The following partners contribute to the project as part of the consortium:

As the national metrology institute of the Netherlands, VSL develops and maintains primary dosimetry standards and measurement techniques for existing and advanced radiotherapy applications. Moreover, VSL has ample experience in applying primary standards on-site in clinical facilities. Based on these capabilities, VSL makes measurements in hospitals, companies and other laboratories directly traceable to international standards. This is done by research projects, the development of new measurement set-ups, measurement services (such as calibrations), participation in the development of dosimetry protocols used by medical physicists and training courses.

Dr. Jacco de Pooter, project coordinator of the MRgRT project: “MR guided radiotherapy (MRgRT) requires considerable advancements in primary standardisation and the development of dosimetry protocols. The focus of research at VSL is on advanced radiotherapy modalities and VSL has already developed considerable experience in previous EMRP projects. Therefore, being part of the Metrology for MRgRT project as a coordinator is a logical choice.”

“MRgRT is one of the two major developments in today’s radiotherapy (the other being proton therapy). It will lead to patient treatment in which real-time image information will guide the dose optimisation and delivery. This is not possible with current radiotherapy modalities, leading to unnecessarily large safety margins around target volumes.”

DTU is the Technical University of Denmark, Department of Health Technology. It operates a medical accelerator dosimetry laboratory and has status as Designated Institute within the field of ionizing radiation. DTU carries out research on MR-linac dosimetry in close collaboration with two Danish university hospitals with MR-linacs. DTU’s dosimetry research is well aligned with the Danish hospitals through the Danish Comprehensive Cancer Center (DCCC). DTU has worked extensively with solid state dosimetry (fiber-coupled scintillators and alanine) in the context of small-field dosimetry and treatment plan verification for radiotherapy.

Website DTU

The Physikalisch-Technische Bundesanstalt (PTB), Germany’s national metrology institute, is a scientific and technical higher federal authority falling under the competence of the Federal Ministry for Economic Affairs and Energy. PTB consists of 9 scientific-technical divisions, including Ionising Radiation.

Dr. Ralf-Peter Kapsch, head of the high-energy photon and electron radiation working group at PTB: “It is expected that an increasing number of MRgRT facilities will be installed in Germany over the next few years offering new possibilities for cancer treatment. This will also lead to new challenges for medical physicists responsible for the quality assurance and the correct irradiation of patients. PTB is amenable to law for the unity of measurements in medicine (in Germany) and for the promotion of the international harmonisation of metrology. For these reasons PTB is very interested in the development of an internationally harmonised guideline for medical physicists, a Code of Practice, applicable in MRgRT, which is one of the main goals of this project.”

“Based on the increasing precision in application, radiotherapy relies more and more on accurate imaging of the patient and the tumour to increase the cure rate. This also implies that the existing high spatial dose conformity with the tumour needs to be adaptable to temporal changes. Image guided, and especially MR guided radiotherapy allows the next big developmental step forward in reaching this aim.”

The National Physical Laboratory (NPL) is the national measurements institute of the UK. It maintains the national measurement standards, including the radiation dosimetry standards.

Dr. Simon Duane, Principal Research Scientist of NPL: “MR guided radiotherapy (MRgRT), an advanced technology for cancer treatment, combines a linear accelerator (linac) with a Magnetic Resonance Imaging (MRI) scanner. The combination of these two machines is important because allows real-time tumour visualization during treatment, in contrast to current X-ray imaging techniques.  This provides high accuracy of soft tissue localization of either the tumour or the organs at risk, while completely avoiding the radiation dose associated with X-ray CT. MRgRT will change the way that the patients have been treated so far. It will potentially improve real-time adaptive planning based on high contrast moving visual images of the change of the tumour characteristics.”

The German Cancer Research Center (DKFZ) has been involved in the development and clinical implementation of several new radiotherapy (RT) techniques and modalities (e.g. intensity modulated RT, and ion beam RT). In line with this development, DKFZ is now strongly involved in the clinical development and implementation of MRgXT. Recently, clinical treatments on an MR-Linac device were started. The DKFZ has an internationally well-recognized research program in the field of Medical Physics covering a wide spectrum of topics (including MRgPT). This especially includes advanced computational modelling and treatment planning, dosimetry and quality assurance. In this project, the DKFZ will contribute by performing output factor and relative dose profile measurements in small photon fields at a state-of-the-art MR-Linac (MRIdian, ViewRay, US) and by comparing the results with Monte Carlo calculations.

The Institute of Radiooncology – OncoRay of the HZDR (Helmholtz-Zentrum Dresden-Rossendorf) has been involved in translational research in the field of radiation oncology since more than a decade. Scientists specializing in medicine, physics, biology and IT work together to improve the treatment of cancer by administering radiation therapy that is biologically personalized and technically optimized.

The focus is on cross-disciplinary precision radiation medicine research to optimise proton therapy as high-precision treatment modality. In line with this research goal, HZDR has made major progress to integrate MRI and proton therapy. A first research prototype system for in-beam MRI was established at the static proton research beamline in 2018. Further in-beam MRI prototype systems are now under development at the pencil-beam scanning research beamline. There is a close collaboration with DKFZ on treatment planning for in-beam MRI based proton therapy.

The Department of Radiotherapy is part of the main research line Personalized Cancer Care of the UMC Utrecht Center for Image Sciences. The main research line of the department is MRI guided radiotherapy.

Prof. Dr. Bas Raaymakers, Professor Experimental Clinical Physics at the Department of Radiotherapy of UMC Utrecht: “In a longstanding, joint effort with Elekta and Philips, UMC Utrecht has designed and developed the hybrid MRI radiotherapy system. Currently we have two prototypes installed for technical research and a third system is being prepared for clinical introduction. We foresee much improved radiotherapy by offering MR imaging to the radiation oncologist during the radiation delivery.”

“The anatomical feedback from the MRI can be used to reconstruct exactly what has been done during the treatment. This knowledge can be used to optimise the remaining treatment fractions. Moreover, MRI enables live feedback for motion compensated radiation delivery and the possibility to work towards real-time plan adaptation. Together, this should lead to a more precise radiation delivery of moving tumours, implying better cure with less toxicity.”

“This project is a very good showcase of the joint efforts needed to bring dosimetry for a new system like this to the clinic. Additionally, it enables the development of new technology that might also be used in existing clinics.”

The University Clinic of Medical Radiation Physics at the Uni-Oldenburg (University of Oldenburg) has been involved in the development of multi-dimensional dose measurements techniques since the introduction of intensity modulated radiation therapy, while maintaining an intensive cooperation with the industry in detector development activities. With the clinical implementation of MRgXT, the research group is currently adopting the established physical and mathematical models for dose measurements in small fields to consider the influence of magnetic field on detector’s dose response.