2. History of Radiological Science March 04, 2014

3. What is Radiation? Propagation of energy through matter or space in the form of –Particles (e -, β ±, proton, α, neutron, etc.) or –Photons (X-ray, γ-ray, synchrotron light, etc.) 6 MeV ee hνhν 6 MV

4. Types of Radiation Radiation Ionizing Non-ionizing Directly ionizing (charged particle) direct Coulomb interaction with orbital e - of atoms Indirectly ionizing (neutral particle) 1 st : release charged particle (photon > e -, e +, neutron > proton or heavier ions) 2 nd : direct Coulomb interaction between released charged particle and orbital e - of atoms heat, radio- or microwaves, or visible, infrared, or ultraviolet light

5. Energy Absorbed into Body Body temperature rise from 36.4 C° to 36.5 C° 0.1 C° × 4.184 J/ C°/g = 418.4 J/kg ≠ 418.4 Gy Sauna CT Scan One chest CT scan 30 mGy = 30 × 10 -3 J/kg = 0.03 J/kg = 0.03 Gy

6. What is Radioactivity? Radiation emissions as the result of the spontaneous transmutation of one element to another (element or state)

7. Discovery of Radiation On the evening of November 8, 1895

8. Discovery of Radioactivity February 26, 1896

9. X-ray quickly in clinical use A woman (50 yrs) with rec urrent breast cancer 18 daily 1-hour irradiation Imaging: 1896 – Mihajlo I. Pu pin in New York City Therapy: 1896- Emil H. Grubb é in Chicago

10. History of Radiation in Medicine

11. Radiotherapy Timeline 18951965 1980 1950 2000 100-400 keV X-rays Rotational Therapy Radium Brachytherapy Co-60 Teletherapy Low Energy LINAC Betatron Computer Tomography High Energy LINAC Ir-192, Cs-137 Brachytherapy Popular CT, MRI Scanners 3D RT Planning Accurate Dosimetry Computer remote afterloader PET-CT, MR-PET, Dual energy CT IMRT with MLC, Inverse Plans Image-Guided Radiotherapy Targeted therapy Proton and C-ion therapy

12. A Bit History Roentgen (1901): Discovery of X-rays Becquerel & Curie’s (1903): Discovery of radioactivity William Bragg (1915): Discovery of Bragg Peak Willem Einthoven (1924): Invention of Electrocardiogram E. O. Lawrence (1939): Invention of cyclotron Hounsfield & Cormack (1979): Invention of CT Lauterbur & Mansfield (2003): Invention of MRI

13. Milestones in Modern Physics & Radiological Sciences 1895 X-ray Wilhelm Konard Röntgen 1896 Natural radioactivity Antoine-Henri Becquerel 1897 Electron Joseph John Thomson 1898 Radium-226 Pierre & Marie Curie 1903 Bragg peak William Henry Bragg 1905 Photoelectric effect Albert Einstein 1906 Characteristic x-ray Charles G. Barkla 1911 Electron charge Robert Millikan 1913 Model of hydrogen Neils Bohr 1916 W-filament of x-ray tube William D. Coolidge 1919 Proton Ernest Rutherford 1922 X-ray scattering Arthur H. Compton 1926 Quantum mechanics Erwin Schrodinger 1931 Cyclotron Ernest O. Lawrence 1932 Neutron James Chadwick 1932 Positron Carl D. Anderson 1934 Artificial radioactivity Irène Joliot- Curie, Frédéric Joliot 1940 Betatron Donald W. Kerst 1942 Controlled nuclear fission Enrico Fermi 1946 Nuclear magnetic resonance Felix Bloch, Edward Purcell 1951 Cobalt-60 machine Harold E. Johns 1968 Gamma Knife Lars Leksell 1971 Computer Tomography Godfrey Hounsfield, Alan Cormack 1973 Magnetic resonance imaging Paul C. Lauterbur, Peter Mansfield

14. Radiological Sciences is a perfect and long-standing example of translational research where basic experimental & theoretical discoveries are rapidly implemented into benefiting humanity through improving procedures in diagnosis and treatment of disease Medical Radiation Physics is an outstanding branch of it

15. SNUH

16. MGH

17. SNUH

18. 대한의원  총독부의원 1908 년 대한의원 완공 1911 년 X- 선 장치 설치 : 정형외과 륀트겐실 ▶ 우측에서 본 병원 전경지 ▶본 관 ( 시계탑 ) Courtesy of Prof. Chung, J. K.

19. 경성제국대학 의학부 1940 년 방사선의학 강좌 Courtesy of Prof. Chung, J. K.

20. Now, Radiation Medicine @ SNUH Radiation Oncology, Radiology, Nuclear Medicine

21. I ask your guys to open your mind to more broad world and then to work on innovative things