The importance of 3D dosimetry

8th International Conference on 3D Radiation Dosimetry

Low, Daniel^1

UCLA Radiation Oncology, 200 Medical Plaza, Los Angeles

CA

90095, United States^1

关键词: Array measurements;    Dose distributions;    Image guided therapy;    Intensity modulated radiation therapy;    Medical physicists;    Multi-detector arrays;    Professional associations;    Radiographic films;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/573/1/012009/pdf
DOI  :  10.1088/1742-6596/573/1/012009

来源: IOP

【 摘 要 】

Radiation therapy has been getting progressively more complex for the past 20 years. Early radiation therapy techniques needed only basic dosimetry equipment; motorized water phantoms, ionization chambers, and basic radiographic film techniques. As intensity modulated radiation therapy and image guided therapy came into widespread practice, medical physicists were challenged with developing effective and efficient dose measurement techniques. The complex 3-dimensional (3D) nature of the dose distributions that were being delivered demanded the development of more quantitative and more thorough methods for dose measurement. The quality assurance vendors developed a wide array of multidetector arrays that have been enormously useful for measuring and characterizing dose distributions, and these have been made especially useful with the advent of 3D dose calculation systems based on the array measurements, as well as measurements made using film and portal imagers. Other vendors have been providing 3D calculations based on data from the linear accelerator or the record and verify system, providing thorough evaluation of the dose but lacking quality assurance (QA) of the dose delivery process, including machine calibration. The current state of 3D dosimetry is one of a state of flux. The vendors and professional associations are trying to determine the optimal balance between thorough QA, labor efficiency, and quantitation. This balance will take some time to reach, but a necessary component will be the 3D measurement and independent calculation of delivered radiation therapy dose distributions.