• Radiation Oncology Journal
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• v.21 no.1
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• pp.100-106
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• 2003

Purpose : To develop a patients' setup verification tool (PSVT) to verify the alignment of the machine and the target isocenters, and the reproduclbility of patients' setup for three dimensional conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT). The utilization of this system is evaluated through phantom and patient case studies. Materials and methods : We developed and clinically tested a new method for patients' setup verification, using digitally reconstructed radiography (DRR), simulation, porial and digital images. The PSVT system was networked to a Pentium PC for the transmission of the acquired images to the PC for analysis. To verify the alignment of the machine and target isocenters, orthogonal pairs of simulation images were used as verification images. Errors in the isocenter alignment were measured by comparing the verification images with DRR of CT Images. Orthogonal films were taken of all the patients once a week. These verification films were compared with the DRR were used for the treatment setup. By performing this procedure every treatment, using humanoid phantom and patient cases, the errors of localization can be analyzed, with adjustments made from the translation. The reproducibility of the patients' setup was verified using portal and digital images. Results : The PSVT system was developed to verify the alignment of the machine and the target isocenters, and the reproducibility of the patients' setup for 3DCRT and IMRT. The results show that the localization errors are 0.8$\pm$0.2 mm (AP) and 1.0$\pm$0.3 mm (Lateral) in the cases relating to the brain and 1.1$\pm$0.5 mm (AP) and 1.0$\pm$0.6 mm (Lateral) in the cases relating to the pelvis. The reproducibility of the patients' setup was verified by visualization, using real-time image acquisition, leading to the practical utilization of our software Conclusions : A PSVT system was developed for the verification of the alignment between machine and the target isocenters, and the reproduclbility of the patients' setup in 3DCRT and IMRT. With adjustment of the completed GUI-based algorithm, and a good quality DRR image, our software may be used for clinical applications.

• Proceedings of the KAIS Fall Conference
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• 2009.05a
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• pp.119-122
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• 2009

본 연구는 뇌졸중으로 인한 편마비 환자 20명을 대상으로 총 8주간 시지각 운동 과제를 적용하여 자세 균형, 보행 양상에 미치는 효과를 검증하고자 시행하였다. 실험군(n=10)과 대조군(n=10) 모두 보존적인 물리치료를 실시하였고 실험군에는 시지각 운동 과제 프로그램을 더하여 실시하였다. 본 연구의 결과는 실험군의 되먹임 측정을 통한 자세 균형 검사에서 편평한 지면 위에서 눈을 뜨고 감은 상태의 안정성 지수는 유의한 감소를 보였으며, pillow 위에서 눈을 뜨고 감은 상태의 안정성 지수도 유의하게 감소하였다. 체중분포지수는 편평한 지면에서 눈을 뜨고, 감은 상태와 pillow 위에서 눈을 뜨고 감은 상태 모두에서 유의하게 감소하였다. 실험군에서 10m 보행 속도는 대조군과 달리 유의하게 증가하였다. 본 연구에서의 시지각적 운동과제 프로그램은 편마비 환자의 신체기능과 관련된 자세균형 및 보행을 증진시키는 효과가 있었고 이에 보다 효과적인 운동방법으로 제시할 수 있다.

• The Journal of Korean Society for Radiation Therapy
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• v.27 no.2
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• pp.175-181
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• 2015

Purpose : To evaluate Contralateral Breast Doses with Supine and Prone Positions for tangential Irradiation techniques for left-sided breast Cancer Materials and Methods : We performed measurements for contralateral doses using Human Phantom at each other three plans (conventional technique, Field-in-Field, IMRT, with prescription of 50 Gy/25fx). For the measurement of contralateral doses we used Glass dosimeters on the 4 points of Human Phantom surface (0 mm, 10 mm, 30 mm, 50 mm). For the position check at every measurements, we had taken portal images using EPID and denoted the incident points on the human phantom for checking the constancy of incident points. Results : The contralateral doses in supine position showed a little higher doses than those in prone position. In the planning study, contralateral doses in the prone position increased mean doses of 1.2% to 1.8% at each positions while those in the supine positions showed mean dose decreases of 0.8% to 0.9%. The measurements using glass dosimeters resulted in dose increases (mean: 2.7%, maximum: 4% of the prescribed dose) in the prone position. In addition, the delivery techniques of Field-in-field and IMRT showed mean doses of 3% higher than conventional technique. Conclusion : We evaluated contralateral breast doses depending on different positions of supine and prone for tangential irradiations. For the phantom simulation of set-up variation effects on contralateral dose evaluation, although we used humanoid phantom for planning and measurements comparisons, it would be more or less worse set-up constancy in a real patient. Therefore, more careful selection of determination of patient set-up for the breast tangential irradiation, especially in the left-sided breast, should be considered for unwanted dose increases to left lung and heart. In conclusion, intensive patient monitoring and improved patient set-up verification efforts should be necessary for the application of prone position for tangential irradiation of left-sided breast cancer.

• Proceedings of the KOSOMBE Conference
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• v.1995 no.11
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• pp.63-67
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• 1995

신체 자세균형의 안정도를 반영하는 압력중심(COP)을 계측하기 위해 정삼각형 모양의 평형판 시스템을 설계, 제작하였고 그 유용성을 평가하였다. 재질로는 강도와 가공성이 뛰어난 듀랄루민을 사용하였고 압력중심(COP)의 위치를 계측하는 힘센 서로는 공업용 로드셀 3개를 사용하였다. COP신호를 검출하는 전자회로를 제작하여 실험한 결과 평형판의 COP 위치측정 오차는 2% 미만이었다. 시스템의 임상응용가능성을 평가하기 위하여 정상인 10명과 이학적 평가가 정상인 환자 4명을 대상으로 임상실험을 수행하였다. 자세안정도를 반영할 척도로써 COP신호의 표준편차($SD_x,\;SD_y,\;SD_r$)를 설정하여 자세가 불안정해짐에 따라, 그리고 시각의 영향이 배제됨에 따라 이 값들이 증가하는 것을 관찰하였다. 또한 환자의 경우에는 정상인과 현저한 차이를 보였다. 즉, 본 평형판시스템이 자세안정도를 정량적이고 예민하게 계측할 수 있음을 확인하였고 임상적 실용성을 검증하였다.

• The Journal of Korean Society for Radiation Therapy
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• v.21 no.2
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• pp.83-88
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• 2009

Purpose: Cone beam computed tomography (CBCT) using an on board imager (OBI) can check the movement and setup error in patient position and target volume by comparing with the image of computer simulation treatment in real.time during patient treatment. Thus, this study purposed to check the change and movement of patient position and target volume using CBCT in IMRT and calculate difference from the treatment plan, and then to correct the position using an automated match system and to test the accuracy of position correction using an electronic portal imaging device (EPID) and examine the usefulness of CBCT in IMRT and the accuracy of the automatic match system. Materials and Methods: The subjects of this study were 3 head and neck patients and 1 pelvis patient sampled from IMRT patients treated in our hospital. In order to investigate the movement of treatment position and resultant displacement of irradiated volume, we took CBCT using OBI mounted on the linear accelerator. Before each IMRT treatment, we took CBCT and checked difference from the treatment plan by coordinate by comparing it with the image of CT simulation. Then, we made correction through the automatic match system of 3D/3D match to match the treatment plan, and verified and evaluated using electronic portal imaging device. Results: When CBCT was compared with the image of CT simulation before treatment, the average difference by coordinate in the head and neck was 0.99 mm vertically, 1.14 mm longitudinally, 4.91 mm laterally, and 1.07o in the rotational direction, showing somewhat insignificant differences by part. In testing after correction, when the image from the electronic portal imaging device was compared with DRR image, it was found that correction had been made accurately with error less than 0.5 mm. Conclusion: By comparing a CBCT image before treatment with a 3D image reconstructed into a volume instead of a 2D image for the patient's setup error and change in the position of the organs and the target, we could measure and correct the change of position and target volume and treat more accurately, and could calculate and compare the errors. The results of this study show that CBCT was useful to deliver accurate treatment according to the treatment plan and to increase the reproducibility of repeated treatment, and satisfactory results were obtained. Accuracy enhanced through CBCT is highly required in IMRT, in which the shape of the target volume is complex and the change of dose distribution is radical. In addition, further research is required on the criteria for match focus by treatment site and treatment purpose.

• Physical Therapy Korea
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• v.10 no.4
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• pp.85-94
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• 2003

본 연구에서는 근골격계 통증이 자세유지와 균형능력에 핵심이 되는 중력중심 이동에 미치는 영향에 대해 알아봄으로서, 균형과 자세에 영향을 주는 다양한 요소들에 대한 새로운 접근을 시도해 보고자 한다. I-병원의 입원 및 외래 환자 중 신경계 손상이 없고 중력중심 이동에 직접적인 영향을 줄 수 있는 하지에 정형외과적 장애가 없으며, 전정계 손상이나 시력장애로 인한 균형에 문제가 없이 근골격계 질환으로 요통과 견통을 주소로 하는 71명의 환자(남자 38, 여자 33; 평균연령=44, 표준편차=13.8, 범위=19~79)와 신경계, 근골격계 및 평형감각에 문제가 없는 정상인 30명의 대조군(남자 16, 여자 14; 평균연령=39.2, 표준편차=13.7, 범위=21~72)을 대상으로 전산화된 힘판을 이용하여 중력중심 이동의 궤적을 표준편차값으로 측정하였다. 측정된 중력중심 이동값은 두 군간에 상이한 차이를 보이고 있음이 검증되었다(p<.01). 또 측정된 여러 변수들의 중력중심 이동에 대한 영향력을 알아보기 위해 나이, 체중 및 신장과 중력중심 이동과의 상관분석 결과 중력중심 이동의 15.8%를 체중의 변화에 의한 것으로 설명할 수 있다는 결과를 얻었으며, 그 외의 변수들과의 연관성에 대해선 유의미한 차이가 없었다(p<.01). 결과적으로 근골격계 통증은 올바른 자세유지와 균형유지를 위한 감각통합과 반응과정에 직접, 간접적으로 영향을 미치고 있다. 따라서 중력 중심 이동이 크면 클수록 중심을 잡기 위한 근육활동으로 추가적인 에너지가 사용되고, 편중된 중력중심 이동은 근골격계에 무리한 부담을 주어 통증을 증가시킬 수 있을 것이다. 또 통증으로 인한 중력중심 이동은 이를 보상하기 위해 신체 먼 곳에서의 이차적인 변형을 초래하여 각종 근골격계 증상의 원인이 될 수 있으므로 근골격계에 대한 적절한 치료는 통증을 감소시켜 자세의 이차적인 변형을 막고 자세유지 시 작용하는 근육의 에너지 효율을 높일 수 있을 것으로 사료된다.

• Radiation Oncology Journal
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• v.20 no.2
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• pp.165-171
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• 2002

Purpose : In order to perform craniospinal irradiation (CSI) in the supine position on patients who are unable to lie in the prone position, a new simulation technique using a CT simulator was developed and its availability was evaluated. Materials and Method : A CT simulator and a 3-D conformal treatment planning system were used to develop CSI in the supine position. The head and neck were immobilized with a thermoplastic mask in the supine position and the entire body was immobilized with a Vac-Loc. A volumetrie image was then obtained using the CT simulator. In order to improve the reproducibility of the patients' setup, datum lines and points were marked on the head and the body. Virtual fluoroscopy was peformed with the removal of visual obstacles such as the treatment table or the immobilization devices. After the virtual simulation, the treatment isocenters of each field were marked on the body and the immobilization devices at the conventional simulation room. Each treatment field was confirmed by comparing the fluoroscopy images with the digitally reconstructed radiography (DRR)/digitally composite radiography (DCR) images from the virtual simulation. The port verification films from the first treatment were also compared with the DRR/DCR images for a geometrical verification. Results : CSI in the supine position was successfully peformed in 9 patients. It required less than 20 minutes to construct the immobilization device and to obtain the whole body volumetric images. This made it possible to not only reduce the patients' inconvenience, but also to eliminate the position change variables during the long conventional simulation process. In addition, by obtaining the CT volumetric image, critical organs, such as the eyeballs and spinal cord, were better defined, and the accuracy of the port designs and shielding was improved. The differences between the DRRs and the portal films were less than 3 mm in the vertebral contour. Conclusion : CSI in the supine position is feasible in patients who cannot lie on prone position, such as pediatric patienta under the age of 4 years, patients with a poor general condition, or patients with a tracheostomy.

• Progress in Medical Physics
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• v.24 no.2
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• pp.85-91
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• 2013

At present, megavoltage computed tomography (MVCT) is the only method used to correct the position of tomotherapy patients. MVCT produces extra radiation, in addition to the radiation used for treatment, and repositioning also takes up much of the total treatment time. To address these issues, we suggest the use of a video image-guided setup (VIGS) system for correcting the position of tomotherapy patients. We developed an in-house program to correct the exact position of patients using two orthogonal images obtained from two video cameras installed at $90^{\circ}$ and fastened inside the tomotherapy gantry. The system is programmed to make automatic registration possible with the use of edge detection of the user-defined region of interest (ROI). A head-and-neck patient is then simulated using a humanoid phantom. After taking the computed tomography (CT) image, tomotherapy planning is performed. To mimic a clinical treatment course, we used an immobilization device to position the phantom on the tomotherapy couch and, using MVCT, corrected its position to match the one captured when the treatment was planned. Video images of the corrected position were used as reference images for the VIGS system. First, the position was repeatedly corrected 10 times using MVCT, and based on the saved reference video image, the patient position was then corrected 10 times using the VIGS method. Thereafter, the results of the two correction methods were compared. The results demonstrated that patient positioning using a video-imaging method ($41.7{\pm}11.2$ seconds) significantly reduces the overall time of the MVCT method ($420{\pm}6$ seconds) (p<0.05). However, there was no meaningful difference in accuracy between the two methods (x=0.11 mm, y=0.27 mm, z=0.58 mm, p>0.05). Because VIGS provides a more accurate result and reduces the required time, compared with the MVCT method, it is expected to manage the overall tomotherapy treatment process more efficiently.

• Journal of Korean Physical Therapy Science
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• v.7 no.2
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• pp.427-437
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• 2000

편마비 환자의 물리치료는 장애 결과를 완화시키는 것에 초점을 두고 있다. 본 연구는 신경생리학적 개념을 기초로 한 중재 접근 방법 중 편마비 환자에게 신경 발달 치료와 신경근 균형 접근 기법의 중재 효과를 비교 하였다. 연구 대상은 서울특별시와 전라북도에 소재한 종합병원 및 정형외과 의원에 입원 및 통원하고 있는 47-71세의 연령 범위에 있는 편마비 환자 30명 이다. 중재 집단의 기능적 능력 향상을 평가하기 위해 편마비 환자를 위한 운동 평가 척도와 수정된 바델 척도를 평가도구로 사용하였다. 편마비 환자의 기능적 능력 향성을 평가도구에 의해 측정된 결과를 분석한 바 운동평가 척도 항목중 바로누운 자세에서 옆으로 눕기와 앉아서 균형 취하기 영역에서, 수정된 바델 척도 항목 중 식사하기 영역에서 통계적으로 유의한 차이를 보였다(P<.05). 편마비 환자의 손상 부위, 손상 형태, 마비 부위 등의 손상의 본질에 따른 대상의 선정과 운동 조절 형태에 관한 지식 그리고 신경학적 결함 정도를 심도있게 다루어 기능적 능력 향상의 임상적 효과를 검증하는 것이 중요하다.

• The Journal of Korean Society for Radiation Therapy
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• v.29 no.1
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• pp.69-76
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• 2017

Purpose: The purpose of this study was to verify dosimetric results and reproducibility of position during craniospinal irradiation (CSI) using tomotherapy (Accuray Incorporated, USA). Also, by comparing with conventional CSI Technique, we confirmed the efficiency of using a Tomotherapy. Materials and Methods: 10 CSI patients who get tomotherapy participate. Patient-specific quality assurances (QA) for each patient are conducted before treatment. When treating, we took Megavoltage Computed Tomography (MVCT) that range of head and neck before treatment, L spine area after treatment. Also we conducted in-vivo dosimetry to check a scalp dose. Finally, we made a 3D conventional radiation therapy(3D-CRT) of those patients to compare dosimetric differences with tomotherapy treatment planning. Results: V107, V95 of brain is 0 %, 97.2 % in tomotherapy, and 0.3 %, 95.1 % in 3D-CRT. In spine, value of V107, V95 is 0.2 %, 18.6 % in tomotherapy and 89.6 %, 69.9 % in 3D-CRT. Except kidney and lung, tomotherapy reduced normal organ doses than 3D-CRT. The maximum positioning error value of X, Y, Z was 10.2 mm, -8.9 mm, -11.9 mm. Through in-vivo dosimetry, the average of scalp dose was 67.8 % of prescription dose. All patient-specific QA were passed by tolerance value. Conclusion: CSI using tomotherapy had a risk of parallel organ such as lung and kidney because of integral dose in low dose area. However, it demonstrated dosimetric superiority at a target and saved normal organ to reduce high dose. Also results of reproducibility were not exceeded margins that estimated treatment planning and invivo dosimetry showed to reduce scalp dose. Therefore, CSI using tomotherapy is considered to efficient method to make up for 3D-CRT.