SGRT

SGRT imaging systems use cameras installed in the treatment room that emit infrared light (and therefore without additional ionizing radiation), allows real-time monitoring of the patient’s position, comparing the patient’s surface at the time of the treatment with the planned one, thus reducing intrafraction errors

Surface Guided Radiotherapy (SGRT) is a relatively recent technology that was added to existing image guidance systems. The use of SGRT imaging systems, which use cameras installed in the treatment room that emit infrared light (and therefore without additional ionizing radiation), allows for real-time monitoring of the patient’s position, comparing the patient’s surface at the time of the treatment with the planned one, thus reducing intrafraction errors. This is possible through the principle of triangulation, that can reconstruct a three-dimensional representation of the patient’s surface that is related to the treatment coordinate system. SGRT also reduces interfraction errors, since during delivery any inconsistencies between the actual live surface and the reference surface can be detected in real-time and the beam is interrupted whenever there is a movement above a defined tolerance.

SGRT has been adopted into clinical practice in many radiotherapy institutions for patient setup, monitoring and gating. The main advantage of SGRT is to assess patient positioning in real-time without using ionising radiation. The large field-of-view (FOV) for patient setup provides information about the patient’s anatomical topography including rotations. SGRT has been reported to either improve patient’s positioning while improving efficiency. Due to increased information about the patient position and the standardised workflows, SGRT has the potential to greatly impact the quality and safety of radiation treatments.