종양의 움직임과 호흡주기에 따른 체적 변화에 대한 연구: 팬텀 Study

김민수,백금문,김대섭,강태영,홍동기,권경태,Kim, Min-Su,Back, Geum-Mun,Kim, Dae-Sup,Kang, Tae-Yeong,Hong, Dong-Ki,Kwon, Kyung-Tae 대한방사선치료학회 2010 대한방사선치료학회지 Vol.22 No.2

Purpose: To accurately define internal target volume (ITV) for treatment of moving target considering tumor size and respiratory motion, we quantitatively investigated volume of target volume delineated on CT images from helical CT and 4D CT scans. Materials and Methods: CT images for a 1D moving phantom with diameters of 1.5, 3, and 6 cm, acryl spheres were acquired using a LightSpeed $RT^{16}CT$ simulator. To analyze effect of tumor motion on target delineation, the CT image of the phantoms with various moving distances of 1~4 cm, and respiratory periods of 3~6 seconds, were acquired. For investigating the accuracy of the target trajectory, volume ratio of the target volumes delineated on CT images to expected volumes calculated with diameters of spherical phantom and moving distance were compared. Results: Ratio$_{helical}$ for the diameter of 1, 5, 3, and 6 cm targets were $32{\pm}14%$, $45{\pm}14%$, and $58{\pm}13%$, respectively, in the all cases. As to 4DCT, RatioMIP were $98{\pm}8%$, $97{\pm}5%$, and $95{\pm}1%$, respectively. Conclusion: The target volumes delineated on MIP images well represented the target trajectory, in comparison to those from helical CT. Target volume delineation on MIP images might be reasonable especially for treatment of early stage lung cancer, with meticulous attention to small size target, large respiratory motion, and fast breathing.

전립선암 방사선치료 시 광자극발광선량계를 이용한 광중성자선량 평가

이주아(Joo Ah Lee),백금문(Geum Mun Back),김연수(Yeon Soo Kim),손순룡(Soon Yong Son),최관우(Kwan Woo Choi),유병규(Beong Gyu Yoo),정회원(Hoi Woun Jeong),정재홍(Jae Hong Jung),김기원(Ki Won Kim),민정환(Jung Whan Min) 대한방사선과학회(구 대한방사선기술학회) 2014 방사선기술과학 Vol.37 No.2

본 연구는 전립선암의 방사선치료에 적용되는 치료기법별 세기조절방사선치료의 적절한 조사문수의 선택 및 광중성자 피폭을 고려한 방사선 치료계획 수립을 위한 기초자료를 제공하고자 하였다. 연구대상은 2013년 9월부터 2014년 1월까지 5개월 동안 전립선암으로 방사선치료를 받은 환자 10명을 대상으로 하였다. 그리고 3-dimensional conformal radiotherapy (3D-CRT), volumetric-modulated arc radiotherapy (VMAT), intensity modulated radiation therapy (IMRT) 5, 7, 9 조사문으로 각각 치료계획을 수립하였다. 기술통계와 분산분석으로 광중성자선량의 평균적 차이를 비교하였으며, 상관관계분석과 회귀분석으로 상관성 및 영향을 분석하였다. 연구 결과, 치료기법별로는 3D-CRT가 가장 낮았다. 또한 IMRT가 가장 높게 측정되었으며, 통계적으로 매우 유의하였다 (p<.01). 세기조절방사선치료 조사문수별 광중성자선량은 평균 4.37 ± 1.08 mSv였으며, 조사문수 간에 통계적으로 매우 유의한 차이를 보였다(p<.01). 그리고 조사문수와 광중성자선량은 상관계수가 0.570으로 나타나 통계적으로 매우 유의한 양의 상관관계를 보였다 (p<.01). 조사문수와 광중성자 선량의 선형회귀분석 결과, 조사문수가 1단계 증가할 때마다 평균적으로 광중성자선량이 0.373배로 유의하게 증가하였다. 결론적으로 전립선암의 방사선치료에 빈번히 사용하고 있는 IMRT의 조사문수의 선택 및 광중성자 피폭선량 및 방사선 치료계획의 질적 수준 평가를 고려한 적절한 치료계획 선택에 있어 기초자료로 활용될 수 있으리라 기대된다. This study is to provide basic information regarding photoneutron doses in terms of radiation treatment techniques and the number of portals in intensity-modulated radiation therapy (IMRT) by measuring the photoneutron doses. Subjects of experiment were 10 patients who were diagnosedwithprostate cancer and have received radiation treatment for 5 months from September 2013 to January 2014 in the depart-ment of radiation oncology in S hospital located in Seoul. Thus, radiation treatment plans were created for 3-Dimensional Conformal Radiotherapy (3D-CRT), Volumetric-Modulated Arc Radiotherapy (VMAT), IMRT 5, 7, and 9 portals. The average difference of photoneutron dose was compared through descriptive statistics and variance analysis, and analyzed influence factors through correlation analysis and regression analysis. In summarized results, 3D-CRT showed the lowest average photoneutron dose, while IMRT caused the highest dose with statistically significance (p <.01). The photoneutron dose by number of portals of IMRT was 4.37 ± 1.08 mSv in average and statistically showed very significant difference among the number of portals (p <.01). Number of portals and photoneutron dose are shown that the correlation coefficient is 0.570, highly statistically significant positive correlation (p <.01). As a result of the linear regression analy-sis of number of portals and photoneutron dose, it showed that photoneutron dose significantly increased by 0.373 times in average as the number of portals increased by 1 stage. In conclusion, this study can be expected to be used as a quantitative basic data to select an appropriate IMRT plans regarding photo-neutron dose in radiation treatment for prostate cancer.

전산화단층모의치료기를 이용한 경기관지 근접치료환자의 치료계획에 관한 고찰

서동린,김대섭,백금문,Seo, Dong Rin,Kim, Dae Sup,Back, Geum Mun 대한방사선치료학회 2013 대한방사선치료학회지 Vol.25 No.1

목 적: 경기관지 근접치료에 이용되는 2차원 치료계획의 경우 환부를 확인하는 과정에서 종양의 위치 파악에 어려움이 있어 정확한 치료계획 분석이 어려울 수 있다. 이에 본 연구에서는 전산화단층모의치료기를 이용한 3차원 치료계획으로 환자의 치료계획을 비교 분석하고자 한다. 대상 및 방법: 2012년 6월 본원을 내원한 환자를 대상으로 전산화모의치료장비(Lightspeed RT, GE, USA)와 Oncentra Brachy planning system (Nucletron, Netherland)를 사용하여 3차원 치료계획을 시행하여 2차원 치료계획과 비교 분석하였다. 결 과: 분할 조사로 시행되는 경기관지 근접치료에서 매회 카테터의 위치 파악이 치료계획 상에서 확인 되었고, GTV 용적은 $3.5cm^3$, $3.3cm^3$로 확인 할 수 있었다. 또한 종양의 선량분포 파악이 용이하여 GTV에 대하여 첫 번째 치료 시 처방선량의 92%, 두 번째 치료 시 88%로 파악되어 선량전달 오차를 파악할 수 있었다. 결 론: 2차원 치료계획을 통한 근접치료의 문제점을 보완하기 위하여 치료용적과 선량분포의 정확한 파악과 분석이 가능한 3차원 치료계획으로 검증이 필요하고, 선량전달 오차를 정량적으로 파악하여 치료계획에 반영하는 과정이 필요하다고 생각된다. Purpose: Transbronchial brachytherapy used in the two-dimensional treatment planning difficult to identify the location of the tumor in the affected area to determine the process analysis. In this study, we have done a comparative analysis for the patient's treatment planning using a CT simulator. Materials and Methods: The analysis was performed by the patients who visited the hospital to June 2012. The patient carried out CT-image by CT simulator, and we were plan to compare with a two-dimensional and threedimensional treatment planning using a Oncentra Brachy planning system (Nucletron, Netherland). Results: The location of the catheter was confirmed the each time on a treatment planning for fractionated transbronchial brachytherapy. GTV volumes were $3.5cm^3$ and $3.3cm^3$. Also easy to determine the dose distribution of the tumor, the errors of a dose delivery were confirmed dose distribution of the prescibed dose for GTV. In the first treatment was 92% and the second was 88%. Conclusion: In order to compensate for the problem through a two-dimensional treatment planning, it is necessary to be tested process for the accurate identification and analysis of the treatment volume and dose distribution. Quantitatively determine the dose delivery error process that is reflected to the treatment planning is required.

영상 유도 방사선치료 시 Fiducial Marker의 Artifact에 관한 연구

김종민,김대섭,백금문,강태영,홍동기,윤화룡,권경태,Kim, Jong-Min,Kim, Dae-Sup,Back, Geum-Mun,Kang, Tae-Yeong,Hong, Dong-Ki,Yun, Hwa-Yong,Kwon, Kyeong-Tae 대한방사선치료학회 2010 대한방사선치료학회지 Vol.22 No.1

Purpose: The effect of artifact was analyzed, which occurs from fiducial marker during the liver Image Guided Radiation Therapy (IGRT) using the fiducial marker. Materials and Methods: The size of artifact of fixed fiducial marker and length of mobile fiducial marker locus were measured using the On-Board Imager system (OBI) and CT simulator, and 2D-2D matching and 3D-3D matching were carried out, respectively, and at this time, the coordinates transition value of couch was analyzed. Results: The measurement of fixed fiducial marker artifact size indicated CT 4.90, 8.10, 12.90, 19.70 mm and OBI 5.60, 10.60, 14.70, 29.40 mm based on the reference CT slice thickness of 1.25, 2.50, 5.00, and 10.00 mm. Meanwhile, the measurement of mobile fiducial marker locus length indicated CT 42.00, 43.10, 46.50 mm, and OBI 43.40, 46.00, 49.30 mm. The coordinates transition of 1.00, 2.00, and 8.00 mm occurred between 2D-2D matching and 3D-3D matching. Conclusion: It was confirmed that the therapy error increased during IGRT due to the influence of artifact when CT slice thickness increased. Thus, it may be desirable to acquire the image less than 2.50 mm in slice thickness when IGRT is implemented using the fiducial marker.

광유도발광선량계(Optically Stimulated Luminescent Dosimeter)의 선량 특성에 관한 고찰

김정미,전수동,백금문,조영필,윤화룡,권경태,Kim, Jeong-Mi,Jeon, Su-Dong,Back, Geum-Mun,Jo, Young-Pil,Yun, Hwa-Ryong,Kwon, Kyung-Tae 대한방사선치료학회 2010 대한방사선치료학회지 Vol.22 No.2

Purpose: The purpose of this study was to evaluate dosimetric characteristics of Optically stimulated luminescent dosimeters (OSLD) for dosimetry Materials and Methods: InLight/OSL $NanoDot^{TM}$ dosimeters was used including $Inlight^{TM}MicroStar$ Reader, Solid Water Phantom, and Linear accelerator ($TRYLOGY^{(R)}$) OSLDs were placed at a Dmax in a solid water phantom and were irradiated with 100 cGy of 6 MV X-rays. Most irradiations were carried out using an SSD set up 100 cm, $10{\times}10\;cm^2$ field and 300 MU/min. The time dependence were measured at 10 minute intervals. The dose dependence were measured from 50 cGy to 600 cGy. The energy dependence was measured for nominal photon beam energies of 6, 15 MV and electron beam energies of 4-20 MeV. The dose rate dependence were also measured for dose rates of 100-1,000 MU/min. Finally, the PDD was measured by OSLDs and Ion-chamber. Results: The reproducibility of OSLD according to the Time flow was evaluated within ${\pm}2.5%$. The result of Linearity of OSLD, the dose was increased linearly up to about the 300 cGy and increased supralinearly above the 300 cGy. Energy and dose rate dependence of the response of OSL detectors were evaluated within ${\pm}2%$ and ${\pm}3%$. $PDD_{10}$ and PDD20 which were measured by OSLD was 66.7%, 38.4% and $PDD_{10}$ and $PDD_{20}$ which were measured by Ion-chamber was 66.6%, 38.3% Conclusion: As a result of analyzing characteration of OSLD, OSLD was evaluated within ${\pm}3%$ according to the change of the time, enregy and dose rate. The $PDD_{10}$ and $PDD_{20}$ are measured by OSLD and ion-chamber were evaluated within 0.3%. The OSL response is linear with a dose in the range 50~300 cGy. It was possible to repeat measurement many times and progress of the measurement of reading is easy. So the stability of the system and linear dose response relationship make it a good for dosimetry.

전산화 단층 모의치료기(Computed Tomography Simulator)의 영상을 이용한 TBI(Total Body Irradiation) 자세 잡이 및 보상체 제작의 유용성에 관한 고찰

이우석,박성호,윤인하,백금문,김정만,김대섭,Lee Woo-Suk,Park Seong-Ho,Yun In-Ha,Back Geum-Mun,Kim Jeong-Man,Kim Dae-Sup 대한방사선치료학회 2005 대한방사선치료학회지 Vol.17 No.2

Purpose : We should use a computed tomography-simulator for the body measure and compensator manufacture process was practiced with TBI's positioning in process and to estimate the availability.,Materials and Methods : Patient took position that lied down. and got picture through computed tomography-simulator. This picture transmitted to Somavision and measured about body measure point on the picture. Measurement was done with skin, and used the image to use measure the image about lungs. We decided thickness of compensator through value that was measured by the image. Also, We decided and confirmed position of compensator through image. Finally, We measured dosage with TLD in the treatment department.,Results : About thickness at body measure point. we could find difference of $1{\sim}2$ cm relationship general measure and image measure. General measure and image measure of body length was seen difference of $3{\sim}4$ cm. Also, we could paint first drawing of compensator through the image. The value of dose measurement used TLD on head, neck, axilla, chest(lungs inclusion), knee region were measured by $92{\sim}98%$ and abdomen, pelvis, inquinal region, feet region were measured by $102{\sim}109%$.,Conclusion : It was useful for TBI's positioning to use an image of computed tomography-simulator in the process. There was not that is difference of body thickness measure point, but measure about length was achieved definitely. Like this, manufacture of various compensator that consider body density if use image is available. Positioning of compensator could be done exactly. and produce easily without shape of compensator is courted Positioning in the treatment department could shortened overall $15\{sim}20$ minute time. and reduce compensator manufacture time about 15 minutes.

유방암의 접선조사 시 Field-in-Field Intensity Modulated Radiation Therapy와 Conventional Radiation Therapy의 전산화 치료계획에 관한 고찰

유순미,염미숙,김대섭,백금문,권경태,Yoo, Soon-Mi,Yeom, Mi-Suk,Kim, Dae-Sup,Back, Geum-Mun,Kwon, Kyeong-Tae 대한방사선치료학회 2010 대한방사선치료학회지 Vol.22 No.1

Purpose: To analyze differences in the dose uniformity for the computed breast radiation therapy planning with tangential beam between conventional RT using wedge filter and FiF-IMRT using multileaf collimator based onsizes and volumes of breasts. Materials and Methods: Thirty breast cancer patients were classified according to the sizes and volumes of the breasts using Eclipse treatment planning system ($Varian^{TM}$, USA, V8.0). Conformity Index and Homogeneity Index were computed along with Dose Volume Histogram. Results: No differencein CI (${\pm}1.2%$) was observed. However, lower mean HI (1.67%) in FiF-IMRT was observed compared to that of the conventional RT. Statically significant (P<0.01) correlation was identified between the values of ${\Delta}HI$ (%) and physical parameters such as breast volumes and separations. Conclusion: Increase in breast volume and separation improves the dose uniformities in computed radiation therapy planning for FiF-IMRT. Physical dimension of the breast should be considered to optimize the compured radiation therapy planning.

전신조사방사선치료에서 열형광선량계를 이용한 선량 측정과 체질량지수에 관한 고찰

서동린,김연수,김대섭,윤화룡,백금문,곽정원,Seo, Dong-Rin,Kim, Yeon-Soo,Kim, Dae-Sup,Yoon, Hwa-Ryong,Back, Geum-Mun,Kwak, Jung-Won 대한방사선치료학회 2011 대한방사선치료학회지 Vol.23 No.2

Purpose: The aim of study is to expose a more uniform dose depending on the relationship between a body mass index in patients who underwent radiation therapy and an acquired dosimetric information by using a thermoluminescent dosimeter. Materials and Methods: Since 2006 to August 2011 we investigated 28 people who underwent radiation therapy were enrolled in AMC. Each patient was measured on the head, neck, chest, abdomen, pelvis, thigh, knee joint, and ankle joint using the thermoluminescent dosimeter. The measurement value of each points compared with the prescribed center point, abdominal point, and dose measurements of points on which to base the abdomen and the patient's body mass index (BMI) were compared with reference point, abdomen dose. Results: 28 patients on prescribed dose in the abdomen by which the center point, an average dose was $100.6{\pm}5.5%$, and the other seven measuring points with the average maximum difference among the head, neck, chest, pelvic, thigh, knee, and ankle were $92.8{\pm}4.2%$, $97.6{\pm}6.2%$, $96.4{\pm}5.5%$, $102.6{\pm}5.3%$, $103.4{\pm}7.9%$, $95.8{\pm}5.9%$, $96.1{\pm}5.5%$. The relationship of abdominal point dose and the patient's body mass index (BMI) was analyzed a scatter plot, and the result of linear relationship analysis by regression method, the regression of the dose (y) was -1.009 BMI (x) plus 123.3 and coefficient of determination ($R^2$) was represented 0.697. Conclusion: The total body irradiation treatment process was evaluated the dose deviation and then the prescribed dose by which the average abdominal dose was satisfied with $100.6{\pm}5.5%$. Results of the relationship analysis between BMI and dose, if we apply the correction value for each patients, it can be achieved more uniform dose delivery.

용적변조회전 방사선치료에서 선량전달의 중단 및 재시작에 따른 정확성 평가

이동형,배선명,곽정원,강태영,백금문,Lee, Dong Hyung,Bae, Sun Myung,Kwak, Jung Won,Kang, Tae Young,Back, Geum Mun 대한방사선치료학회 2013 대한방사선치료학회지 Vol.25 No.1

목 적: 용적변조회전 방사선치료는 겐트리 회전과 다엽콜리메이터, 선량률이 연동되어 진행되며 치료 중 선량 전달의 중단이 발생한 경우 겐트리와 다엽콜리메이터가 최초위치부터 다시 동작하여 정지된 지점부터 선량전달이 재개된다. 본 연구는 용적 변조회전 방사선치료의 치료 중단과 재 진행에 따른 선량전달의 오차를 분석하고자 하였다. 대상 및 방법: 10명의 환자를 대상으로 전산화치료계획시스템(Eclipse V10.0, Varian, USA)을 이용하여 용적변조회전 방사선 치료 계획을 수립하였다. TRILOGY (Varian, USA)의 6 MV 선속을 이용하여 계획된 선량을 이차원 배열 검출기와 CUBE (IBA dosimetry, Germany)팬텀에 조사하였다. OmniPro I'mRT system (V1.7b, IBA dosimetry, Germany)을 통해 4회에 걸쳐 일반적인 선량전달의 일관성을 평가 하고 선량 전달의 중단 또는 도어 인터락 발생으로 인해 선량 전달이 중단되고 최초지점부터 다시 시작되어 조사되는 경우와 비교하여 감마지수(Gamma index)의 변화를 분석하였다. 결 과: 선량 전달이 정상적으로 이루어진 경우에 각각의 감마 평균 신호 값의 차이는 0.1로 나타났고, 선량 전달의 중단이 발생한 경우 0.128로 나타났으며 도어 인터락의 경우 0.141로 나타났다. 각각의 경우 감마 표준편차 값의 차이는 0.071, 0.091, 0.099로 나타났고, 감마 최대값의 차이는 0.286, 0.379, 0.413으로 나타났다. Gamma pass rate (3%, 3 mm)는 허용 오차 범위를 만족하였고, T검증 결과 95% 신뢰구간에서 P-value가 0.05 미만으로 유의한 차이를 보였다. 결 론: 본 실험에서 치료 중 선량 전달의 중단 및 재시작에 관한 정확성을 평가해 본 결과 통계적으로는 차이가 있으나 임상적으로 허용 오차 범위이내로 문제가 없다는 것을 알 수 있었다. 그러나 겐트리와 다엽콜리메이터, 선량률의 연동으로 정확성이 요구되는 치료방법인 만큼 선량적인 측면에서 치료 중단에 따른 차이는 간과할 수 없다. 그러므로 갑작스러운 치료 중단 상황이 발생한 경우 추가적인 정도관리 절차를 통해 정확한 선량평가가 이루어져야 할 것으로 사료된다. Purpose: The accurate movement of gantry rotation, collimator and correct application of dose rate are very important to approach the successful performance of Volumetric Modulated Arc Therapy (VMAT), because it is tightly interlocked with a complex treatment plan. The interruption and restart of dose delivery, however, are able to occur on treatment by various factors of a treatment machine and treatment plan. If unexpected problems of a treat machine or a patient interrupt the VMAT, the movement of treatment machine for delivering the remaining dose will be restarted at the start point. In this investigation, We would like to know the effect of interruptions and restart regarding dose delivery at VMAT. Materials and Methods: Treatment plans of 10 patients who had been treated at our center were used to measure and compare the dose distribution of each VMAT after converting to a form of digital image and communications in Medicine (DICOM) with treatment planning system (Eclipse V 10.0, Varian, USA). We selected the 6 MV photon energy of Trilogy (Varian, USA) and used OmniPro I'mRT system (V 1.7b, IBA dosimetry, Germany) to analyze the data that were acquired through this measurement with two types of interruptions four times for each case. The door interlock and the beam-off were used to stop and then to restart the dose delivery of VMAT. The gamma index in OmniPro I'mRT system and T-test in Microsoft Excel 2007 were used to evaluate the result of this investigation. Results: The deviations of average gamma index in cases with door interlock, beam-off and without interruption on VMAT are 0.141, 0.128 and 0.1. The standard deviations of acquired gamma values are 0.099, 0.091, 0.071 and The maximum gamma value in each case is 0.413, 0.379, 0.286, respectively. This analysis has a 95-percent confidence level and the P-value of T-test is under 0.05. Gamma pass rate (3%, 3 mm) is acceptable in all of measurements. Conclusion: As a result, We could make sure that the interruption of this investgation are not enough to seriously affect dose delivery of VMAT by analyzing the measured data. But this investigation did not reflect all cases about interruptions and errors regarding the movement of a gantry rotation, collimator and patient So, We should continuously maintain a treatment machine and program to deliver the accurate dose when we perform the VMAT for the many kinds of cancer patients.

방광암 환자의 영상유도 방사선치료에 관한 고찰

배성수,배선명,김진산,강태영,백금문,권경태,Bae, Seong-Soo,Bae, Sun-Myoung,Kim, Jin-San,Kang, Tae-Young,Back, Geum-Mun,Kwon, Kyung-Tae 대한방사선치료학회 2012 대한방사선치료학회지 Vol.24 No.1

목 적: 현재 본원에서 방광암 환자의 영상유도 방사선치료는 재현성을 높이기 위하여 환자의 상태에 따라 알맞은 양의 생리식염수를 주입하고 영상유도 시스템(On-Board Imager system, OBI, VARIAN, USA)의 Cone.Beam CT (CBCT)로 3차원 정합(3D-3D matching)을 하여 치료를 한다. 본 연구에서는 방광암 환자의 치료 시 획득한 CBCT 영상의 분석을 통해 뼈를 기준으로 한 정합과 방광을 기준으로 한 정합의 차이를 알아보고, 생리 식염수를 주입한 방광의 체적 변화를 알아보고 방광암 환자의 치료 시 더욱 적절한 영상정합방법을 평가하고 고찰하고자 한다. 대상 및 방법: 본원에서 2009년 1월에서 2010년 4월까지 방사선치료를 위해 내원한 방광암 환자 7명을 대상으로 Folly catheter를 이용하여 방광 내 잔류 소변을 제거한 뒤 환자 개개인에 맞게 정해진 양 만큼의 생리식염수를 주입하고 CT-Sim 후 치료계획을 설계하였다. 그 뒤 OBI system을 이용하여 치료 전 자세 확인을 위해 CBCT를 찍었고, 담당 주치의가 모든 대상 환자의 영상 정합을 진행하였다. 총 45개 CBCT 영상을 이용하여 뼈를 기준으로 한 영상정합과 방광을 기준으로 한 영상정합의 차이를 분석하였다. 또, 방광의 체적 변화를 Eclipse (version 8.0, VARIAN, USA)를 통해 얻어냈다. 결 과: 뼈를 기준으로 한 영상정합을 한 후 다시 방광을 기준으로 한 정합의 차이는 X축으로 평균 $3{\pm}2mm$, Y축으로 $1.8{\pm}1.3mm$, Z축으로 $2.3{\pm}1.7mm$이고 전체 이동거리는 $4.8{\pm}2.0mm$로 나타났다. 또 방광의 체적은 기준 대비 $4.03{\pm}3.97%$의 차이를 나타냈다. 결 론: 방광의 특성상 해부학적 위치 및 내부의 움직임으로 인해 뼈를 이용한 영상정합 후에도 방광의 위치 차이가 발생하였다. 또, 생리식염수를 채운 방광의 체적은 4.03%의 차이를 나타냈으나 영상 정합 시 모두 계획한 볼륨 안에 포함되는 것을 확인 할 수 있었다. 따라서 생리식염수를 주입한 뒤 방광을 기준으로 영상 정합을 실시함으로써 더욱 정확한 치료를 실시 할 수 있을 것으로 사료된다. Purpose: In hospital image-guided radiation therapy in patients with bladder cancer to enhance the reproducibility of the appropriate amount, depending on the patient's condition, and image-guided injection of saline system (On-Board Imager system, OBI, VARIAN, USA) three of the Cone-Beam CT dimensional matching (3D-3D matching) to be the treatment. In this study, the treatment of patients with bladder cancer at Cone-Beam CT image obtained through the analysis of the bones based matching and matching based on the bladder to learn about the differences, the bladder's volume change injected saline solution by looking at the bladder for the treatment of patients with a more appropriate image matching is to assess how the discussion. Materials and Methods: At our hospital from January 2009 to April 2010 admitted for radiation therapy patients, 7 patients with bladder cancer using a Folly catheter of residual urine in the bladder after removing the amount determined according to individual patient enough to inject saline CT-Sim was designed after the treatment plan. After that, using OBI before treatment to confirm position with Cone-Beam CT scan was physician in charge of matching was performed in all patients. CBCT images using a total of 45 bones, bladder, based on image matching and image matching based on the difference were analyzed. In addition, changes in bladder volume of Eclipse (version 8.0, VARIAN, USA) persuaded through. Results: Bones, one based image matching based on the bladder and re-matching the X axis is the difference between the average $3{\pm}2mm$, Y axis, $1.8{\pm}1.3mm$, Z-axis travel distance is $2.3{\pm}1.7mm$ and the overall $4.8{\pm}2.0mm$, respectively. The volume of the bladder compared to the baseline showed a difference of $4.03{\pm}3.97%$. Conclusion: Anatomical location and nature of the bladder due to internal movement of the bones, even after matching with the image of the bladder occurred in different locations. In addition, the volume of saline-filled bladder showed up the difference between the 4.03 percent, but matched in both images to be included in the planned volumes were able to confirm. Thus, after injection of saline into the bladder base by providing a more accurate image matching will be able to conduct therapy.