ESTRO 2025 - Abstract Book

S2608

Physics - Detectors, dose measurement and phantoms

ESTRO 2025

Figure 2: Table summary of t rise at various irradiation conditions.

Conclusion: Our findings revealed that t RFK is independent of beam’s energy, nominal beam intensity set and spot dose. However, t rise is dependent on the beam intensity and needs to be validated carefully for each beam intensity. These insights are instrumental for developing beam delivery time model for DDCS which plays an important role in optimizing of beam current and overall delivery time.

Keywords: Proton Therapy, Dose Driven Continuous Scanning

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Mini-Oral MiniADAM: from a lung-equivalent compressible material to a miniaturized breathing phantom for theranostic applications Immacolata Vanore 1 , Fulvio Ratto 2 , Andrea Profili 3 , Livia Marrazzo 1,4 , Lucia Cavigli 2 , Michaela Servi 3 , Yary Volpe 3 , Silvia Calusi 4 , Riccardo Lisci 5 , Cosimo Nardi 1 , Giacomo Insero 1 , Giovanni Romano 1 , Alberto Dalla Mora 6 , Laura Di Sieno 6 , Stefania Pallotta 1,4 1 Department of Experimental and Clinical Biomedical Sciences “Mario Serio”, University of Florence, Florence, Italy. 2 Italian National Research Council IFAC-CNR, Institute of Applied Physics, Sesto Fiorentino, Italy. 3 Department of Industrial Engineering, University of Florence, Florence, Italy. 4 Medical Physics Unit, Azienda Ospedaliero Universitaria Careggi, Florence, Italy. 5 Department of Agricultural, Food and Forestry System, University of Florence, Florence, Italy. 6 Department of Physics, Politecnico di Milano, Milan, Italy Purpose/Objective: The field of radiation therapy is continuously advancing in targeting malignant tissues. However, radiotherapy treatment for lesions in moving organs, such as the lungs, remains a significant challenge. Furthermore, the development of phantoms capable of accurately simulating the architecture and morphological features of healthy and diseased lungs is still limited. This study, evolved in the frame of PRIN 2022 ALPHA project, aims to develop a multi-purpose lung phantom prototype that replicates both the respiratory dynamics and the morphological features observed in clinical radiological imaging (CT and MRI) of lung parenchyma. Material/Methods: The lung-equivalent material was created using polydimethylsiloxane (PDMS), combining micron-sized hydrogel particle emulsions with PDMS sponges featuring sub-millimeter pores [4]. The resulting material was characterized using CT imaging to evaluate Hounsfield Units (HU) and MRI to measure longitudinal relaxation time (T1), allowing comparisons with human lung parenchyma. Long-term reproducibility was assessed through qualitative and quantitative imaging. To simulate realistic respiratory dynamics, an ad-hoc phantom was developed. 4D-CT scans of the breathing phantom were acquired and analyzed.