1
|
Karger CP, Elter A, Dorsch S, Mann P, Pappas E, Oldham M. Validation of complex radiotherapy techniques using polymer gel dosimetry. Phys Med Biol 2024; 69:06TR01. [PMID: 38330494 DOI: 10.1088/1361-6560/ad278f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 02/08/2024] [Indexed: 02/10/2024]
Abstract
Modern radiotherapy delivers highly conformal dose distributions to irregularly shaped target volumes while sparing the surrounding normal tissue. Due to the complex planning and delivery techniques, dose verification and validation of the whole treatment workflow by end-to-end tests became much more important and polymer gel dosimeters are one of the few possibilities to capture the delivered dose distribution in 3D. The basic principles and formulations of gel dosimetry and its evaluation methods are described and the available studies validating device-specific geometrical parameters as well as the dose delivery by advanced radiotherapy techniques, such as 3D-CRT/IMRT and stereotactic radiosurgery treatments, the treatment of moving targets, online-adaptive magnetic resonance-guided radiotherapy as well as proton and ion beam treatments, are reviewed. The present status and limitations as well as future challenges of polymer gel dosimetry for the validation of complex radiotherapy techniques are discussed.
Collapse
Affiliation(s)
- Christian P Karger
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
- National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
| | - Alina Elter
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
- National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
- Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, D-69120 Heidelberg, Germany
| | - Stefan Dorsch
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
- National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
| | - Philipp Mann
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
- National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
| | - Evangelos Pappas
- Radiology & Radiotherapy Sector, Department of Biomedical Sciences, University of West Attica, Athens, Greece
| | - Mark Oldham
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC, United States of America
| |
Collapse
|
2
|
Chemical Overview of Gel Dosimetry Systems: A Comprehensive Review. Gels 2022; 8:gels8100663. [PMID: 36286165 PMCID: PMC9601373 DOI: 10.3390/gels8100663] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 10/10/2022] [Accepted: 10/12/2022] [Indexed: 11/17/2022] Open
Abstract
Advances in radiotherapy technology during the last 25 years have significantly improved both dose conformation to tumors and the preservation of healthy tissues, achieving almost real-time feedback by means of high-precision treatments and theranostics. Owing to this, developing high-performance systems capable of coping with the challenging requirements of modern ionizing radiation is a key issue to overcome the limitations of traditional dosimeters. In this regard, a deep understanding of the physicochemical basis of gel dosimetry, as one of the most promising tools for the evaluation of 3D high-spatial-resolution dose distributions, represents the starting point for developing new and innovative systems. This review aims to contribute thorough descriptions of the chemical processes and interactions that condition gel dosimetry outputs, often phenomenologically addressed, and particularly formulations reported since 2017.
Collapse
|
3
|
Elter A, Rippke C, Johnen W, Mann P, Hellwich E, Schwahofer A, Dorsch S, Buchele C, Klüter S, Karger CP. End-to-end test for fractionated online adaptive MR-guided radiotherapy using a deformable anthropomorphic pelvis phantom. Phys Med Biol 2021; 66. [PMID: 34845991 DOI: 10.1088/1361-6560/ac3e0c] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 11/29/2021] [Indexed: 11/12/2022]
Abstract
Objective.In MR-guided radiotherapy (MRgRT) for prostate cancer treatments inter-fractional anatomy changes such as bladder and rectum fillings may be corrected by an online adaption of the treatment plan. To clinically implement such complex treatment procedures, however, specific end-to-end tests are required that are able to validate the overall accuracy of all treatment steps from pre-treatment imaging to dose delivery.Approach.In this study, an end-to-end test of a fractionated and online adapted MRgRT prostate irradiation was performed using the so-called ADAM-PETer phantom. The phantom was adapted to perform 3D polymer gel (PG) dosimetry in the prostate and rectum. Furthermore, thermoluminescence detectors (TLDs) were placed at the center and on the surface of the prostate for additional dose measurements as well as for an external dose renormalization of the PG. For the end-to-end test, a total of five online adapted irradiations were applied in sequence with different bladder and rectum fillings, respectively.Main results.A good agreement of measured and planned dose was found represented by highγ-index passing rates (3%/3mmcriterion) of the PG evaluation of98.9%in the prostate and93.7%in the rectum. TLDs used for PG renormalization at the center of the prostate showed a deviation of-2.3%.Significance.The presented end-to-end test, which allows for 3D dose verification in the prostate and rectum, demonstrates the feasibility and accuracy of fractionated and online-adapted prostate irradiations in presence of inter-fractional anatomy changes. Such tests are of high clinical importance for the commissioning of new image-guided treatment procedures such as online adaptive MRgRT.
Collapse
Affiliation(s)
- A Elter
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Faculty of Physics and Astronomy, Heidelberg University, Heidelberg, Germany.,National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
| | - C Rippke
- National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany.,Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany.,Medical Faculty, Heidelberg University, Heidelberg, Germany
| | - W Johnen
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
| | - P Mann
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
| | - E Hellwich
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
| | - A Schwahofer
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
| | - S Dorsch
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
| | - C Buchele
- National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany.,Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany.,Medical Faculty, Heidelberg University, Heidelberg, Germany
| | - S Klüter
- National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany.,Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany
| | - C P Karger
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
| |
Collapse
|
4
|
Marot M, Elter A, Mann P, Schwahofer A, Lang C, Johnen W, Körber SA, Beuthien-Baumann B, Gillmann C. Technical Note: On the feasibility of performing dosimetry in target and organ at risk using polymer dosimetry gel and thermoluminescence detectors in an anthropomorphic, deformable, and multimodal pelvis phantom. Med Phys 2021; 48:5501-5510. [PMID: 34260079 DOI: 10.1002/mp.15096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 05/28/2021] [Accepted: 06/25/2021] [Indexed: 11/08/2022] Open
Abstract
OBJECTIVE To assess the feasibility of performing dose measurements in the target (prostate) and an adjacent organ at risk (rectum) using polymer dosimetry gel and thermoluminescence detectors (TLDs) in an anthropomorphic, deformable, and multimodal pelvis phantom (ADAM PETer). METHODS The 3D printed prostate organ surrogate of the ADAM PETer phantom was filled with polymer dosimetry gel. Nine TLD600 (LiF:Mg,Ti) were installed in 3 × 3 rows on a specifically designed 3D-printed TLD holder. The TLD holder was inserted into the rectum at the level of the prostate and fixed by a partially inflated endorectal balloon. Computed tomography (CT) images were taken and treatment planning was performed. A prescribed dose of 4.5 Gy was delivered to the planning target volume (PTV). The doses measured by the dosimetry gel in the prostate and the TLDs in the rectum ("measured dose") were compared to the doses calculated by the treatment planning system ("planned dose") on a voxel-by-voxel basis. RESULTS In the prostate organ surrogate, the 3D-γ-index was 97.7% for the 3% dose difference and 3 mm distance to agreement criterium. In the center of the prostate organ surrogate, measured and planned doses showed only minor deviations (<0.1 Gy, corresponding to a percentage error of 2.22%). On the edges of the prostate, slight differences between planned and measured doses were detected with a maximum deviation of 0.24 Gy, corresponding to 5.3% of the prescribed dose. The difference between planned and measured doses in the TLDs was on average 0.08 Gy (range: 0.02-0.21 Gy), corresponding to 1.78% of the prescribed dose (range: 0.44%-4.67%). CONCLUSIONS The present study demonstrates the feasibility of using polymer dosimetry gel and TLDs for 3D and 1D dose measurements in the prostate and the rectum organ surrogates in an anthropomorphic, deformable and multimodal phantom. The described methodology might offer new perspectives for end-to-end tests in image-guided adaptive radiotherapy workflows.
Collapse
Affiliation(s)
- Mathieu Marot
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Faculty of Medicine, University of Heidelberg, Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Alina Elter
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Faculty of Physics and Astronomy, University of Heidelberg, Heidelberg, Germany
| | - Philipp Mann
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,HQ-Imaging GmbH, Heidelberg, Germany
| | - Andrea Schwahofer
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Clemens Lang
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Wibke Johnen
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Stefan A Körber
- Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany
| | - Bettina Beuthien-Baumann
- Department of Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,National Center for Tumor Diseases (NCT), Heidelberg, Germany
| | - Clarissa Gillmann
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,National Center for Tumor Diseases (NCT), Heidelberg, Germany
| |
Collapse
|