Sains Malaysiana 51(4)(2022): 1229-1244

http://doi.org/10.17576/jsm-2022-5104-22

The Occurred Error in Microdosimetry Calculations while Using Water Instead of the Body Organs in Proton Therapy and a New Formula for an Estimate of the Statistical Uncertainty of Microdosimetric Quantities

(Ralat Berlaku dalam Pengiraan Mikrodosimetri semasa Menggunakan Air Bukan Organ Badan dalam Terapi Proton dan Formula Baharu untuk Anggaran Ketidakpastian Statistik Kuantiti Mikrodosimetrik)

SOMAYEH JAHANFAR & HOSSEIN TAVAKOLI-ANBARAN^*

Faculty of Physics and Nuclear Engineering, Shahrood University of Technology, Shahrood, Iran

Received: 4 June 2021/Accepted: 26 August 2021

Abstract

In many experimental and simulation researches, water phantom is used instead of most body organs. Therefore, in this study, we replaced the water phantom instead of some organs to calculate its effect on the proton stopping-power, and range and the consequence of deposited energy and microdosimetric spectra in small sites. Some organs such as the spleen, thyroid, pancreas, prostate, testis, and ovaries are considered. We calculated the proton stopping-power in these organs using the SRIM code. Then using these results, we wrote a program in the programming language of Fortran and computed the proton range and deposited energy in two sites of 1 and 100 micron. Also, using the Geant4-10-4 code, we simulated these sites and obtained microdosimetric spectra of protons at 1 and 5MeV energies. In order to compare different states, the frequency-mean lineal energy, dose-mean lineal energy, these statistical uncertainties and absorb dose in each case were calculated and reported. Also, we estimated the statistical uncertainty of quantities with a new formula. We observed that using water instead of the organs causes a significant error in the calculations of the range and the maximum relative difference percentage of 18% and 22% in deposited energy in 1 and 100 micron sites, respectively. These differences depend on the energy of the incident proton, organ, and size site. Also, this replacement changes microdosimetric spectra, the location, and intensity of the Bragg's peak. The percent difference of location and intensity of the Bragg's peak for water instead of the spleen is -8.66 and 13.42%, respectively. Therefore, using water instead of the body organs in microdosimetry calculations is not recommended.

Keywords: Body organs and water; microdosimetry; proton range and stopping power; proton therapy; statistical uncertainty

Abstrak

Dalam banyak penyelidikan uji kaji dan simulasi, fantom air digunakan sebagai ganti kebanyakan organ tubuh. Oleh itu, dalam kajian ini, kami menggantikan fantom air dan bukannya beberapa organ untuk menghitung kesannya pada daya berhenti proton dan julat serta akibat daripada tenaga dan spektrum mikrodosimetri yang tersimpan di lokasi kecil. Beberapa organ seperti limpa, tiroid, pankreas, prostat, testis dan ovari dipertimbangkan. Kami menghitung daya berhenti proton pada organ-organ ini menggunakan kod SRIM. Kemudian, menggunakan hasil ini, kami menulis sebuah program dalam bahasa pengaturcaraan Fortran dan menghitung julat proton dan menyimpan tenaga di dua lokasi antara 1 dan 100 mikron. Juga, menggunakan kod Geant4-10-4, kami mensimulasi lokasi ini dan memperoleh spektrum mikrodosimetri proton pada tenaga 1 dan 5MeV. Untuk membandingkan keadaan yang berlainan, tenaga linear frekuensi-min, tenaga garis lurus-dosis, ketidakpastian statistik ini dan penyerap dos dalam setiap kes dihitung dan dilaporkan. Kami juga menganggarkan ketidaktentuan statistik kuantiti dengan formula baru. Kami memerhatikan bahawa penggunaan air sebagai ganti organ telah menyebabkan ralat yang ketara dalam pengiraan julat dan peratusan perbezaan relatif maksimum 18% dan 22% tenaga yang tersimpan masing-masing di lokasi 1 dan 100 mikron. Perbezaan ini bergantung pada tenaga proton, organ dan ukuran saiz lokasi. Juga, penggantian ini mengubah spektrum mikrodosimetri, lokasi dan keamatan puncak Bragg. Perbezaan peratus lokasi dan keamatan puncak Bragg untuk air dan bukannya limpa masing-masing adalah -8.66 dan 13.42%. Oleh itu, penggunaan air bukan organ tubuh dalam pengiraan mikrodosimetri tidak digalakkan. 

Kata kunci: Julat proton dan daya berhenti; ketidaktentuan statistik; mikrodosimetri; organ badan dan air; terapi proton

REFERENCES

Ahmadi, O.L. &  Tavakoli-Anbaran, H. 2015. Calculating error percentage in using water phantom instead of soft tissue concerning 103Pd brachytherapy source distribution via Monte Carlo method. Journal of Shahid Sadoughi University of Medical Sciences 23(9): 806-818.

Akiyama, M., Kusunoki, Y. & Umeki, S. 1992. Radiation Research: A Twentieth-Century Perspective Volume II: Congress Proceedings, edited by Dewey, W.C., Edington, M., Michael Fry, R.J., Hall, E.J. & Whitmore, G.F. New York: Academic Press.

Aslam, Prestwich, W.V., McNeill, F.E. & Waker, A.J. 2003. Investigating the TEPC radiation quality factor response for low energy accelerator based clinical applications. Radiation Protection Dosimetry 103(4): 311-322.

Blosser, T.V., Maienschein, F.C. & Freestone, R.M. 1964. The energy deposition in a water-filled spherical phantom by secondaries from high-energy protons and by neutrons. Health Physics 10(10): 743-750.

Bolst, D., Guatelli, S., Tran, L.T., Chartier, L., Lerch, M.L., Matsufuji, N. & Rosenfeld, A.B. 2017. Correction factors to convert microdosimetry measurements in silicon to tissue in 12C ion therapy. Physics in Medicine & Biology 62(6): 2055-2069.

Burigo, L., Pshenichnov, L., Mishustin, I. &  Bleicher,  M. 2013. Microdosimetry of radiation field from a therapeutic 12C beam in water: A study with Geant4 toolkit. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 310: 37-53.

Chattaraj, A., Selvam, T.P. & Datta, D. 2018. Investigation of applicability of pure propane gas for microdosimetry at neutron fields: A Monte Carlo study. Radiation Protection Dosimetry 185(1): 74-86.

Cornelius, I., Rosenfeld, A. & Bradley, P. 2002. Simulations of silicon microdosimetry measurements in fast neutron therapy. Australasian Physical & Engineering Sciences in Medicine 25(4): 168-171.

ICRU. 1983. Microdosimetry. Report 36. USA: International Commission on Radiation Units and Measurements (ICRU).

Jahanfar, S. & Tavakoli-Anbaran, H. 2019. Extracting fairly accurate proton range formulas for use in microdosimetry. Revista Mexicana de Fisica 65(5): 566-572.

Khan, M. & Gibbons, J.P. 2014. Khan's the Physics of Radiation Therapy. 5th ed. New York: Lippincott Williams & Wilkins.

Kliauga, P.J. & Rossi, H. 1982. Studies with encapsulated sources of 125I III. Microdosimetry using a non-metallic wall-less proportional counter. International Journal of Radiation Oncology*Biology*Physics 8(11): 1963-1968.

Lindborg, L. & Waker, A. 2017. Microdosimetry Experimental Methods and Applications. New York: CRC Press.

Liu, L., Prasad, S.C. & Bassano, D.A. 2003. Evaluation of two water-equivalent phantom materials for output calibration of photon and electron beams. Medical Dosimetry 28(4): 267-269.

Mitchell, H.H., Hamilton, T.S., Steggerda, F.R. & Bean, H.W. 1945. The chemical composition of the adult human body and its bearing on the biochemistry of growth. Journal of Biological Chemistry 158(3): 625-637.

Northum, J.D., Guetersloh, S.B. & Braby, L.A. 2012. FLUKA capabilities for microdosimetric analysis. Radiation Research 177(1): 117-123.

Pan, C.Y., Huang, Y.W., Cheng, K.H., Chao, T.C. & Tung, C.J. 2015. Microdosimetry spectra and relative biological effectiveness of 15 and 30 MeV proton beams. Applied Radiation and Isotopes 97: 101-105.

Rasouli, A. & Tavakoli-Anbaran, H. 2018. Estimation of the risk for the second cancers induction in healthy tissues during the radiation therapy of liver’s tumor. Iranian Journal of Radiation Safety and Measurement 6(5): 23-30.

Rasouli, A. & Tavakoli-Anbaran, H. 2017. Study of relation between the gamma flux buildup factors and source geometry by M-C simulation. Nuclear Science and Techniques 28(9): 1-5.

Reniers, B., Vynckier, S. & Verhaegen, F. 2004. Theoretical analysis of microdosimetric spectra and cluster formation for 103Pd and 125I photon emitters. Physics in Medicine & Biology 49(16): 3781-3795.

Rosenfeld, A.B. 2016. Novel detectors for silicon based microdosimetry, their concepts and applications. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 809: 156-170.

Rosenfeld, A.B., Bradley, P.D., Cornelius, I., Kaplan, G.I., Allen, B.J., Flanz, J.B., Goitein, M., Van Meerbeeck, A., Schubert, J., Bailey, J. & Takada, Y. 2000. A new silicon detector for microdosimetry applications in proton therapy. IEEE Transactions on Nuclear Science 47(4): 1386-1394.

Rossi, H.H. & Zaider, M. 2011. Microdosimetry and Its Applications. Berlin: Springer.

Sechopoulos, I.,  Rogers, D.W.O., Bazalova-Carter, M., Bolch, W.E., Heath, E.C., McNitt-Gray, M.F., Sempau, J. & Williamson, J.F. 2018. RECORDS: Improved reporting of Monte Carlo radiation transport studies: Report of the AAPM research committee task group 268. Medical Physics 45(1): e1-e5.

Shahrabi, M. & Tavakoli-Anbaran, H. 2015. Calculating dosimetry parameters in brachytherapy using the continuous beta spectrum of Sm-153 in the Monte Carlo simulation approach. The European Physical Journal Plus 130(2): 1-8.

Thomas, R.H. & Perez-Mendez, V. 1979. Advances in Radiation Protection and Dosimetry in Medicine. 3rd ed. New York: Springer.

Toburen, L.H. & Wilson, W.E. 1977. Energy and angular distributions of electrons ejected from water vapor by 0.3-1.5 MeV protons. The Journal of Chemical Physics 66(11): 5202-5213.

Tsoulfanidis, N. 2015. Measurement and Detection of Radiation. 4th ed. United Kingdom: Taylor & Francis.

Tsuda, S., Sato, T., Takahashi, F., Satoh, D., Endo, A., Sasaki, S., Namito, Y., Iwase, H., Ban, S. & Takada, M. 2010. Measurement of microdosimetric spectra with a wall-less tissue-equivalent proportional counter for a 290 MeV/u12C beam. Physics in Medicine & Biology 55(17): 5089-5101.

Ziegler, J.F. 1999. Stopping of energetic light ions in elemental matter. Journal of Applied Physics 85(3): 1249-1272.

Ziegler, J.F., Ziegler, M.D. & Biersack, J.P. 2008. SRIM – the Stopping and Range of Ions in Matter. Maryland: Library of Congress Cataloging in Publication Data.

^*Corresponding author; email: tavakoli.anbaran@gmail.com