• Radiation Oncology Journal
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• 제16권4호
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• pp.357-366
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• 1998

Brachytherapy is an essential part of radiotherapy for uterine cervical cancer. The low dose rate (LDR) regimen has been the major technique of intracavitary therapy for cervical cancer. However, there has been an expansion in the last 20 years of high dose rate (HDR) machines using Ir-192 sources. Since 1979, HDR brachytherapy has been used for the treatment of uterine cervical cancer in Korea. The number of institutions employing HDR has been increasing, while the number of low dose rate system has been constant. In 1995, there was a total 27 HDR brachytherapy units installed and 1258 cases of patients with cervical cancer were treated with HDR Most common regimens of HDR brachytherapy are total dose of 30-39 Gy at point A with 10-13 fractions in three fractions per week. 24-32 Gy with 6-8 fractions in two fractions per week, and 30-35 Gy with 6-7 fractions in two fractions per week. The average fractionation regimen of HDR brachytherapy is about 8 fractions of 4.1 Gy each to Point A. In Korea, treatment results for HDR brachytherapy are comparable with the LDR series and appears to be a safe and effective alternative to LDR therapy for the treatment of cervical carcinoma. Studies from the major centers report the five-year survival rate of cervical cancer as. 78-86$\%$ for Stage 1, 68-85$\%$ for stage 11, and 38-56$\%$ for Stage III. World-wide questionnaire study and Japanese questionnaire survey of multiple institutions showed no survival difference in any stages and dose-rate effect ratio (HDR/LDR) was calculated to be 0.54 to 0.58. However the optimum treatment doses and fractionation schemes appropriate to generate clinical results comparable to conventional LDR schemes have yet to be standardized. In conclusion, HDR intracavitary radiotherapy is increasingly practiced in Korea and an effective treatment modality for cervical cancer. To determine the optimum radiotherapy dose and fractionation schedule, a nation-wide prospective study is necessary in Korea. In addition, standardization of HDR application (clinical, computer algorithms, and dosimetric aspects) is necessary.

• Asian Pacific Journal of Cancer Prevention
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• 제16권16호
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• pp.7167-7170
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• 2015

Background: Although 3D image based brachytherapy is currently the standard of treatment in cervical cancer, most of the centres in developing countries still practice orthogonal intracavitary brachytherapy due to financial constraints. The quest for optimum dose and fractionation schedule in high dose rate (HDR) intracavitary brachytherapy (ICBT) is still ongoing. While the American Brachytherapy Society recommends four to eight fractions of each less than 7.5 Gy, there are some studies demonstrating similar efficacy and comparable toxicity with higher doses per fraction. Objective: To assess the treatment efficacy and late complications of HDR ICBT with 9 Gy per fraction in two fractions. Materials and Methods: This is a prospective institutional study in Southern India carried on from $1^{st}$ June 2012 to $31^{st}$ July 2014. In this period, 76 patients of cervical cancer satisfying our inclusion criteria were treated with concurrent chemo-radiation following ICBT with 9 Gy per fraction in two fractions, five to seven days apart. Results: The median follow-up period in the study was 24 months (range 10.6 - 31.2 months). The 2 year actuarial local control rate, disease-free survival and overall survival were 88.1%, 84.2% and 81.8% respectively. Although 38.2% patients suffered from late toxicity, only 3 patients had grade III late toxicity. Conclusions: In our experience, HDR brachytherapy with 9 Gy per fraction in two fractions is an effective dose fractionation for the treatment of cervical cancer with acceptable toxicity.

• Journal of Yeungnam Medical Science
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• 제17권2호
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• pp.123-128
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• 2000

본 연구에서 인체공학적으로 개선된 새로운 2-채널 고선량을 근접치료용 적용구(Shin's Applicator)를 개발하였으며, 기존의 단일 선원 근접치료 적용구와 비교하여 질벽에 더 균등한 방사선치료가 가능하고 방광과 직장선량이 적어 근접치료 후 발생할 수 있는 부작용이 감소될 가능성을 확인하였다. 임상적으로 Shin's Applicator는 자궁 경부암이나 자궁 체부암의 수술 후 국소재발이나, 절강에 발생한 다발설 악성종양을 효과적으로 치료하는 데 유용하게 사용될 수 있을 뿐 만 아니라, 방사선 치료 후 흔히 나타나는 질강의 협착을 예방할 수 있는 질 확장기(vaginal dilator)로도 사용 가능하였다. 이상의 결과에서 Shin's Applicator는 부인과 종양환자들의 방사선치료 뿐만 아니라 치료 후 삶의 질의 개선에도 크게 기여할 것으로 생각되었다.

• 한국의학물리학회지:의학물리
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• 제32권2호
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• pp.25-39
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• 2021

Brachytherapy, along with external beam radiation therapy (EBRT), is an essential and effective radiation treatment process. In brachytherapy, in contrast to EBRT, the radiation source is radioisotopes. Because these isotopes can be positioned inside or near the tumor, it is possible to protect other organs around the tumor while delivering an extremely high-dose of treatment to the tumor. Brachytherapy has a long history of more than 100 years. In the early 1900s, the radioisotopes used for brachytherapy were only radium or radon isotopes extracted from nature. Over time, however, various radioisotopes have been artificially produced. As radioisotopes have high radioactivity and miniature size, the application of brachytherapy has expanded to high-dose-rate brachytherapy. Recently, advanced treatment techniques used in EBRT, such as image guidance and intensity modulation techniques, have been applied to brachytherapy. Three-dimensional images, such as ultrasound, computed tomography, magnetic resonance imaging, and positron emission tomography are used for accurate delineation of treatment targets and normal organs. Intensity-modulated brachytherapy is anticipated to be performed in the near future, and it is anticipated that the treatment outcomes of applicable cancers will be greatly improved by this treatment's excellent dose delivery characteristics.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제28권5호
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• pp.470-476
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• 2006

Low-dose rate brachytherapy(LDR) has been effective modality for treatment of oral cancer. But the disadvantage of LDR is radioexposure of medical staff. To overcome this problem, high dose rate(HDR) brachytherapy has been developed. Our study evaluates the outcomes of patients with tongue cancer as treated by HDR brachytherapy. Between 2002 and 2005, eight patients with carcinoma of the tongue were treated with HDR brachytherapy. Five patients had AJCC stage I or II disease and the remaining three patients had AJCC stage III or IV. The male-to-female ratio was 2:6 and the mean age was 60.1 years (range: 21-80 years).The median follow-up time was 23.8 months (range: 7-55 months). There was no local failure until now. Three patients showed some complications. Two patients showed soft tissue necrosis. There was no bone sequela in all cases. Our experience in treating tongue cancer with HDR brachytherapy is encouraging, because it gave a satisfactory local control. Prospective studies are necessary to delineate the optimum indication for this treatment modality and long-term outcome.

• 대한두경부종양학회지
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• 제7권1호
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• pp.3-9
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• 1991

Brachytherapy is a method of radiotherapy in advantage to achieve better local control with minimum radiation toxicity in comparison with external irradiation because radiation dose is distributed according to the inverse square low of gamma-ray emitted from the implanted sources. The main characteristics of brachytherapy are delivering of higher dose to target volume shortening of total treatment period and sparing of normal tissue. Recent development of iridium ribbons for low dose rate implant provides improvement of technology of brachytherapy in terms of safety and efficiency. High dose rate method. on the other hand, is effective to avoid unnecessary expoure of medical personnel.

• 대한방사선치료학회지
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• 제10권1호
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• pp.30-44
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• 1998

Accurate delivery of doses using a high dose rate(HDR) brachytherapy, remote afterloading system(RALS) depends on knowing the strength of the radioactive source at the time of treatment, the precision and consistency of the timer, and the ability of the unit to position the source at the proper dwell location along the applicator. Periodic Quality Assurance(QA) on HDR machines is a part of the standard protocol of any user. The safety of the patient & staff, positional accuracy, temporal accuracy, and dose delivery accuracy are periodically(weekly, quarterly, monthly) estimated using HDR source(Ir-192), treatment planning devices, measurement devices, and overall treatment devices with regard to treatment delivery. The overall measurement results are estimated successfully and assessed its clinical significance. As a result, our HDR brachytherapy units has been very accurate until now. The QA program protocol permits routine clinical use and provides a high confidence level in the accurate operation of HDR units. Therefore, regular QA of HDR brachytherapy is essential for successful treatment.

• Radiation Oncology Journal
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• 제4권2호
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• pp.183-186
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• 1986

고선량율을 이용한 자궁강내 치료시 정확하고 신속한 계산을 위하여 저자들은 개인용 컴퓨터를 이용하여 기준점의 선량분포 및 방사선조사 시간을 간편하게 계산할 수 있는 software를 개발하였다. 치료 계획용 software를 이용하여 짧은 시간내에 선량 분포 및 조사시간을 용이하고 정확하게 계산할 수 있으며, 고선량을 자궁경부암 임상적응에 효과적으로 이용할 수 있어서 보고한다.

• Radiation Oncology Journal
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• 제14권2호
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• pp.123-128
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• 1996

목적 : 악성 종양으로 인해 기도 폐쇄가 온 환자들을 저선량 및 고선량으로 내기관지 근접 치료하였을 경우의 대중치료 효과, 생존율 및 병발증을 비교 검토한다. 대상 및 방법 : 1988년 10월부터 1992년 6월까지 저선량 방법으로 21명, 1992년 8월부터 1994년 4월까지 고선량 방법으로 22명, 총 43명의 환자들에게 내기관지 근접치료를 시행하였다. 총 91회의 치료시, 모두 Fluorocopy하에서 굴절성 Fiberoptlc 내시경을 이용하였으며, 저선량 방법의 21회는 15-30 Gy를 0.75 cm 원경에, 고선량 방법의 64회는 5-7.5 Gy를 Ir-192 선원으로부터 1 Cm 원경에 각각 투사하였다. 결과 : 주관적 및 객관적 치료효과의 분석은 임상재진시 나타난 환자의 증상, 흥부 방사선 사진 및 흥부 단층촬영의 결과로 이루어졌다. 저산량으로 치료한 21명 중 15명의 환자와 고선량으로 치료한 22명 중 19명의 환자들이 주관적 치료효과가 있었음을 보였고, 8명의 저선량 환자와 10명의 고선량 환자가 흥부 방사선 사진과 단층 촬영상에서 객관적 효과가 있었음을 나타냈다. 결론 : 저선량 및 고선량 방사선에 의해 근접치료의 기술은 비교적 간단하며 환자가 별다른 후유증 없이 치료를 잘 받아 드리는 편이다. 이 치료 방법은 여생이 얼마 남지 않은 말기 폐암환자에게 내기관지 협착 내지는 폐쇄가 왔을 때 기관지의 공기소통을 원활히 증진시켜주는 대증치료 방법 이다.

• 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.