Pencil Beam and Collapsed Cone Algorithm Calculations for a Lung-Type Volume Using Ct and the Omp Treatment Planning System

Pencil Beam and Collapsed Cone Algorithm Calculations for a
Lung-type Volume Using CT and the OMP Treatment Planning System
Methods
Measurements have been carried out in both phantom and a specifically designed phantom which simulated human lung volume. Samples were taken from the Lung Planning CT images for 15 patients using the Oncentra Masterplan OMP Treatment Planning System. The X-axis was, following convention, taken to be horizontal, and the Y-axis to be vertical; accordingly, abscissa and ordinate distances to the skin, heart and the lungs were measured (see figure 8). Figures 4 and 5 show typical CT images for a patient’s lungs, while Tables 1 and 2 give the beam information and dose information for typical patients. The X-ray images were taken using CT-SIM: Philips Brilliance Big Bore. A print out of the planning CT images was produced by the Oncentra Masterplan OMP treatment Planning system (see section 3.3).

Figure 4: Lungs Image for Patient by CT-SIM: Philips Brilliance Big Bore Beam Information | Beam | 1ANT | 2RPO | 3RPO | 4ARO | Nom. Acc. Pot.(MV or MeV) | 6 | 6 | 6 | 6 | FX (cm) | 8.2 | 8.2 | 8.6 | 8.6 | FY (cm) | 9.4 | 10.6 | 8.2 | 8.6 | SSD (cm) | 87.2 | 86.8 | 85.6 | 84.7 | Gantry (degrees) | 0 | 223 | 267 | 320 | Wedge Angle(degrees) | 60/60 | 60/33 | 60/25 | | Dose Information: Absolute dose 5500 cGy (275 cGy / fraction) | Number of Fraction | 20 | 20 | 20 | 20 | MU or min / Fraction | IN = 424.77OUT = 0 | IN = 185.78OUT = 85.22 | IN = 92.85OUT = 69.34 | 16.39 |
Table 1: Beam Information and Dose Information for Patient

Figure 5: Lungs Image for Patient by CT-SIM: Philips Brilliance Big Bore

Beam Information | Beam | 3LPO THORAX | 4ANT | 5MINI-ANT | 6LAO | Nom. Acc. Pot.(MV or MeV) | 6 | 6 | 6 | 6 | FX (cm) | 10.6 | 10.1 | 9.7 | 14.2 | FY (cm) | 9.7 | 14.3 | 11 | 10.1 | SSD (cm) | 86.3 | 87.2 | 87.2 | 82.4 | Gantry (degrees) | 120 | 0 | 0 | 60 | Wedge Angle(degrees) | 60/25 | 60/28 |

References: [1] Ang, K. & Garden, A. S. 2006. Radiotherapy for Head and Neck Cancers: Indications and Techniques. United States: Lippincott Williams & Wilkins [2] Arnfield, MR, CH Siantar, J [3] Aspradakis, M., McCallum, H. M. and Wilson, N. 2006. Dosimetric and Treatment Planning Considerations for Radiotheraphy of the Chest Wall. The British Journal of Radiology, 79 (2006), 828-836 [4] Chetty, IJ, B [5] Chin, L. & Regine, W. 2008. Principles and Practice of Stereotactic Radiosurgery. United States: Springer Science+Business Media, LLC [6] Cox, J [7] Fotina, Winkler, Kunzler, Reiterer, Simmat and Georg (2009). Advanced Kernel Methods VS. Monte Carlo-based Dose Calculation for High Energy Photon Beams. Radiotherapy and Oncology. 93 (2009) 645-653 [8] Hasenbalg, F., Neuenschwander, H., Mini, R [9] Khan, F. 2010. The Physics of Radiation Therapy. Philadelphia: Lippincott Williams & Wilkins, a Wolters Kluwer Business [10] Krieger, T [11] Li, A. (2011). Adaptive Radiation Therapy. United States: Taylor and Francis Group, LLC [12] McGarry, C., O’Toole, M [13] Papanikolaou, N. and Stathakis, S. 2009. Dose-calculation Algorithms in the Context of Inhomogeneity Corrections for High energy Photon Beams. Texas: University of Texas Health Sciences Center [14] Rong, Y [15] Schmitter, M. (2007). The Study and Analysis of Heterogeneity Correction Algorithms Used in the Delivery of Step and Shoot and Sliding Window IMRT. United States: ProQuest [16] Schulz, R [17] Small, W. 2008. Combining Targeted Biological Agents with Radiotherapy: Current Status and Future Directions. United States: Demos Medical Publishing, LLC. [18] Spirydovich, S. 2006. Evaluation of Dose Distribution for Targets Near Inhomogeneities in Photon Beam Radiation Therapy. United States: ProQuest Information and Learning Company [19] Tyagi, N., A [20] Vanderstraeten, B., W. Duthoy, W. De Gersem, W. De Neve, and H. Thierens. 2006. [18f] Fluro-deoxy-glucose Positron Emission Tomography ([18F]FDG-PET) [21] Yue, X [22] Ahnesjo, A. 1989. Collapsed cone convolution of radiant energy for photon dose calculation in heterogeneous media. Medical Physics. 16(4): 577-592. [23] Thomas, S. 2009. Treatment planning algorithms: Photon and Electron calculations. Scope, 18(1). pp. 21-27. [24] Buzdar, S. A., Afzal, M. and Todd-Pokropek, A. 2010. Comparison of pencil beam and collapsed cone algorithms, in radiotherapy treatment planning for 6 and 10 mv photon. J Ayub Med Coll Abbottabad. 22(3), 152:154. [25] Dobler, B. et al. 2006. Optimization of extracranial stereotactic radiation therapy of small lung lesions using accurate dose calculation algorithms. Radiation Oncology. 1(45). [29] Jemal, A., Siegel, R., Ward, E., Murray, T., Xu, J. and Thun, M. J., 2007. Cancer Statistics, 2007. CA: A Cancer Journal for clinicians. 57:43-66 [30] Shiu, A, S., Hogstrom, K, R [37] A Aspradakis, M. M., Morrison, R. H., Richmond, N. D. & Steele, A., 2003. Experimental verification of convolution/superposition photon dose calculations for radiotherapy treatment planning. Physics in Medicine and Biology, (48)17. pp. 2873-2893. [38] Almond, P. et al., 1999. AAPM’s TG-51 protocol for clinical reference dosimetry of high-energy photon and electron beams. Journal of Medical Physics, 26(9). pp. 1847-1870. [39] Fippel, M., 1999. Fast Monte Carlo dose calculations for photon beams based on the vmc electron algorithm Medical Physics, 26. pp. 1466–75. [40] Haryanto, F., Fippel, M., Bakai, A. et al., 2004. Study on the tongue and groove effect of the Elekta multileaf collimator using Monte Carlo simulation and film dosimetry. Strahlenther Onkol, 180. pp. 57–61. [41] Heintz, B., Hammond, D., Cavanaugh, D. & Rosencranz, D., 2006. SU‐FF‐T‐09: A Comparison of MatriXX, MapCHECK and Film for IMRT QA: Limitations of 2D Electronic Systems. Medical Physics, 33(6). pp. 2052-2054. [42] Korreman, S. S., Pedersen, A. N., Nottrup, T. J., Specht, L. & Nystrom, H., 2005. Breathing adapted radiotherapy for breast cancer: comparison of free breathing gating with the breath-hold technique. Radiother Oncol, 76. pp. 311–8. [43] Muir, B. R. & Rogers, D. W. O., 2010. Monte Carlo calculations of kQ, the beam quality conversion factor. Medical Physics, 37. pp. 5939-5950. [44] Pallotta, S., Marrazzo, L [45] Pedersen, A. N., Korreman, S., Nystrom, H. & Specht, L., 2004. Breathing adapted radiotherapy of breast cancer: reduction of cardiac and pulmonary doses using voluntary inspiration breathhold. Radiother Oncol, 72. pp. 53–60. [47] White, D.R., Martin, R.J. & Darlison, R., 1977. Epoxy resin based tissue substitutes. The British Journal of Radiology, 50(599). pp. 814–821. [48] Wilkinson, M. & Aspradakis, M.M., 2004. A study of electronic compensation methods in breast radiotherapy planning. In: IPEM Annual Scientific Meeting. York, UK: IPEM. Radiology, 2002. 75: p. 56–58.