Modeling the Biophysical Effects in a Carbon Beam Delivery Line by Using Monte Carlo Simulations

Ilsung Cho,SeungHoon Yoo,Sungho Cho,Eun Ho Kim,Yongkeun Song,Jae-ik Shin,Won-Gyun Jung 한국물리학회 2016 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.69 No.5

The Relative biological effectiveness (RBE) plays an important role in designing a uniform dose response for ion-beam therapy. In this study, the biological effectiveness of a carbon-ion beam delivery system was investigated using Monte Carlo simulations. A carbon-ion beam delivery line was designed for the Korea Heavy Ion Medical Accelerator (KHIMA) project. The GEANT4 simulation tool kit was used to simulate carbon-ion beam transport into media. An incident energy carbon-ion beam with energy in the range between 220 MeV/u and 290 MeV/u was chosen to generate secondary particles. The microdosimetric-kinetic (MK) model was applied to describe the RBE of 10% survival in human salivary-gland (HSG) cells. The RBE weighted dose was estimated as a function of the penetration depth in the water phantom along the incident beam’s direction. A biologically photon-equivalent Spread Out Bragg Peak (SOBP) was designed using the RBEweighted absorbed dose. Finally, the RBE of mixed beams was predicted as a function of the depth in the water phantom.

Consideration of the benefits of using a high current accelerator in BNCT

Cho, Ilsung,Min, Sun-Hong,Park, Chawon,Kim, Minho,Lee, Kyo Chul,Lee, Yong Jin,Hong, Bong Hwan,Lim, Sang Moo 대한방사성의약품학회 2020 Journal of radiopharmaceuticals and molecular prob Vol.6 No.1

Boron Neutron Capture Therapy (BNCT) has the advantage of selectively removing cancer cells ingesting boron compounds. In this study, the benefits for treatment time and boron compound injection dose were compared between current neutron sources and a high current neutron sources to be developed in near future. The time-activity curve (TAC) of GBM (Glioblastoma) for one bolus injection was obtained by applying modified 3 compartment model. The treatment time was determined for an accelerator-based neutron sources at the present time and a high current accelerator based neutron source to be developed in the near future. In the case of the double amount of IAEA-recommended neutron flux, the treatment time was shortened to 15 minutes. In the case of high current accelerators, which are five times the amount of IAEA-recommended neutron flux, the irradiation time is within 5 minutes. The use of a high current accelerator based neutron source in BNCT is advantageous in terms of treatment time. In addition, it can increase the efficiency of use of neutrons and reduce the boron compound injection dose to patients, thus reducing pharmacological toxicity.

Estimation of the medical need for carbon-ion radiotherapy in Korea

Cho, Ilsung,Seo, Young Seok,Jung, WonGyun,Kim, Mi-sook JAPAN RADIATION RESEACH SOCIETY 2018 JOURNAL OF RADIATION RESEARCH Vol.59 No.5

<P><B>Abstract</B></P><P>The Korea Heavy Ion Medical Accelerator project focuses on the development of medical accelerator facilities for delivering carbon-ion beams to cancer patients. The purpose of the present study was to estimate the clinical need for carbon-ion therapy in Korea. Seven tumor sites, namely head and neck, liver, lung, colon and rectum, prostate, bone and soft tissue, and pancreas were selected as eligible sites for receiving carbon-ion radiotherapy (RT) by radiation oncologists of the Korea Institute of Radiological and Medical Sciences. Cancer incidence data for the selected tumor sites were obtained from the Korea National Cancer Incidence Database in order to estimate the potential medical need for carbon-ion RT. The carbon-ion RT adaption rate was assessed based on the clinical experience of other carbon-ion therapy facilities. An estimation model was constructed for estimating the medical need for carbon-ion RT, and from this, 25 606 patients were deemed to be potential candidates for carbon-ion RT. This estimated potential need corresponded to 10% of newly diagnosed cancer patients in Korea. The realistic estimation was calculated as ranging between 4000 and 6300 patients, depending on the carbon-ion RT adaptation rate. This estimated medical need corresponded to 2–3% of newly diagnosed cancer patients in Korea. Taken together, our findings suggest that there is a clear medical need for carbon-ion RT in Korea, with at least 4000 potential patients per year.</P>

간암에 대한 양성자 치료계획에서 셋업 오차와 문지름 인자에 따른 불확실성의 대한 평가

조성호(SungHo Cho),유승훈(SeungHoon Yoo),조일성(IlSung Cho),송용근(YongKeun Song),신재익(JaeIk Shin),김은호(EunHo Kim),정원균(WonGyun Jung) 한국방사선학회 2015 한국방사선학회 학술대회 논문집 Vol.2015 No.춘계

We investigated the effect of set-up error and smearing factor in proton therapy for liver cancer under the artificial movement of isocenter of target volume and adjustment of smearing factor using treatment planning system. The plans were the clinically designed passive scattered treatment plans in Eclipse v9.8 (Varian Medical Systems, Palo Alto, CA) according to RTOG protocol. The artificial movement of isocenter in target volume is from -1 cm to 1cm along to x, y, z axis based on the position of original target volume. Also, smearing factor is adjusted from 0.3 to 1.2. To compare the dose conformity evaluation by set-up error and smearing factor, we used Dmax, Dmin, Dmean and conformity index(CI) and inhomogeneity coefficient(IC). The conformity index and inhomogeneity coefficient of the dose in the target volumes was respectively calculated using the formula (Dmax-Dmin)/Dmean and VDP/Vtarget, where VDPis the volume enclosed by the prescribed isodose surface, i.e., prescription dose and Vtarget is the volume of normalization target. As a results, for the X-axis setup error, there is no difference in value of Dmax and Dmin within ± 0.5cm setup errors, however it was rapidly increased beyond the ±0.5cm setup errors. Y axis and Z axis setup errors also showed a similar trend as X-axis. In the case of smearing factor, there is little difference in Dmax and Dmin when smearing factor has high value, inhomogeneity under no setup errors was 14.05, 11.5 and 8.8 in 0.3, 0.7 and 1.2 smearing factor, respectively. Therefore, smearing factor is very important parameter in particle therapy because it can adjust the dose distribution. 양성자를 이용한 간암치료 시 환자 위치 에러와 문지름 인자에 따른 영향을 분석하기 위해서 치료계획 시스템을 이용하 여 인공적인 타켓볼륨의 중심점 이동과 문지름 인자의 조절에 대한 영향을 분헉하였다. 치료계획은 이클립스 9.8을 이용 하여 스캐터링 방식의 치료 방식으로 설계하였다. 타켓 볼륨의 중심점이동은 X, Y, Z 세 방향으로 -1에서 1cm 까지 이동하였으며, 문지름 인자는 0.3에서 1.2로 이용하였다. 환자위치 에러와 문지름 팩터에 따른 선량 분포를 비교하기 위하여 우리는 Dmax, Dmin, Dmean, Conformity index(CI)와 비균질상수를 사용하였다. 그 결과 X축 환자위치에 따라서 ± 0.5cm 이내에서는 Dmax, Dmin 차이가 나타나지 않았으나 이후에는 큰 차이를 보였다. Y, Z축 에러도 비슷한 분포를 보였다. 문지름 인자의 경우 높은 값을 사용할 때는 Dmax, Dmin 의 차이가 나타나지 않았으나 낮은 값을 사용할 때는 큰 차이를 보였다. 따라서 환자위치 와차와 문지름 인자는 입자치료에서 선량 분포를 조절할 수 있기 때문에 매우 중요한 파라미터이다.

중이온 치료연구센터의 현황

조성호(Sunho Cho),유승훈(Seunghoon Yoo),조일성(Ilsung Cho),김은호(Eunho Kim),신재익(Jaeik Shin),송용근(Yonggeun song),정원균(Wonjyun Jung) 한국방사선학회 2014 한국방사선학회 학술대회 논문집 Vol.2014 No.추계

Recently, particle therapy has received considerable attention worldwide due to higher dose conformation of particle beam to photon beam, and currently there are many centers under construction. In KIRAMS, we are constructing a new treatment facility for heavy ion therapy since 2010. We have 3 treatment room and 1 research room, and we have 2 scanning beam and 1 broad beam for the treatment room. For each treatment room, there are irradiation system, patient positioning system and dose verification system. Also, there are treatment planning system and control system for the heavy ion therapy. In this paper, our protocol for the construction of treatment system is presented and detailed specification and methods are reported. 포톤빔에 비해 좋은 선량 분포로 인해 최근에 전 세계적으로 입자치료에 대한 관심이 높아지고 있으며, 현재 수 많은 센터가 건설되고 있다. 이에 KIRAMS에서도 2010년도부터 중입자치료를 위한 센터를 구축하고 있다. 우리의 센터는 3개의 치료실과 1개의 연구용 조사실로 구성되어 있으며, 치료실은 2개의 스캐닝 빔과 1개의 브로드빔으로 구성되어있다. 각 치료실은 치료를 위한 조사시스템, 환자위치시스템, 선량검증시스템으로 구성되어 있으며, 치료를 위한 선량계산시스템을 비롯하여 제어시스템 등으로 구성된다. 본 논문에서는 이러한 치료시스템 구축을 위한 KIRAMS의 방법을 제시하고, 이에 관한 세부적인 사항을 보고한다.

Terahertz (THz) imaging technology for therapeutic and diagnostic applications of cancer incorporating with radiopharmaceutical fields

Min, Sun-Hong,Cho, Ilsung,Park, Chawon,Jung, Wongyun,Hwang, Won Taek,Kim, Minho,Lee, Kyo Chul,Lee, Yong Jin,Lim, Sang Moo,Hong, Bong Hwan 대한방사성의약품학회 2019 Journal of radiopharmaceuticals and molecular prob Vol.5 No.2

Radiopharmaceuticals include therapeutic radiopharmaceuticals and diagnostic radiopharmaceuticals. Therapeutic radiopharmaceuticals are administered to the body and ingested at specific organs to detect radiation emitted from the site and to construct an image to diagnose the disease. Diagnostic radiopharmaceuticals are used to treat diseases by killing cells with radiation emitted from radiopharmaceuticals, such as cancer cells, vascular endothelial cells, arthritis, and Alzheimer's disease. The application possibilities of terahertz imaging technology for the combination of radiopharmaceuticals and molecular imaging medicine are discussed and experimental methods are presented. Terahertz imaging is expected to be a powerful technique because of the effective piercing feasibility, which enables to perform safe and high resolutive imaging. To investigate the response of cell to the terahertz wave, both the pulsed and CW THz wave systems are employed. THz imaging of a rat's paraffin-embedded epithelial cell with tumor is studied in advance.

Experimental Transverse Beam Emittance Measurement Using Solenoid Magnet Strength Variation in AB-BNCT

Hong Bong-Hwan,Cho Ilsung,Min Sun-Hong,Park Seungwoo,Kim Minho,Jung Hyunwoo,박차원 한국물리학회 2020 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.77 No.12

Boron neutron capture therapy (BNCT) is a more efficient cancer treatment method compared to direct radiation therapy using charged particles such as protons or carbon beams. Particularly, accelerator-based BNCT (AB-BNCT) is attracting attention due to easy construction in a hospital. The Korea Institute of Radiological & Medical Sciences (KIRAMS) has constructed an injection system for an electrostatic AB-BNCT accelerator and commissioned 30 keV H- and 5 keV D- ion beam facilities. The beam characteristic parameters and Twiss parameters should be confirmed experimentally, and various methods have to be applied for the related measurements. In this study, the linear matrix formalism is used as a technique to measure the beam characteristic and Twiss parameters by varying the magnetic field strength of a solenoid in the beam line. To confirm the validity of this method, a multi-particle tracking code was executed. The simulation results confirm that the proposed method is effective for extracting Twiss parameters. After verification via the multi-particle tracking code, the method was applied to perform experimental measurements. Notably, the method accurately obtains the transverse beam emittance within reasonable uncertainty levels. Thus, our results show that the proposed method is a convenient technique for extracting the Twiss parameters indirectly. The results of the Twiss parameter measurement can potentially be more precise if other aspects, such as the quadrupole magnetic field strength, are incorporated.

Design of a scintillator-based prompt gamma camera for boron-neutron capture therapy: Comparison of SrI₂ and GAGG using Monte-Carlo simulation

Kim, Minho,Hong, Bong Hwan,Cho, Ilsung,Park, Chawon,Min, Sun-Hong,Hwang, Won Taek,Lee, Wonho,Kim, Kyeong Min Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.2

Boron-neutron capture therapy (BNCT) is a cancer treatment method that exploits the high neutron reactivity of boron. Monitoring the prompt gamma rays (PGs) produced during neutron irradiation is essential for ensuring the accuracy and safety of BNCT. We investigate the imaging of PGs produced by the boron-neutron capture reaction through Monte Carlo simulations of a gamma camera with a SrI₂ scintillator and parallel-hole collimator. GAGG scintillator is also used for a comparison. The simulations allow the shapes of the energy spectra, which exhibit a peak at 478 keV, to be determined along with the PG images from a boron-water phantom. It is found that increasing the size of the water phantom results in a greater number of image counts and lower contrast. Additionally, a higher septal penetration ratio results in poorer image quality, and a SrI₂ scintillator results in higher image contrast. Thus, we can simulate the BNCT process and obtain an energy spectrum with a reasonable shape, as well as suitable PG images. Both GAGG and SrI₂ crystals are suitable for PG imaging during BNCT. However, for higher imaging quality, SrI₂ and a collimator with a lower septal penetration ratio should be utilized.

Optimum Condition of Spot size and spacing in Particle Scanning Irradiation

Hye Jeong Yang,Seung Hoon Yoo,Ilsung Cho,Sungho Cho,Yongkeun Song,Jae-ik Shin,Eun Ho Kim,Won-Gyun Jung 대한방사선방어학회 2015 대한방사선방어학회 학술발표회 논문요약집 Vol.2015 No.10

Terahertz (THz) imaging technology for therapeutic and diagnostic applications of cancer incorporating with radiopharmaceutical fields

Sun-Hong Min,Bong Hwan Hong,Ilsung Cho,Chawon Park,Wongyun Jung,Won Taek Hwang,Minho Kim,Kyo Chul Lee,Yong Jin Lee,Sang Moo Lim 대한방사성의약품학회 2019 Journal of radiopharmaceuticals and molecular prob Vol.5 No.2

Radiopharmaceuticals include therapeutic radiopharmaceuticals and diagnostic radiopharmaceuticals. Therapeutic radiopharmaceuticals are administered to the body and ingested at specific organs to detect radiationemitted from the site and to construct an image to diagnose the disease. Diagnostic radiopharmaceuticals areused to treat diseases by killing cells with radiation emitted from radiopharmaceuticals, such as cancer cells,vascular endothelial cells, arthritis, and Alzheimer's disease. The application possibilities of terahertz imagingtechnology for the combination of radiopharmaceuticals and molecular imaging medicine are discussed andexperimental methods are presented. Terahertz imaging is expected to be a powerful technique because ofthe effective piercing feasibility, which enables to perform safe and high resolutive imaging. To investigate theresponse of cell to the terahertz wave, both the pulsed and CW THz wave systems are employed. THz imagingof a rat’s paraffin-embedded epithelial cell with tumor is studied in advance.