Evaluation of collapsed cone convolution superposition (CCCS) algorithms in prowess treatment planning system for calculating symmetric and asymmetric field size

Tamer Dawod


Purpose: This work investigated the accuracy of prowess treatment planning system (TPS) in dose calculation in a homogenous phantom for symmetric and asymmetric field sizes using collapse cone convolution / superposition algorithm (CCCS).

Methods: The measurements were carried out at source-to-surface distance (SSD) set to 100 cm for 6 and 10 MV photon beams. Data for a full set of measurements for symmetric fields and asymmetric fields, including inplane and crossplane profiles at various depths and percentage depth doses (PDDs) were obtained during measurements on the linear accelerator.

Results: The results showed that the asymmetric collimation dose lead to significant errors (up to approximately 7%) in dose calculations if changes in primary beam intensity and beam quality. It is obvious that the most difference in the isodose curves was found in buildup and the penumbra regions.

Conclusion: The results showed that the dose calculation using Prowess TPS based on CCCS algorithm is generally in excellent agreement with measurements.


Symmetric and Asymmetric Fields; Dose Calculation; Treatment Planning System

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Alaei P, Higgins PD, Gerbi BJ. Implementation of enhanced dynamic wedges in Pinnacle treatment planning system. Med Dosim 2005; 30:228-32.

Jacques R, Taylor R, Wong J, McNutt T. Towards real-time radiation therapy: GPU accelerated superposition/convolution. Comput Methods Programs Biomed 2010; 98:285-92.

Sutter H. The free lunch is over: a fundamental turn toward concurrency in Software. Dr. Dobb’s J 2005, 30.

Petric MP, Clark BG, Robar JL. A comparison of two commercial treatment-planning systems to IMRT. J Appl Clin Med Phys 2005; 6:63-80.

Oyewale S. Dose prediction accuracy of collapsed cone convolution superposition algorithm in a multi-layer inhomogenous phantom. Int J Cancer Ther Oncol 2013; 1:01016.

Das IJ, Ding GX, Ahnesjö A. Small fields: nonequilibrium radiation dosimetry. Med Phys 2008; 35:206-15.

McNutt T. Dose calculations: collapsed cone convolution superposition and delta pixel beam. 2002: Pinnacle White Paper No. 4535 983 02474.

Venselaar J, Welleweerd H. Application of a test package in an intercomparison of the photon dose calculation performance of treatment planning systems used in a clinical setting. Radiotherapy and Oncology 2001; 60:203-13.

El-Attar AL, Abdel-Wanees ME, Hashem MA. Dose measurement and calculation of asymmetric x-ray fields from therapeutic linac. Tenth Radiation Physics & Protection Conference, Egypt, 2010.

Ahnesjö A. Collapsed cone convolution of radiant energy for photon dose calculation in heterogeneous media. Med Phys 1989; 16:577-92.

Moradi F, Mahdavi SR, Mostaar A, Motamedi M. Commissioning and initial acceptance tests for a commercial convolution dose calculation algorithm for radiotherapy treatment planning in comparison with Monte Carlo simulation and measurement. J Med Phys 2012; 37:145-50.

Ayşegül ÜK, Özgehan O, Songül K, et al. Dosimetric verification of prowess panter treatment planning system and the evaluation of the clinical acceptance. Turkish Journal of Oncology 2012; 27:76-82.

Eldesoky I, Attalla EM, Elshemey WM, Zaghloul MS. A comparison of three commercial IMRT treatment planning systems for selected paediatric cases. J Appl Clin Med Phys 2012; 13:3742.

Zhen H, Nelms BE, Tome WA. Moving from gamma passing rates to patient DVH-based QA metrics in pretreatment dose QA. Med Phys 2011; 38:5477-89.

Venselaar J, Welleweerd H, Mijnheer B. Tolerances for the accuracy of photon beam dose calculations of treatment planning systems. Radiother Oncol 2001; 60:191-201.

Van Dyk J, Barnett RB, Cygler JE, Shragge PC. Commissioning and quality assurance of treatment planning computers. Int J Radiat Oncol Biol Phys 1993; 26:261-73.

Sauer O, Nowak G, Richter J. Accuracy of dose calculations of the Philips treatment planning system OSS for blocked fields. Quality assurance in treatment planning. Report from the German task group Proc. Xth ICCR. In: Bruinvis IAD, van der Giessen PH, van Kleffens HJ, Whitkamper FW, editors. The use of computers in radiation therapy. Amsterdam, Elsevier, 1987.

Tahmasebi Birgani MJ, Chegeni N, Zabihzadeh M, Hamzian N. An analytical method to calculate equivalent fields to irregular symmetric and asymmetric photon fields. Med Dosim 2014; 39:54-9.

Chegeni N, Tahmasebi Birgani M J. Equivalent field calculation to irregular symmetric and asymmetric photon fields. International Journal of Medical, Health, Pharmaceutical and Biomedical Engineering 2013; 7.

Chegeni N, Tahmasebi Birgani MJ. Profile calculation in water phantom of symmetric and asymmetric photon beam. World Academy of Science, Engineering and Technology. International Journal of Mathematical, Computational, Physical and Quantum Engineering 2013; 7.

Murugan A, Valas XS, Thayalan K, Ramasubramanian V. Dosimetric evaluation of a three-dimensional treatment planning system. J Med Phys 2011; 36:15-21.

Salk JE. A simple formalism for calculation and verification of dose in asymmetric x-ray fields. Department of Radiotherapy, University of Ulm, D-89081 Ulm, Germany.

Varatharaj C, Ravikumar M, Supe SS, et al. Dosimetric investigation of dual energy photon beams with assymmetric collimator jaws. Pol J Med Phys Eng 2008; 14:33-45.

Hilton J. Capacity-Building for the radiation protection dividend: A twelve point blueprint for strengthening and sustaining the professional radiation protection community in Africa, A Consultation Paper, Nairobi, September 15, 2010.

Rana S, Rogers K, Lee T, Reed D, Biggs C. Dosimetric impact of Acuros XB dose calculation algorithm in prostate cancer treatment using RapidArc. J Cancer Res Ther 2013; 9:430-5.

Ojala J. The accuracy of the Acuros XB algorithm in external beam radiotherapy – a comprehensive review. Int J Cancer Ther Oncol 2014; 2:020417.

Lu L. Dose calculation algorithms in external beam photon radiation therapy. Int J Cancer Ther Oncol 2013; 1:01025.

DOI: http://dx.doi.org/10.14319/ijcto.32.11

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