Diagnostic Radiology Physics – Lecture 1 Notes
Introduction to Diagnostic Radiology Physics
Course code: ZMT 234/4 – Physics of Diagnostic Radiology
Lecturer: Dr. Nurul Hashikin Ab. Aziz
Institution: School of Physics, Universiti Sains Malaysia
Contact: hashikin@usm.my
Session focus: “Introduction to Diagnostic Radiology Physics”
Definition & Scope of Diagnostic Radiology
Diagnostic radiology = field of medicine utilising X-rays to:
Detect & diagnose diseases / injuries.
Manage patient care.
Guide various medical treatments.
Reference definition: International Atomic Energy Agency (IAEA) link – https://www.iaea.org/resources/rpop/health-professionals/radiology
(underscores clinical & safety dimensions).
Historical Perspective
Wilhelm Conrad Röntgen (inventor of X-rays, 1895).
Left slide imagery: portrait of Röntgen.
Right slide imagery: first radiograph – his wife’s hand “Hand mit Ringen” (hand with rings).
Demonstrated medical potential immediately after discovery.
Electromagnetic (EM) Spectrum – Position of X-rays
Wavelength (λ) span presented (approximate):
100\,\text{m} \;\to\; 0.0001\,\text{nm}Regions & everyday examples:
Radio waves – FM/TV, Radar (\sim100\,\text{m} to 1\,\text{m}).
Microwaves / IR – TV remote, light bulb.
Visible spectrum – sunlight (labelled “Building size” ↔ “Atom size” scale overlay).
Ultraviolet.
X-rays – X-ray machine.
Gamma rays – highest photon energy.
Notable reminder slide: “Where are α and β radiations?”
Alpha & beta are particulate, thus not located on EM spectrum.
Radiation Classification
Two broad categories:
Particulate Radiation
α (\alpha^{++}), β⁺, β⁻, electrons (e^-), protons (p^+), neutrons (n).
Directly ionizing (charged particles deposit energy continuously).
Electromagnetic Radiation
Radio, microwave, IR, visible, UV, X-rays, γ-rays.
Indirectly ionizing photons; energy imparted via liberated secondary electrons.
Ionizing vs Non-ionizing EM:
Non-ionizing: radio → lower-energy UV.
Ionizing: higher-energy UV, X-rays, γ-rays.
Ion-pair concept visualised:
Photon (h\nu) interacts → ejects electron → ion pair formation.
Electron = directly ionizing; photon = indirectly ionizing.
Roles of a Medical Physicist in Diagnostic Radiology (prompt posed)
Although explicit bullet list not given, implied duties include:
Equipment specification, acceptance & commissioning.
Quality control & assurance.
Patient & staff radiation safety.
Optimisation of image quality vs dose.
Teaching & research on emerging technologies.
Course Administrative Information
Course Outline (13 Topics)
X-ray tube & generator.
X-ray spectrum.
X-ray interaction in human body.
Scattered radiation.
Film-screen radiography.
Fluoroscopy.
Tomography.
Mammography.
Digital radiography.
Quality control & testing of radiographic X-ray machine.
Radiographic quality (contrast, resolution, MTF).
Radiation hazards associated with diagnostic radiology.
Current developments in diagnostic radiology.
Course Structure & Weightage
Coursework 50 %
Tests: 2 \times 7.5\% = 15\%
Assignments (4): 25\%
Quizzes: 10\%
Final Examination: 50\%
————————
Total: 100\%“END of class briefing…” indicates administrative discussion concluded.
Fundamentals of X-ray Production
Requires high-speed electrons suddenly decelerated in a target (X-ray tube).
Two dominant emission processes: Characteristic & Bremsstrahlung.
Characteristic X-rays
Occur when incident electron energy Ee is greater than binding energy of an inner-shell electron Eb.
Ee > Eb \;\Rightarrow\; \text{eject inner electron}Electron vacancy filled by outer-shell electron → discrete photon emitted:
E{X\text{-ray}} = E{\text{outer}} - E_{\text{inner}}Energy depends on “gap” between shells; example range:
E_{K\beta} \approx 10{,}000\,\text{eV} - 100\,\text{eV} (material specific).Spectrum lines labelled: Kα, Kβ, …
Idealised intensity chart showed sharp spikes at those energies.
Bremsstrahlung (Braking) X-rays
Produced when incident electron is decelerated in the Coulomb field of nucleus.
Photon energy distribution is continuous from 0 to the maximum electron kinetic energy.
Probability ↑ with higher atomic number Z (denser nuclear charge enhances deceleration).
Slide examples: 40\,\text{keV}, 60\,\text{keV}, 100\,\text{keV} electron energies.
Photon energy magnitude depends on:
Deflection angle of electron.
Incident electron energy.
Distance of closest approach to nucleus.
Composite X-ray Spectrum (Tube Output)
Superposition of:
Continuous Bremsstrahlung curve (broad).
Discrete characteristic spikes (narrow).
Graph axis: relative intensity vs photon energy (0 → 150\,\text{keV}).
Endpoint energy equals accelerating voltage (kVp).
Peak positions of characteristic lines remain fixed for a given target material.
Ethical, Practical & Real-World Implications (highlighted implicitly)
Use of ionizing radiation mandates adherence to radiation protection principles:
Justification, Optimisation (ALARA), Dose Limitation.
Historical example (Röntgen) shows rapid clinical adoption—but emphasises need for ongoing safety oversight (medical physicist role).
Course topics on radiation hazards & quality control reinforce safety culture.
Teasers for Future Lectures
Slides hinted at advanced imaging (fluoroscopy, tomography, mammography, digital).
Mentions of Soteria.AI, OMEGA, Cytom 16, Nosot could refer to AI or vendor systems—suggesting upcoming discussions on current developments & machine learning in radiology.
Introduction to Diagnostic Radiology Physics - Course code: ZMT 234/4 – Physics of Diagnostic Radiology - Lecturer: Dr. Nurul Hashikin Ab. Aziz - Institution: School of Physics, Universiti Sains Malaysia - Contact: hashikin@usm.my - Session focus: “Introduction to Diagnostic Radiology Physics” ## Definition & Scope of Diagnostic Radiology - Diagnostic radiology = field of medicine utilising X-rays to: - Detect & diagnose diseases / injuries. - Manage patient care. - Guide various medical treatments. - Reference definition: International Atomic Energy Agency (IAEA) link – https://www.iaea.org/resources/rpop/health-professionals/radiology
(underscores clinical & safety dimensions). ## Historical Perspective - Wilhelm Conrad Röntgen (inventor of X-rays, 1895). - Left slide imagery: portrait of Röntgen. - Right slide imagery: first radiograph – his wife’s hand “Hand mit Ringen” (hand with rings). - Demonstrated medical potential immediately after discovery. ## Electromagnetic (EM) Spectrum – Position of X-rays - Wavelength (λ) span presented (approximate):
100\,\text{m} \;\to\; 0.0001\,\text{nm} - Regions & everyday examples: - Radio waves – FM/TV, Radar (\sim100\,\text{m} to 1\,\text{m}). - Microwaves / IR – TV remote, light bulb. - Visible spectrum – sunlight (labelled “Building size” ↔ “Atom size” scale overlay). - Ultraviolet. - X-rays – X-ray machine. - Gamma rays – highest photon energy. - Notable reminder slide: “Where are α and β radiations?” - Alpha & beta are particulate, thus not located on EM spectrum. ## Radiation Classification - Two broad categories:1. Particulate Radiation - α (\alpha^{++}), β⁺, β⁻, electrons (e^-), protons (p^+), neutrons (n). - Directly ionizing (charged particles deposit energy continuously). 1. Electromagnetic Radiation - Radio, microwave, IR, visible, UV, X-rays, γ-rays. - Indirectly ionizing photons; energy imparted via liberated secondary electrons. - Ionizing vs Non-ionizing EM: - Non-ionizing: radio → lower-energy UV. - Ionizing: higher-energy UV, X-rays, γ-rays. - Ion-pair concept visualised: - Photon (h\nu) interacts → ejects electron → ion pair formation. - Electron = directly ionizing; photon = indirectly ionizing. ## Roles of a Medical Physicist in Diagnostic Radiology (prompt posed) - Although explicit bullet list not given, implied duties include: - Equipment specification, acceptance & commissioning. - Quality control & assurance. - Patient & staff radiation safety. - Optimisation of image quality vs dose. - Teaching & research on emerging technologies. ## Course Administrative Information ### Course Outline (13 Topics) 1. X-ray tube & generator. 2. X-ray spectrum. 3. X-ray interaction in human body. 4. Scattered radiation. 5. Film-screen radiography. 6. Fluoroscopy. 7. Tomography. 8. Mammography. 9. Digital radiography. 10. Quality control & testing of radiographic X-ray machine. 11. Radiographic quality (contrast, resolution, MTF). 12. Radiation hazards associated with diagnostic radiology. 13. Current developments in diagnostic radiology. ### Course Structure & Weightage - Coursework 50 % - Tests: 2 \times 7.5\% = 15\% - Assignments (4): 25\% - Quizzes: 10\% - Final Examination: 50\%
————————
Total: 100\% - “END of class briefing…” indicates administrative discussion concluded. ## Fundamentals of X-ray Production - Requires high-speed electrons suddenly decelerated in a target (X-ray tube). - Two dominant emission processes: Characteristic & Bremsstrahlung. ### Characteristic X-rays - Occur when incident electron energy Ee is greater than binding energy of an inner-shell electron Eb.
Ee > Eb \;\Rightarrow\; \text{eject inner electron} - Electron vacancy filled by outer-shell electron → discrete photon emitted:
E{\text{X-ray}} = E{\text{outer}} - E_{\text{inner}} - Energy depends on “gap” between shells; example range:
E_{K\beta} \approx 10{,}000\,\text{eV} - 100\,\text{eV} (material specific). - Spectrum lines labelled: Kα, Kβ, … - Idealised intensity chart showed sharp spikes at those energies. ### Bremsstrahlung (Braking) X-rays - Produced when incident electron is decelerated in the Coulomb field of nucleus. - Photon energy distribution is continuous from 0 to the maximum electron kinetic energy. - Probability ↑ with higher atomic number Z (denser nuclear charge enhances deceleration). - Slide examples: 40\,\text{keV}, 60\,\text{keV}, 100\,\text{keV} electron energies. - Photon energy magnitude depends on: - Deflection angle of electron. - Incident electron energy. - Distance of closest approach to nucleus. ## Composite X-ray Spectrum (Tube Output) - Superposition of: - Continuous Bremsstrahlung curve (broad). - Discrete characteristic spikes (narrow). - Graph axis: relative intensity vs photon energy (0 → 150\,\text{keV}). - Endpoint energy equals accelerating voltage (kVp). - Peak positions of characteristic lines remain fixed for a given target material. ## Ethical, Practical & Real-World Implications (highlighted implicitly) - Use of ionizing radiation mandates adherence to radiation protection principles: - Justification, Optimisation (ALARA), Dose Limitation. - Historical example (Röntgen) shows rapid clinical adoption—but emphasises need for ongoing safety oversight (medical physicist role). - Course topics on radiation hazards & quality control reinforce safety culture. ## Teasers for Future Lectures - Slides hinted at advanced imaging (fluoroscopy, tomography, mammography, digital). - Mentions of Soteria.AI, OMEGA, Cytom 16, Nosot could refer to AI or vendor systems—suggesting upcoming discussions on current developments & machine learning in radiology.
Introduction to Diagnostic Radiology Physics - Course code: ZMT 234/4 – Physics of Diagnostic Radiology - Lecturer: Dr. Nurul Hashikin Ab. Aziz - Institution: School of Physics, Universiti Sains Malaysia - Contact: hashikin@usm.my - Session focus: “Introduction to Diagnostic Radiology Physics” ## Definition & Scope of Diagnostic Radiology - Diagnostic radiology = field of medicine utilising X-rays to: - Detect & diagnose diseases / injuries. - Manage patient care. - Guide various medical treatments. - Reference definition: International Atomic Energy Agency (IAEA) link – https://www.iaea.org/resources/rpop/health-professionals/radiology
(underscores clinical & safety dimensions). ## Historical Perspective - Wilhelm Conrad Röntgen (inventor of X-rays, 1895). - Left slide imagery: portrait of Röntgen. - Right slide imagery: first radiograph – his wife’s hand “Hand mit Ringen” (hand with rings). - Demonstrated medical potential immediately after discovery. ## Electromagnetic (EM) Spectrum – Position of X-rays - Wavelength (λ) span presented (approximate):
100\,\text{m} \;\to\; 0.0001\,\text{nm} - Regions & everyday examples: - Radio waves – FM/TV, Radar (\sim100\,\text{m} to 1\,\text{m}). - Microwaves / IR – TV remote, light bulb. - Visible spectrum – sunlight (labelled “Building size” ↔ “Atom size” scale overlay). - Ultraviolet. - X-rays – X-ray machine. - Gamma rays – highest photon energy. - Notable reminder slide: “Where are α and β radiations?” - Alpha & beta are particulate, thus not located on EM spectrum. ## Radiation Classification - Two broad categories:1. Particulate Radiation - α (\alpha^{++}), β⁺, β⁻, electrons (e^-), protons (p^+), neutrons (n). - Directly ionizing (charged particles deposit energy continuously). 1. Electromagnetic Radiation - Radio, microwave, IR, visible, UV, X-rays, γ-rays. - Indirectly ionizing photons; energy imparted via liberated secondary electrons. - Ionizing vs Non-ionizing EM: - Non-ionizing: radio → lower-energy UV. - Ionizing: higher-energy UV, X-rays, γ-rays. - Ion-pair concept visualised: - Photon (h\nu) interacts → ejects electron → ion pair formation. - Electron = directly ionizing; photon = indirectly ionizing. ## Roles of a Medical Physicist in Diagnostic Radiology (prompt posed) - Although explicit bullet list not given, implied duties include: - Equipment specification, acceptance & commissioning. - Quality control & assurance. - Patient & staff radiation safety. - Optimisation of image quality vs dose. - Teaching & research on emerging technologies. ## Course Administrative Information ### Course Outline (13 Topics) 1. X-ray tube & generator. 2. X-ray spectrum. 3. X-ray interaction in human body. 4. Scattered radiation. 5. Film-screen radiography. 6. Fluoroscopy. 7. Tomography. 8. Mammography. 9. Digital radiography. 10. Quality control & testing of radiographic X-ray machine. 11. Radiographic quality (contrast, resolution, MTF). 12. Radiation hazards associated with diagnostic radiology. 13. Current developments in diagnostic radiology. ### Course Structure & Weightage - Coursework 50 % - Tests: 2 \times 7.5\% = 15\% - Assignments (4): 25\% - Quizzes: 10\% - Final Examination: 50\%
————————
Total: 100\% - “END of class briefing…” indicates administrative discussion concluded. ## Fundamentals of X-ray Production - Requires high-speed electrons suddenly decelerated in a target (X-ray tube). - Two dominant emission processes: Characteristic & Bremsstrahlung. ### Characteristic X-rays - Occur when incident electron energy Ee is greater than binding energy of an inner-shell electron Eb.
Ee > Eb \;\Rightarrow\; \text{eject inner electron} - Electron vacancy filled by outer-shell electron → discrete photon emitted:
E{\text{X-ray}} = E{\text{outer}} - E_{\text{inner}} - Energy depends on “gap” between shells; example range:
E_{K\beta} \approx 10{,}000\,\text{eV} - 100\,\text{eV} (material specific). - Spectrum lines labelled: Kα, Kβ, … - Idealised intensity chart showed sharp spikes at those energies. ### Bremsstrahlung (Braking) X-rays - Produced when incident electron is decelerated in the Coulomb field of nucleus. - Photon energy distribution is continuous from 0 to the maximum electron kinetic energy. - Probability ↑ with higher atomic number Z (denser nuclear charge enhances deceleration). - Slide examples: 40\,\text{keV}, 60\,\text{keV}, 100\,\text{keV} electron energies. - Photon energy magnitude depends on: - Deflection angle of electron. - Incident electron energy. - Distance of closest approach to nucleus. ## Composite X-ray Spectrum (Tube Output) - Superposition of: - Continuous Bremsstrahlung curve (broad). - Discrete characteristic spikes (narrow). - Graph axis: relative intensity vs photon energy (0 → 150\,\text{keV}). - Endpoint energy equals accelerating voltage (kVp). - Peak positions of characteristic lines remain fixed for a given target material. ## Ethical, Practical & Real-World Implications (highlighted implicitly) - Use of ionizing radiation mandates adherence to radiation protection principles: - Justification, Optimisation (ALARA), Dose Limitation. - Historical example (Röntgen) shows rapid clinical adoption—but emphasises need for ongoing safety oversight (medical physicist role). - Course topics on radiation hazards & quality control reinforce safety culture. ## Teasers for Future Lectures - Slides hinted at advanced imaging (fluoroscopy, tomography, mammography, digital). - Mentions of Soteria.AI, OMEGA, Cytom 16, Nosot could refer to AI or vendor systems—suggesting upcoming discussions on current developments & machine learning in radiology.