History of Radiological Sci-ence

March 04, 2014

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 MeVe-

hν6 MV

Types of Radiation

Radiation

Ionizing

Non-ionizing

Directly ionizing (charged particle)direct Coulomb interaction with orbital e- of atoms

Indirectly ionizing (neutral particle)1st: release charged particle (photon > e-, e+, neutron > proton or heavier ions)2nd: direct Coulomb interaction between released charged particle and orbital e- of atoms

heat, radio- or microwaves, or visible, infrared, or ultraviolet light

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

What is Radioactivity?

• Radiation emissions as the result of the sponta-neous transmutation of one element to another (element or state)

Discovery of Radiation

On the evening of November 8, 1895

Discovery of Radioactivity

February 26, 1896

X-ray quickly in clinical use

• A woman (50 yrs) with re-current breast cancer

• 18 daily 1-hour irradiation

Imaging: 1896 – Mihajlo I. Pupin in New York City

Therapy: 1896- Emil H. Grubbé in Chicago

History of Radiation in Medicine

Radiotherapy Timeline

1895 1965

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

A Bit History

Roentgen (1901): Discovery of X-raysBecquerel & 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

Milestones in Modern Physics & Radiological Sciences

1895 X-ray Wilhelm Konard Röntgen1896 Natural radioactivity Antoine-Henri Becquerel1897 Electron Joseph John Thomson1898 Radium-226 Pierre & Marie Curie1903 Bragg peak William Henry Bragg1905 Photoelectric effect Albert Einstein1906 Characteristic x-ray Charles G. Barkla1911 Electron charge Robert Millikan1913 Model of hydrogen Neils Bohr1916 W-filament of x-ray tube William D. Coolidge1919 Proton Ernest Rutherford1922 X-ray scattering Arthur H. Compton1926 Quantum mechanics Erwin Schrodinger

1931 Cyclotron Ernest O. Lawrence1932 Neutron James Chadwick1932 Positron Carl D. Anderson1934 Artificial radioactivity Irène Joliot-Curie, Frédéric Joliot1940 Betatron Donald W. Kerst1942 Controlled nuclear fission Enrico Fermi1946 Nuclear magnetic resonance Felix Bloch, Edward Purcell1951 Cobalt-60 machine Harold E. Johns1968 Gamma Knife Lars Leksell1971 Computer Tomography Godfrey Hounsfield, Alan Cormack1973 Magnetic resonance imaging Paul C. Lauterbur, Peter Mansfield

Radiological Sciences

• is a perfect and long-standing example of trans-lational research where basic experimental & theoretical discoveries are rapidly implemented into benefiting humanity through improving pro-cedures in diagnosis and treatment of disease

• Medical Radiation Physics is an outstanding branch of it

SNUH

MGH

SNUH

대한의원 총독부의원1908 년 대한의원 완공1911 년 X- 선 장치 설치 : 정형외과 륀트겐실

▶ 우측에서 본 병원 전경지 ▶ 본 관 ( 시계탑 )

Courtesy of Prof. Chung, J. K.

경성제국대학 의학부

1940 년 방사선의학 강좌

Courtesy of Prof. Chung, J. K.

Now, Radiation Medicine @ SNUHRadiation Oncology, Radiology, Nuclear Medicine

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