Abstract
For the clinical applications of electron beams, the physical behavior of electrons has to be well understood. In this chapter, we discuss the fundamental features of electron transport and theways in which they influence the dose distribution patterns. Electrons are more complex than photons in their transport behavior. The dose distribution for electron beams can be well documented for standard conditions of a beam incident on a unit-density medium with a flat surface. For nonstandard situations that may be encountered in actual clinical contexts, the interpretation and prediction of electron beam dose distributions pose many challenges.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Moliere, G., Theorie der Streuung schneller geladener Teilchen II, Mehrfach-und Vielfachstreuung, Z. Naturforsch., Vol. 3a, p78–97, 1948.
Bethe, H.A., Rose, M.E., and Smith, L.P., The multiple scattering of electrons, Proc. Am. Philos. Soc., Vol. 78, p573–585, 1938.
Heitler, W., The Quantum Theory of Radiation, Third Edition, p414, Oxford University Press, London, 1954.
Scott, W.T., The theory of small-angle multiple scattering of fast charged particles, Rev. Mod. Phys., Vol. 35, p2–313, 1963.
Lanzl, L.H., Fundamental interactions of electrons with water, p21–24, in Proceedings of the Symposium on Electron Dosimetry and Arc Therapy, Paliwal, B. (Ed.), American Institute of Physics, New York, 1982.
Lanzl, L.H., Electron pencil beam scanning and its application in radiation therapy, p55–66, in Frontiers of Radiation Therapy, Oncology, Vol. 2, Karger, Basel, 1968.
Mandour, M.A., and Harder, D., Systematic optimization of the double scatterer system for electron beam field flattening, Strahlentherapie, Vol. 154, p328–322, 1978.
Lax, I., and Brahme, A., On the collimation of high energy electron beams, Acta Radiol. Oncol., Vol. 19, p199–207, 1980.
Markus, B., Energie-Bestimmung schneller Elektronen auf Tiefendosiskurven, Strahlentherapie, Vol. 116, p280–286, 1961.
Perry, D.J., and Holt, J.G., A model for calculating the effects of small inhomogeneities on electron beam dose distributions, Med. Phys., Vol. 7, p207–215, 1980.
Hogstrom, K.R., and Mills, M.D., Electron beam dose calculations, Phys. Med. Biol., Vol. 26, p445–459, 1981.
Werner, B.L., Khan, F.M., and Diebel, F.C., Model for calculating electron beam scattering in treatment planning, Med. Phys., Vol. 9, p180–187, 1982.
Jette, D., Pagnamenta, A., Lanzl, L.H., and Rozenfeld, M., The application of multiple scattering theory to therapeutic electron dosimetry, Med. Phys., Vol. 10, p141–146, 1983.
Storchi, P.R.M., and Huizenga, H., On anumerical approach of the pencil beam model, Phys. Med. Biol., Vol. 30, p467–473, 1985.
Kirsner, S.M., Hogstrom, K.R., Kurup, R.G., and Moyers, M.F., Dosimetric evaluation in heterogeneous tissue of anterior electron beam irradiation for treatment of retinoblastoma, Med. Phys., Vol. 14, p772–779, 1987.
Lax, I., Brahme, A., and Andreo, P., Electron beam dose planning using Gaussian beams, Acta Radiol. Suppl., 364, Vol. 36, p49–59, 1983.
McParland, B.J., Cunningham, J.R., and Woo, M.K., The optimization of pencil beam widths for use in an electron pencil beam algorithm, Med. Phys., Vol. 14, p489–497, 1988.
Jette, D., Electron dose calculation using multiple-scattering theory. A Gaussian multiple-scattering theory, Med. Phys., Vol. 15, p123–137, 1988.
Jette, D., Lanzl, L.H., Pagnamenta, A., Rozenfeld, M., Bernard, D., Kao, M., and Sabbas, A.M., Electron dose calculation using multiple scattering theory: Thin planar inhomogeneities, Med. Phys., Vol. 16, p712–725, 1989.
Huizenga, H., and Storchi, P.R.M., Numerical calculations of energy deposition of broad high energy electron beams, Phys. Med. Biol., Vol. 34, p1371–1396, 1989; Corrigendum, Phys. Med. Biol., Vol. 35, 1445, 1990.
Jette, D., Electron dose calculation using multiple-scattering theory: Localized inhomogeneities — a new theory, Med. Phys., Vol. 18, p123–132, 1991.
McLellan, J., Sandison, G.A., Papiez, L., and Huda, W., A restricted angular scattering model for electron penetration in dense media, Med. Phys., Vol. 18, p1–6, 1991.
Shiu, A.S., and Hogstrom, K.R., Pencilbeamredefinitionalgorithm for electron dose distributions, Med. Phys., Vol. 18, p7–18, 1991.
Jette, D., and Walker, S., Electron beam dose calculation using multiple scattering theory: Evaluation of a new model for inhomogeneities, Med. Phys., Vol. 19, p1241–1254, 1992.
Petti, P.L., Differential pencil beam dose calculation for charged particles, Med. Phys., Vol. 19, p137–149, 1992.
Al-Beteri, A.A., and Raeside, D.E., Optimal electron beam treatment planning for retinoblastoma using a new three-dimensional Monte Carlo based treatment planning system, Med. Phys., Vol 19, p125–135, 1992.
Ma, C.M., and Jiang, S.B., Monte Carlo modeling of electron beams from medical accelerator, Phys. Med. Biol., Vol.44, pp R157–189, 1999.
Morawska-Kaczynska, M., and Huizenga, H., Numerical calculations of energy deposition by broad high-energy electron beams, Phys. Med. Biol., Vol. 37, p2103–2106, 1992.
Shiu, A.S. et al., Verification data for electron beam dose algorithms, Med. Phys., Vol. 19, p623–636, 1992.
McKenzie, A.L., Air-gap correction in electron treatment planning, Phys. Med. Biol., Vol. 24, p628–635, 1979.
Ekstrand, K.E., and Dixon, R.L., Obliquely incident electron beams, Med. Phys., Vol. 9, p276–278, 1982.
Biggs, P.J., The effect of beam angulation on central axis depth dose for 4–29 MeV electrons, Phys. Med. Biol., Vol. 29, p1089–1096, 1984.
Khan, F.M., Deibel, F.C., and Soleimani-Meigooni, A., Obliquity correction for electron beams, Med. Phys., Vol. 12, p749–753, 1985.
Ulin, K., and Sternick, E.S., An isodose shift technique for obliquely incident electron beams, Med. Phys., Vol. 16, p905–910, 1989.
Task Group 21, Radiation Therapy Committee, American Association of Physicists in Medicine, A protocol for the determination of absorbed dose from high-energy photon and electron beams, Med. Phys., Vol. 10, p741–771, 1983.
Biggs, P.J., Boyer, A.L., and Doppke, K.P., Electron dosimetry of irregular fields on the Clinac-18, Int. J. Radiat. Oncol. Biol. Phys., Vol. 5, p433–440, 1979.
Purdy, J.M., Choi, M.C., and Feldman, A., Lipowitz metal shielding thickness for dose reduction of 6-20 MeV electrons, Med. Phys., Vol. 7, p251–253, 1980.
Lightstone, A.W., Videla., N., and Mason, D.L.D., Exceptional increases in electron cone output as the backup diaphragms are opened, Med. Phys., Vol. 24, pp 133–134, 1997.
Mills, M.D., Hogstrom, K.R., and Almond, P.R., Prediction of electron beam output factors, Med. Phys., Vol. 9, p60–68, 1982.
McParland, B.J., A parametrization of the electron beam output factors for a 25 MeV linear accelerator, Med. Phys., Vol. 14, p666–669, 1987.
McParland, B.J., A method of calculating output factors for arbitrarily shaped electron fields, Med. Phys., Vol. 16, p88–93, 1989.
42. McParland, B.J., An analysis of equivalent fields for electron beam central axis dose calculation, Med. Phys., Vol. 19, p901–906, 1992.
43. Choi, M.C., Purdy, J.A., Gerbi, B.J., Abrath, F.G., and Glasgow, G.P., Variation in output factors caused by secondary blocking for 7-16 MeV electron beams, Med. Phys., Vol. 6, p137–139, 1979.
Khan, F.M.,and Higgins, P.D., Calculation of depth dose and dose per monitor unit for irregularly shaped electron fields, Phys. Med. Biol., Vol. 44, pp N77–N80, 1999.
Giarattano, J.C., Duerkes, R.J., and Almond, P.R., Lead shielding thickness for dose reduction of 7–20 MeV electrons, Med. Phys., Vol. 2, p336–337, 1975.
Khan, F.M., Moore, V.C., and Levitt, S.H., Field shaping in electron therapy, Br. J. Radiol., Vol. 49, p883–886, 1976.
Khan, F.M., Werner, B.L., and Deibel, F.C., Lead shielding for electrons, Med. Phys., Vol. 8, p712–713, 1981.
Asbell, S.O., Sill, J., Lightfoot, D.A., and Brady, N.L., Individualized eye shield for use in electron beam therapy as well as low energy photon irradiation, Int. J. Radiat. Oncol. Biol. Phys., Vol. 6, p519–521, 1980.
Saunders, J.E., and Peters, V.G., Backscattering frommetals in superficial therapy with highenergy electrons, Br. J. Radiol., Vol. 47, p467–470, 1974.
Gagnon, W.F., and Cundiff, J.H., Dose enhancement from back-scattered radiation at tissue metal interfaces irradiated with high energy electrons, Br. J. Radiol., Vol. 53, p466–470, 1980.
Klavenhagen, S.C., Lambert, G.D., and Arbari, A., Backscattering in electron therapy for energies between 3 and 35 MeV, Phys. Med. Biol., Vol. 27, p363–373, 1982.
Frank, H., Zur Vielfachstreuung und R, cksdiffusion schneller Elektronen nach Durchgang durch dicke Schichten, Z. Naturforsch., Vol. 14a, p247–261, 1959.
Bjarngard, B.E., McCall, R.C., and Berstein, I.A., Lithium fluoride teflon thermoluminescent dosimeters, p308–316, in Proceedings of First International Conference on Luminescence Dosimetry, Stanford, Attix, F.H. (Ed.), Conference no. 650637, U.S. Atomic Energy Commission, Washington, D.C., 1967.
Dutreix, J., and Bernard, M., Dosimetry at interface for high-energy x and ? rays, Br. J. Radiol., Vol. 39, p205–210, 1966.
Khan, F.M., Sewchand, W., and Levitt, S.H., Effect of air space on depth dose in electron beam therapy, Radiology, Vol. 126, p249–252, 1978.
Jamshedi, A., Kuchnir, F.J., and Reft, C.S., Determination of the source position for the electron beams from a high energy linear accelerator, Med. Phys., Vol. 13, p942–948, 1986.
Laughlin, J.S., High-energy electron treatment planning for inhomogeneities, Br. J. Radiol., Vol 38, p143–147, 1965.
Boone, M.L.M., Jardine, J.H., Wright, A.E., and Tapley, N., High-energy electron dose perturbations in the regions of tissue heterogeneity. I. In vivo dosimetry, Radiology, Vol. 88, p1136–1145, 1967.
Almond, P.R., Wright, A.E., and Boone, M.L.M., High-energy electron dose perturbations in regions of tissue heterogeneity. II. Physical models of tissue heterogeneities, Radiology, Vol. 88, p1146–1153, 1967.
Pohlit, W., Calculated and measured dose distributions in inhomogeneous materials and in patients, Ann. N.Y. Acad. Sci., Vol. 161, p189–197, 1969.
Brenner, M., Karjalainen, P., Rytila, A., and Jungar, H., The effects of inhomogeneities on dose distribution of high-energy electrons, Ann. N.Y. Acad. Sci., Vol. 161, p189–197, 1969.
Shrott, K.R., Ross, C.K., Bielajew, A.F., and Rogers, D.W.O., Electron beam dose distributions near standard inhomogeneities, Phys. Med. Biol., Vol. 31, p235–249, 1986.
Hogstrom, K.R., Dosimetry of electron heterogeneities, p532–561, in Radiation Oncology Physics — 1986, Medical Physics Monograph 15, Keriakes, J.G., Elson, H.R., and Born, C.G. (Eds.), American Institute of Physics, New York, 1987.
Amdur, R.J., Kalbaugh, K.J., Ewald, L.M., Parsons, J.T., Mendenhall, W.M., Bova, F.J., and Million, R.R., Radiation therapy of skin cancer near the eye: Kilovoltage X-rays versus electrons, Int. J. Radiat. Oncol. Biol. Phys., Vol. 23, p769–779, 1992.
Lovett, R.D., Perez, C.A., Shapiro, S.J., and Garcia, D.M., External irradiation of epithelial skin cancers, Int. J. Radiat. Oncol. Biol. Phys., Vol. 19, p235–242, 1990.
Williams, P.C., Hunter, R.D., and Jackson, S.M., Whole body electron therapy in mycosis fungoides — a successful translational technique achieved by modification of an established linear accelerator, Br. J. Radiol., Vol. 52, p302–307, 1979.
AAPM Task Group 30, AAPM Monograph 23, Total Skin Electron Therapy and Dosimetry, American Association of Physicists in Medicine, Radiation Therapy Committee, Report of Task Group 30, American Institute of Physics, New York, 1988.
Almond, P.R., Total skin electron irradiation and dosimetry, p296–332, in Radiation Oncology Physics — 1986, Medical Physics Monograph 15, Keriakes, J.G., Elson, H.R., and Born, C.G., (Eds.), American Institute of Physics, New York, 1987.
Page, V., Garner, A., and Karzmark, C.J., Patient dosimetry in electron treatment of large superficial lesions, Radiology, Vol. 94, p635–641, 1970.
Goldson, A.L., Preliminary clinical experience with intraoperative radiotherapy, J. Natl. Med. Assoc., Vol. 70, p493–495, 1978.
Biggs, P.J., Epp, E.R., Ling, C.L., Novack, D.H., and Michaels, H.B., Dosimetry, field shaping and other considerations for intraoperative electron therapy, Int. J. Radiat. Oncol. Biol. Phys., Vol. 7, p875–884, 1981.
McCullough, E.C., and Anderson, J.A., The dosimetric propertiesofanapplicator system for intraoperative electron-beam therapy utilizing a Clinac-18 accelerator, Med. Phys., Vol. 9, p261–268, 1982.
McCullogh, E.C., and Biggs, P.J., Intraoperative electron therapy, p333–347, in Radiation Oncology Physics — 1986, Medical Physics Monograph 15, Keriakes, J.G., Elson, H.R., and Born, C.G., (Eds.), American Institute of Physics, New York, 1987.
Hogstrom, K.R., Boyer, A.L., Shiu, A.S., Ocharn, G., Kirsher, S.M., Krispel, F., and Rich, T., Design of metallic electron beam cones for an intraoperative therapy linear accelerator, Int. J. Radiat. Oncol. Biol. Phys., Vol. 18, p1227–1332, 1990.
Nelson, C.E., Cook, R., and Rafkel, S., The dosimetric properties of an intraoperative radiation therapy applicator system, Med. Phys., Vol. 16, p794–799, 1989.
Palta, J.R., Biggs, P.J., Hazle, J.D., Huq, M.S., Dahl, R.A., Ochran, T.G., Soen, J., Dobelbower, Jr., R.R., and McCullough, E.C., Intraoperative electron beam therapy: technique, dosimetry, and dose specification: Report of Task Force 48, Radiation Therapy Committee, American Association of Physicists in Medicine, Int. J. Radiat. Oncol. Biol. Phys., Vol. 33, pp725–746, 1995.
Dobblebower, R.R. and Abe, M. (Eds.), Intraoperative Radiation Therapy, CRC Press, Boca Raton, Florida, 1989.
Calvo, F.A., Hoekstra, H.J., and Lehnert, T., Intraoperative radiotherapy: 20 years of clinical experience, technological development and consolidation of results (Review), European J. Surg. Oncol., Vol. 26, Spplement A, pp S1–S4, 2000.
Valentini, V., Balducci, M., Morganti, A.G., De Giorgi, U., and Fiorentini, G., Intraoperative radiotherapy: current thinking, European J. of Surg. Oncol., Vol. 28, pp180–185, 2001
Mills, M.D., Fajardo, L. C., Wilson, D. L., Daves, J. L. and Spanos, W.J., Commissioning of a mobile electron accelerator for intraoperative radiotherapy, J. Appl. Clin. Med. Phys., Vol. 2, pp121–130, 2001.
Meurk, M.L., Goer, D.A., Spalek, G., and Cook, T., The Mobetron: A new concept for IORT, pp 65–70, in Intraoperative Radiotherapy in the Treatment of Cancer, (ED: Vaeth, J.M.), Karger, Basel, 1997.
Leavitt, D.D., Peacock, L.M., Gibbs, F.A., and Stewart, J.R., Electron arc therapy: Physical measurements and treatment planning techniques, Int. J. Radiat. Oncol. Biol. Phys., Vol. 11, p985–999, 1985.
Hogstrom, K.R., and Leavitt, D., Dosimetry of arc electron therapy, p265–295, in Radiation Oncology Physics — 1986, Medical Physics Monograph 15, Keriakes, J.G., Elson, H.R., and Born, C.G., (Eds.), American Institute of Physics, New York, 1987.
Khan, F.M., Calibration and treatment planning of electron beam arc therapy, p249–266, in Electron Dosimetry and Arc Therapy, Proceedings of Symposium, Paliwal, B. (Ed.), American Institute of Physics, New York, 1982.
Levitt, D.D., Stewart, J.R., Moeller, J.H., and Early, L., Optimization of electron arc therapy by multi-vane collimator control, Int. J. Radiat. Oncol. Biol. Phys., Vol. 16, p489–496, 1989.
Lam, K.S., Lam, W.C., O’Neill, M.J., and Zinreich, E., Electron arc therapy: Beam datarequirements and treatment planning, Clin. Radiol., Vol. 38, p379–383, 1987.
Pla, M., Podgorsak, E.B., Pla, C., and Freeman, C.R., Determination of secondary collimator shape in electron arc therapy, Phys. Med. Biol., Vol. 38, p999–1006, 1993.
Pla, M., Pla, C., and Podgorsak, E.B., The influence of beam parameters on percentage depth dose in electron arc therapy, Med. Phys., Vol. 15, p49–55, 1988.
Pla, M., Podgorsak, E.B., Freeman, C.R., Souhami, L., and Guerra, J., Physical aspects of the angle ß concept in electron arc therapy, Int. J. Radiat. Oncol. Biol. Phys., Vol. 20, p1331–1339, 1991.
Olivares-Pla, M., Podgorsak, E.B., and Pla, C., Electron arc dose distributions as a function of beam energy, Med. Phys., Vol. 24, pp127–132, 1997
Boyer, A.L., Fullerton, G.D., and Mira, J.G., An electron beam pseudoarc technique for irradiation of large areas of chest wall and other curved surfaces, Int. J. Radiat. Oncol. Biol. Phys., Vol. 8, p1969–1974, 1982.
McKenzie, M.R., Freeman, C.R., Pla, M., Guerra, J., Souhami, L., Pla, C., and Podgorsak, E.B., Clinical experience with pseudoarc therapy, Br. J. Radiol., Vol. 66, p234–240, 1993.
Boyer, A.L., Fullerton, G.D., Mira, J.G., and Mok, E.C., An electron beam pseudo arc technique, p267–293, in Electron Dosimetry and Arc Therapy, Proceedings of Symposium, Paliwal, B. (Ed.), American Institute of Physics, New York, 1982.
Pla, M., Podgorsak, E.B., and Pla, C., Electron dose rate and photon contamination in electron arc therapy, Med. Phys., Vol. 16, p692–697, 1989.
Bagne, F., Adjacent fields of high-energy X-rays and electrons, Phys. Med. Biol., Vol. 23, p1186–1191, 1978.
Bhaduri, D., Choi, M.C., Weaver, J., and Agarwal, S.K., Matching of electron fields on flat surfaces, J. Am. Assoc. Med. Dosim., Vol. 9, p12–16, 1984.
Frass, B.A., Tepper, J.E., Glatstein, E., and van de Geijn, J.A., Clinical use of a matchline wedge for adjacent megavoltage radiation field line matching, Int. J. Radiat. Oncol. Biol. Phys., Vol. 9, p209–216, 1983.
Kalend, A., Zwicker, R.D., Wu, A., and Sternick, E.S., A beam edge modifier for abutting electron fields, Med. Phys., Vol. 12, p793–798, 1985.
Kurup, R.G., Wang, S., and Glasgow, G.P., Field matching of electron beams using plastic wedge penumbra generators, Phys. Med. Biol., Vol. 37, p145–153, 1992.
Kurup, R.G., Glasgow, G.P., and Leybovich, L.B., Design of electron beam wedges for increasing penumbra abutting fields, Phys. Med. Biol., Vol. 38, p667–674, 1993.
McKenzie, A.L., A simple method for matching electron beams in radiotherapy, Phys. Med. Biol., Vol. 43, pp3465–3478, 1998.
Lachance, B., Tremblay, D., and Pouliot, J., Anew penumbra generator for electronfields matching, Med. Phys., Vol. 24, pp485–495, 1997.
Papiez, E., Dunscombe, P.B., and Malakar, K., Matching photon and electronfieldsinthetreatment of head and neck tumors, Med. Phys., Vol. 19, p335–341, 1992.
Additional Reading
Task Group 25, Radiation Therapy Committee, American Association of Physicists in Medicine, Clinical Electron Beam Dosimetry, Med. Phys., Vol. 18, p73–109, 1991.
ICRU Report 35, Radiation Dosimetry: Electron Beams with Energies Between 1 and 50 MeV, International Commission on Radiological Units and Measurements, Bethesda, Maryland, 1984.
Klavenhagen, S.C., Physics of Electron Beam Therapy, HPA Medical Physics Handbook 13, Adam Hilger, Bristol, 1985.
Keriakes, J.G., Elson, H.R., and Born, C.G. (Eds.), Radiation Oncology Physics — 1986, Medical Physics Monograph 15, American Institute of Physics, New York, 1987.
Vaeth, J.M., and Meyer, J.L. (Eds.), The Role of High Energy Electrons in the Treatment of Cancer, Karger, Basel, 1991.
Jayaraman, S., Pathways and pitfalls in treatment planning with external beams: the role of the clinical physicist, Radiographics, Vol. 8, p.1147–1170, 1988.
Author information
Authors and Affiliations
Rights and permissions
Copyright information
© 2004 Springer-Verlag Berlin Heidelberg
About this chapter
Cite this chapter
Jayaraman, S., Lanzl, L.H. (2004). Physical Aspects of Electron Beam Therapy. In: Clinical Radiotherapy Physics. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-18549-6_16
Download citation
DOI: https://doi.org/10.1007/978-3-642-18549-6_16
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-642-62155-0
Online ISBN: 978-3-642-18549-6
eBook Packages: Springer Book Archive