Photogrammetric measurement of patients in radiotherapy
The correct positioning of the patient is an important demand in radiotherapy. Optical measurements seem appropriate, but special requirements of speed and accuracy must be met. A new photogrammetric system that captures patient surface data in real-time is introduced. It allows reproducible patient set-up, and monitors the patient's position during irradiation even when the patient is moving. It consists of two cameras and one projector and is based on the photogrammetric evaluation of stereo image pairs by projecting white light fringes onto the patient's body. The raw data of the 3D measurement is a sequence of point clouds. It can be evaluated together with other data modes common in radiotherapy for diagnosis and treatment planning. The system can be used as an additional verification tool for the correct positioning of the patient, and completely new applications emerge.
radiotherapy stereo tracking 3d positioning surface measurement medical system gray-code fringe projection visualisation