Interpretation of Gamma Index for Quality Assurance of Simultaneously Integrated Boost (SIB) IMRT Plans for Head and Neck Carcinoma

• Autorzy: Atiq, M. , Atiq, A. , Iqbal, K. , Shamsi, Q. , Andleeb, F. , Buzdar, S. A.
• Języki publikacji: EN

Abstrakty

EN

Objective: The Gamma Index is prerequisite to estimate point-by-point difference between measured and calculated dose distribution in terms of both Distance to Agreement (DTA) and Dose Difference (DD). This study aims to inquire what percentage of pixels passing a certain criteria assure a good quality plan and suggest gamma index as efficient mechanism for dose verification of Simultaneous Integrated Boost Intensity Modulated Radiotherapy plans. Method: In this study, dose was calculated for 14 head and neck patients and IMRT Quality Assurance was performed with portal dosimetry using the Eclipse treatment planning system. Eclipse software has a Gamma analysis function to compare measured and calculated dose distribution. Plans of this study were deemed acceptable when passing rate was 95% using tolerance for Distance to agreement (DTA) as 3mm and Dose Difference (DD) as 5%. Result and Conclusion: Thirteen cases pass tolerance criteria of 95% set by our institution. Confidence Limit for DD is 9.3% and for gamma criteria our local CL came out to be 2.0% (i.e., 98.0% passing). Lack of correlation was found between DD and γ passing rate with R² of 0.0509. Our findings underline the importance of gamma analysis method to predict the quality of dose calculation. Passing rate of 95% is achieved in 93% of cases which is adequate level of accuracy for analyzed plans thus assuring the robustness of SIB IMRT treatment technique. This study can be extended to investigate gamma criteria of 5%/3mm for different tumor localities and to explore confidence limit on target volumes of small extent and simple geometry.

Słowa kluczowe

EN

simultaneous integrated boost SIB; distance to agreement DTA; dose difference DD; portal dosimetry; quality assurance; QA; head and neck

• Czasopismo: Polish Journal of Medical Physics and Engineering
• Rocznik: 2017
• Tom: Vol. 23, Iss. 4
• Strony: 93--97
• Opis fizyczny: Bibliogr. 31 poz., rys., tab.

Twórcy

autor

Atiq, M.

• Department of Physics, The Islamia University of Bahawalpur

autor

Atiq, A.

• Department of Physics, The Islamia University of Bahawalpur,

autor

Iqbal, K.

• Shaukat Khanum Memorial cancer hospital & research center Lahore Pakistan

autor

Shamsi, Q.

• Department of Physics, The Islamia University of Bahawalpur

autor

Andleeb, F.

• Department of Physics, The Islamia University of Bahawalpur

autor

Buzdar, S. A.

• Department of Physics, The Islamia University of Bahawalpur

Bibliografia

• [1] Kouloulias V, Antypas C, Liakouli Z, et al. The first implementation of IMRT technique for head & neck and prostate cancer patients in public sector in Greece: feasibility, treatment planning and dose delivery verification using the delta (4PT) Pre-Treatment volumetric quality assurance system. J BUON. 2014;20(1):196-205.
• [2] Roxby KJ, Crosbie JC. Pre-treatment verification of intensity modulated radiation therapy plans using a commercial electronic portal dosimetry system. Australas Phys Eng Sci Med. 2010;33(1):51-57.
• [3] Franceschini D, Paiar F, Meattini I, et al. Simultaneous integrated boost–intensity‐modulated radiotherapy in head and neck cancer. Laryngoscope. 2013;123(12):E97-103.
• [4] Mohan R, Wu Q, Manning M, Schmidt-Ullrich R. Radiobiological considerations in the design of fractionation strategies for intensity-modulated radiation therapy of head and neck cancers. Int J Radiat Oncol Biol Phys. 2000;46(3):619-630.
• [5] Krishnan J, Rao S, Hegde S, Shetty J. A Dosimetric Comparison of Double Arc Volumetric Modulated Arc Therapy with Large Field Intensity Modulated Radiation Therapy for Head and Neck Cancer. IJMPCERO. 2015;4(4):353-363.
• [6] Suzuki M, Nakamatsu K, Kanamori S, et al. Feasibility study of the simultaneous integrated boost (SIB) method for malignant gliomas using intensity-modulated radiotherapy (IMRT). Jpn J Clin Oncol. 2003;33(6):271-277.
• [7] Elawady RA, Attalla EM, Elshemey WM, et al. Dose verification of intensity modulated radiotherapy in head and neck tumors. Int J Cancer Ther Oncol. 2014;2(3):02037.
• [8] Agazaryan N, Solberg TD, DeMarco JJ. Patient specific quality assurance for the delivery of intensity modulated radiotherapy. J Appl Clin Med Phys. 2003;4(1):40-50.
• [9] Depuydt T, Van Esch A, Huyskens DP. A quantitative evaluation of IMRT dose distributions: refinement and clinical assessment of the gamma evaluation. Radiother Oncol. 2002;62(3):309-319.
• [10] Low DA, Dempsey JF. Evaluation of the gamma dose distribution comparison method. Med Phys. 2003;30(9):2455-2464.
• [11] Mijheer B, Georg D. Guidelines for the verification of IMRT. Brussels, Belgium: ESTRO; 2008.
• [12] Ezzell GA, Burmeister JW, Dogan N, et al. IMRT commissioning: multiple institution planning and dosimetry comparisons, a report from AAPM Task Group 119. Med Phys. 2009;36(11):5359-5373.
• [13] Tonigan JR. Evaluation of intensity modulated radiation therapy (IMRT) delivery error due to IMRT treatment plan complexity and improperly matched dosimetry data. MSc Thesis. The University of Texas. Houston, Texas; 2011.
• [14] Varatharaj C, Ravikumar M, Sathiyan S, et al. Dosimetric verification of brain and head and neck intensity-modulated radiation therapy treatment using EDR2 films and 2D ion chamber array matrix. J Cancer Res Ther. 2010;6(2):179-184.
• [15] Stasi M, Bresciani S, Miranti A, et al. Pretreatment patient‐specific IMRT quality assurance: A correlation study between gamma index and patient clinical dose volume histogram. Med Phys. 2012;39(12):7626-7634.
• [16] Caivano R, Califano G, Fiorentino A, et al. Clinically relevant quality assurance for intensity modulated radiotherapy plans: gamma maps and DVH-based evaluation. Cancer Invest. 2014;32(3):85-91.
• [17] Li H, Dong L, Zhang L, et al. Toward a better understanding of the gamma index: Investigation of parameters with a surface‐based distance method. Med Phys. 2011;38(12):6730-6741.
• [18] Molineu A, Followill DS, Balter PA, et al. Design and implementation of an anthropomorphic quality assurance phantom for intensity-modulated radiation therapy for the Radiation Therapy Oncology Group. Int J Radiat Oncol Biol Phys. 2005;63(2):577-583.
• [19] Grégoire V, Mackie TR. State of the art on dose prescription, reporting and recording in Intensity-Modulated Radiation Therapy (ICRU report No. 83). Cancer Radiother. 2011;15(6-7):555-559.
• [20] Chaikh A, Desgranges C, Balosso J. Statistical methods to evaluate the correlation between measured and calculated dose using quality assurance method in IMRT. Int J Cancer Ther Oncol. 2015;3(4):
• [21] Stock M, Kroupa B, Georg D. Interpretation and evaluation of the γ index and the γ index angle for the verification of IMRT hybrid plans. Phys Med Biol. 2005;50(3):399-411.
• [22] Chung JB, Kim JS, Ha SW, Ye SJ. Statistical analysis of IMRT dosimetry quality assurance measurements for local delivery guideline. Radiat Oncol. 2011;6(1):27.
• [23] Howell RM, Smith IP, Jarrio CS. Establishing action levels for EPID-based QA for IMRT. J Appl Clin Med Phys.2008;9(3):16-25.
• [24] van Zijtveld M, Dirkx ML, de Boer HC, Heijmen BJ. Dosimetric pre-treatment verification of IMRT using an EPID; clinical experience. Radiother Oncol. 2006;81(2):168-175.
• [25] Childress NL, White RA, Bloch C, et al. Retrospective analysis of 2D patient‐specific IMRT verifications. Med Phys. 2005;32(4):838-850.
• [26] Fraass B, Doppke K, Hunt M, et al. American Association of Physicists in Medicine Radiation Therapy Committee Task Group 53: quality assurance for clinical radiotherapy treatment planning. Med Phys. 1998;25(10):1773-1829.
• [27] Jang SY, Liu HH, Mohan R. Underestimation of low-dose radiation in treatment planning of intensity-modulated radiotherapy. Int J Radiat Oncol Biol Phys. 2008;71(5):1537-1546.
• [28] Deng J, Pawlicki T, Chen Y, et al. The MLC tongue-and-groove effect on IMRT dose distributions. Phys Med Biol. 2001;46(4):1039-1060
• [29] Li JS, Lin T, Chen L, et al. Uncertainties in IMRT dosimetry. Med Phys. 2010;37(6):2491-2500.
• [30] Das IJ, Ding GX, Ahnesjö A. Small fields: nonequilibrium radiation dosimetry. Med Phys. 2008;35(1):206-215.
• [31] Ceberg C. A note on the interpretation of the gamma evaluation index. Journal of Physics: Conference Series. 2013;(444)1:012082.

Identyfikatory

DOI

10.1515/pjmpe-2017-0016