebral astrocytoma were 59.4%, 79.3% and 71%, respectively. The prognosis for brain stem glioma and glioblastoma multiforme were still grim with a 10 year survival rate of 12.7% and 13.3%, respectively. The addition of chemotherapy for high grade medulloblastoma led to an improved 10 year survival rate of 54.5%, compared with 40% without chemotherapy. Conclusion : The combined use of chemotherapy and radiation and surgery improved survival rate of pediatric brain tumors in our study. Chemotherapy for high grade medulloblastoma improved the 10 year survival rate. Further data analysis of the treatment modalities will lead to better comparisons.

임상 : 악성 뇌종양에서 Gliadel® Wafer의 효용성; 예비 보고

심규원 ( Kyu Won Shim ),박영석 ( Young Seok Park ),김정희 ( Jong Hee Chang ),장종희 ( Jung Hee Kim ),최중언 ( Joong Uhn Choi ),김동석 ( Dong Seok Kim ) 대한뇌종양학회 2007 대한뇌종양학회지 Vol.6 No.2

Introduction:Adjuvant systemic chemotherapy increases survival for malignant glioma patients. However, it is unable to effectively cross the blood-brain barrier and have unacceptable systemic toxicities, and the short exposure time of tumor tissue to chemotherapeutic agents. Consequently, many researchers have tried to develop innovative local treatments that bypass the blood-brain barrier and allow for direct treatment in the central nervous system(interstitial chemotherapy). Recently, Gliadel® wafer containing carmustine(BCNU) was approved for the interstitial chemotherapy. We present our initial experience in using interstitial chemotherapy as a strategy to treat malignant brain tumors. Materials and Methods:We analyzed the clinical feature, MRI figures, KPS score, and progression-free survival in 13 malignant brain tumor patients treated with interstitial chemotherapy using Gliadel® wafer from Sep 2004 to Dec 2006. There were 6 glioblastomas, 4 anaplastic astrocytomas, and 3 poorly differentiated carcinomas. Each patient has different treatment histories before and after insertion of Gliadel® wafer. Out of 3 metastatic brain tumors, 2 were recurred after gamma knife surgery. Old patient with huge cystic metastatic tumor refused other kind of chemotherapy. So we inserted Gliadel® wafer after grossly total removal of tumor without any other treatment. Three anaplastic astrocytomas and three glioblastomas recurred after surgery or biopsy, followed by concomitant radiation and Temodal chemotherapy. Three glioblastomas and one anaplastic astrocytoma were treated with interstitial chemotherapy using Gliadel® wafer at the first surgery followed by concomitant radiation and Temodal® chemotherapy. Results:There was not any complication related to interstitial chemotherapy using Gliadel® wafer during follow-up (follow up duration:mean - 10 months, range -3~20 months). Three patients were dead 8, 11 and 12 months after after insertion of Gliadel® wafer(2 anaplastic astrocytomas and 1 glioblastoma). Follow-up MRI of 2 glioblastoma patients revealed tumor regrowth 3 and 19 months after insertion of Gliadel® wafer. The others are alive. The survivals showed the good performance status. Conclusion:This would be the brief preliminary report about the local control of the highly infiltrative brain tumor. Because the local progression or recurrence is still problematic combination of interstitial chemotherapy using Gliadel® wafer and systemic chemotherapy with Temodal® or other anticancer agents could improve patient`s survival without increasing additional systemic toxicity.

Hip Migration after Selective Posterior Rhizotomy in Cerebral Palsy

Byeong-Mun Park(박병문),Jin-Woo Lee(이진우),Hyung-Chan Kim(김형찬),Hui-Wan Park(박희완),Joong-Uhn Choi(최중언),Dong-Suk Kim(김동석),Chang-Il Park(박창일) 대한정형외과학회 1998 대한정형외과학회지 Vol.33 No.6

수모세포종의 방사선치료 후 전두엽하방 재발된 환자에서 원인 분석 및 구제 치료

조재호(Jae Ho Cho),금웅섭(Woong Sub Koom),이창걸(Chang Geol Lee),김경주(Kyoung Ju Kim),심수정(Su Jung Shim),박진호(Jino Bak),정경근(Kyoungkeun Jeong),김태곤(Tae-Gon Kim),김동석(Dong Seok Kim),최중언(Joong-Uhn Choi),서창옥(Chang Ok Su 대한방사선종양학회 2004 Radiation Oncology Journal Vol.22 No.3

목 적: 두개척수조사(Craniospinal irradiation) 후 전두엽 하방에서 재발(Subfrontal recurrence) 한 수모세포종 두 예를 경험하고, 방사선치료 측면에서 재발의 원인을 분석하고자 하였으며, 효과적인 구제 치료 방법을 모색하고자 하였다. 대상 및 방법: 두 예 모두 고위험군(T3bM1, T3bM3) 수모세포종으로 수술, 항암화학제 및 방사선 병합요법을 시행 받았으며, CT-Simulation으로 방사선치료계획이 이루어졌다. 한 예는 방사선치료 후 16개월에 재발하여 구제수술을 시행하고, 세기조절방사선치료로 30.6 Gy의 방사선을 재조사하였다. 다른 한 예는 12개월에 재발하여 구제수술만 시행하였다. 재발인자 확인을 위해 초기 방사선치료 시 사용되었던 모의치료사진을 확인하였고, 안구차폐의 과다 여부 및 가능한 원인 인자의 분석과 재발을 방지하기 위한 대안을 찾고자 하였다. 한예에서 방사선재조사에 대한 부담과 주변 중요정상장기의 인접성 때문에 전두엽하방재발 종양에 대한 구제치료로서 세기조절방사선치료를 계획하였으며, 표적체적에 대해서 7문 조사, 평균선량 30.6 Gy (1.8 Gy 분할, 최대선량의 85%)를 처방하고, 주변 정상중요장기인 시신경은 평균선량을 25 Gy, 안구는 10 Gy로 제한하였다. 결 과: 두 예 모두에서 모의치료사진상 정상장기 보호를 위한 안구차폐과다로 인한 전두엽하방 표적체적 일부에서의 저선량점을 확인할 수 있었다. CT-Simulation 상에서 automatic organ drawing 기능을 이용하여 전뇌와 안구의 외측 경계를 모의치료사진 화면에 같이 올릴 경우 차폐의 적절성을 판단하기가 더 용이하였다. 세기조절방사선치료계획 결과 표적체적에는 평균선량 31.1 Gy, 최대선량 36 Gy, 좌측 및 우측 시신경의 평균선량은 각각 13.9 Gy와 14.7 Gy, 좌우측 안구의 평균선량은 각각 5.5 Gy와 6.9 Gy로 우수한 치료계획을 획득하였다. 구제치료로 수술 및 세기변조방사선치료를 시행한 환자는 이후 방사선치료에 의한 부작용 없이 1년 간 무병상태이다. 결 론: 수모세포종의 전두엽하방 재발을 방지하기 위한 노력으로 두개척수조사 시 전두엽하방 및 체판 부위에 대한 각별한 주의를 기울여 차폐를 실시하여야 하겠고, 일단 재발하여 방사선재조사의 필요가 있는 경우 주변정상장기와의 방사선 선량 차이를 극대화할 수 있는 세기조절방사선치료를 통해 방사선치료 부작용의 부담을 줄일 수 있을 것으로 기대된다. Purpose: Firstly, to analyze factors in terms of radiation treatment that might potentially cause subfrontal relapse in two patients who had been treated by craniospinal irradiation (CSI) for medulloblastoma. Secondly, to explore an effective salvage treatment for these relapses. Materials and Methods: Two patients who had high-risk disease (T3bM1, T3bM3) were treated with combined chemoradiotherapy. CT-simulation based radiation-treatment planning (RTP) was performed. One patient who experienced relapse at 16 months after CSI was treated with salvage surgery followed by a 30.6 Gy IMRT (intensity modulated radiotherapy). The other patient whose tumor relapsed at 12 months after CSI was treated by surgery alone for the recurrence. To investigate factors that might potentially cause subfrontal relapse, we evaluated thoroughly the charts and treatment planning process including portal films, and tried to find out a method to give help for placing blocks appropriately between subfrotal-cribrifrom plate region and both eyes. To salvage subfrontal relapse in a patient, re-irradiation was planned after subtotal tumor removal. We have decided to treat this patient with IMRT because of the proximity of critical normal tissues and large burden of re-irradiation. With seven beam directions, the prescribed mean dose to PTV was 30.6 Gy (1.8 Gy fraction) and the doses to the optic nerves and eyes were limited to 25 Gy and 10 Gy, respectively. Results: Review of radiotherapy portals clearly indicated that the subfrontal-cribriform plate region was excluded from the therapy beam by eye blocks in both cases, resulting in cold spot within the target volume. When the whole brain was rendered in 3-D after organ drawing in each slice, it was easier to judge appropriateness of the blocks in port film. IMRT planning showed excellent dose distributions (Mean doses to PTV, right and left optic nerves, right and left eyes: 31.1 Gy, 14.7 Gy, 13.9 Gy, 6.9 Gy, and 5.5 Gy, respectively. Maximum dose to PTV: 36 Gy). The patient who received IMRT is still alive with no evidence of recurrence and any neurologic complications for 1 year. Conclusion: To prevent recurrence of medulloblastoma in subfrontal-cribriform plate region, we need to pay close attention to the placement of eye blocks during the treatment. Once subfrontal recurrence has happened, IMRT may be a good choice for re-irradiation as a salvage treatment to maximize the differences of dose distributions between the normal tissues and target volume.