유방촬영 시 타겟/필터별 평균유선선량 환산인자 도출 = Derivation of the Mean Glandular Dose Conversion Factors for each Target /Filter in Mammography

다국어 초록 (Multilingual Abstract)

As the incidence of breast cancer in Korea increases, mammography usage is alsoincreasing. Mean glandular dose (MGD) is used to manage radiation dose in mammography. The MGDis calculated using the MGD conversion factor and measurable radiation quantities. The previouslydeveloped MGD conversion factors require half value layer (HVL) that is difficult to measure in medicalinstitutions when used. Therefore, the object of this study is to derive the MGD conversion factor usingexamination parameter that is easy to obtain, such as tube voltage. In this study, the X-ray spectra of themammography device for each target /filter were calculated to derive the MGD conversion factors. Thebreast computational phantom and the exposure situation in mammography were simulated. The MGDconversion factors were derived using the MCNP6 code, and compared with the previously developedMGD conversion factors to verify the derived MGD conversion factors. In the X-ray spectra for eachtarget/filter derived in this study, the mean energy was high in the order of W/Rh, Mo/Rh, and Mo/Mo atthe same tube voltage. As a result of comparing under the same parameters, the MGD conversion factorswere the highest at W/Rh, followed by Mo/Rh and Mo/Mo. When Mo/Rh and Mo/Mo were compared,the MGD conversion factors of Mo/Rh were higher in the all tube voltage. For all targets /filters, theMGD conversion factors increased as the tube voltage increased at the same glandularity, and theMGD conversion factors decreased as the compressed breast thickness increased. Compared to theMGD conversion factors of Dance and Wu, the differences were 8.9% and 6.8%, respectively. The MGDconversion factors developed in this study will contribute to the reduction of radiation doses resultingfrom mammography through use in managing radiation doses resulting from mammography at medicalinstitutions that are difficult to measure HVL.

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