Biomedical Physics II: Treatment Units PDF

12.11.2020 Lecture Biomedical Physics II B.1.2.1 Treatment units Prof. Jan Wilkens TUM | Medicine | Dept. of Radiation Oncology, Klinikum rechts der Isar Biomedical Physics II | B.1.2.1 Treatment units 1 Fig. 1: Depth dose curves relative intensity...

12.11.2020 Lecture Biomedical Physics II B.1.2.1 Treatment units Prof. Jan Wilkens TUM | Medicine | Dept. of Radiation Oncology, Klinikum rechts der Isar Biomedical Physics II | B.1.2.1 Treatment units 1 Fig. 1: Depth dose curves relative intensity Requirement for radiotherapy: high photon energies (MeV) X-ray tubes: up to 500 kV → superficial tumors only Gamma ray units: (Cs-137,) Co-60 depth in water (cm) Source: Schlegel (2002) Biomedical Physics II | B.1.2.1 Treatment units 2 Fig. 2: Cobalt 60 Cobalt 60 half-life: 5.3 a photon energies: 1.17 MeV, 1.33 MeV production: cobalt 59 + neutron (thermal reactor neutrons) Source: Krieger (2005) Biomedical Physics II | B.1.2.1 Treatment units 3 Fig. 3: Gammatron DKFZ Heidelberg Biomedical Physics II | B.1.2.1 Treatment units 4 Fig. 4: Cobalt treatment head Source: Krieger (2005) Biomedical Physics II | B.1.2.1 Treatment units 5 Fig. 5: Gamma-Knife Source: Schlegel (2007) Biomedical Physics II | B.1.2.1 Treatment units 6 Fig. 6: Gamma-Knife www.elekta.com Source: Schlegel (2007) Biomedical Physics II | B.1.2.1 Treatment units 7 Fig. 7: Gamma-Knife www.elekta.com 192 sources Co-60, ~240 TBq Collimator sizes: 4 mm, 8 mm, 16 mm Biomedical Physics II | B.1.2.1 Treatment units 8 Fig. 8: Wideröe linear accelerator Source: Krieger (2005) Biomedical Physics II | B.1.2.1 Treatment units 9 Fig. 9: v/c for electrons Source: Schlegel (2007) Biomedical Physics II | B.1.2.1 Treatment units 10 Fig. 10: Microwave cavities Typ. freqency: 3 GHz λ = 10cm Size of cavity: λ/4 = 2.5 cm Source: Schlegel (2007) Biomedical Physics II | B.1.2.1 Treatment units 11 Fig. 11: Traveling-wave accelerator Size of cavity: λ/4 = 2.5 cm for U=200 kV; Emax=10 MeV: length = 1.25 m Source: Schlegel (2007) Biomedical Physics II | B.1.2.1 Treatment units 12 Fig. 12: Standing-wave accelerator Source: Schlegel (2007) Biomedical Physics II | B.1.2.1 Treatment units 13 Fig. 13: Standing-wave accelerator Source: Schlegel (2007) Biomedical Physics II | B.1.2.1 Treatment units 14 Fig. 14: Standing-wave accelerator Source: Schlegel (2007) Biomedical Physics II | B.1.2.1 Treatment units 15 Fig. 15: Components of medical linacs Source: Podgorsak (2005) Biomedical Physics II | B.1.2.1 Treatment units 16 Fig. 16: Energy spread in 90° magnet Source: Krieger (2005) Biomedical Physics II | B.1.2.1 Treatment units 17 Fig. 17: 270° magnet Source: Krieger (2005) Biomedical Physics II | B.1.2.1 Treatment units 18 Fig. 18: Electron mode Source: Krieger (2005) Biomedical Physics II | B.1.2.1 Treatment units 19 Fig. 19: Photon mode Source: Schlegel (2007) Biomedical Physics II | B.1.2.1 Treatment units 20 Fig. 20: Flattening filter x-rays Flattening filter jaws Intensity Source: Krieger (2005) Biomedical Physics II | B.1.2.1 Treatment units 21 Fig. 21: Monitor chambers Source: Krieger (2005) Biomedical Physics II | B.1.2.1 Treatment units 22 Fig. 22: Multi leaf collimator (MLC) Source: Krieger (2005) Biomedical Physics II | B.1.2.1 Treatment units 23 Fig. 23: Multi leaf collimator (MLC) Source: Schlegel (2007) Biomedical Physics II | B.1.2.1 Treatment units 24 Fig. 24: Radiation protection heavy concrete regular concrete secondary radiation source primary beam door operator station Source: Krieger (2005) Biomedical Physics II | B.1.2.1 Treatment units 25 Literature Krieger H (2007) Grundlagen der Strahlungsphysik und des Strahlenschutzes, 2. Auflage, Teubner: Wiesbaden Schlegel W, Bille J (2002) Medizinische Physik 2, Springer: Berlin Heidelberg Krieger H (1997) Strahlenphysik, Dosimetrie und Strahlenschutz Band 2, 2. Auflage, Teubner: Stuttgart ICRU (1998) Report 60: Fundamental Quantities and Units for Ionizing Radiation, ICRU: Bethesda Schlegel W, Mahr A (2007) 3D Conformal Radiation Therapy. A multimedia introduction to methods and techniques, Springer: Heidelberg Podgorsak EB (2005) Radiation Oncology Physics: A Handbook for Teachers and Students, IAEA: Vienna Krieger H. (2005) Strahlungsquellen für Technik und Medizin, Teubner: Wiesbaden Biomedical Physics II | B.1.2.1 Treatment units 26