ABSTRACT
Proton therapy is excellent in sparing normal organs due to the Bragg peak property of proton. However, the precise determination of proton range in treatment plans relies greatly on the accurate reconstruction of proton stopping power ratio from patient's simulation image. Current standard practice of proton range estimation requires calibration from the Hounsfield units of X-ray CT to proton stopping power ratio, inheriting the intrinsic uncertainty in the conversation from electron density to proton stopping power ratio. Therefore, different structures and concepts of proton radiography and proton computed tomography have been proposed by developers to achieve higher accuracy in proton range estimation. In this chapter, physics of proton interactions and proton imaging reconstruction are introduced. Furthermore, a brief review of the history of proton radiography and proton computed tomography, as well as a discussion of the frontier technologies of proton imaging is presented.
