Dosimetry measurements with an intra-operative x-ray device Eaton, D. J., & Duck, S. (2010). Dosimetry measurements with an intra- operative x-ray device. Physics in medicine and biology, 55(12), N359. Chairman: Shih-Jhong Chen Presenter ： Cheng-bang Shih Adviser: ： Dr.Yi-Chun Du Date:

生醫系統整合實驗室 Integrated Biomedical System Laboratory Introduction Materials and methods Results Conclusion 2 Outline

生醫系統整合實驗室 Integrated Biomedical System Laboratory Introduction 3

生醫系統整合實驗室 Integrated Biomedical System Laboratory TARGIT, it uses a compact mobile x-ray unit, the Carl Zeiss INTRABEAM system, to deliver radiation from inside the tumour cavity. The device accelerates electrons to a maximum energy of 50 keV. Introduction 4

生醫系統整合實驗室 Integrated Biomedical System Laboratory For breast treatments is a solid spherical applicator is attached to the probe Introduction 5

生醫系統整合實驗室 Integrated Biomedical System Laboratory Aim of this study: – measure dosimetric data required by the IPEMB code of practice for the source with applicators attached. – compare the dosimetry of the INTRABEAM system to a superficial therapy x-ray unit in our centre. Introduction 6

生醫系統整合實驗室 Integrated Biomedical System Laboratory Materials and methods 7

生醫系統整合實驗室 Integrated Biomedical System Laboratory HVL Applicators with diameters of 3.0 cm and below have a metal sheath around the inside surface of this channel Ionization chamber was positioned 1.0 m from the x-ray source and a 1.5 mm thick lead sheet with 4 cm aperture in the centre was placed equidistant between the source and chamber. Materials and methods 8

生醫系統整合實驗室 Integrated Biomedical System Laboratory Determination of N K An applicator size of 1.5 cm. A cone size of 4.0 cm diameter with the Therapax 3. The end of the cone or applicator was positioned approximately 3 cm. without moving the x-ray source. Materials and methods 9

生醫系統整合實驗室 Integrated Biomedical System Laboratory Determination of k ch Materials and methods 10 M phan = chamber reading in a full scatter phantom corrected to standard temperature and pressure (1) (2) (3) B w = the backscatter factor M air = the chamber reading in air corrected to standard temperature and pressure

生醫系統整合實驗室 Integrated Biomedical System Laboratory Depth dose curves Materials and methods 11

生醫系統整合實驗室 Integrated Biomedical System Laboratory Results 12

生醫系統整合實驗室 Integrated Biomedical System Laboratory HVL Results 13

生醫系統整合實驗室 Integrated Biomedical System Laboratory Determination of NK Results 14

生醫系統整合實驗室 Integrated Biomedical System Laboratory Determination of k ch Results 15

生醫系統整合實驗室 Integrated Biomedical System Laboratory Depth dose curves Results 16

生醫系統整合實驗室 Integrated Biomedical System Laboratory Conclusion 17

生醫系統整合實驗室 Integrated Biomedical System Laboratory This study has described aspects of the dosimetry of the system with the spherical applicators used clinically for breast treatments. This study reduces the technical limitations in these measurements. Conclusion 18

生醫系統整合實驗室 Integrated Biomedical System Laboratory Thank you for your attention! 19