• 한국방사선학회논문지
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• 제14권5호
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• pp.523-528
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• 2020

반려견의 사망원인 1위인 암 중 암컷에게서 가장 높은 발생률을 보이는 유방암을 대상으로 근접방사선치료 수행 시 모의모사를 이용한 흡수선량 측정을 바탕으로 적용성을 평가하고자 하였다. 모의모사를 위해 MCNPX 프로그램을 이용하였으며, 흡수선량 측정을 위해 소형견 크기의 수학적 팬텀을 제작 하였다. 흡수선량 측정결과 종양의 경우 ¹⁹²Ir에서 1.02E-12 Gy/#으로 흡수선량이 가장 높은 것으로 나타났으며, 내·외부 흡수선량에서도 동일한 경향성으로 나타났다. 따라서 반려견 유방암의 근접방사선치료 시 견종과 피폭을 고려한 적절한 선원의 선택이 고려되어야 될 것이다.

• 한국방사선학회논문지
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• 제10권4호
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• pp.271-278
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• 2016

본 연구는 유방암의 근접치료 시 수학적 모의피폭체를 이용하여 유방 및 인접장기의 선량을 평가하고자 하였다. 좌측 유방과 우측 유방을 선원으로 설정하여 $^{192}Ir$과 $^{103}Pd$ 핵종에 대한 흡수선량을 분석하였다. 그 결과 선원 장기에 대한 선량은 $^{192}Ir$이 $^{103}Pd$에 비해 높은 흡수선량을 보였으며, 반대측 유방의 선량도 $^{192}Ir$이 높게 나타났다. 또한 유방암의 근접치료 시 특히 유의해야 할 인접장기는 폐, 간, 심장, 반대측 유방으로 평가되었다.

• Radiation Oncology Journal
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• 제9권2호
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• pp.319-324
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• 1991

여성 뇨도암은 극히 드문 종양으로 그 치료법에 대해서는 수술과 방사선 치료가 주종을 이룬다. 본원에서 micro Selectron ${I_r}-192$를 이용하여 원격조정 고선량 근접치료를 시행했는데 시술의 기술적인 측면을 소개하고 문헌고찰을 기술한다.

• 대한방사선기술학회지:방사선기술과학
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• 제42권2호
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• pp.131-135
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• 2019

The purpose of this study was to evaluate the efficacy of brachytherapy of breast cancer by dose assessment which a steady increased in Korea women. The dose assessment was performed using the MCNPX program, a MonteCarlo simulation technique. The sources used for brachytherapy was 192Ir. And nanoparticle which used for dose enhancement was gold. The density of nanoparticle was 7, 18 and 30 mg. Evaluation of absorbed dose according to distance is measured at a distance of 30, 50, 100 and 200 cm from the patient. As a result, The breast absorbed dose results increased in proportion to the density of nanoparticle. And the surrounding organs were not significantly different according to the density. But, in some organs, the absorbed dose decreased as the density of nanoparticles increased. Absorbed dose according to the distance was in inverse proportion to distance.

• Nuclear Engineering and Technology
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• 제55권8호
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• pp.2734-2741
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• 2023

Brachytherapy is a special case of radiotherapy. It should be arranged according to some principles in medical radiation applications and radiation physics. The primary principle is to use as low as reasonably achievable dose in all ionizing radiation applications for diagnostic and therapeutic treatments. Dosimetric distributions are dependent on radioactive source properties and radiation-matter interactions in an absorber medium such as phantom or tissue. In this consideration, the geometrical structure and material of the seed capsule, which surrounds a radioactive material, are directly responsible for isodose profiles and dosimetric functions. In this study, the radiometric properties of capsule material were investigated on dose distribution in a water phantom by changing its nuclear properties using the EGSnrc Monte Carlo (MC) simulation code. Effective atomic numbers of hypothetic mixtures were calculated by using different elements with several fractions for capsule material. Model 6711 brachytherapy seed was modeled by EGSnrc/Dosrcnrc Code and dosimetric functions were calculated. As a result, dosimetric parameters of hypothetic sources have been acquired in large-scale atomic number. Dosimetric deviations between the data of hypothetic seeds and the original one were analyzed. Unit dose (Gy/Particle) distributions belonging to different types of material in seed capsule have remarkably differed from the original capsule's data. Capsule type is major variable to manage the expected dose profile and isodose distribution around a seed. This study shows us systematically varied scale of material type (cross section or effective atomic number dependent) offers selective material usage in production of seed capsules for the expected isodose profile of a specific source.

• Radiation Oncology Journal
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• 제13권1호
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• pp.27-31
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• 1995

Purpose : This study was done to evaluate preliminarily the role of intraluminal brachytherapy in the radiation treatment of non-metastatic esophageal cancer, Materials and Methods: We analyzed follow-up result of 21 patients treated at the dept. of therapeutic radiology in Gyeongsang national university hospital between April, 1989 and August, 1992. All patients received neoadjuvant chemotherapy(5-FU, Cispl-atin). Fifteen Patients were treated with external beam alone, and in remaining 6 patients, the external beam radiotherapy followed by intraluminal brachytherapy was done. Results : Among 21 patients, 7 patients showed complete tumor regression after completion of radiotherapy. But 2 of these complete responder recurred at the site of primary disease, so ultimate local control rate was $23.8\%$(5/21). Local control rate according to radiation treatment modality was $6.7\%$(1/15) in patients treaed with external irradiation only, and $66.7\%$ in patients treated with combined external irradiation and intraluminal brachytherapy. The 2 year NED survival rate was $6.6.\%$ in the former and $66.7\%$ in the latter. Conclusion: Although there should be consideration about case selection for addition of intraluminal brachytherapy intraluminal brachytherapy may be considerded as one of the method to enhance the local control probability of esophageal cancer.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2002년도 Proceedings
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• pp.150-153
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• 2002

High dose rate (HDR) brachytherapy in the treatment of cervix carcinoma has become popular, because it eliminated many of the problems with conventional brachytherapy. In order to improve clinical effectiveness with HDR brachytherapy, dose calculation algorithm, optimization procedures, and image registrations should be verified by comparing the dose distributions from a planning computer and those from a humanoid phantom irradiated. Therefore, the humanoid phantom should be designed such that the dose distributions could be quantitatively evaluated by utilizing the dosimeters with high spatial resolution. Therefore, the small size of thermoluminescent dosimeter (TLD) chips with the dimension of 1/8" and film dosimetry with spatial resolution of <1mm used to measure the radiation dosages in the phantom. The humanoid phantom called a pelvic phantom is made of water and tissue-equivalent acrylic plates. In order to firmly hold the HDR applicators in the water phantom, the applicators are inserted into the grooves of the applicator supporters. The dose distributions around the applicators, such as Point A and B, can be measured by placing a series of TLD chips (TLD-to- TLD distance: 5mm) in three TLD holders, and placing three verification films in orthogonal planes.

• Radiation Oncology Journal
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• 제32권4호
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• pp.238-246
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• 2014

Purpose: To evaluate the clinical outcome of high-dose-rate (HDR) interstitial brachytherapy (IBT) in patients with oral cavity cancer. Materials and Methods: Sixteen patients with oral cavity cancer treated with HDR remote-control afterloading brachytherapy using $^{192}Ir$ between 2001 and 2013 were analyzed retrospectively. Brachytherapy was administered in 11 patients as the primary treatment and in five patients as salvage treatment for recurrence after the initial surgery. In 12 patients, external beam radiotherapy (50-55 Gy/25 fractions) was combined with IBT of 21 Gy/7 fractions. In addition, IBT was administered as the sole treatment in three patients with a total dose of 50 Gy/10 fractions and as postoperative adjuvant treatment in one patient with a total of 35 Gy/7 fractions. Results: The 5-year overall survival of the entire group was 70%. The actuarial local control rate after 3 years was 84%. All five recurrent cases after initial surgery were successfully salvaged using IBT ${\pm}$ external beam radiotherapy. Two patients developed local recurrence at 3 and 5 months, respectively, after IBT. The acute complications were acceptable (${\leq}grade$ 2). Three patients developed major late complications, such as radio-osteonecrosis, in which one patient was treated by conservative therapy and two required surgical intervention. Conclusion: HDR IBT for oral cavity cancer was effective and acceptable in diverse clinical settings, such as in the cases of primary or salvage treatment.

• Asian Pacific Journal of Cancer Prevention
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• 제15권8호
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• pp.3619-3623
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• 2014

Background: The aim of the study was to evaluate the vaginal dose and toxicity in patients of cervical cancer treated with image guided brachytherapy at our institute. Materials and Methods: Thirty-five patients treated with image based brachytherapy for cervical cancer were included. Vaginal contouring was done on MRI at brachytherapy and with CT scans of subsequent brachytherapy fractions. Dose volume parameters (DVH) were reported in accordance with the GEC-ESTRO guidelines. These were correlated with vaginal toxicity (assessed by CTCAE version 3) and quality of sexual life assessed at one year of completion of treatment. Results: Vaginal shortness was observed in 22 out of 30 (62.8%) patients, Nine (25.7%) had vaginal dryness and in 10 (28.5%) patients, there was contact bleeding. No association could be demonstrated between the dose volume parameters and vaginal toxicity in the present study. Conclusions: The lack of association between dose volume parameters of vagina with vaginal morbidity may be due to uncertainties involved in the delineation of vaginal wall and dosimetry. Future research is required to accurately define vaginal dose distribution to study its correlation with vaginal morbidity. Vaginal morbidity needs to be documented in order to improve the sexual outcome in these patients.

• Radiation Oncology Journal
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• 제14권4호
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• pp.299-306
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• 1996

목적 : 주요 기도의 악성 종양으로 인한 호흡기 증상은 적절한 조치를 취하지 않을 경우 때로는 환자의 생명을 위협할 정도로 위급한 경우가 있으며 환자의 삶의 질을 저하시키는 주요 원인이 된다. 이러한 호흡기 증상의 완화를 위하여 적용한 기관지 내시경을 이용한 고선량율 기관내 근접 조사 방사선차료의 단기 임상 관찰 결과를 보고하고자 한다. 대상 및 방법 : 1994년 12월부터 1996년 3월까지 원발성 또는 전이성 폐암으로 인한 기도폐쇄 와 이로 인한 주요 호흡기 증상이 있는 25명의 환자들에 대하여 고선량율 기관내 근접 조사 방사선치료를 시술하였다. 원발 병소는 비소세포성 폐암이 21례 ($84\%$), 원발성 기관암이 3례($12\%$), 재발된 식도암이 1례였다. 20명의 환자들에 대하여는 외부 조사 방사선치료를 병행하였으며, 급성 기도 폐쇄로 위급한 증상을 호소하였던 6명의 환자에 대하여는 응급 기관내 Laser 소작술을 먼저 시행하였다. 기관내 근접 조사 방사선치료는 모든 환자에서 각 3회씩 시행하도록 예정하였으며 모두 70회의 치료를 시행하였다. 결과 : 기관내 근접 조사 방사선치료의 전후로 조사한 주요 호흡기 증상은 기침, 호흡곤란, 각혈, 폐쇄성 폐렴이 각각 $88\%$ (22/25), $96\%$ (22/23), $100\%$ (15/15), $100\%$ (9/9)에서 호전되었으며, 환자의 일반 활동도 (ECOG performance score)는 전체 환자의 $56\%$에서 호전되었고 악화된 경우는 없었다. 관찰 기간 동안 15명이 사망하였으며 치료 개시로부터 사망까지 기간의 중앙값은 4개월 (범위: 1개월$\~$17개월) 이었고 10명의 생존자들의 생존 기간의 중앙값은 9개월 (범위: 5개월$\~$19개월)이었다. 치료 후 1년 이상 생존한 환자는 5명이었으며 이들 모두에선 원발 병소의 완전 관해를 확인할 수 있었다. 사망자들은 모두 원발 및 전이 병소의 진행으로 인한 경우였다. 대량 각혈로 사망한 경우는 4명이었으며 이 중 3명은 응급 기관내 Laser 소작술을 선행하였던 경우였다. 결론 : 기관지 내시경을 이용한 기관내 근접 조사 방사선 치료는 기도의 악성 병변시 호흡기 증상 및 환자의 활동도를 호전시키는 데 매우 효과적인 치료 방법이다. 저자들의 관찰 경험을 바탕으로 하여 기관내 근접 조사 방사선치료는 근치적 방사선치료의 국소 추가 방사선 조사의 한 방법으로 적용할 수 있을 것으로 판단된다.