Performance Characteristics of an Independent Dose Verification Program for Helical Tomotherapy

Overview

Journal J Med Phys

Date 2017 Oct 5

PMID 28974862

Citations 1

Authors

Isaac C F Chang

Jeff Chen

Slav Yartsev

Affiliations

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Abstract

Helical tomotherapy with its advanced method of intensity-modulated radiation therapy delivery has been used clinically for over 20 years. The standard delivery quality assurance procedure to measure the accuracy of delivered radiation dose from each treatment plan to a phantom is time-consuming. RadCalc, a radiotherapy dose verification software, has released specifically for beta testing a module for tomotherapy plan dose calculations. RadCalc's accuracy for tomotherapy dose calculations was evaluated through examination of point doses in ten lung and ten prostate clinical plans. Doses calculated by the TomoHDA™ tomotherapy treatment planning system were used as the baseline. For lung cases, RadCalc overestimated point doses in the lung by an average of 13%. Doses within the spinal cord and esophagus were overestimated by 10%. Prostate plans showed better agreement, with overestimations of 6% in the prostate, bladder, and rectum. The systematic overestimation likely resulted from limitations of the pencil beam dose calculation algorithm implemented by RadCalc. Limitations were more severe in areas of greater inhomogeneity and less prominent in regions of homogeneity with densities closer to 1 g/cm. Recommendations for RadCalc dose calculation algorithms and anatomical representation were provided based on the results of the study.

Citing Articles

Evaluation and Validation of IBA I'MatriXX Array for Patient-Specific Quality Assurance of TomoTherapy.

Sresty N, Raju A, Reddy B, Sahithya V, Mohmd Y, Kumar G J Med Phys. 2019; 44(3):222-227.

PMID: 31576071 PMC: 6764175. DOI: 10.4103/jmp.JMP_11_19.

References

Chen Q, Lu W, Chen Y, Chen M, Henderson D, Sterpin E . Validation of GPU based TomoTherapy dose calculation engine. Med Phys. 2012; 39(4):1877-86. DOI: 10.1118/1.3693057. View

Gibbons J, Smith K, Cheek D, Rosen I . Independent calculation of dose from a helical TomoTherapy unit. J Appl Clin Med Phys. 2009; 10(1):103-119. PMC: 5720509. DOI: 10.1120/jacmp.v10i1.2772. View

Thomas S, Eyre K, Tudor G, Fairfoul J . Dose calculation software for helical tomotherapy, utilizing patient CT data to calculate an independent three-dimensional dose cube. Med Phys. 2012; 39(1):160-7. DOI: 10.1118/1.3668061. View

Wang L, Yorke E, Chui C . Monte Carlo evaluation of 6 MV intensity modulated radiotherapy plans for head and neck and lung treatments. Med Phys. 2002; 29(11):2705-17. DOI: 10.1118/1.1517291. View

Zhao Y, Mackenzie M, Kirkby C, Fallone B . Monte Carlo evaluation of a treatment planning system for helical tomotherapy in an anthropomorphic heterogeneous phantom and for clinical treatment plans. Med Phys. 2009; 35(12):5366-74. DOI: 10.1118/1.3002316. View

Welsh J, Patel R, Ritter M, Harari P, Mackie T, Mehta M . Helical tomotherapy: an innovative technology and approach to radiation therapy. Technol Cancer Res Treat. 2003; 1(4):311-6. DOI: 10.1177/153303460200100413. View

Knoos T, Ahnesjo A, Nilsson P, Weber L . Limitations of a pencil beam approach to photon dose calculations in lung tissue. Phys Med Biol. 1995; 40(9):1411-20. DOI: 10.1088/0031-9155/40/9/002. View

Aarup L, Nahum A, Zacharatou C, Juhler-Nottrup T, Knoos T, Nystrom H . The effect of different lung densities on the accuracy of various radiotherapy dose calculation methods: implications for tumour coverage. Radiother Oncol. 2009; 91(3):405-14. DOI: 10.1016/j.radonc.2009.01.008. View

Mackie T, Balog J, Ruchala K, Shepard D, Aldridge S, Fitchard E . Tomotherapy. Semin Radiat Oncol. 1999; 9(1):108-17. DOI: 10.1016/s1053-4296(99)80058-7. View

10.

Langen K, Papanikolaou N, Balog J, Crilly R, Followill D, Goddu S . QA for helical tomotherapy: report of the AAPM Task Group 148. Med Phys. 2010; 37(9):4817-53. DOI: 10.1118/1.3462971. View

11.

Sterpin E, Salvat F, Olivera G, Vynckier S . Monte Carlo evaluation of the convolution/superposition algorithm of Hi-Art tomotherapy in heterogeneous phantoms and clinical cases. Med Phys. 2009; 36(5):1566-75. DOI: 10.1118/1.3112364. View

12.

Lax I, Panettieri V, Wennberg B, Duch M, Naslund I, Baumann P . Dose distributions in SBRT of lung tumors: Comparison between two different treatment planning algorithms and Monte-Carlo simulation including breathing motions. Acta Oncol. 2006; 45(7):978-88. DOI: 10.1080/02841860600900050. View

13.

Neilson C, Klein M, Barnett R, Yartsev S . Delivery quality assurance with ArcCHECK. Med Dosim. 2012; 38(1):77-80. DOI: 10.1016/j.meddos.2012.07.004. View

14.

Haslam J, Bonta D, Lujan A, Rash C, Jackson W, Roeske J . Comparison of dose calculated by an intensity modulated radiotherapy treatment planning system and an independent monitor unit verification program. J Appl Clin Med Phys. 2003; 4(3):224-30. PMC: 5724446. DOI: 10.1120/jacmp.v4i3.2519. View

15.

Balog J, Holmes T, Vaden R . A helical tomotherapy dynamic quality assurance. Med Phys. 2006; 33(10):3939-50. DOI: 10.1118/1.2351952. View