방사선조사에서 나노 입자 혼합물의 영향

예지원 영남대학교 의과대학 2011 Yeungnam University Journal of Medicine Vol.28 No.2

Background:To evaluate the changes in the radiation dose and temperature distribution on irradiated egg albumin and nanoparticle (Fe3O4) powder mixed egg albumin. Methods:A new type of phantom was designed by fabricating a 30×30×30cm acryl square inside a 3×3×3cm small square and dividing it into two parts. In the control group, only egg albumin was irradiated, and in the test group, 25nm 20mg/cc, 25nm 40mg/cc, and 1 um 40 mg/cc nanoparticles with egg albumin were irradiated. The radiation isodose distributions and temperature changes were then observed. Results:No significant changes were observed in the radiation dose and temperature distribution. Conclusion:The nanoparticles were considered not to have had any effect on the radiation dose and temperature distribution under the experimental conditions. Further studies can be conducted based on the changes in the mixture material.

Postoperative Complications after Preoperative Chemoradiotherapy Combined with Hyperthermia in Locally Advanced Rectal Cancer

예지원,Yea, Ji Woon Korean Society of Medical Physics 2014 의학물리 Vol.25 No.2

국소 진행성 직장암 환자에서 수술 전 항암방사선동시요법으로 치료시 추가적인 고주파 온열치료 유무가 수술 후 부작용에 미치는 영향을 분석하였다. 1996년부터 2007년 사이, 본원에서 수술 전 항암방사선동시요법과 근치적 수술을 시행한 환자 205명을 대상으로 급, 만성부작용을 분석하였다. 총 방사선치료선량은 39.6 Gy에서 45 Gy였고 1회 내지 2회의 항암약물치료(5-fluorouracil, leucovorin)를 동시에 시행하였다. 88명의 환자가 주 2회, 8-MHz 고주파 온열치료기를 이용한 국소 온열치료를 시행하였다. 외과적 수술은 수술 전 치료 완결 후 4~6주 경과하여 시행하였다. 환자군의 나이 중앙값은 59세(18세~83세)이고 추적관찰기간 중앙값은 61개월(2개월~191개월)이었다. 전체 환자에서 5년 전체생존율과 무합병증 생존율은 77.4%와 73.7%였다. 각각의 조기 누출, 지연 누출, 연결부 협착, 누공, 소장폐쇄의 발생빈도는 1.0%, 2.9%, 1.5%, 5.9%, 그리고 17.1%였다. 온열치료는 모든 종류의 부작용을 증가시키지 않았다. 온열치료를 실시하지 않은 군과 온열치료군 간의 5년 무합병증 생존율은 71.8%와 76.3%였다(p=0.293). 온열치료는 수술전 항암방사선동시요법 후 근치적 수술을 시행하는 국소 진행 직장암 환자의 수술후 부작용을 증가시키지 않는다. We investigated whether regional hyperthermia (HT) increased post-surgical complications in patients with locally advanced rectal cancer treated with preoperative concurrent chemoradiotherapy (CCRT). Between 1996 and 2007, 205 patients treated with preoperative CCRT and curative surgery were evaluable for the analysis of acute and late toxicities. A total dose of 39.6 Gy or 45 Gy was delivered concurrently with one or two cycles of chemotherapy (5-fluorouracil, leucovorin). Eighty-eight patients received regional HT twice a week using an 8-MHz radiofrequency capacitive heating device. Surgery was performed 4~6 weeks after the completion of preoperative CCRT. The median age was 59 years (range, 18~83) and the median follow-up period was 61months (range, 2~191). The 5-year overall survival and complication-free survival rate of all patients was 77.4% and 73.7%, respectively. Early leakage, delayed leakage, anastomotic stricture, fistula, and small bowel obstruction occurred in 1.0%, 2.9%, 1.5%, 5.9%, and 17.1%, respectively. HT did not increase all kinds of complications. The 5-year complication-free survival rate was 71.8% in the non-HT group and 76.3% in the HT group (p=0.293). Regional HT did not increase postoperative complications in patients with locally advanced rectal cancer treated with preoperative CCRT followed by curative surgery.

원발성 폐암에서 정위적 체부 방사선치료의 빔 배열에 따른 선량분포의 비교

예지원,Yea, Ji Woon 한국의학물리학회 2014 의학물리 Vol.25 No.2

원발성 폐암의 정위적 체부 방사선치료(Stereotatic Body Radiation Therapy; SBRT)시에, 종양주위의 빔 배열을 균등하게 한 $360^{\circ}$회전각도(Equally angles; EA)와 종양주위의 빔 배열을 부분각도(Partially angles; PA)로 배열한 치료계획의 선량차이를 확인하기 위하여, 세기조절방사선치료(Intensity-modulated radiation therapy, IMRT)와 체적변조회전치료(Volumetric-modulated arc therapy, VMAT)의 종양의 선량, 동측 폐의 선량, 반대측 폐의 선량, 손상위험장기(Organ at risk, OAR)의 선량, 치료효율 등을 비교분석 하였다. 12명의 환자에서 각각 4종류($IMRT_{EA}$, $IMRT_{PA}$, $VMAT_{EA}$, $VMAT_{PA}$)의 치료계획을 생성하였으며, 처방선량은 총 선량 60 Gy, 4회 분할치료로 표적체적 95%에 대해 100% 선량이 포함되게 하였다. IMRT와 VMAT의 치료계획 평가에서 $360^{\circ}$회전각도의 빔 균등배열과 부분각도 빔 배열에서 변수중 선량일치지수, 균질성지수, 고선량 유출, $D_{2cm}$, $R_{50}$은 빔 배열에 따라 크게 차이가 나지 않았다. 또한 손상위험장기인 척수, 기관지, 식도의 최고선량은 각각의 방법에 따라 차이를 나타내었다. 특히 $HDS_{location}$에서 21.63%와 26.46%의 큰 차이를 나타내었다. To compare 2 beam arrangements, circumferential equally angles (EA) beams or partially angles (PA) beams for stereotactic body radiation therapy (SBRT) of primary lung cancer for intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) delivery techniques with respect to target, ipsilateral lung, contralateral lung, and organs-at-risk (OAR) dose-volume metrics, as well as treatment delivery efficiency. Data from 12 patients, four treatment plans were generated per data sets ($IMRT_{EA}$, $IMRT_{PA}$, $VMAT_{EA}$, $VMAT_{PA}$). The prescribed dose (PD) was 60 Gy in 4 fractions to 95% of the planning target volume (PTV) for a 6-MV photon beam. When compared with the IMRT and VMAT treatment plan for 2 beams, conformity index, homogeneity index, high dose spillage, D2 cm (Dmax at a distance ${\geq}2cm$ beyond the PTV), R50 (ratio of volume circumscribed by the 50% isodose line and the PTV), resulted in similar. But Dmax of the Organ at risk (OAR), spinal cord, trachea, resulted in differ between four treatment plans. Especially $HDS_{location}$ showed big difference in 21.63% vs. 26.46%.

처방전달 시스템을 이용한 방사선종양학과 진료업무의 전산화

신세원,예지원 영남대학교 의과대학 1996 Yeungnam University Journal of Medicine Vol.13 No.1

현대는 정보화의 사회로서 첨단과학을 이용한 진료업무의 선진화작업은 진료의 서비스 향상과 경영혁신을 위해 필수적이다. 이번에 새로이 개발된 방사선종양학과 진료업무 전산화 시스템 개발과정에서 별도의 비용부담없이 부수적으로 개발된 것으로 방사선 종양학과의 고유 업무 뿐만 아니라 모든 외래 및 병실진료업무와 수납업무를 수행 할 수 있는 편리한 프로그램이다. 이 시스템의 도입으로 방사선종양학과의 진료업무 간소화는 물론 신속 정확한 진료가 가능하여 진료서비스를 향상시켜 향후 다가올 진료 환경의 급격한 변화에 적극적으로 대처할 수 있어서 진료업무의 능률향상에 큰 도움이 되며 몇가지의 새로운 기능을 추가시키면 학문연구의 발전과 경영개선효과도 기대할 수 있으리라 생각된다. Recently there has been attempts to develop hospital information system including order communicating system, patient tracing system, tumor registry system, office automation system and picture archiving and communication system(PACS). The authors developed a practical system that was operated via order communication system of Yeungnam University Hospital. The system provided us the speed, accuracy, reliability, retention, economy and wide applicability through practical test. So we believed that this system would be one of standard computerized programs in radiation oncology practice and providing widely usable data for clinical statistics, medical record, tumor registry system and clinical researches.

경도지적장애 학생의 이야기 쓰기 분석

예지원 ( Ye Ji-won ),김화수 ( Kim Wha-soo ),이근용 ( Rhee Kun-yong ) 대구대학교 특수교육재활과학연구소 2017 특수교육재활과학연구 Vol.56 No.2

본 연구는 경도지적장애 학생의 이야기 쓰기의 특성을 알아보기 위하여 말없는 단편 애니메이션을 활용하여 언어연령을 일치시킨 일반학생과 비교하였다. 이야기 쓰기의 특성으로 이야기 문법, 전체 단어 수, 구문 복잡성, 어휘다양도, 정확도(철자오류, 비문사용)를 분석하였다. 연구의 대상은 경도지적장애 학생 중 다른 중복장애가 없으며 쓰기에 문제가 없고, 언어연령이 9-11세인 학생으로 하였다. 연구 결과, 경도지적장애 학생은 이야기 문법, 전체단어 수, 어휘다양도, 비문사용률에서 유의미한 차이를 보였고, 구문복잡성, 철자오류에서는 유의미한 차이가 없었다. 경도지적장애 학생 집단 내 성별 간에는 유의미한 차이가 없었다. 이야기 문법의 하위 범주에서는 배경, 시도, 결과, 계기사건, 내적반응 순으로 많이 산출하였다. 본 연구의 결과를 통해 경도지적장애 학생의 이야기 쓰기 능력을 보면 다양한 이야기 문법과 어휘로 이야기를 표현하는 것에 어려움을 가지며, 문장 산출 시 비문사용이 높다는 것을 알 수 있다. The purpose of this study is using non-verbal animation to inquire the narrative writing abilities of the students with mild intellectual disability group. Narrative writing abilities were analyzed by story-grammar, syntactic complexity, semantic abilities, and finally syntactic accuracy. Among students with mild intellectual disabilities, the students who are 9 to 11 years old in language age and have not multiple disabilities. According to the study results, students with mild intellectual disability group obtained lower score than the same language age group in the story-grammar, total number of words, number of different words, syntax error. In the case of subcategory of story grammar, there can be listed according to frequency in a sequence of setting, attempts, consequence, initiating event and internal response When comparing these study results with other previous studies of narrative writing with mild intellectual disability subjects, there were have a narrative writing abilities but not using various words. Through these study results, it was found that student with a mild intellectual disability have a difficulty to express story with various story grammar, words and syntax errors.

Dosimetric Verifications of the Output Factors in the Small Field Less Than $3cm^2$ Using the Gafchromic EBT2 Films and the Various Detectors

오세안,예지원,이레나,박헌보,김성규,Oh, Se An,Yea, Ji Woon,Lee, Rena,Park, Heon Bo,Kim, Sung Kyu Korean Society of Medical Physics 2014 의학물리 Vol.25 No.4

The small field dosimetry is very important in modern radiotherapy because it has been frequently used to treat the tumor with high dose hypo-fractionated radiotherapy or high dose single fraction stereotactic radiosurgery (SRS) with small size target. But, the dosimetry of a small field (< $3{\times}3cm^2$) has been great challenges in radiotherapy. Small field dosimetry is difficult because of (a) a lack of lateral electronic equilibrium, (b) steep dose gradients, and (c) partial blocking of the source. The objectives of this study were to measure and verify with the various detectors the output factors in a small field (<3 cm) for the 6 MV photon beams. Output factors were measured using the CC13, CC01, EDGE detector, thermoluminescence dosimeters (TLDs), and Gafchromic EBT2 films at the sizes of field such as $0.5{\times}0.5$, $1{\times}1$, $2{\times}2$, $3{\times}3$, $5{\times}5$, and $10{\times}10cm^2$. The differences in the output factors with the various detectors increased with decreasing field size. Our study demonstrates that the dosimetry for a small photon beam (< $3{\times}3cm^2$) should use CC01 or EDGE detectors with a small active volume. And also, Output factors with the EDGE detectors in a small field (< $3{\times}3cm^2$) coincided well with the Gafchromic EBT2 films. 소조사면의 선량검증은 고선량을 1회에 치료하는 정위적방사선수술(Stereotactic radiosurgery, SRS)과 고선량을 소분할 하여 치료하는 소분할방사선치료(hypo-fractionated radiotherapy)에서 작은 크기의 종양을 치료하기 위해서 자주 사용되기 때문에 현대의 방사선치료에서 있어서 매우 중요하다. 그러나, $3cm^2$ 이하의 소조사면에 대한 선량검증은 방사선치료에서 있어서 대단한 도전이다. 소조사면의 선량검증은 (a) 측방전자균형(lateral electronic equilibrium)의 부족, (b) 급격한 선량 기울기(steep dose gradient), (c) 선원의 부분적 차폐 때문에 어렵다. 이 연구의 목적은 6 MV 광자선의 $3cm^2$ 이하의 소조사면에서 출력비율을 다양한 검출기로 측정하고 검증하는 것이다. 출력비율은 CC13 이온함, CC01 이온함, EDGE 검출기, 열발광선량계(thermoluminescence dosimeters, TLD), Gafchromic EBT2 필름을 이용하여 $0.5{\times}0.5cm^2$, $1{\times}1cm^2$, $2{\times}2cm^2$, $3{\times}3cm^2$, $5{\times}5cm^2$, $10{\times}10cm^2$의 다양한 조사면에서 측정하였다. 출력비율의 차이는 조사면의 크기가 작아질수록 검출기간의 차이는 증가하였다. 본 연구의 결과는 $3cm^2$ 이하의 소조사면의 선량측정은 CC01 이온함, EDGE 검출기와 같은 작은 크기의 방사부부피(active volume)를 가지는 검출기를 사용해야 한다는 것을 입증하였다. 또한, $3cm^2$ 이하의 소조사면에서 EDGE 검출기의 출력비율은 Gafchromic EBT2 필름의 결과와 잘 일치하였다.

선형가속기의 출력 특성에 대한 공정능력과 공정가능성을 이용한 통계적 분석

오세안,예지원,김상원,이레나,김성규,Oh, Se An,Yea, Ji Woon,Kim, Sang Won,Lee, Rena,Kim, Sung Kyu 한국의학물리학회 2014 의학물리 Vol.25 No.3

The purpose of this study is to evaluate the results for the quality assurance through a statistical analysis on the output characteristics of linear accelerators belonging to Yeungnam University Medical Center by using the Shewhart-type chart, Exponentially weighted moving average chart (EWMA) chart, and process capability indices $C_p$ and $C_{pk}$. To achieve this, we used the output values measured using respective treatment devices (21EX, 21EX-S, and Novalis Tx) by medical physicists every month from September, 2012 to April, 2014. The output characteristics of treatment devices followed the IAEA TRS-398 guidelines, and the measurements included photon beams of 6 MV, 10 MV, and 15 MV and electron beams of 4 MeV, 6 MeV, 9 MeV, 12 MeV, 16MeV, and 20 MeV. The statistical analysis was done for the output characteristics measured, and was corrected every month. The width of control limit of weighting factors and measurement values were calculated as ${\lambda}=0.10$ and L=2.703, respectively; and the process capability indices $C_p$ and $C_{pk}$ were greater than or equal to 1 for all energies of the linear accelerators (21EX, 21EX-S, and Novalis Tx). Measured values of output doses with drastic and minor changes were found through the Shewhart-type chart and EWMA chart, respectively. The process capability indices $C_p$ and $C_{pk}$ of the treatment devices in our institution were, respectively, 2.384 and 2.136 for 21EX, 1.917 and 1.682 for 21EX-S, and 2.895 and 2.473 for Novalis Tx, proving that Novalis Tx has the most stable and accurate output characteristics. 이 연구의 목적은 본원이 보유하고 있는 선형가속기들의 출력 특성을 Shewhart-type Chart, EWMA Chart, 공정능력지수 $C_p$와 $C_{pk}$을 이용한 통계적 분석으로 품질보증에 대한 결과를 평가하고자 한다. 측정값은 의학물리사에 의하여 2012년 9월부터 2014년 4월까지 매월 측정된 각각 치료기들(21EX, 21EX-S, Novalis Tx)의 출력측정값을 사용하였다. 치료기들의 출력 특성은 IAEA TRS-398의 가이드라인을 따랐으며, 측정 에너지는 광자선 6 MV, 10 MV, 15 MV와 전자선 4 MeV, 6 MeV, 9 MeV, 12 MeV, 16 MeV, 20 MeV였다. 매월 측정하여 교정한 출력특성에 대한 통계학적 분석이며, 가중인자와 측정값의 관리한계의 폭은 ${\lambda}=0.10$, L=2.703로 계산되었으며, 공정능력 $C_p$와 $C_{pk}$는 모든 선형가속기(21EX, 21EX-S, Novalis Tx)의 모든 에너지에서 1이상이었다. Shewhart-type Chart를 통하여 출력선량의 측정값의 큰 변화점을 찾을 수 있었고, EWMA Chart를 통하여 출력선량의 측정값의 미세한 변화점을 알아 볼 수 있었다. 본원의 치료기의 공정능력지수 $C_p$와 $C_{pk}$를 통하여 21EX가 2.384와 2.136, 21EX-S가 1.917과 1.682, Novalis Tx가 2.895와 2.473으로 Novalis Tx가 가장 안정적이고 정확한 출력특성을 나타내고 있었다.

Whole brain radiotherapy using four-field box technique with tilting baseplate for parotid gland sparing

박재현,예지원 대한방사선종양학회 2019 Radiation Oncology Journal Vol.37 No.1

Purpose: The aim of this study is to evaluate the efficacy and feasibility of four-field box whole brain radiotherapy (FB-WBRT) with tilting baseplate by comparing bilateral WBRT (B-WBRT). Methods and Materials: Between March 2016 and September 2018, 20 patients with brain metastases underwent WBRT using the four-field box technique. WBRT is performed with a dose of 30 Gy in 10 fractions daily. Two computed tomography simulations per person were performed. One was in the traditional supine position for B-WBRT and the other by applying the tilting acrylic supine baseplate to elevate the head by 40° for FB-WBRT. The B-WBRT used the field-in-field technique, which is the most commonly used method in our institution. The FB-WBRT comprised anterior, posterior, and bilateral beams. A wedge was applied in anterior and posterior fields to compensate for skull convexity. Results: The average of Dmean of both parotid glands was 10.2 Gy (range, 3.8 to 17.8 Gy) in B-WBRT and 5.4 Gy (range, 2.0 to 11.7 Gy) in FB-WBRT (p < 0.05). Compared to B-WBRT, FB-WBRT reduced the mean dose of the right and left parotid glands from 10.1 Gy to 4.9 Gy and from 10.4 Gy to 5.8 Gy, respectively (p < 0.05). Further, V5, V10, V15, V20, and V25 for the parotid gland decreased significantly in FB-WBRT (p < 0.05). The Dmax and Dmean of lens decreased according to the dose-volume histogram. Conclusion: Compared to B-WBRT, FB-WBRT with a tilting baseplate is a simple and effective method that takes feature of noncoplanar beam to protect the parotid gland.

Reductions in the Variations of Respiration Signals for Respiratory-gated Radiotherapy When Using the Video-coaching Respiration Guiding System

이현정,예지원,오세안 한국물리학회 2015 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.67 No.1

Respiratory-gated radiation therapy (RGRT) has been used to minimize the dose to normal tissue in lung-cancer radiotherapy. The present research aims to improve the regularity of respiration in RGRT by using a video-coached respiration guiding system. In the study, 16 patients with lung cancer were evaluated. The respiration signals of the patients were measured by using a realtime position management (RPM) respiratory gating system (Varian, USA), and the patients were trained using the video-coaching respiration guiding system. The patients performed free breathing and guided breathing, and the respiratory cycles were acquired for 5 min. Then, Microsoft Excel 2010 software was used to calculate the mean and the standard deviation for each phase. The standard deviation was computed in order to analyze the improvement in the respiratory regularity with respect to the period and the displacement. The standard deviation of the guided breathing decreased to 48.8% in the inhale peak and 24.2% in the exhale peak compared with the values for the free breathing of patient 6. The standard deviation of the respiratory cycle was found to be decreased when using the respiratory guiding system. The respiratory regularity was significantly improved when using the video-coaching respiration guiding system. Therefore, the system is useful for improving the accuracy and the efficiency of RGRT.

Standard Exact Couch와 6D Robotic Couch를 이용한 광자선의 조사각에 따른 선량 감쇠에 대한 연구

김태형,오세안,예지원,박재원,김성규,Kim, Tae Hyeong,Oh, Se An,Yea, Ji Woon,Park, Jae Won,Kim, Sung Kyu 한국의학물리학회 2016 의학물리 Vol.27 No.2

본 연구는 방사선치료에서 방사선 선량전달의 정확도를 높이기 위해 두 종류의 치료테이블 6D robotic couch (BrainLab, Feldkirchen, Germany)와 Standard exact couch (Varian Exact couch$^{TM}$, Varian Medical Systems, Milpitas, CA, USA)를 이용하여 Rail의 위상(In-Out)에 따른 상대선량을 측정하여, 선량감쇠율을 계산하였다. 치료테이블을 투과하는 조사에너지의 조사각 $0^{\circ}$에서 $360^{\circ}$까지의 상대 선량을 각각 측정하였으며, 조사각이 $0^{\circ}$일 때 측정된 선량을 기준으로 하여 $5^{\circ}$ 간격으로 선량의 변화를 측정하고 선량 감쇠율을 계산하였다. Standard exact couch의 광자선 에너지는 6 MV와 10 MV를 사용하였으며 치료테이블의 Rail 위상(In position, Out position)에 따른 상대 선량을 측정하였다. 6D robotic couch는 6 MV와 15 MV의 광자선 에너지를 사용하였다. Standard exact couch의 광자선의 최대 선량차이는 Rail In position에서 6 MV ($175^{\circ}$), 10 MV ($175^{\circ}$)일 때, 선량차이는 각각 16.53%, 12.42%, Out position에서 6 MV ($225^{\circ}$), 10 MV ($225^{\circ}$)일 때, 선량차이는 각각 15.15%, 9.96%였다. 6D robotic couch에서는 6 MV ($130^{\circ}$)와 15 MV ($130^{\circ}$)일 때, 선량차이는 각각 6.82%, 4.92%였다. 본 연구를 통해, 치료테이블의 종류에 따른 선량 감쇠율은 6D robotic couch가 Standard exact couch보다 6 MV에서 조사각 $180^{\circ}$ 기준 약 1% 더 발생함을 확인하였고, Stnadard exact couch인 경우, Sliding rail의 위상(In position, Out position)에 따라 선량 감쇠가 급격히 변화하는 것을 확인하였다. The objective of this study is to increase the accuracy of dose transmission in radiation therapy using two types of treatment tables, standard exact couch (Varian 21EX, Varian Medical Systems, Milpitas, CA) and 6D robotic couch (Novalis, BrainLAB A.G., Heimstetten, Germany)). We examined the dose attenuation based on the two types of treatment tables and studied the dose of attenuation using the phase (In/Out) for the standard exact couch. We measured the relative dose according to the incident angle of a penetrative photon beam under a treatment table. The incident angle of the photon beam was from $0^{\circ}$ to $360^{\circ}$ in the increments of $5^{\circ}$. The reference angle was set to $0^{\circ}$. Furthermore, the relative dose of the 6D robotic couch was measured using 6 MV and 15 MV, and that of the standard exact couch was measured at the sliding rail position (In-Out) using 6 MV and 10 MV. In the case of the standard exact couch, the measured relative dose was 16.53% (rails at the "In position," $175^{\circ}$, 6 MV), 12.42% (rails at the "In position," $175^{\circ}$, 10 MV), 13.13% (rails at the "Out position," $175^{\circ}$, 6 MV), and 9.96% (rails at the "Out position," $175^{\circ}$, 10 MV). In the case of the 6D robotic couch, the measured relative dose was 6.82% ($130^{\circ}$, 6 MV) and 4.92% ($130^{\circ}$, 15 MV). The photon energies were surveyed at the same incident angle. The dose attenuation for an energy of 10 MV was 4~5% lower than that for 6 MV. This indicated that the higher photon energy, lesser is the attenuation. The results of this study indicated that the attenuation rate for the 6D robotic couch was confirmed to be 1% larger than that for the standard exact couch at 6 MV and $180^{\circ}$. In the case of the standard exact couch, the dose attenuation was found to change rapidly in accordance with the phase ("In position" and "Out position") of the sliding rail.