
International Medical Physics & Biomedical Engineering Workshop in Ohrid Congress Centre, 25-28 July 2018 Yves Lemoigne IFMP, Ambilly, France & TERA Foundation @ CERN Geneva, Ch From the beginning to now Following alternatively the « X-rays » line (in green) and the particle line (in red) 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch Two parallel lines: X-Rays & particle 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch First « decade » of radiotherapy 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch First « decade » of radiotherapy 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch First « decade » of radiotherapy Henri Becquerel Marie Sklodowska Curie (7/11/1867-4/7/1934) was a French-Polish physicist and chemist. She was the first person honored with two Nobel Prizes – in physics an chemistry. She was the first female professor at the University of Paris, and in 1995 became the first woman to be entombed on her own merits in the Pantheon in Paris. Marie Curie developed methods for separation of radium from radioactives residues in sufficient quantities to allow for its characterization and the careful study of its properties, therapeutic properties in particular. 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch First « decade » of radiotherapy 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch First « decade » of radiotherapy Red line = Particle Green line = X-Rays 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch Second Decade of Radiotherapy 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch A new 20 years period 1911 : Almost by chance, Claudius Regaud discovers the interest of fractionation Why Fractionation works ? We ‘ll see later with the cell’s cycle and Radiation 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch A new 20 years period High Technology ! 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch A new 20 years period Birth of scientific dosimetry for Radiation Why only Sievert is honored ? 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch A new 20 years period 1913: Hot Cathode Tube 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch A new 20 years period Treatment in the Kitchen or Dining Room of the patient ? • A pré-history stage… In the dining room ? 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch A new 20 years period Machine built by Siemens ! Slow Progresses in the skin depth… 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch A new 20 years period ==> This announces the future Megavoltage machines ? 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch After 40 years : Maturity Period ? 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch After 40 years : Maturity Period ? This machine anticipates the next generation of Megavolts devices 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch The Decade 1929 - 1939 Henri Coutard summarizes what is understood and defines: 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch The Decade 1929 - 1939 Note the modesty of the speech .... 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch The Decade 1929 - 1939 Opens the door to future Teletherapy machines…. 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch The Decade 1929 - 1939 • Important fact at the beginning of the decade: A new era can open... But during the next decade, scientists were busy with less peacefull activities… 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch Ernest Lawrence and Cyclotrons • E.Lawrence has built cyclotrons of increasing size: • In 1929 a 11-Inch ( 26 cm) diameter accelerating Protons to 1 MeV • In 1932 a 27-Inch (65 cm) with a magnet of 80 tons • In 1937 a 37-Inch (89 cm) • In 1939 a 60-Inch (144 cm)See picture below. Lawrence thought only of increasing the power of cyclotrons. Otherwise he could have discovered artificial radioactivity by noticing that his cyclotrons continued to radiate after the swith-off. This new radioactivity was discovered in 1935 by Irene Curie and Frédérick Joliot with less costly equipment. E.L. E.L. 27 inch Cyclotron (1932) 60 inch Cyclotron (1939) 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch W W II and Post War period 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch Synchrotrons • A synchrotron is a particular type of cyclic particle accelerator, descended from the cyclotron, in which the accelerating particle beam travels around a fixed closed- loop path. The magnetic field which bends the particle beam into its closed path increases with time during the accelerating process, being synchronized to the increasing kinetic energy of the particles, hence the name. One of the early large synchrotrons, now retired, is the Bevatron, constructed in 1950 at the Lawrence Berkeley Laboratory. The name of this proton accelerator comes from its power, in the range of 6.3 GeV. 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch Robert Rathbun Wilson Robert R. Wilson: Shaping Matter Robert Wilson’s seminal contribution to proton radiation therapy was made manifest in a paper he published In 1946. Titled “Radiological Use of Fast Protons” (Radiology 1946:47:487-91), the article’s established the fundamental tenets and techniques that are being followed today at about all proton therapy facilities around the world. He was a serious sculptor of international renown, whose works are displayed at many universities and institutions, like Fermilab and he championed unceasingly the peaceful use of atomic energy he helped to unleash.. Despite …. 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch Teletherapy and the “cobalt bomb” • In 1951, University of Saskatchewan medical physicist Dr. Harold Johns and his graduate students became the first researchers in the world to successfully treat a cancer patient using cobalt-60 radiation therapy. •This innovative technology—dubbed the “cobalt bomb” by the media - revolutionized cancer treatment and saved the lives of millions of cancer patients around the world. With this new teletherapy technique: •This radiation machine bombarded cancers deep • The cure rate for cervical cancer soon climbed from in the body where previous therapies had been 25 per cent to 75 per cent. ineffective. In effect, it dropped a «bomb» on • In the '40s, only one in five patients survived for five cancer. years after getting such cancer (Cf Coutard Paper) • It is cheaper than the other techniques • The cobalt bomb is the grandfather of all radiation (Linacs, Proton and Ion therapy…) therapy units in modern cancer facilities today. 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch The Betatron 6 MeV Betatron 1942 • A Betatron is a type of cyclic particle accelerator. • It is essentially a transformer with a torus-shaped vacuum tube as its secondary coil. An alternating current in the primary coils accelerates electrons in the vacuum around a circular path. • The betatron was the first machine capable of producing electron beams at energies higher than could be achieved with a simple electron gun •The maximum energy that a betatron can impart is limited by the strength of the magnetic field due to the saturation of iron and by practical size of the magnet core. The next generation of accelerators, the Synchrotrons overcame these limitations. 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch In the Fifties: Louis Harold Gray & Theo Puck Louis H Gray (1905-1965) an English physicist who worked on the effects of Radiation on Biological systems. He was an early contributor to the field of Radiobiology. • Amongst many other achievements, he defined a unit of radiation dosage which was later named after him as an SI unit, the gray. • The concept of RBE (Relative Biological Effectiveness) of doses of neutrons (1940) • Research into cells in hypoxic tumors and hyperbaric oxygen Theodore Puck (1916 –2005) was an American geneticist born in Chicago, Illinois. • Puck was an early pioneer of "somatic cell genetics" and single-cell plating ( i.e. "cloning".) This work allowed the genetics of human and other mammalian cells to be studied in detail. • Puck's key work ultimately made modern genetics, such as the human genome and other mammalian genome projects, possible. • Puck made many basic discoveries in several areas. His team found that humans had 46 chromosomes rather than 48 which had earlier been believed. 26/07/2018 Yves Lemoigne, PhD, IFMP Ambilly Fr & TERA @ CERN, Geneva, Ch And the linacs come on the scene… Gordon Isaac and the Linac Gordon's right eye was removed on January 11, 1956 because cancer had spread there. His left eye, however, had only a localized tumor that prompted Henry Kaplan to treat it with the electron beam. Cancer Linac-based radiation therapy began in treatment of the first patient in London at Hammersmith Hospital, with an 8 MV machine • Medical grade linacs accelerate electrons using a tuned-cavity waveguide • Some linacs have short, vertically mounted waveguides, while higher energy machines have a horizontal, longer waveguide and a bending magnet to turn the beam verticallytowards the patient. • Medical linacs use monoenergetic electron beams between 4 and 25 MeV, giving an X-ray output with a spectrum of energiesup to and including the electron energy when the electrons are directed at a high-density (such as tungsten) target.
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