초록 ▼

방사선 치료에서 치료목적으로 부여하는 선량 외에 부가적으로 부여되는 선량의 다양한 경로에 대한 실험적, 전산적 연구를 진행하였다. 환자의 CT 촬영부터 치료를 위한 영상유도까지 치료과정 중 환자에게 부여되는 선량과 이에 따른 위험도를 분석하는 기술을 개발하였다. 유방암, 폐암, 간암, 췌장암 등 주요암종 및 새로이 방사선치료에 적용되는 암종에 대한 환자의 선량을 평가했으며, 3D-CRT, IMRT, VMAT, Cyberknife, Tomotherapy 등 대부분의 치료기법에 대하여 평가를 수행하였다. 환자에 부여된 직접 선량을 측정

방사선 치료에서 치료목적으로 부여하는 선량 외에 부가적으로 부여되는 선량의 다양한 경로에 대한 실험적, 전산적 연구를 진행하였다. 환자의 CT 촬영부터 치료를 위한 영상유도까지 치료과정 중 환자에게 부여되는 선량과 이에 따른 위험도를 분석하는 기술을 개발하였다. 유방암, 폐암, 간암, 췌장암 등 주요암종 및 새로이 방사선치료에 적용되는 암종에 대한 환자의 선량을 평가했으며, 3D-CRT, IMRT, VMAT, Cyberknife, Tomotherapy 등 대부분의 치료기법에 대하여 평가를 수행하였다. 환자에 부여된 직접 선량을 측정하기 위해 선량계를 고정하는 장비를 개발하여 직장암, 설암 환자 선량측정을 수행하였다.

Abstract ▼

Ⅳ. Results

Within 30 years 4,199 cases were analyzed for radiation incidence. The incidence of domestic and princess margret hospital were also analyzed.
The technique to increase a surface dose were studied. The calculated results compared with EBT film were agreed within 98% for 2D evalu

Ⅳ. Results

Within 30 years 4,199 cases were analyzed for radiation incidence. The incidence of domestic and princess margret hospital were also analyzed.
The technique to increase a surface dose were studied. The calculated results compared with EBT film were agreed within 98% for 2D evaluation. An accuracy for small field dose was evaluated for 1 to 3 cm field, monte carlo calculation results from iplan gave 1.4 difference in maximum. in IMRT comparison including spine case, it gave 1.5% difference in maximum
For dose evaluation of 2D simulator, dose measurement was done using ART phantom. dose calculation was studied using KTMAN-2 and MCNPX. The changes in image quality and dose were measured for various scanning conditions. These were compared with the result of MCNPX and we got good agreement within 3%. CT reconstruction techniques were stuided using MLEM and OSEM method for CTDI phantom and KTMAN-2. OSEM method gave 1,000 times faster than MLEM method. For CBCT image reconstruction, developed GP-BB algorithm gave 67% dose reduction. AEC mode was adopted in 4D CT acquisition we found that there was 20.83% advantage in pancrease cancer, 26.25% in liver cancer, 16.43% in lung cancer. in measurement study, there was 73.5% dose reduction in lung cancer, 29.8% dose reduction in liver cancer.
To improve the safety in radiation therapy, quality assurance program for Linear accelerator, virtual wedge, multi-leaf collimator, image devece. The analyzed results were supported using FMEA method for radiosurgery of lung cancer patient
The secondary dose and risk from scatter radiation for breast cancer, lung cancer, liver cancer, was measured using glass dosimeter and calculated with various treatment techniques.
The dose and risks from fluoroscopy and CBCT used for image guided radiotherapy were analyzed for radiosurgery patient of pancreas cancer, liver cancer, and lung cancer.
By adoption of shielding in CBCT scanning, dose reduction was measured using glass dosimeter, there were 90% dose reduction in brain scan, 70% dose reduction in chest scan, 70% dose reduction in pelvic scan. The dose and risks from MVCT used for verification of treatment position in tomotherapy were evaluated. The dose and risks from exactrac system used for image verification of treatment position during cyberknife radiosurgery were evaluate for brain, C-spine, T-spine, L-spine, and S-spine. The dose and risks from exactrac system used for image verification of treatment positioning with Novalis radiosurgery for brain cancer patients.
The measurement result in standard measurement condition using glass dosimeter used for in-vivo dose evaluation gave an accuracy of 3%. A rectal balloon was manufactured for measurement of dose in rectal wall, It was measured that there was accuracy of 1.7±2.7% in PMMA phantom, –1.2±2.7% in silicon phantom, and 2.7±4.4% in cancer patient. It was measured that there was accuracy of 3.7±3.1% in tung cancer patient even though large cavity is included.
An enough data for recommendation of patient dose to use a guideline in additional dose of radiation treatment procedures was supported. For CT examination, enough evaluation methods were suggested to get less than 60 mGy for brain scan, 20 mGy for abdomen scan. Also appropriate usage of radiation for radiation treatment related diagnostic device, CT, and 4DCT, image guided device, simulator, OBI, fluoroscope, CBCT, MVCT, treatment position verification, Linac-gram, EPID.