ABSTRACT
Modern SGRT technology has witnessed a rapid and widespread adoption in the radiation therapy clinic. SGRT provides real-time position information during simulation, patient setup, and treatment delivery including respiratory-correlated techniques. The versatility of the technology holds the promise of creating broad quality and safety benefits in the clinic. This chapter begins with a historical review of optical-based approaches to localization that lead to the development of modern SGRT, from early efforts at verifying patient setup and monitoring patient position with television cameras, to modern real-time in-room guidance and continual localization with advanced 3D imaging and processing technology. The theories and basic principles underpinning current surface imaging technologies are described, including calibration and registration algorithms. The aim of this chapter is to provide the reader with a thorough appreciation of the history and trajectory of SGRT technologies, including their role in the context of modern IGRT, so that the diverse applications of SGRT in the clinic can be fully appreciated.
