Initial clinical experience of patient-specific QA of treatment delivery in online adaptive radiotherapy using a 1.5 T MR-Linac

被引：8

作者：

Yang, B. ^{[1
]}

Wong, Y. S. ^{[1
]}

Lam, W. W. ^{[1
]}

Geng, H. ^{[1
]}

Huang, C. Y. ^{[1
]}

Tang, K. K. ^{[1
]}

Law, W. K. ^{[1
]}

Ho, C. C. ^{[1
]}

Nam, P. H. ^{[1
]}

Cheung, K. Y. ^{[1
]}

Yu, S. K. ^{[1
]}

机构：

[1] Hong Kong Sanat & Hosp, Med Phys & Res Dept, Happy Valley, 2 Village Rd, Hong Kong, Peoples R China

来源：

BIOMEDICAL PHYSICS & ENGINEERING EXPRESS | 2021年 / 7卷 / 03期

关键词：

Unity; MR-Linac; quality assurance; online adaptive; ArcCHECK-MR; complexity metric; VOLUMETRIC MODULATED ARC; MAGNETIC-FIELD CORRECTION; CYLINDRICAL DIODE-ARRAY; IONIZATION-CHAMBER; REFERENCE DOSIMETRY; RADIATION-THERAPY; RELATIVE DOSIMETRY; MONTE-CARLO; PERFORMANCE; ARCCHECK;

D O I：

10.1088/2057-1976/abfa80

中图分类号：

R8 [特种医学]; R445 [影像诊断学];

学科分类号：

1002 ; 100207 ; 1009 ;

摘要：

Purpose. This study aims to evaluate the performance of a commercial 1.5 T MR-Linac by analyzing its patient-specific quality assurance (QA) data collected during one full year of clinical operation. Methods and Materials. The patient-specific QA system consisted of offline delivery QA (DQA) and online calculation-based QA. Offline DQA was based on ArcCHECK-MR combined with an ionization chamber. Online QA was performed using RadCalc that calculated and compared the point dose calculation with the treatment planning system (TPS). A total of 24 patients with 189 treatment fractions were enrolled in this study. Gamma analysis was performed and the threshold that encompassed 95% of QA results (T95) was reported. The plan complexity metric was calculated for each plan and compared with the dose measurements to determine whether any correlation existed. Results. All point dose measurements were within 5% deviation. The mean gamma passing rates of the group data were found to be 96.8 +/- 4.0% and 99.6 +/- 0.7% with criteria of 2%/2mm and 3%/3mm, respectively. T95 of 87.4% and 98.2% was reported for the overall group with the two passing criteria, respectively. No statistically significant difference was found between adaptive treatments with adapt-to-position (ATP) and adapt-to-shape (ATS), whilst the category of pelvis data showed a better passing rate than other sites. Online QA gave a mean deviation of 0.2 +/- 2.2%. The plan complexity metric was positively correlated with the mean dose difference whilst the complexity of the ATS cohort had larger variations than the ATP cohort. Conclusions. A patient-specific QA system based on ArcCHECK-MR, solid phantom and ionization chamber has been well established and implemented for validation of treatment delivery of a 1.5 T MR-Linac. Our QA data obtained over one year confirms that good agreement between TPS calculation and treatment delivery was achieved.

引用

页数：9

共 37 条

[21] Volumetric modulated arc therapy: IMRT in a single gantry arc [J].

Otto, Karl .

MEDICAL PHYSICS, 2008, 35 (01) :310-317

[22] New developments in arc radiation therapy: A review [J].

Palma, David A. ;

Verbakel, Wilko F. A. R. ;

Otto, Karl ;

Senan, Suresh .

CANCER TREATMENT REVIEWS, 2010, 36 (05) :393-399

[23] A protocol for EBT3 radiochromic film dosimetry using reflection scanning [J].

Papaconstadopoulos, Pavlos ;

Hegyi, Gyorgy ;

Seuntjens, Jan ;

Devic, Slobodan .

MEDICAL PHYSICS, 2014, 41 (12)

[24] Dosimetric performance of the Elekta Unity MR-linac system: 2D and 3D dosimetry in anthropomorphic inhomogeneous geometry [J].

Pappas, E. ;

Kalaitzakis, G. ;

Boursianis, T. ;

Zoros, E. ;

Zourari, K. ;

Pappas, E. P. ;

Makris, D. ;

Seimenis, I ;

Efstathopoulos, E. ;

Maris, T. G. .

PHYSICS IN MEDICINE AND BIOLOGY, 2019, 64 (22)

[25] Magnetic Resonance Imaging-Guided Adaptive Radiation Therapy: A "Game Changer" for Prostate Treatment? [J].

Pathmanathan, Angela U. ;

van As, Nicholas J. ;

Kerkmeijer, Linda G. W. ;

Christodouleas, John ;

Lawton, Colleen A. F. ;

Vesprini, Danny ;

van der Heide, Uulke A. ;

Frank, Steven J. ;

Nill, Simeon ;

Oelfke, Uwe ;

van Herk, Marcel ;

Li, X. Allen ;

Mittauer, Kathryn ;

Ritter, Mark ;

Choudhury, Ananya ;

Tree, Alison C. .

INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS, 2018, 100 (02) :361-373

[26] Ionization chamber correction factors for MR-linacs [J].

Pojtinger, Stefan ;

Dohm, Oliver Steffen ;

Kapsch, Ralf-Peter ;

Thorwarth, Daniela .

PHYSICS IN MEDICINE AND BIOLOGY, 2018, 63 (11)

[27] First patients treated with a 1.5 T MRI-Linac: clinical proof of concept of a high-precision, high-field MRI guided radiotherapy treatment [J].

Raaymakers, B. W. ;

Jurgenliemk-Schulz, I. M. ;

Bol, G. H. ;

Glitzner, M. ;

Kotte, A. N. T. J. ;

van Asselen, B. ;

de Boer, J. C. J. ;

Bluemink, J. J. ;

Hackett, S. L. ;

Moerland, M. A. ;

Woodings, S. J. ;

Wolthaus, J. W. H. ;

van Zijp, H. M. ;

Philippens, M. E. P. ;

Tijssen, R. ;

Kok, J. G. M. ;

de Groot-van Breugel, E. N. ;

Kiekebosch, I. ;

Meijers, L. T. C. ;

Nomden, C. N. ;

Sikkes, G. G. ;

Doornaert, P. A. H. ;

Eppinga, W. S. C. ;

Kasperts, N. ;

Kerkmeijer, L. G. W. ;

Tersteeg, J. H. A. ;

Brown, K. J. ;

Pais, B. ;

Woodhead, P. ;

Lagendijk, J. J. W. .

PHYSICS IN MEDICINE AND BIOLOGY, 2017, 62 (23) :L41-L50

[28] Relative dosimetry in a 1.5 T magnetic field: an MR-linac compatible prototype scanning water phantom [J].

Smit, K. ;

Sjoholm, J. ;

Kok, J. G. M. ;

Lagendijk, J. J. W. ;

Raaymakers, B. W. .

PHYSICS IN MEDICINE AND BIOLOGY, 2014, 59 (15) :4099-4109

[29] Performance of a multi-axis ionization chamber array in a 1.5 T magnetic field [J].

Smit, K. ;

Kok, J. G. M. ;

Lagendijk, J. J. W. ;

Raaymakers, B. W. .

PHYSICS IN MEDICINE AND BIOLOGY, 2014, 59 (07) :1845-1855

[30] Towards reference dosimetry for the MR-linac: magnetic field correction of the ionization chamber reading [J].

Smit, K. ;

van Asselen, B. ;

Kok, J. G. M. ;

Aalbers, A. H. L. ;

Lagendijk, J. J. W. ;

Raaymakers, B. W. .

PHYSICS IN MEDICINE AND BIOLOGY, 2013, 58 (17) :5945-5957

← 1 2 3 4 →