Journal: Journal of Applied Clinical Medical Physics

Article Title: Characteristics of breathing‐adapted gating using surface guidance for use in particle therapy: A phantom‐based end‐to‐end test from CT simulation to dose delivery

doi: 10.1002/acm2.14249

Figure Lengend Snippet: Left images show the different FOVs of the configured camera pods in the TPS (right, left, and middle pod) displaying the body region (black circle on the abdomen) needed for gating. Right images illustrate the real FOVs captured by AlignRT. Note that the tool is able to show the shadow caused by the patient, setup devices, and beam nozzle (white arrows). FOV, field of view; TPS, treatment planning system.

Article Snippet: These strategies include (i) expanding the internal margin of the target volume using the internal target volume (ITV) concept, , (ii) utilizing abdominal compression to restrict the tumor motion (e.g., in liver treatments), (iii) employing breath‐hold methods, , (iv) implementing tumor tracking, , and (v) using breathing‐adapted gating approaches to attempt tracking the patient breathing, and irradiating the tumor target during specific breathing phases., , , , , , For the latter, four‐dimensional computed tomography (4DCT) is used to reconstruct images at specific breathing phases based on either amplitude or phase., , , , Different respiratory monitoring systems (RMSs) are used for both 4DCT imaging and gating, including pressure sensors, skin‐surface camera systems, radiofrequency‐based systems and fiducial markers in combination with image‐guided RT., , , , , At Heidelberg Ion Beam Therapy Center (HIT), three optical surface‐guided RT (SGRT) systems, the AlignRT, SimRT, and GateRT (VisionRT Ltd, London, United Kingdom) have been installed between 2019 and 2021: (i) AlignRT and GateRT at the ion beam gantry treatment room, and (ii) SimRT at a CT scanner in the radiation oncology department.

Techniques: