ICRU REPORT 97: MRI-Guided Radiation Therapy Using MRI-Linear Accelerators

Acharya S. Fischer-Valuck B.W. Kashani R. , et al (2016). “Online magnetic resonance image guided adaptive radiation therapy: First clinical applications,” Int. J. Radiat. Oncol. Biol. Phys. 94, 394–403. doi:10.1016/j.ijrobp.2015.10.015.

ACR (2015). Magnetic Resonance Imaging Quality Control Manual (American College of Radiology, Reston, VA).

ACR (2018). Phantom Test Guidance for Use of the Large MRI Phantom (American College of Radiology, Reston, VA).

ACR (2019). Large Phantom Testing: MRI (Revised 12-12-19) (American College of Radiology). https://accreditationsupport.acr.org/support/solutions/articles/11000061035-large-phantom-testing-mri-revised-12-12-19-.

ACR (2020). ACR Manual on MR Safety (American College of Radiology). https://www.acr.org/-/media/ACR/Files/Radiology-Safety/MR-Safety/Manual-on-MR-Safety.pdf.

Ahmad S.B. Sarfehnia A. Paudel M.R. , et al (2016). “Evaluation of a commercial MRI Linac based Monte Carlo dose calculation algorithm with GEANT4,” Med. Phys. 43, 894–907. doi:10.1118/1.4939808.

Alexander S.E. McNair H.A. Oelfke U. , et al (2022). “Prostate volume changes during extreme and moderately hypofractionated magnetic resonance image-guided radiotherapy,” Clin. Oncol. 34, e383–e391. doi:10.1016/j.clon.2022.03.022.

Almansour H. Afat S. Fritz V. , et al (2021). “Prospective image quality and lesion assessment in the setting of MR-guided radiation therapy of prostate cancer on an MR-linac at 1.5 T: A comparison to a standard 3 T MRI,” Cancers 13, 1533. doi:10.3390/cancers13071533.

Alnaghy S.J. Causer T. Roberts N. , et al (2020). “High resolution silicon array detector implementation in an inline MRI-linac,” Med. Phys. 47, 1920–1929. doi:10.1002/mp.14016.

Axford A. Dikaios N. Roberts D.A. Clark C.H. Evans P.M. (2021). “An end-to-end assessment on the accuracy of adaptive radiotherapy in an MR-linac,” Phys. Med. Biol. 66, 055021. doi:10.1088/1361-6560/abe053.

Bahig H. Yuan Y. Mohamed A.S.R. , et al (2018). “Magnetic resonance-based response assessment and dose adaptation in human papilloma virus positive tumors of the oropharynx treated with radiotherapy (MR-ADAPTOR): An R-IDEAL stage 2a-2b/Bayesian phase II trial,” Clin. Transl. Radiat. Oncol. 13, 19–23. doi:10.1016/j.ctro.2018.08.003.

Baldwin L.N. Wachowicz K. Thomas S.D. Rivest R. Fallone B.G. (2007). “Characterization, prediction, and correction of geometric distortion in 3 T MR images,” Med. Phys. 34, 388–399. doi:10.1118/1.2402331.

Bentzen S.M. Dörr W. Gahbauer R. , et al (2012). “Bioeffect modeling and equieffective dose concepts in radiation oncology–terminology, quantities and units,” Radiother. Oncol. 105, 266–268. doi:10.1016/j.radonc.2012.10.006.

Berlangieri A. Elliott S. Wasiak J. Chao M. Foroudi F. (2022). “Use of magnetic resonance image-guided radiotherapy for breast cancer: A scoping review,” J. Med. Radiat. Sci. 69, 122–133. doi:10.1002/jmrs.545.

Bertelsen A.S. Schytte T. Møller P.K. , et al (2019). “First clinical experiences with a high field 1.5 T MR linac,” Acta. Oncol. 58, 1352–1357. doi:10.1080/0284186x.2019.1627417.

Bertholet J. Knopf A. Eiben B. , et al (2019). “Real-time intrafraction motion monitoring in external beam radiotherapy,” Phys. Med. Biol. 64, 15TR01. doi:10.1088/1361-6560/ab2ba8.

Bohoudi O. Bruynzeel A.M.E. Senan S. , et al (2017). “Fast and robust online adaptive planning in stereotactic MR-guided adaptive radiation therapy (SMART) for pancreatic cancer,” Radiother. Oncol. 125, 439–444. doi:10.1016/j.radonc.2017.07.028.

Brand D.H. Tree A.C. Ostler P. , et al (2019). “Intensity-modulated fractionated radiotherapy versus stereotactic body radiotherapy for prostate cancer (PACE-B): Acute toxicity findings from an international, randomised, open-label, phase 3, non-inferiority trial,” Lancet Oncol. 20, 1531–1543. doi:10.1016/s1470-2045(19)30569-8.

Brock K.K. (2011). “Imaging and image-guided radiation therapy in liver cancer,” Semin. Radiat. Oncol. 21, 247–255. doi:10.1016/j.semradonc.2011.05.001.

Brock K.K. Mutic S. McNutt T.R. Li H. Kessler M.L. (2017). “Use of image registration and fusion algorithms and techniques in radiotherapy: Report of the AAPM Radiation Therapy Committee Task Group No. 132,” Med. Phys. 44, e43–e76. doi:10.1002/mp.12256.

Bronskill M.J. Carson P.L. Einstein S. , et al (1986). Report No. 20—Site Planning for Magnetic Resonance Imaging Systems (American Association of Physicists in Medicine, New York).

Bruynzeel A.M.E. Tetar S.U. Oei S.S. , et al (2019). “A prospective single-arm phase 2 study of stereotactic magnetic resonance guided adaptive radiation therapy for prostate cancer: Early toxicity results,” Int. J. Radiat. Oncol. Biol. Phys. 105, 1086–1094. doi:10.1016/j.ijrobp.2019.08.007.

Byrne H. Le Duc G. Lux F. , et al (2020). “Enhanced MRI-guided radiotherapy with gadolinium-based nanoparticles: Preclinical evaluation with an MRI-linac,” Cancer Nano. 11, 1–14. doi:10.1186/s12645-020-00065-5.

Cai B. Green O.L. Kashani R. , et al (2018). “A practical implementation of physics quality assurance for photon adaptive radiotherapy,” Z. Med. Phys. 28, 211–223. doi:10.1016/j.zemedi.2018.02.002.

Carbucicchio C. Andreini D. Piperno G. , et al (2021). “Stereotactic radioablation for the treatment of ventricular tachycardia: Preliminary data and insights from the STRA-MI-VT phase Ib/II study,” J. Interv. Card. Electrophysiol. 62, 427–439. doi:10.1007/s10840-021-01060-5.

Chen L. Price R.A. Jr. Nguyen T.B. , et al (2004). “Dosimetric evaluation of MRI-based treatment planning for prostate cancer,” Phys. Med. Biol. 49, 5157–5170. doi:10.1088/0031-9155/49/22/010.

Chen X. Ahunbay E. Paulson E.S. Chen G. Li X.A. (2020). “A daily end-to-end quality assurance workflow for MR-guided online adaptive radiation therapy on MR-linac,” J. Appl. Clin. Med. Phys. 21, 205–212. doi:10.1002/acm2.12786.

Chuong M. Clark M. Henke L. , et al (2021). “Patterns of utilization and clinical adoption of 0.35 MR-guided radiation therapy in the United States—Understanding the transition to adaptive, ultra-hypofractionated treatments,” Int. J. Radiat. Oncol. Biol. Phys. 111, e510. doi:10.1016/j.ijrobp.2021.07.1400.

Coles C.E. Griffin C.L. Kirby A.M. , et al (2017). “Partial-breast radiotherapy after breast conservation surgery for patients with early breast cancer (UK IMPORT LOW trial): 5-year results from a multicentre, randomised, controlled, phase 3, non-inferiority trial,” Lancet 390, 1048–1060. doi:10.1016/s0140-6736(17)31145-5.

Constantin D.E. Fahrig R. Keall P.J. (2011). “A study of the effect of in-line and perpendicular magnetic fields on beam characteristics of electron guns in medical linear accelerators,” Med. Phys. 38, 4174–4185. doi:10.1118/1.3600695.

Corradini S. Alongi F. Andratschke N. , et al (2021). “ESTRO-ACROP recommendations on the clinical implementation of hybrid MR-linac systems in radiation oncology,” Radiother. Oncol. 159, 146–154. doi:10.1016/j.radonc.2021.03.025.

Cuccia F. Alongi F. Belka C. , et al (2021a). “Patient positioning and immobilization procedures for hybrid MR-linac systems,” Radiat. Oncol. 16, 183. doi:10.1186/s13014-021-01910-6.

Cuccia F. Rigo M. Gurrera D. , et al (2021b). “Mitigation on bowel loops daily variations by 1.5 T MR-guided daily-adaptive SBRT for abdomino-pelvic lymph-nodal oligometastases,” J. Cancer Res. Clin. Oncol. 147, 3269–3277. doi:10.1007/s00432-021-03739-8.

Cuculich P.S. Schill M.R. Kashani R. , et al (2017). “Noninvasive cardiac radiation for ablation of ventricular tachycardia,” N. Engl. J. Med. 377, 2325–2336. doi:10.1056/NEJMoa1613773.

Cunningham J.M. Barberi E.A. Miller J. Kim J.P. Glide-Hurst C.K. (2019). “Development and evaluation of a novel MR-compatible pelvic end-to-end phantom,” J. Appl. Clin. Med. Phys. 20, 265–275. doi:10.1002/acm2.12455.

Cusumano D. Lenkowicz J. Votta C. , et al (2020). “A deep learning approach to generate synthetic CT in low field MR-guided adaptive radiotherapy for abdominal and pelvic cases,” Radiother. Oncol. 153, 205–212. doi:10.1016/j.radonc.2020.10.018.

de Crevoisier R. Bayar M.A. Pommier P. , et al (2018). “Daily versus weekly prostate cancer image guided radiation therapy: Phase 3 multicenter randomized trial,” Int. J. Radiat. Oncol. Biol. Phys. 102, 1420–1429. doi:10.1016/j.ijrobp.2018.07.2006.

de Leon J. Woods A. Twentyman T. , et al (2021). “Analysis of data to advance personalised therapy with MR-linac (ADAPT-MRL),” Clin. Transl. Radiat. Oncol. 31, 64–70. doi:10.1016/j.ctro.2021.09.004.

de Mol van Otterloo S.R. Christodouleas J.P. Blezer E.L.A , et al (2020). “The MOMENTUM study: An international registry for the evidence-based introduction of MR-guided adaptive therapy,” Front. Oncol. 10, 1328. doi:10.3389/fonc.2020.01328.

de Mol van Otterloo S.R. Christodouleas J.P. Blezer E.L. , et al (2021). “Patterns of care, tolerability, and safety of the first cohort of patients treated on a novel high-field MR-linac within the MOMENTUM study: Initial results from a prospective multi-institutional registry,” Int. J. Radiat. Oncol. Biol. Phys. 111, 867–875. doi:10.1016/j.ijrobp.2021.07.003.

de Pooter J. Billas I. de Prez L. , et al (2021). “Reference dosimetry in MRI-linacs: Evaluation of available protocols and data to establish a code of practice,” Phys. Med. Biol. 66, 05TR02. doi:10.1088/1361-6560/ab9efe.

de Vries J.H.W. Seravalli E. Houweling A.C. , et al (2018). “Characterization of a prototype MR-compatible Delta4 QA system in a 1.5 tesla MR-linac,” Phys. Med. Biol. 63, 02NT02. doi:10.1088/1361-6560/aa9d26.

Dearnaley D. Syndikus I. Mossop H. , et al (2016). “Conventional versus hypofractionated high-dose intensity-modulated radiotherapy for prostate cancer: 5-year outcomes of the randomised, non-inferiority, phase 3 CHHiP trial,” Lancet Oncol. 17, 1047–1060. doi:10.1016/s1470-2045(16)30102-4.

Desai V. Bayouth J. Smilowitz J. Yadav P. (2021). “A clinical validation of the MR-compatible Delta(4) QA system in a 0.35 tesla MR linear accelerator,” J. Appl. Clin. Med. Phys. 22, 82–91. doi:10.1002/acm2.13216.

Ding G.X. Alaei P. Curran B. , et al (2018). “Image guidance doses delivered during radiotherapy: Quantification, management, and reduction: Report of the AAPM Therapy Physics Committee Task Group 180,” Med. Phys. 45, e84–e99. doi:10.1002/mp.12824.

Dunlop A. Mitchell A. Tree A. , et al (2020). “Daily adaptive radiotherapy for patients with prostate cancer using a high field MR-linac: Initial clinical experiences and assessment of delivered doses compared to a C-arm linac,” Clin. Transl. Radiat. Oncol. 23, 35–42. doi:10.1016/j.ctro.2020.04.011.

Eccles C.L. Adair Smith G. Bower L. , et al. (2019). “Magnetic resonance imaging sequence evaluation of an MR Linac system; early clinical experience”, Tech. Innov. Patient Support Radn Oncol. 12, 56–63.

Eijkelenkamp H. Boekhoff M.R. Verweij M.E. , et al (2021). “Planning target volume margin assessment for online adaptive MR-guided dose-escalation in rectal cancer on a 1.5 T MR-linac,” Radiother. Oncol. 162, 150–155. doi:10.1016/j.radonc.2021.07.011.

Elter A. Dorsch S. Mann P. , et al (2019). “End-to-end test of an online adaptive treatment procedure in MR-guided radiotherapy using a phantom with anthropomorphic structures,” Phys. Med. Biol. 64, 225003. doi:10.1088/1361-6560/ab4d8e.

Emami H. Dong M. Nejad-Davarani S.P. Glide-Hurst C.K. (2018). “Generating synthetic CTs from magnetic resonance images using generative adversarial networks,” Med. Phys. 45, 3627–3636. doi:10.1002/mp.13047.

Fallone B.G. Murray B. Rathee S. , et al (2009). “First MR images obtained during megavoltage photon irradiation from a prototype integrated linac-MR system,” Med. Phys. 36, 2084–2088. doi:10.1118/1.3125662.

Ferris W.S. Kissick M.W. Bayouth J.E. Culberson W.S. Smilowitz J.B. (2020). “Evaluation of radixact motion synchrony for 3D respiratory motion: Modeling accuracy and dosimetric fidelity,” J. Appl. Clin. Med. Phys. 21, 96–106. doi:10.1002/acm2.12978.

Finazzi T. van Sörnsen de Koste J.R. Palacios M.A. , et al (2020). “Delivery of magnetic resonance-guided single-fraction stereotactic lung radiotherapy,” Phys. Imaging Radiat. Oncol. 14, 17–23. doi:10.1016/j.phro.2020.05.002.

Fischer-Valuck B.W. Henke L. Green O. , et al (2017). “Two-and-a-half-year clinical experience with the world’s first magnetic resonance image guided radiation therapy system,” Adv. Radiat. Oncol. 2, 485–493. doi:10.1016/j.adro.2017.05.006.

Fraass B. Doppke K. Hunt M. , et al (1998). “American Association of Physicists in Medicine Radiation Therapy Committee Task Group 53: Quality assurance for clinical radiotherapy treatment planning,” Med. Phys. 25, 1773–1829. doi:10.1118/1.598373.

Fu Y. Mazur T.R. Wu X. , et al (2018). “A novel MRI segmentation method using CNN-based correction network for MRI-guided adaptive radiotherapy,” Med. Phys. 45, 5129–5137. doi:10.1002/mp.13221.

Gach H.M. Green O.L. Mackey S.L. , et al (2022). “Implementation of magnetic resonance safety program for radiation oncology,” Pract. Radiat. Oncol. 12, e49–e55. doi:10.1016/j.prro.2021.08.008.

Gao Y. Yoon S. Savjani R. , et al (2021). “Comparison and evaluation of distortion correction techniques on an MR-guided radiotherapy system,” Med. Phys. 48, 691–702. doi:10.1002/mp.14634.

Gao Y. Zhou Z. Han F. , et al (2018). “Accelerated 3D bSSFP imaging for treatment planning on an MRI-guided radiotherapy system,” Med. Phys. 45, 2595–2602. doi:10.1002/mp.12924.

Garcia Schüler H.I. Pavic M. Mayinger M. , et al (2021). “Operating procedures, risk management and challenges during implementation of adaptive and non-adaptive MR-guided radiotherapy: 1-year single-center experience,” Radiat. Oncol. 16, 217. doi:10.1186/s13014-021-01945-9.

Gassenmaier S. Küstner T. Nickel D. , et al (2021). “Deep learning applications in magnetic resonance imaging: Has the future become present?” Diagnostics 11, 2181. doi:10.3390/diagnostics11122181.

Glide-Hurst C.K. Lee P. Yock A.D. , et al (2021a). “Adaptive radiation therapy (ART) strategies and technical considerations: A state of the ART review from NRG Oncology,” Int. J. Radiat. Oncol. Biol. Phys. 109, 1054–1075. doi:10.1016/j.ijrobp.2020.10.021.

Glide-Hurst C.K. Paulson E.S. McGee K. , et al (2021b). “Task Group 284 Report: Magnetic resonance imaging simulation in radiotherapy: Considerations for clinical implementation, optimization, and quality assurance,” Med. Phys. 48, e636–e670. doi:10.1002/mp.14695.

Godoy Scripes P. Subashi E. Burleson S. , et al (2020). “Impact of varying air cavity on planning dosimetry for rectum patients treated on a 1.5 T hybrid MR-linac system,” J. Appl. Clin. Med. Phys. 21, 144–152. doi:10.1002/acm2.12903.

Gomez D.R. Blumenschein G.R. Jr. Lee J.J. , et al (2016). “Local consolidative therapy versus maintenance therapy or observation for patients with oligometastatic non-small-cell lung cancer without progression after first-line systemic therapy: A multicentre, randomised, controlled, phase 2 study,” Lancet Oncol. 17, 1672–1682. doi:10.1016/s1470-2045(16)30532-0.

Green O.L. Henke L.E. Hugo G.D. (2019). “Practical clinical workflows for online and offline adaptive radiation therapy,” Semin. Radiat. Oncol. 29, 219–227. doi:10.1016/j.semradonc.2019.02.004.

Guckenberger M. Richter A. Boda-Heggemann J. Lohr F. (2012). “Motion compensation in radiotherapy,” Crit. Rev. Biomed. Eng. 40, 187–197. doi:10.1615/critrevbiomedeng.v40.i3.30.

Güngör G. Serbez İ. Temur B. , et al (2021). “Time analysis of online adaptive magnetic resonance-guided radiation therapy workflow according to anatomical sites,” Pract. Radiat. Oncol. 11, e11–e21. doi:10.1016/j.prro.2020.07.003.

Gupta A. Dunlop A. Mitchell A. , et al (2022). “Online adaptive radiotherapy for head and neck cancers on the MR linear Accelerator: Introducing a novel modified Adapt-to-Shape approach,” Clin. Transl. Radiat. Oncol. 32, 48–51. doi:10.1016/j.ctro.2021.11.001.

Hackett S.L. van Asselen B. Wolthaus J.W. , et al (2016). “Consequences of air around an ionization chamber: Are existing solid phantoms suitable for reference dosimetry on an MR-linac?” Med. Phys. 43, 3961. doi:10.1118/1.4952727.

Hackett S.L. van Asselen B. Wolthaus J.W.H. , et al (2018). “Spiraling contaminant electrons increase doses to surfaces outside the photon beam of an MRI-linac with a perpendicular magnetic field,” Phys. Med. Biol. 63, 095001. doi:10.1088/1361-6560/aaba8f.

Hales R.B. Rodgers J. Whiteside L. , et al (2020). “Therapeutic radiographers at the helm: Moving towards radiographer-led MR-guided radiotherapy,” J. Med. Imaging. Radiat. Sci. 51, 364–372. doi:10.1016/j.jmir.2020.05.001.

Hall W.A. Kishan A.U. Hall E. , et al (2022). “Adaptive magnetic resonance image guided radiotherapy for intact prostate cancer: How to optimally test an emerging technology,” Front. Oncol. 12, 962897. doi:10.3389/fonc.2022.962897.

Hara W. Soltys S.G. Gibbs I.C. (2007). “CyberKnife robotic radiosurgery system for tumor treatment,” Expert Rev. Anticancer Ther. 7, 1507–1515. doi:10.1586/14737140.7.11.1507.

Hehakaya C. Van der Voort van Zyp J. Lagendijk J.J. , et al (2020). “Problems and promises of introducing the magnetic resonance imaging linear accelerator into routine care: The case of prostate cancer,” Front. Oncol. 10, 1741. doi:10.3389/fonc.2020.01741.

Henke L. Kashani R. Robinson C. , et al (2018). “Phase I trial of stereotactic MR-guided online adaptive radiation therapy (SMART) for the treatment of oligometastatic or unresectable primary malignancies of the abdomen,” Radiother. Oncol. 126, 519–526. doi:10.1016/j.radonc.2017.11.032.

Heukelom J. Fuller C.D. (2019). “Head and neck cancer Adaptive Radiation Therapy (ART): Conceptual considerations for the informed clinician,” Semin. Radiat. Oncol. 29, 258–273. doi:10.1016/j.semradonc.2019.02.008.

Hewson E. Nguyen D.T. Booth J.T. Hugo G. Keall P.J. (2020). “Adaptive radiation therapy,” in Modern Technology of Radiation Oncology, van Dyk J ., Ed., Vol. 4. 259–299. (Medical Physics Publishing, Madison, WI).

Hickey B.E. Lehman M. Francis D.P. See A.M. (2016). “Partial breast irradiation for early breast cancer,” Cochrane Database Syst. Rev. 7, Cd007077. doi:10.1002/14651858.CD007077.pub3.

Hiraoka M. Matsuo Y. Sawada A. , et al (2012). “Realization of dynamic tumor tracking irradiation with real-time monitoring in lung tumor patients using a gimbaled X-ray head radiation therapy equipment,” Int. J. Radiat. Oncol. Biol. Phys. 84, S560–S561. doi:10.1016/j.ijrobp.2012.07.1493.

Hissoiny S. Raaijmakers A.J. Ozell B. Després P. Raaymakers B.W. (2011). “Fast dose calculation in magnetic fields with GPUMCD,” Phys. Med. Biol. 56, 5119–5129. doi:10.1088/0031-9155/56/16/003.

Hoffmans D. Niebuhr N. Bohoudi O. Pfaffenberger A. Palacios M. (2020). “An end-to-end test for MR-guided online adaptive radiotherapy,” Phys. Med. Biol. 65, 125012. doi:10.1088/1361-6560/ab8955.

Houweling A.C. de Vries J.H. Wolthaus J. , et al (2016). “Performance of a cylindrical diode array for use in a 1.5 T MR-linac,” Phys. Med. Biol. 61, N80–N89. doi:10.1088/0031-9155/61/3/n80.

Huq M.S. Fraass B.A. Dunscombe P.B. , et al (2016). “The report of Task Group 100 of the AAPM: Application of risk analysis methods to radiation therapy quality management,” Med. Phys. 43, 4209–4262. doi:10.1118/1.4947547.

IAEA (2001). Absorbed Dose Determination in External Beam Radiotherapy (International Atomic Energy Agency, Vienna, Austria).

Iakovenko V. Keller B. Sahgal A. Sarfehnia A. (2020). “Experimental measurement of ionization chamber angular response and associated magnetic field correction factors in MR-linac,” Med. Phys. 47, 1940–1948. doi:10.1002/mp.14025.

International Commission on Radiation Units and Measurements (ICRU) (2010). “Prescribing, recording, and reporting photon-beam intensity-modulated radiation therapy (IMRT): Report 83,” J. ICRU 10, 1–92. doi:10.1093/jicru/ndq002.

Intven M.P.W. de Mol van Otterloo S.R. Mook S. , et al (2021). “Online adaptive MR-guided radiotherapy for rectal cancer; Feasibility of the workflow on a 1.5T MR-linac: Clinical implementation and initial experience,” Radiother. Oncol. 154, 172–178. doi:10.1016/j.radonc.2020.09.024.

Jackson S. Glitzner M. Tijssen R.H.N. Raaymakers B.W. (2019). “MRI B (0) homogeneity and geometric distortion with continuous linac gantry rotation on an Elekta Unity MR-linac,” Phys. Med. Biol. 64, 12NT01. doi:10.1088/1361-6560/ab231a.

Jaffray D.A. (2012). “Image-guided radiotherapy: From current concept to future perspectives,” Nat. Rev. Clin. Oncol. 9, 688–699. doi:10.1038/nrclinonc.2012.194.

Jaffray D.A. Lindsay P.E. Brock K.K. Deasy J.O. Tomé W.A. (2010). “Accurate accumulation of dose for improved understanding of radiation effects in normal tissue,” Int. J. Radiat. Oncol. Biol. Phys. 76, S135–S139. doi:10.1016/j.ijrobp.2009.06.093.

Jia X. Gu X. Graves Y.J. Folkerts M. Jiang S.B. (2011). “GPU-based fast Monte Carlo simulation for radiotherapy dose calculation,” Phys. Med. Biol. 56, 7017–7031. doi:10.1088/0031-9155/56/22/002.

Kanal E. Barkovich A.J. Bell C. , et al (2013). “ACR guidance document on MR safe practices: 2013,” J. Magn. Reson. Imaging 37, 501–530.

Keall P.J. Barton M. Crozier S. (2014). “The Australian magnetic resonance imaging-linac program,” Semin. Radiat. Oncol. 24, 203–206. doi:10.1016/j.semradonc.2014.02.015.

Keall P.J. Brighi C. Glide-Hurst C. , et al (2022). “Integrated MRI-guided radiotherapy—Opportunities and challenges,” Nat. Rev. Clin. Oncol. 19, 458–470. doi:10.1038/s41571-022-00631-3.

Keall P.J. Mageras G.S. Balter J.M. , et al (2006). “The management of respiratory motion in radiation oncology report of AAPM Task Group 76,” Med. Phys. 33, 3874–3900. doi:10.1118/1.2349696.

Keall P.J. Nguyen D.T. O’Brien R. , et al (2018a). “The first clinical implementation of real-time image-guided adaptive radiotherapy using a standard linear accelerator,” Radiother. Oncol. 127, 6–11. doi:10.1016/j.radonc.2018.01.001.

Keall P.J. Nguyen D.T. O’Brien R. , et al (2018b). “Review of real-time 3-dimensional image guided radiation therapy on standard-equipped cancer radiation therapy systems: Are we at the tipping point for the era of real-time radiation therapy?” Int. J. Radiat. Oncol. Biol. Phys. 102, 922–931. doi:10.1016/j.ijrobp.2018.04.016.

Keall P.J. Sawant A. Berbeco R.I. , et al (2021). “AAPM Task Group 264: The safe clinical implementation of MLC tracking in radiotherapy,” Med. Phys. 48, e44–e64. doi:10.1002/mp.14625.

Keesman R. van der Bijl E. Janssen T.M. , et al (2020). “Clinical workflow for treating patients with a metallic hip prosthesis using magnetic resonance imaging-guided radiotherapy,” Phys. Imaging Radiat. Oncol. 15, 85–90. doi:10.1016/j.phro.2020.07.010.

Kennedy W.R. Thomas M.A. Stanley J.A. , et al (2020). “Single-institution phase 1/2 prospective clinical trial of single-fraction, high-gradient adjuvant partial-breast irradiation for hormone sensitive stage 0-I breast cancer,” Int. J. Radiat. Oncol. Biol. Phys. 107, 344–352. doi:10.1016/j.ijrobp.2020.02.021.

Kerkmeijer L.G.W. Groen V.H. Pos F.J. , et al (2021). “Focal boost to the intraprostatic tumor in external beam radiotherapy for patients with localized prostate cancer: Results from the FLAME randomized phase III trial,” J. Clin. Oncol. 39, 787–796. doi:10.1200/jco.20.02873.

Kim A. Lim-Reinders S. Ahmad S.B. Sahgal A. Keller B.M. (2020a). “Surface and near-surface dose measurements at beam entry and exit in a 1.5 T MR-linac using optically stimulated luminescence dosimeters,” Phys. Med. Biol. 65, 045012. doi:10.1088/1361-6560/ab64b6.

Kim J. Garbarino K. Schultz L. , et al (2015). “Dosimetric evaluation of synthetic CT relative to bulk density assignment-based magnetic resonance-only approaches for prostate radiotherapy,” Radiat. Oncol. 10, 239–239. doi:10.1186/s13014-015-0549-7.

Kim T. Lewis B.C. Price A. , et al (2020b). “Direct tumor visual feedback during free breathing in 0.35T MRgRT,” J. Appl. Clin. Med. Phys. 21, 241–247. doi:10.1002/acm2.13016.

Kirby M.C. Ryde S. Hall C. (2006). Acceptance Testing and Commissioning of Linear Accelerators (IPEM, York, England).

Kirkby C. Stanescu T. Rathee S. , et al (2008). “Patient dosimetry for hybrid MRI-radiotherapy systems,” Med. Phys. 35, 1019–1027. doi:10.1118/1.2839104.

Kishan A.U. Lamb J. Casado M. , et al (2022a). “Magnetic resonance imaging-guided versus computed tomography-guided stereotactic body radiotherapy for prostate cancer (MIRAGE): Interim analysis of a phase III randomized trial,” J. Clin. Oncol. 40, 255–255. doi:10.1200/JCO.2022.40.6_suppl.255.

Kishan A.U. Ma T. Lamb J. , et al (2022b). “Magnetic resonance imaging-guided vs. computed tomography-guided stereotactic body radiotherapy for prostate cancer (MIRAGE): Primary endpoint analysis of a phase III randomized trial,” Int. J. Radiat. Oncol. Biol. Phys. 114, S92–S93. doi:10.1016/j.ijrobp.2022.07.507.

Klawikowski S. Tai A. Ates O. Ahunbay E. Li X.A. (2018). “A fast 4D IMRT/VMAT planning method based on segment aperture morphing,” Med. Phys. 45, 1594–1602. doi:10.1002/mp.12778.

Klein E.E. Hanley J. Bayouth J. , et al (2009). “Task group 142 report: Quality assurance of medical accelerators,” Med. Phys. 36, 4197–4212. doi:10.1118/1.3190392.

Klüter S. (2019). “Technical design and concept of a 0.35 T MR-linac,” Clin. Transl. Radiat. Oncol. 18, 98–101. doi:10.1016/j.ctro.2019.04.007.

Klüter S. Schrenk O. Renkamp C.K. , et al (2021). “A practical implementation of risk management for the clinical introduction of online adaptive magnetic resonance-guided radiotherapy,” Phys. Imaging Radiat. Oncol. 17, 53–57. doi:10.1016/j.phro.2020.12.005.

Köhler M. Vaara T. Van Grootel M. , et al (2015). “MR-only simulation for radiotherapy planning,” White paper: Phillips MRCAT for prostate dose calculations using only MRI data. https://www.documents.philips.com/doclib/enc/fetch/2000/4504/577242/577251/587787/White_Paper_MR-only_sim_LR.pdf.

Kontaxis C. Bol G.H. Stemkens B. , et al (2017). “Towards fast online intrafraction replanning for free-breathing stereotactic body radiation therapy with the MR-linac,” Phys. Med. Biol. 62, 7233–7248. doi:10.1088/1361-6560/aa82ae.

Kontaxis C. de Muinck Keizer D.M. Kerkmeijer L.G.W. , et al (2020). “Delivered dose quantification in prostate radiotherapy using online 3D cine imaging and treatment log files on a combined 1.5T magnetic resonance imaging and linear accelerator system,” Phys. Imaging Radiat. Oncol. 15, 23–29. doi:10.1016/j.phro.2020.06.005.

Kontaxis C. Woodhead P.L. Bol G.H. Lagendijk J.J.W. Raaymakers B.W. (2021). “Proof-of-concept delivery of intensity modulated arc therapy on the Elekta Unity 1.5 T MR-linac,” Phys. Med. Biol. 66, 04LT01. doi:10.1088/1361-6560/abd66d.

Kooreman E.S. van Houdt P.J. Keesman R. , et al (2020). “ADC measurements on the Unity MR-linac: A recommendation on behalf of the Elekta Unity MR-linac consortium,” Radiother. Oncol. 153, 106–113. doi:10.1016/j.radonc.2020.09.046.

Kooreman E.S. van Houdt P.J. Nowee M.E. , et al (2019). “Feasibility and accuracy of quantitative imaging on a 1.5 T MR-linear accelerator,” Radiother. Oncol. 133, 156–162. doi:10.1016/j.radonc.2019.01.011.

Kupelian P.A. Lee C. Langen K.M. , et al (2008). “Evaluation of image-guidance strategies in the treatment of localized prostate cancer,” Int. J. Radiat. Oncol. Biol. Phys. 70, 1151–1157. doi:10.1016/j.ijrobp.2007.07.2371.

Lamb J. Cao M. Kishan A. , et al (2017). “Online adaptive radiation therapy: Implementation of a new process of care,” Cureus 9, e1618. doi:10.7759/cureus.1618.

Latifi K. Moros E.G. Zhang G. Harrison L. Feygelman V. (2019). “A method to determine the coincidence of MRI-guided linac radiation and magnetic isocenters,” Technol. Cancer Res. Treat. 18, 1533033819877986. doi:10.1177/1533033819877986.

Lee J. Bates M. Shepherd E. , et al (2021). “Cardiac stereotactic ablative radiotherapy for control of refractory ventricular tachycardia: Initial UK multicentre experience,” Open Heart 8, e001770. doi:10.1136/openhrt-2021-001770.

Lenkowicz J. Votta C. Nardini M. , et al (2022). “A deep learning approach to generate synthetic CT in low field MR-guided radiotherapy for lung cases,” Radiother. Oncol. 176, 31–38. doi:10.1016/j.radonc.2022.08.028.

Lewis B.C. Guta A. Mackey S. , et al (2021a). “Evaluation of diffusion-weighted MRI and geometric distortion on a 0.35T MR-LINAC at multiple gantry angles,” J. Appl. Clin. Med. Phys. 22, 118–125. doi:10.1002/acm2.13135.

Lewis B.C. Shin J. Quinn B. , et al (2021b). “First clinical experience of correcting phantom-based image distortion related to gantry position on a 0.35T MR-linac,” J. Appl. Clin. Med. Phys. 22, 21–28. doi:10.1002/acm2.13404.

Lim K. Stewart J. Kelly V. , et al (2014). “Dosimetrically triggered adaptive intensity modulated radiation therapy for cervical cancer,” Int. J. Radiat. Oncol. Biol. Phys. 90, 147–154. doi:10.1016/j.ijrobp.2014.05.039.

Lim S.B. Godoy Scripes P. Napolitano M. , et al (2021). “An investigation of using log-file analysis for automated patient-specific quality assurance in MRgRT,” J. Appl. Clin. Med. Phys. 22, 183–188. doi:10.1002/acm2.13361.

Lim S.N. Ahunbay E.E. Nasief H. , et al (2020). “Indications of online adaptive replanning based on organ deformation,” Pract. Radiat. Oncol. 10, e95–e102. doi:10.1016/j.prro.2019.08.007.

Ling C.C. Humm J. Larson S. , et al (2000). “Towards multidimensional radiotherapy (MD-CRT): Biological imaging and biological conformality,” Int. J. Radiat. Oncol. Biol. Phys. 47, 551–560. doi:10.1016/s0360-3016(00)00467-3.

Liu P.Z.Y. Dong B. Nguyen D.T. , et al (2020). “First experimental investigation of simultaneously tracking two independently moving targets on an MRI-linac using real-time MRI and MLC tracking,” Med. Phys. 47, 6440–6449. doi:10.1002/mp.14536.

Lustig M. Donoho D. Pauly J.M. (2007). “Sparse MRI: The application of compressed sensing for rapid MR imaging,” Magn. Reson. Med. 58, 1182–1195. doi:10.1002/mrm.21391.

Luterstein E. Cao M. Lamb J.M. , et al (2020). “Clinical outcomes using magnetic resonance-guided stereotactic body radiation therapy in patients with locally advanced cholangiocarcinoma,” Adv. Radiat. Oncol. 5, 189–195. doi:10.1016/j.adro.2019.09.008.

Ma T.M. Ballas L.K. Wilhalme H. , et al (2022). “Quality-of-life outcomes and toxicity profile among patients with localized prostate cancer after radical prostatectomy treated with stereotactic body radiation: The SCIMITAR multi-center phase 2 trial,” Int. J. Radiat. Oncol. Biol. Phys. in press (11pp). doi:10.1016/j.ijrobp.2022.08.041.

Ma T.M. Lamb J.M. Casado M. , et al (2021a). “Magnetic resonance imaging-guided stereotactic body radiotherapy for prostate cancer (mirage): A phase III randomized trial,” BMC Cancer 21, 538. doi:10.1186/s12885-021-08281-x.

Ma T.M. Neylon J. Casado M. , et al (2021b). “Dosimetric impact of interfraction prostate and seminal vesicle volume changes and rotation: A post-hoc analysis of a phase III randomized trial of MRI-guided versus CT-guided stereotactic body radiotherapy,” Radiother. Oncol. 167, 203–210. doi:10.1016/j.radonc.2021.12.037.

Malkov V.N. Rogers D.W.O. (2018). “Monte Carlo study of ionization chamber magnetic field correction factors as a function of angle and beam quality,” Med. Phys. 45, 908–925. doi:10.1002/mp.12716.

Malkov V.N. Rogers D.W.O. (2019). “Erratum: Monte Carlo study of ionization chamber magnetic field correction factors as a function of angle and beam quality [Med. Phys. 45(2), 908–925 (2018)],” Med. Phys. 46, 5367–5370. doi:10.1002/mp.13782.

Malkov V.N. Hackett S.L. Wolthaus J.W.H. Raaymakers B.W. van Asselen B. (2019). “Monte Carlo simulations of out-of-field surface doses due to the electron streaming effect in orthogonal magnetic fields,” Phys. Med. Biol. 64, 115029. doi:10.1088/1361-6560/ab0aa0.

Mayinger M. Kovacs B. Tanadini-Lang S. , et al (2020). “First magnetic resonance imaging-guided cardiac radioablation of sustained ventricular tachycardia,” Radiother. Oncol. 152, 203–207. doi:10.1016/j.radonc.2020.01.008.

Mazzola R. Figlia V. Rigo M. , et al (2020). “Feasibility and safety of 1.5 T MR-guided and daily adapted abdominal-pelvic SBRT for elderly cancer patients: Geriatric assessment tools and preliminary patient-reported outcomes,” J. Cancer Res. Clin. Oncol. 146, 2379–2397. doi:10.1007/s00432-020-03230-w.

McGee K.P. Hwang K.P. Sullivan D.C. , et al (2021). “Magnetic resonance biomarkers in radiation oncology: The report of AAPM Task Group 294,” Med. Phys. 48, e697–e732. doi:10.1002/mp.14884.

McNair H.A. Joyce E. O’Gara G. , et al (2021). “Radiographer-led online image guided adaptive radiotherapy: A qualitative investigation of the therapeutic radiographer role,” Radiography 27, 1085–1093. doi:10.1016/j.radi.2021.04.012.

Meattini I. Marrazzo L. Saieva C. , et al (2020). “Accelerated partial-breast irradiation compared with whole-breast irradiation for early breast cancer: Long-term results of the randomized phase III APBI-IMRT-Florence trial,” J. Clin. Oncol. 38, 4175–4183. doi:10.1200/jco.20.00650.

Medicines and Healthcare Products Regulatory Agency (2015). “Safety Guidelines for Magnetic Resonance Imaging Equipment in Clinical Use.” Canary Wharf, London, UK.

Meijsing I. Raaymakers B.W. Raaijmakers A.J. , et al (2009). “Dosimetry for the MRI accelerator: The impact of a magnetic field on the response of a Farmer NE2571 ionization chamber,” Phys. Med. Biol. 54, 2993–3002. doi:10.1088/0031-9155/54/10/002.

Menten M.J. Mohajer J.K. Nilawar R. , et al (2020). “Automatic reconstruction of the delivered dose of the day using MR-linac treatment log files and online MR imaging,” Radiother. Oncol. 145, 88–94. doi:10.1016/j.radonc.2019.12.010.

Mickevicius N.J. Kim J.P. Zhao J. , et al (2021). “Toward magnetic resonance fingerprinting for low-field MR-guided radiation therapy,” Med. Phys. 48, 6930–6940. doi:10.1002/mp.15202.

Mittauer K.E. Hill P.M. Bassetti M.F. Bayouth J.E. (2020). “Validation of an MR-guided online adaptive radiotherapy (MRgoART) program: Deformation accuracy in a heterogeneous, deformable, anthropomorphic phantom,” Radiother. Oncol. 146, 97–109. doi:10.1016/j.radonc.2020.02.012.

Mönnich D. Winter J. Nachbar M. , et al (2020). “Quality assurance of IMRT treatment plans for a 1.5 T MR-linac using a 2D ionization chamber array and a static solid phantom,” Phys. Med. Biol. 65, 16NT01. doi:10.1088/1361-6560/aba5ec.

Murray Brunt A. Haviland J.S. Wheatley D.A. , et al (2020). “Hypofractionated breast radiotherapy for 1 week versus 3 weeks (FAST-Forward): 5-year efficacy and late normal tissue effects results from a multicentre, non-inferiority, randomised, phase 3 trial,” Lancet 395, 1613–1626. doi:10.1016/s0140-6736(20)30932-6.

Mutic S. Dempsey J.F. (2014). “The ViewRay system: Magnetic resonance-guided and controlled radiotherapy,” Semin. Radiat. Oncol. 24, 196–199. doi:10.1016/j.semradonc.2014.02.008.

Mutic S. Palta J.R. Butker E.K. , et al (2003). “Quality assurance for computed-tomography simulators and the computed-tomography-simulation process: Report of the AAPM Radiation Therapy Committee Task Group No. 66,” Med. Phys. 30, 2762–2792. doi:10.1118/1.1609271.

Nejad-Davarani S.P. Zakariaei N. Chen Y. , et al (2020). “Rapid multicontrast brain imaging on a 0.35T MR-linac,” Med. Phys. 47, 4064–4076. doi:10.1002/mp.14251.

Neph R. Lyu Q. Huang Y. Yang Y.M. Sheng K. (2021). “DeepMC: A deep learning method for efficient Monte Carlo beamlet dose calculation by predictive denoising in magnetic resonance-guided radiotherapy,” Phys. Med. Biol. 66, 035022. doi:10.1088/1361-6560/abca01.

Noel C.E. Parikh P.J. Spencer C.R. , et al (2015). “Comparison of onboard low-field magnetic resonance imaging versus onboard computed tomography for anatomy visualization in radiotherapy,” Acta. Oncol. 54, 1474–1482. doi:10.3109/0284186x.2015.1062541.

Noel C.E. Santanam L. Parikh P.J. Mutic S. (2014). “Process-based quality management for clinical implementation of adaptive radiotherapy,” Med. Phys. 41, 081717. doi:10.1118/1.4890589.

Nowee M.E. van Pelt V.W.J. Walraven I. , et al (2021). “The impact of image acquisition time on registration, delineation and image quality for magnetic resonance guided radiotherapy of prostate cancer patients,” Phys. Imaging Radiat. Oncol. 19, 85–89. doi:10.1016/j.phro.2021.07.002.

Oborn B.M. Burigo L.N. (2021). “Monte Carlo modelling in magnetic fields,” pp. 193–208 in Monte Carlo Techniques in Radiation Therapy, Seco J. Verhaegen F ., Eds. (CRC Press, Boca Raton, FL).

Oborn B.M. Dowdell S. Metcalfe P.E. , et al (2017). “Future of medical physics: Real-time MRI-guided proton therapy,” Med. Phys. 44, e77–e90. doi:10.1002/mp.12371.

Oborn B.M. Ge Y. Hardcastle N. Metcalfe P.E. Keall P.J. (2016). “Dose enhancement in radiotherapy of small lung tumors using inline magnetic fields: A Monte Carlo based planning study,” Med. Phys. 43, 368. doi:10.1118/1.4938580.

Oborn B.M. Metcalfe P.E. Butson M.J. Rosenfeld A.B. (2009). “High resolution entry and exit Monte Carlo dose calculations from a linear accelerator 6 MV beam under the influence of transverse magnetic fields,” Med. Phys. 36, 3549–3559. doi:10.1118/1.3157203.

Oborn B.M. Metcalfe P.E. Butson M.J. Rosenfeld A.B. (2010). “Monte Carlo characterization of skin doses in 6 MV transverse field MRI-linac systems: Effect of field size, surface orientation, magnetic field strength, and exit bolus,” Med. Phys. 37, 5208–5217. doi:10.1118/1.3488980.

Oborn B.M. Metcalfe P.E. Butson M.J. Rosenfeld A.B. Keall P.J. (2012). “Electron contamination modeling and skin dose in 6 MV longitudinal field MRIgRT: Impact of the MRI and MRI fringe field,” Med. Phys. 39, 874–890. doi:10.1118/1.3676181.

O’Brien D.J. Sawakuchi G.O. (2017). “Monte Carlo study of the chamber-phantom air gap effect in a magnetic field,” Med. Phys. 44, 3830–3838. doi:10.1002/mp.12290.

O’Brien D.J. Dolan J. Pencea S. Schupp N. Sawakuchi G.O. (2018). “Relative dosimetry with an MR-linac: Response of ion chambers, diamond, and diode detectors for off-axis, depth dose, and output factor measurements,” Med. Phys. 45, 884–897. doi:10.1002/mp.12699.

O’Brien D.J. Roberts D.A. Ibbott G.S. Sawakuchi G.O. (2016). “Reference dosimetry in magnetic fields: Formalism and ionization chamber correction factors,” Med. Phys. 43, 4915. doi:10.1118/1.4959785.

O’Connor J.P. Aboagye E.O. Adams J.E. , et al (2017). “Imaging biomarker roadmap for cancer studies,” Nat. Rev. Clin. Oncol. 14, 169–186. doi:10.1038/nrclinonc.2016.162.

Olaciregui-Ruiz I. Vivas-Maiques B. van der Velden S. , et al (2021). “Automatic dosimetric verification of online adapted plans on the Unity MR-Linac using 3D EPID dosimetry,” Radiother. Oncol. 157, 241–246. doi:10.1016/j.radonc.2021.01.037.

Olberg S. Green O. Cai B. , et al (2018). “Optimization of treatment planning workflow and tumor coverage during daily adaptive magnetic resonance image guided radiation therapy (MR-IGRT) of pancreatic cancer,” Radiat. Oncol. 13, 51. doi:10.1186/s13014-018-1000-7.

Olch A.J. Gerig L. Li H. Mihaylov I. Morgan A. (2014). “Dosimetric effects caused by couch tops and immobilization devices: Report of AAPM Task Group 176,” Med. Phys. 41, 061501. doi:10.1118/1.4876299.

Oleĭnik I. Klepper L. (1973). “Determination of the optimal dynamic conditions for irradiating malignant neoplasms and adaptive radiation treatment,” Med. Radiol. 18, 49–54.

Overweg J. Raaymakers B.W. Lagendijk J.J. Brown K.J. (April, 2009). “System for MRI guided radiotherapy,” International Society for Magnetic Resonance in Medicine 17th Annual Meeting, Honolulu, HI.

Palma D.A. Olson R. Harrow S. , et al (2019). “Stereotactic ablative radiotherapy versus standard of care palliative treatment in patients with oligometastatic cancers (SABR-COMET): A randomised, phase 2, open-label trial,” Lancet 393, 2051–2058. doi:10.1016/s0140-6736(18)32487-5.

Parikh N.R. Lee P.P. Raman S.S. , et al (2020). “Time-driven activity-based costing comparison of CT-guided versus MR-guided SBRT,” JCO Oncol. Pract. 16, e1378–e1385. doi:10.1200/jop.19.00605.

Park J.M. Park S.Y. Kim H.J. , et al (2016). “A comparative planning study for lung SABR between tri-Co-60 magnetic resonance image guided radiation therapy system and volumetric modulated arc therapy,” Radiother. Oncol. 120, 279–285. doi:10.1016/j.radonc.2016.06.013.

Pathmanathan A.U. McNair H.A. Schmidt M.A. , et al (2019). “Comparison of prostate delineation on multimodality imaging for MR-guided radiotherapy,” Br. J. Radiol. 92, 20180948.

Pathmanathan A.U. van As N.J. Kerkmeijer L.G.W. , et al (2018). ‘Magnetic resonance imaging-guided adaptive radiation therapy: A “Game Changer’ for prostate treatment?” Int. J. Radiat. Oncol. Biol. Phys. 100, 361–373. doi:10.1016/j.ijrobp.2017.10.020.

Paudel M.R. Kim A. Sarfehnia A. , et al (2016). “Experimental evaluation of a GPU-based Monte Carlo dose calculation algorithm in the Monaco treatment planning system,” J. Appl. Clin. Med. Phys. 17, 230–241. doi:10.1120/jacmp.v17i6.6455.

Paulson E.S. Erickson B. Schultz C. Allen Li X . (2015). “Comprehensive MRI simulation methodology using a dedicated MRI scanner in radiation oncology for external beam radiation treatment planning,” Med. Phys. 42, 28–39. doi:10.1118/1.4896096.

Pham J. Cao M. Yoon S.M. , et al (2022). “Dosimetric effects of air cavities for MRI-guided online adaptive radiation therapy (MRgART) of prostate bed after radical prostatectomy,” J. Clin. Med. 11, 364. doi:10.3390/jcm11020364.

Prior P. Chen X. Botros M. , et al (2016). “MRI-based IMRT planning for MR-linac: Comparison between CT- and MRI-based plans for pancreatic and prostate cancers,” Phys. Med. Biol. 61, 3819–3842. doi:10.1088/0031-9155/61/10/3819.

Raaijmakers A.J. Raaymakers B.W. Lagendijk J.J. (2008). “Magnetic-field-induced dose effects in MR-guided radiotherapy systems: Dependence on the magnetic field strength,” Phys. Med. Biol. 53, 909–923. doi:10.1088/0031-9155/53/4/006.

Raaymakers B.W. Jürgenliemk-Schulz I. Bol G. , et al (2017). “First patients treated with a 1.5 T MRI-Linac: Clinical proof of concept of a high-precision, high-field MRI guided radiotherapy treatment,” Phys. Med. Biol. 62, L41–L50. doi:10.1088/1361-6560/aa9517.

Raaymakers B.W. Lagendijk J.J. Overweg J. , et al (2009). “Integrating a 1.5 T MRI scanner with a 6 MV accelerator: Proof of concept,” Phys. Med. Biol. 54, N229–N237. doi:10.1088/0031-9155/54/12/n01.

Raaymakers B.W. Raaijmakers A.J. Lagendijk J.J. (2008). “Feasibility of MRI guided proton therapy: Magnetic field dose effects,” Phys. Med. Biol. 53, 5615–5622. doi:10.1088/0031-9155/53/20/003.

RCR (2021). Postoperative Radiotherapy for Breast Cancer: Hypofractionation RCR Consensus Statements (The Royal College of Radiologists, London, UK).

Regnery S. Buchele C. Piskorski L. , et al (2022). “SMART ablation of lymphatic oligometastases in the pelvis and abdomen: Clinical and dosimetry outcomes,” Radiother. Oncol. 168, 106–112. doi:10.1016/j.radonc.2022.01.038.

Reynolds M. Rathee S. Fallone B.G. (2017). “Technical Note: Ion chamber angular dependence in a magnetic field,” Med. Phys. 44, 4322–4328. doi:10.1002/mp.12405.

Reynoso F.J. Curcuru A. Green O. , et al (2016). “Technical note: Magnetic field effects on Gafchromic-film response in MR-IGRT,” Med. Phys. 43, 6552. doi:10.1118/1.4967486.

Rippke C. Schrenk O. Renkamp C.K. , et al (2022). “Quality assurance for on-table adaptive magnetic resonance guided radiation therapy: A software tool to complement secondary dose calculation and failure modes discovered in clinical routine,” J. Appl. Clin. Med. Phys. 23, e13523. doi:10.1002/acm2.13523.

Roberts D.A. Sandin C. Vesanen P.T. , et al (2021). “Machine QA for the Elekta Unity system: A report from the Elekta MR-linac consortium,” Med. Phys. 48, e67–e85. doi:10.1002/mp.14764.

Robinson C.G. Samson P.P. Moore K.M.S. , et al (2019). “Phase I/II trial of electrophysiology-guided noninvasive cardiac radioablation for ventricular tachycardia,” Circulation 139, 313–321. doi:10.1161/circulationaha.118.038261.

Rogowski P. von Bestenbostel R. Walter F. , et al (2021). “Feasibility and early clinical experience of online adaptive MR-guided radiotherapy of liver tumors,” Cancers 13, 1523. doi:10.3390/cancers13071523.

Rosenberg S.A. Henke L.E. Shaverdian N. , et al (2019). “A multi-institutional experience of MR-guided liver stereotactic body radiation therapy,” Adv. Radiat. Oncol. 4, 142–149. doi:10.1016/j.adro.2018.08.005.

Rubinstein A.E. Liao Z. Melancon A.D. , et al (2015). “Technical note: A Monte Carlo study of magnetic-field-induced radiation dose effects in mice,” Med. Phys. 42, 5510–5516. doi:10.1118/1.4928600.

Rudra S. Jiang N. Rosenberg S.A. , et al (2019). “Using adaptive magnetic resonance image-guided radiation therapy for treatment of inoperable pancreatic cancer,” Cancer Med. 8, 2123–2132. doi:10.1002/cam4.2100.

Sahin B. Zoto Mustafayev T. Gungor G. , et al (2019). “First 500 fractions delivered with a magnetic resonance-guided radiotherapy system: Initial experience,” Cureus 11, e6457. doi:10.7759/cureus.6457.

Savenije M.H.F. Maspero M. Sikkes G.G. , et al (2020). “Clinical implementation of MRI-based organs-at-risk auto-segmentation with convolutional networks for prostate radiotherapy,” Radiat. Oncol. 15, 104. doi:10.1186/s13014-020-01528-0.

Schellhammer S.M. Gantz S. Lühr A. , et al (2018). “Technical note: Experimental verification of magnetic field-induced beam deflection and Bragg peak displacement for MR-integrated proton therapy,” Med. Phys. 45, 3429–3434. doi:10.1002/mp.12961.

Schwartz D.L. Garden A.S. Thomas J. , et al (2012). “Adaptive radiotherapy for head-and-neck cancer: Initial clinical outcomes from a prospective trial,” Int. J. Radiat. Oncol. Biol. Phys. 83, 986–993. doi:10.1016/j.ijrobp.2011.08.017.

SCoR (2020) MRI Guided Radiotherapy (Society and College of Radiographers, London, UK) https://www.sor.org/learning-advice/professional-body-guidance-and-publications/documents-and-publications/policy-guidance-document-library/mri-guided-radiotherapy

Schweikard A. Shiomi H. Adler J. (2004). “Respiration tracking in radiosurgery,” Med. Phys. 31, 2738–2741. doi:10.1118/1.1774132.

Sgouros G. Bolch W.E. Chiti A. , et al (2021). “ICRU Report 96, dosimetry-guided radiopharmaceutical therapy,” J. ICRU 21, 1–212. doi:10.1177/14736691221141950.

Shi L. Chen Q. Barley S. , et al (2021). “Benchmarking of deformable image registration for multiple anatomic sites using digital data sets with ground-truth deformation vector fields,” Pract. Radiat. Oncol. 11, 404–414. doi:10.1016/j.prro.2021.02.012.

Shortall J. Vasquez Osorio E. Cree A. , et al (2021). “Inter- and intra-fractional stability of rectal gas in pelvic cancer patients during MRIgRT,” Med. Phys. 48, 414–426. doi:10.1002/mp.14586.

Sibolt P. Andersson L.M. Calmels L. , et al (2021). “Clinical implementation of artificial intelligence-driven cone-beam computed tomography-guided online adaptive radiotherapy in the pelvic region,” Phys. Imaging Radiat. Oncol. 17, 1–7. doi:10.1016/j.phro.2020.12.004.

Singhrao K. Fu J. Wu H.H. , et al (2020). “A novel anthropomorphic multimodality phantom for MRI-based radiotherapy quality assurance testing,” Med. Phys. 47, 1443–1451. doi:10.1002/mp.14027.

Smit K. Sjöholm J. Kok J.G. Lagendijk J.J. Raaymakers B.W. (2014). “Relative dosimetry in a 1.5 T magnetic field: An MR-linac compatible prototype scanning water phantom,” Phys. Med. Biol. 59, 4099–4109. doi:10.1088/0031-9155/59/15/4099.

Snyder J.E. St-Aubin J. Yaddanapudi S. , et al (2022). “Reducing MRI-guided radiotherapy planning and delivery times via efficient leaf sequencing and segment shape optimization algorithms,” Phys. Med. Biol. 67, 055005. doi:10.1088/1361-6560/ac5299.

Speight R. Dubec M. Eccles C.L. , et al (2021a). “IPEM topical report: Guidance on the use of MRI for external beam radiotherapy treatment planning,” Phys. Med. Biol. 66, 055025. doi:10.1088/1361-6560/abdc30.

Speight R. Tyyger M. Schmidt M.A. , et al (2021b). “IPEM Topical Report: An international IPEM survey of MRI use for external beam radiotherapy treatment planning,” Phys. Med. Biol. 66, 075007. doi:10.1088/1361-6560/abe9f7.

Spindeldreier C.K. Schrenk O. Bakenecker A. , et al (2017). “Radiation dosimetry in magnetic fields with Farmer-type ionization chambers: Determination of magnetic field correction factors for different magnetic field strengths and field orientations,” Phys. Med. Biol. 62, 6708–6728. doi:10.1088/1361-6560/aa7ae4.

Steinmann A. Alvarez P. Lee H. , et al (2020). “MRIgRT head and neck anthropomorphic QA phantom: Design, development, reproducibility, and feasibility study,” Med. Phys. 47, 604–613. doi:10.1002/mp.13951.

Steinmann A. O’Brien D. Stafford R. , et al (2019). “Investigation of TLD and EBT3 performance under the presence of 1.5T, 0.35T, and 0T magnetic field strengths in MR/CT visible materials,” Med. Phys. 46, 3217–3226. doi:10.1002/mp.13527.

Stemkens B. Paulson E.S. Tijssen R.H.N. (2018). “Nuts and bolts of 4D-MRI for radiotherapy,” Phys. Med. Biol. 63, 21TR01. doi:10.1088/1361-6560/aae56d.

Terpstra M.L. Maspero M. Bruijnen T. , et al (2021). “Real-time 3D motion estimation from undersampled MRI using multi-resolution neural networks,” Med. Phys. 48, 6597–6613. doi:10.1002/mp.15217.

Tetar S.U Bruynzeel A.M.E. Bakker R. , et al (2018). “Patient-reported outcome measurements on the tolerance of magnetic resonance imaging-guided radiation therapy,” Cureus 10, e2236. doi:10.7759/cureus.2236.

Tetar S.U. Bruynzeel A.M.E. Lagerwaard F.J. , et al (2019). “Clinical implementation of magnetic resonance imaging guided adaptive radiotherapy for localized prostate cancer,” Phys. Imaging Radiat. Oncol. 9, 69–76. doi:10.1016/j.phro.2019.02.002.

Thorwarth D. Ege M. Nachbar M. , et al (2020). “Quantitative magnetic resonance imaging on hybrid magnetic resonance linear accelerators: Perspective on technical and clinical validation,” Phys. Imaging Radiat. Oncol. 16, 69–73. doi:10.1016/j.phro.2020.09.007.

Tijssen R.H.N. Philippens M.E.P. Paulson E.S. , et al (2019). “MRI commissioning of 1.5T MR-linac systems: A multi-institutional study,” Radiother. Oncol. 132, 114–120. doi:10.1016/j.radonc.2018.12.011.

Tocco B.R. Kishan A.U. Ma T.M. Kerkmeijer L.G.W. Tree A.C. (2020). “MR-guided radiotherapy for prostate cancer,” Front. Oncol. 10, 616291. doi:10.3389/fonc.2020.616291.

Tree A.C. Khoo V.S. Eeles R.A. , et al (2013). “Stereotactic body radiotherapy for oligometastases,” Lancet Oncol. 14, e28–e37. doi:10.1016/s1470-2045(12)70510-7.

Tyagi N. Fontenla S. Zhang J. , et al (2017). “Dosimetric and workflow evaluation of first commercial synthetic CT software for clinical use in pelvis,” Phys. Med. Biol. 62, 2961–2975. doi:10.1088/1361-6560/aa5452.

van Dams R. Wu T.C. Kishan A.U. , et al (2022). “Ablative radiotherapy for liver tumors using stereotactic MRI-guidance: A prospective phase I trial,” Radiother. Oncol. 170, 14–20. doi:10.1016/j.radonc.2021.06.005.

van de Lindt T.N. Fast M.F. van Kranen S.R. , et al (2019). “MRI-guided mid-position liver radiotherapy: Validation of image processing and registration steps,” Radiother. Oncol. 138, 132–140. doi:10.1016/j.radonc.2019.06.007.

van de Lindt T.N Sonke J.J. Nowee M. , et al (2018). “A self-sorting coronal 4D-MRI method for daily image guidance of liver lesions on an MR-linac,” Int. J. Radiat. Oncol. Biol. Phys. 102, 875–884. doi:10.1016/j.ijrobp.2018.05.029.

van den Wollenberg W. de Ruiter P. Nowee M.E. , et al (2019). “Investigating the impact of patient arm position in an MR-linac on liver SBRT treatment plans,” Med. Phys. 46, 5144–5151. doi:10.1002/mp.13826.

van der Ree M.H. Blanck O. Limpens J. , et al (2020). “Cardiac radioablation—A systematic review,” Heart Rhythm 17, 1381–1392. doi:10.1016/j.hrthm.2020.03.013.

van Heijst T.C. den Hartogh M.D. Lagendijk J.J. van den Bongard H.J. van Asselen B . (2013). “MR-guided breast radiotherapy: Feasibility and magnetic-field impact on skin dose,” Phys. Med. Biol. 58, 5917–5930. doi:10.1088/0031-9155/58/17/5917.

van Houdt P.J. Saeed H. Thorwarth D. , et al (2021a). “Integration of quantitative imaging biomarkers in clinical trials for MR-guided radiotherapy: Conceptual guidance for multicentre studies from the MR-Linac Consortium Imaging Biomarker Working Group,” Eur. J. Cancer. 153, 64–71. doi:10.1016/j.ejca.2021.04.041.

van Houdt P.J. Yang Y. van der Heide U.A . (2021b). “Quantitative magnetic resonance imaging for biological image-guided adaptive radiotherapy,” Front. Oncol. 10, 615643. doi:10.3389/fonc.2020.615643.

van Sörnsen de Koste J.R. Palacios M.A. Bruynzeel A.M.E. , et al (2018). “MR-guided gated stereotactic radiation therapy delivery for lung, adrenal, and pancreatic tumors: A geometric analysis,” Int. J. Radiat. Oncol. Biol. Phys. 102, 858–866. doi:10.1016/j.ijrobp.2018.05.048.

van Timmeren J.E. Chamberlain M. Krayenbuehl J. , et al (2021). “Comparison of beam segment versus full plan re-optimization in daily magnetic resonance imaging-guided online-adaptive radiotherapy,” Phys. Imaging Radiat. Oncol. 17, 43–46. doi:10.1016/j.phro.2021.01.001.

Vasmel J.E. Charaghvandi R.K. Houweling A.C. , et al (2020). “Tumor response after neoadjuvant magnetic resonance guided single ablative dose partial breast irradiation,” Int. J. Radiat. Oncol. Biol. Phys. 106, 821–829. doi:10.1016/j.ijrobp.2019.11.406.

Veiga C. McClelland J. Moinuddin S. , et al (2014). “Toward adaptive radiotherapy for head and neck patients: Feasibility study on using CT-to-CBCT deformable registration for ‘dose of the day’ calculations,” Med. Phys. 41, 031703. doi:10.1118/1.4864240.

Verkooijen H.M. Kerkmeijer L.G.W. Fuller C.D. , et al (2017). “R-IDEAL: A framework for systematic clinical evaluation of technical innovations in radiation oncology,” Front. Oncol. 7, 59. doi:10.3389/fonc.2017.00059.

Vicini F.A. Cecchini R.S. White J.R. , et al (2019). “Long-term primary results of accelerated partial breast irradiation after breast-conserving surgery for early-stage breast cancer: A randomised, phase 3, equivalence trial,” Lancet 394, 2155–2164. doi:10.1016/s0140-6736(19)32514-0.

Videtic G.M. Hu C. Singh A.K. , et al (2015). “A randomized phase 2 study comparing 2 stereotactic body radiation therapy schedules for medically inoperable patients with stage I peripheral non-small cell lung cancer: NRG Oncology RTOG 0915 (NCCTG N0927),” Int. J. Radiat. Oncol. Biol. Phys. 93, 757–764. doi:10.1016/j.ijrobp.2015.07.2260.

Voroney J.P. Brock K.K. Eccles C. Haider M. Dawson L.A. (2006). “Prospective comparison of computed tomography and magnetic resonance imaging for liver cancer delineation using deformable image registration,” Int. J. Radiat. Oncol. Biol. Phys. 66, 780–791. doi:10.1016/j.ijrobp.2006.05.035.

Wang J. Salzillo T. Jiang Y. , et al (2021). “Stability of MRI contrast agents in high-energy radiation of a 1.5T MR-Linac,” Radiother. Oncol. 161, 55–64. doi:10.1016/j.radonc.2021.05.023.

Wang Y. Mazur T.R. Green O. , et al (2016). “A GPU-accelerated Monte Carlo dose calculation platform and its application toward validating an MRI-guided radiation therapy beam model,” Med. Phys. 43, 4040. doi:10.1118/1.4953198.

Weiss E. Hess C.F. (2003). “The impact of gross tumor volume (GTV) and clinical target volume (CTV) definition on the total accuracy in radiotherapy,” Strahlenther. Onkol. 179, 21–30. doi:10.1007/s00066-003-0976-5.

Werensteijn-Honingh A.M. Kroon P.S. Winkel D. , et al (2019). “Feasibility of stereotactic radiotherapy using a 1.5 T MR-linac: Multi-fraction treatment of pelvic lymph node oligometastases,” Radiother. Oncol. 134, 50–54. doi:10.1016/j.radonc.2019.01.024.

Westerhoff J. Daamen L. Christodouleas J. , et al (2022). “Patterns of care and safety in 1800 patients treated on a high-field MR-Linac platform registry,” Radiother. Oncol. 170, S363–S364. doi:10.1016/S0167-8140(22)02555-5.

Westley R. Hall E. Tree A. (2022). “HERMES: Delivery of a speedy prostate cancer treatment,” Clin. Oncol. 34, 426–429. doi:10.1016/j.clon.2022.01.003.

Willigenburg T. de Muinck Keizer D.M. Peters M. , et al (2021). “Evaluation of daily online contour adaptation by radiation therapists for prostate cancer treatment on an MRI-guided linear accelerator,” Clin. Transl. Radiat. Oncol. 27, 50–56. doi:10.1016/j.ctro.2021.01.002.

Winkel D. Bol G.H. Kroon P.S. , et al (2019). “Adaptive radiotherapy: The Elekta Unity MR-linac concept,” Clin. Transl. Radiat. Oncol. 18, 54–59. doi:10.1016/j.ctro.2019.04.001.

Winkel D. Bol G.H. Werensteijn-Honingh A.M. , et al (2020). “Target coverage and dose criteria based evaluation of the first clinical 1.5T MR-linac SBRT treatments of lymph node oligometastases compared with conventional CBCT-linac treatment,” Radiother. Oncol. 146, 118–125. doi:10.1016/j.radonc.2020.02.011.

Witt J.S. Rosenberg S.A. Bassetti M.F. (2020). “MRI-guided adaptive radiotherapy for liver tumours: Visualising the future,” Lancet Oncol. 21, e74–e82. doi:10.1016/s1470-2045(20)30034-6.

Woodings S.J. de Vries J.H.W. Kok J.M.G. , et al (2021). “Acceptance procedure for the linear accelerator component of the 1.5 T MRI-linac,” J. Appl. Clin. Med. Phys. 22, 45–59. doi:10.1002/acm2.13068.

Yadav P. Hallil A. Tewatia D. Dunkerley D.A.P. Paliwal B. (2020). “MOSFET dosimeter characterization in MR-guided radiation therapy (MRgRT) Linac,” J. Appl. Clin. Med. Phys. 21, 127–135. doi:10.1002/acm2.12799.

Yan D. Wong J. Vicini F. , et al (1997). “Adaptive modification of treatment planning to minimize the deleterious effects of treatment setup errors,” Int. J. Radiat. Oncol. Biol. Phys. 38, 197–206. doi:10.1016/s0360-3016(97)00229-0.

Yang Y. Cao M. Sheng K. , et al (2016). “Longitudinal diffusion MRI for treatment response assessment: Preliminary experience using an MRI-guided tri-cobalt 60 radiotherapy system,” Med. Phys. 43, 1369–1373. doi:10.1118/1.4942381.

Yang Y.M. Geurts M. Smilowitz J.B. Sterpin E. Bednarz B.P. (2015). “Monte Carlo simulations of patient dose perturbations in rotational-type radiotherapy due to a transverse magnetic field: A tomotherapy investigation,” Med. Phys. 42, 715–725. doi:10.1118/1.4905168.

Zeidan O.A. Langen K.M. Meeks S.L. , et al (2007). “Evaluation of image-guidance protocols in the treatment of head and neck cancers,” Int. J. Radiat. Oncol. Biol. Phys. 67, 670–677. doi:10.1016/j.ijrobp.2006.09.040.

Zelefsky M.J. Kollmeier M. Cox B. , et al (2012). “Improved clinical outcomes with high-dose image guided radiotherapy compared with non-IGRT for the treatment of clinically localized prostate cancer,” Int. J. Radiat. Oncol. Biol. Phys. 84, 125–129. doi:10.1016/j.ijrobp.2011.11.047.

Ziegenhein P. Pirner S. Ph Kamerling C. Oelfke U. (2015). “Fast CPU-based Monte Carlo simulation for radiotherapy dose calculation,” Phys. Med. Biol. 60, 6097–6111. doi:10.1088/0031-9155/60/15/6097.

Zurl B. Tiefling R. Winkler P. Kindl P. Kapp K.S. (2014). “Hounsfield units variations: Impact on CT-density based conversion tables and their effects on dose distribution,” Strahlenther. Onkol. 190, 88–93. doi:10.1007/s00066-013-0464-5.