ESTRO 2025 - Abstract Book

S3160

Physics - Inter-fraction motion management and offline adaptive radiotherapy

ESTRO 2025

Conclusion: HU threshold is a key parameter when SGRT uses BODY for patient positioning. It was found that a threshold of - 714±6HU is the optimal to create the BODY when RayStation is used as TPS and Exactrac Dynamic as SGRT system for patient positioning.

Keywords: SGRT, Raystation, Exactrac Dynamic

References: [1]

ExacTrac Dynamic [online] Brainlab AG. [Consultation: 22 jun 2024] <

https://www.brainlab.com/es/productos-de-radiocirugia/exactrac/ >. [2]

RayStation [online] RaySearch Laboratories. [Consultation: 22 jun 2024] <

https://www.raysearchlabs.com/raystation/ >.

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Digital Poster BODY optimization with Elements TPS for Brainlab Exactrac Dynamic Surface Guided Radiotherapy system positioning Ana Reguilón Martín 1 , Rodrigo Astudillo Olalla 2 , Rosa Fabregat Borras 1 , Marina Gutiérrez Ruiz 1 , Noelia Suarez Álvarez 1 , Jorge Alonso Muriedas 3 , Javier Uzquiza López 1 , Andrea Ropero Real 1 , Jose Andrés Vázquez Rodriguez 1 , Uriel A. Corro Verde 4 , Frandeina Pinto Guevara 4 , Mara García Lamela 4 , Francisco J. Olloqui Urroz 4 , María Teresa Pacheco Baldor 1 1 Radiofíscia, Hospital Universitario Marqués de Valdecilla, Santander, Spain. 2 Radiofísica y Protección Radiológica, Hospital Universitario de Navarra, Pamplona, Spain. 3 Radiofísica y Protección Radiológica, Hospital Universitario de Cruces, Baracaldo, Spain. 4 Oncología Radioterápica, Hospital Universitario Marqués de Valdecilla, Santander, Spain Purpose/Objective: Patient positioning plays a crucial role in the quality and safety of patients during radiotherapy treatments. Surface Guided Radiotherapy (SGRT) is a type of Image Guided Radiotherapy (IGRT) that facilitates patient positioning and motion control during treatments. They utilize the detection of the patient’s surface through non ionizing radiation that is projected on and reflected from that surface. Exactrac Dynamic from Brainlab®™ is an IGRT system composed of a 4D thermal camera (which combines structured light and thermal radiation) and a stereoscopic X-ray system. Throughout this study, the aim is to determine the optimal threshold of Hounsfield Units (HU) for generating the BODY contours of patients in Elements® (Brainlab), thereby optimizing its SGRT system compared to the X-ray system.