Journal Article

GSI-2025-01090

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Real-time motion modeling and treatment verification for irregular motion in carbon ion therapy: a feasibility study

Galeone, C. (Corresponding author)GSI* ; Nakas, A. ; Donetti, M. ; Martire, M. C.GSI* ; Milian, F. M. ; Pella, A. ; Paganelli, C. ; Sacchi, R. ; Vignati, A. ; Durante, M.GSI* ; Baroni, G. ; Giordanengo, S. ; Graeff, C. (Last author)GSI*

2025
IOP Publ. Bristol

Please use a persistent id in citations: doi:10.1088/1361-6560/adf592  doi:10.15120/GSI-2025-01090

Abstract: Objective.Irregular motion impacts treatment accuracy and can be compensated by larger margins or online adaptive approaches. A seamless workflow for fast and accurate 4D-dose reconstruction allows dosimetric monitoring intra- and inter-fractionally, as a basis for adaptive therapy. This study presents a real-time, motion-adaptive framework that combines motion modeling and treatment verification, integrated into the dose delivery and monitoring systems to enable continuous assessment of the delivered 4D-dose.Approach.The framework includes a GPU-based analytical algorithm for real-time dose reconstruction in carbon ion therapy, interfaced with the dose delivery and optical tracking systems at the Centro Nazionale di Adroterapia Oncologica (CNAO). A motion model, driven by external surrogate tracking, generates a virtual CT every 150 ms, used for 4D-dose reconstruction with measured spot parameters. Planned and delivered doses are compared after each iso-energy slice. The framework was validated at CNAO using a geometric target and a 4D lung tumor phantom with a moving 2D ionization chamber array, under regular and irregular motion patterns.Main results.The framework successfully generated real-time CT images of the lung phantom, showing strong agreement with ground-truth images. Dose reconstructions were performed within inter-spill times during delivery, ensuring rapid assessment. Comparisons against detector measurements yielded an average gamma-index passing rate of 99% (3%/3 mm), confirming the accuracy of both the motion model and the integrated treatment verification system.Significance.This work presents the first real-time framework for carbon ion therapy, integrating motion modeling and dose reconstruction to handle irregular motion, fully embedded in a clinic-like setup.

Keyword(s): Heavy Ion Radiotherapy: methods (MeSH) ; Feasibility Studies (MeSH) ; Humans (MeSH) ; Movement (MeSH) ; Phantoms, Imaging (MeSH) ; Time Factors (MeSH) ; Radiotherapy Planning, Computer-Assisted: methods (MeSH) ; Radiotherapy Dosage (MeSH) ; Four-Dimensional Computed Tomography (MeSH) ; Lung Neoplasms: radiotherapy (MeSH) ; Lung Neoplasms: diagnostic imaging (MeSH) ; Lung Neoplasms: physiopathology (MeSH) ; adaptive therapy ; irregular motion ; motion model ; particle therapy ; real-time dose calculation

Note: Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence.

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Contributing Institute(s):

1. Biophysik (BIO)

Research Program(s):

1. 633 - Life Sciences – Building Blocks of Life: Structure and Function (POF4-633) (POF4-633)
2. RAPTOR - Real-time Adaptive Particle Therapy of Cancer (955956) (955956)
3. SUC-GSI-Darmstadt - Strategic university cooperation GSI-TU Darmstadt (SUC-GSI-DA) (SUC-GSI-DA)

Experiment(s):

1. External experiment at external facility/ no experiment at GSI (other)

Appears in the scientific report 2025

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Database coverage:
; ; ; BIOSIS Previews ; Biological Abstracts ; Clarivate Analytics Master Journal List ; Current Contents - Life Sciences ; Ebsco Academic Search ; Essential Science Indicators ; IF < 5 ; JCR ; National-Konsortium ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

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