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Part No...., Module No....Lesson No

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1 Part No...., Module No....Lesson No
Module title DIAGNOSTIC RADIOLOGY Part 1 : X-ray Beam Aim: To become familiar with the basic knowledge in radiation physics and image formation process. Part …: (Add part number and title) Module…: (Add module number and title) Lesson …: (Add session number and title) Learning objectives: Upon completion of this lesson, the students will be able to: . (Add a list of what the students are expected to learn or be able to do upon completion of the session) Activity: (Add the method used for presenting or conducting the lesson – lecture, demonstration, exercise, laboratory exercise, case study, simulation, etc.) Duration: (Add presentation time or duration of the session – hrs) Materials and equipment needed: (List materials and equipment needed to conduct the session, if appropriate) References: (List the references for the session) IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

2 Part No...., Module No....Lesson No
Module title Contents Introduction to the atomic basic structure Quantities and units Bremsstrahlung production Characteristic X-rays Add module code number and lesson title IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

3 Part No...., Module No....Lesson No
Module title Topic 1 : Introduction to the atomic basic structure Part …: (Add part number and title) Module…: (Add module number and title) Lesson …: (Add session number and title) Learning objectives: Upon completion of this lesson, the students will be able to: . (Add a list of what the students are expected to learn or be able to do upon completion of the session) Activity: (Add the method used for presenting or conducting the lesson – lecture, demonstration, exercise, laboratory exercise, case study, simulation, etc.) Duration: (Add presentation time or duration of the session – hrs) Materials and equipment needed: (List materials and equipment needed to conduct the session, if appropriate) References: (List the references for the session) IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

4 Electromagnetic spectrum
keV 1.5 3 eV 0.12 keV 1 10 102 103 104 IR light UV X and  rays 8000 4000 100 10 1 0.1 0.01 0.001 Angström IR : infrared, UV = ultraviolet

5 Part No...., Module No....Lesson No
Module title The atomic structure The nuclear structure protons and neutrons = nucleons Z protons with a positive electric charge ( C) neutrons with no charge (neutral) number of nucleons = mass number A The extranuclear structure Z electrons (light particles with electric charge) equal to proton charge but negative  The atom is normally electrically neutral IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

6 Part No...., Module No....Lesson No Topic 2 : Quantities and units
Module title Topic 2 : Quantities and units Part …: (Add part number and title) Module…: (Add module number and title) Lesson …: (Add session number and title) Learning objectives: Upon completion of this lesson, the students will be able to: . (Add a list of what the students are expected to learn or be able to do upon completion of the session) Activity: (Add the method used for presenting or conducting the lesson – lecture, demonstration, exercise, laboratory exercise, case study, simulation, etc.) Duration: (Add presentation time or duration of the session – hrs) Materials and equipment needed: (List materials and equipment needed to conduct the session, if appropriate) References: (List the references for the session) IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

7 Basic units in physics (SI system)
Part No...., Module No....Lesson No Module title Basic units in physics (SI system) Electric charge : 1 coulomb [C] Power : 1 watt [W] (1 J/s) 1 mAs = C electron-volt [eV] : J Proton electric charge = C mass of proton : g IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

8 Part No...., Module No....Lesson No
Module title Atom characteristics A, Z and associated quantities Hydrogen A = 1 Z = 1 EK= 13.6 eV Carbon A = 12 Z = 6 EK= 283 eV Phosphor A = 31 Z = 15 EK= 2.1 keV Tungsten A = 183 Z = 74 EK= 69.5 keV Uranium A = 238 Z = 92 EK= keV IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

9 Part No...., Module No....Lesson No
Module title Topic 3 : Bremsstrahlung production Part …: (Add part number and title) Module…: (Add module number and title) Lesson …: (Add session number and title) Learning objectives: Upon completion of this lesson, the students will be able to: . (Add a list of what the students are expected to learn or be able to do upon completion of the session) Activity: (Add the method used for presenting or conducting the lesson – lecture, demonstration, exercise, laboratory exercise, case study, simulation, etc.) Duration: (Add presentation time or duration of the session – hrs) Materials and equipment needed: (List materials and equipment needed to conduct the session, if appropriate) References: (List the references for the session) IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

10 Electron-nucleus interaction (I)
Part No...., Module No....Lesson No Module title Electron-nucleus interaction (I) Bremsstrahlung: radiative energy loss (E) by electrons slowing down on passage through a material  is the deceleration of the incident electron by the nuclear Coulomb field  radiation energy (E) (photon) is emitted. IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

11 Electrons strike the nucleus
n(E) E E1 E2 E3 n1 n3 n2 n1E1 n2E2 n3E3 Emax Bremsstrahlung spectrum

12 Electron-nucleus interaction (II)
Part No...., Module No....Lesson No Module title Electron-nucleus interaction (II) With materials of high atomic number the energy loss is higher The energy loss by Bremsstrahlung > 99% of kinetic E loss as heat production it increases with increasing electron energy X-rays are dominantly produced by Bremsstrahlung IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

13 Bremsstrahlung continuous spectrum
Part No...., Module No....Lesson No Module title Bremsstrahlung continuous spectrum Energy (E) of Bremsstrahlung photons may take any value between “zero” and the maximum kinetic energy of incident electrons Number of photons as a function of E is proportional to 1/E Thick target  continuous linear spectrum IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

14 Bremsstrahlung spectra
Part No...., Module No....Lesson No Module title Bremsstrahlung spectra dN/dE dN/dE (spectral density) E0 E0 E E From a “thick” target From a “thin” target E = energy of emitted photons E0= energy of electrons IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

15 X-ray spectrum energy Maximum energy of Bremsstrahlung photons
kinetic energy of incident electrons In X-ray spectrum of radiology installations: Max (energy) = X-ray tube peak voltage Bremsstrahlung E keV after filtration

16 Ionization and associated energy transfers
Part No...., Module No....Lesson No Module title Ionization and associated energy transfers Example: electrons in water ionization energy : 16 eV (for a water molecule) other energy transfers associated to ionization Excitation energy (each requires only a few eV) thermal transfers (at even lower energy) W = 32 eV is the average loss per ionization it is characteristic of the medium independent of incident particle and of its energy IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

17 Part No...., Module No....Lesson No Topic 4 : Characteristic X-rays
Module title Topic 4 : Characteristic X-rays Part …: (Add part number and title) Module…: (Add module number and title) Lesson …: (Add session number and title) Learning objectives: Upon completion of this lesson, the students will be able to: . (Add a list of what the students are expected to learn or be able to do upon completion of the session) Activity: (Add the method used for presenting or conducting the lesson – lecture, demonstration, exercise, laboratory exercise, case study, simulation, etc.) Duration: (Add presentation time or duration of the session – hrs) Materials and equipment needed: (List materials and equipment needed to conduct the session, if appropriate) References: (List the references for the session) IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

18 Spectral distribution of characteristic X-rays (I)
Part No...., Module No....Lesson No Spectral distribution of characteristic X-rays (I) Module title Starts with ejection of e- mainly from k shell (also possible for L, M,…) by ionization e- from L or M shell fall into the vacancy created in the k shell Energy difference is emitted as photons A sequence of successive electron transitions between energy levels Energy of emitted photons is characteristic of the atom IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

19 Spectral distribution of characteristic X-rays (II)
Part No...., Module No....Lesson No Module title Spectral distribution of characteristic X-rays (II) L K M N O P Energy (eV) 6 5 4 3 2 - 20 - 70 - 590 - 2800 100 80 60 40 20 L L L K1 K2 K2 K1 (keV) IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

20 Part No...., Module No....Lesson No
Module title Summary The elemental parts of the atom constituting both the nucleus and the extranucleus structure can contribute to photon production. Electrons and photons have different types of interactions with matter Two different forms of x-rays production, Bremsstrahlung and characteristic radiation contribute to the image formation process. Let’s summarize the main subjects we did cover in this session. (List the main subjects covered and stress again the important features of the session) Add module code number and lesson title IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

21 Where to Get More Information
Part No...., Module No....Lesson No Module title Where to Get More Information Attix FH. Introduction to radiological physics and radiation dosimetry. New York, NY: John Wiley & Sons, pp. ISBN Johns HE, Cunningham JR. Solution to selected problems from the physics of radiology 4th edition. Springfield, IL: Charles C. Thomas, 1991. Wahlstrom B. Understanding Radiation. Madison, WI: Medical Physics Publishing, ISBN Add module code number and lesson title IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

22 DIAGNOSTIC RADIOLOGY Part 2 X-ray production
Part No...., Module No....Lesson No Module title DIAGNOSTIC RADIOLOGY Part 2 X-ray production Aim: To become familiar with the technological principles of the X-ray production. Part …: (Add part number and title) Module…: (Add module number and title) Lesson …: (Add session number and title) Learning objectives: Upon completion of this lesson, the students will be able to: . (Add a list of what the students are expected to learn or be able to do upon completion of the session) Activity: (Add the method used for presenting or conducting the lesson – lecture, demonstration, exercise, laboratory exercise, case study, simulation, etc.) Duration: (Add presentation time or duration of the session – hrs) Materials and equipment needed: (List materials and equipment needed to conduct the session, if appropriate) References: (List the references for the session) IAEA Post Graduate Educational Course Radiation Protection and Safe Use of Radiation Sources IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

23 Part No...., Module No....Lesson No
Module title Introduction A review is made of: The main elements of the of x-rays tube: cathode and anode structure The technology constraints of the anode and cathode material The rating charts and x-ray tube heat loading capacities Explanation or/and additional information Instructions for the lecturer/trainer Add module code number and lesson title IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

24 Part No...., Module No....Lesson No
Module title Contents Basic elements of an X-ray source assembly Cathode structure Anode structure Rating chart Explanation or/and additional information Instructions for the lecturer/trainer Add module code number and lesson title IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

25 Topic 1: Basic elements of the x-ray assembly source
Generator : power circuit supplying the required potential to the X-ray tube X-ray tube and collimator: device producing the X-ray beam

26 Add module code number and lesson title
X-ray tube components Cathode : heated filament which is the source of the electron beam directed towards the anode tungsten filament Anode (stationary or rotating): impacted by electrons, emits X-rays Metal tube housing surrounding glass X-ray tube (electrons are traveling in vacuum) Shielding material (protection against scattered radiation) Add module code number and lesson title

27 Add module code number and lesson title
X-ray tube components 1: long tungsten filament 2 : short tungsten filament 3 : real size cathode 1: mark of focal spot Add module code number and lesson title

28 Topic 2: Cathode structure (I)
Cathode includes filament(s) and associated circuitry tungsten material : preferred because of its high melting point (3370°C) slow filament evaporation no arcing minimum deposit of W on glass envelope To reduce evaporation the emission temperature of the cathode is reached just before the exposure in stand-by, temperature is kept at ± 1500°C so that 2700°C emission temperature can be reached within a second Add module code number and lesson title

29 Add module code number and lesson title
Cathode structure (I) Modern tubes have two filaments a long one : higher current/lower resolution a short one : lower current/higher resolution Coulomb interaction makes the electron beam divergent on the travel to the anode, thus: lack of electrons producing X-rays larger area of target used focal spot increased  lower image resolution Focalization of electrons is crucial Add module code number and lesson title

30 Topic 3 : Anode structure (X-ray tube characteristics)
Anode mechanical constraints Material : tungsten, rhenium, molybdenum, graphite Focal spot : surface of anode impacted by electrons Anode angle Disk and annular track diameter (rotation frequency from 3,000 to 10,000 revolutions/minute) Thickness  mass and material (volume)  heat capacity Anode thermal constraints Instantaneous power load (heat unit) Heat loading time curve Cooling time curve Add module code number and lesson title

31 Anode angle (I) This conflict is solved by slanting the target face
The Line-Focus principle Anode target plate has a shape that is more rectangular or ellipsoidal than circular the shape depends on : filament size and shape focusing cup’s and potential distance between cathode and anode Image resolution requires a small focal spot Heat dissipation requires a large spot This conflict is solved by slanting the target face Add module code number and lesson title

32 THE BETTER THE RESOLUTION
Anode angle (II) Angle Angle Actual focal spot size Actual focal spot size Incident electron beam width Incident electron beam width Increased apparent focal spot size Apparent focal spot size Film Film THE SMALLER THE ANGLE THE BETTER THE RESOLUTION Add module code number and lesson title

33 Add module code number and lesson title
Anode heel effect (I) Anode angle (from 7° to 20°) induces a variation of the X-ray output in the plane comprising the anode-cathode axis Absorption of photons by anode body is more in low emission angle The magnitude of influence of the heel effect on the image depends on factors such as : anode angle size of film (FOV) focus to film distance Anode aging increases heel effect Add module code number and lesson title

34 Add module code number and lesson title
Anode heel effect (II) The heel effect is not always a negative factor It can be used to compensate for different attenuation through parts of the body For example: thoracic spine (thicker part of the patient towards the cathode side of the tube) mammography Add module code number and lesson title

35 Focal spot size and imaging geometry
Focal spot finite size  image unsharpened Improving sharpness  small focal spot size For mammography focal spot size  0.4 Small focal spot size  reduced tube output (longer exposure time) Large focal spot allows high output (shorter exposure time) Balance depends on organ movement (fats moving organs may require larger focus) Add module code number and lesson title

36 Topic 4: X-ray tube rating chart (I)
Tube cooling characteristics and focal spot size  {mA - time} relationship at constant kV intensity decreases with increasing exposure time Note: higher power  reduced exposure time  reduced motion unsharpness Add module code number and lesson title

37 Heat loading capacities
A procedure generates an amount of heat depending on: kV used, tube current (mA), length of exposure type of voltage waveform number of exposures taken in rapid sequence Heat Unit (HU) [joule] : unit of potential x unit of tube current x unit of time The heat generated by various types of X-ray circuits are: 1 phase units : HU = kV x mA x s 3 phase units, 6 pulse : HU = 1.35 kV x mA x s 3 phase units, 12 pulse: HU = 1.41 kV x mA x s J = HU x 0.71 Add module code number and lesson title

38 X-ray tube rating chart (II)
Manufacturers combine heat loading characteristics and information about the limits of their x-ray tubes in graphical representations called Tube Rating Charts Example : Tube A : a 300 mA, 0.5 s, 90 kV procedure would damage the system operated from a 1  half wave rectified generator (unacceptable) Tube B : a 200 mA, 0.1 s, 120 kV procedure comply with the technical characteristics of the system operated from a 3  fully rectified generator (acceptable) Add module code number and lesson title

39 X-ray tube rating chart (IV)
Part No...., Module No....Lesson No Module title X-ray tube rating chart (IV) 700 600 500 400 300 200 100 X-ray tube B 3 full-wave rectified rpm 1.0 mm effective focal spot 70 kVp 50 kVp Tube current (mA) 90 kVp 125 kVp As can be seen a 200 mA, 0.1 s, 120 kV procedure comply with the technical characteristics of the system operated from a 3  fully rectified generator (acceptable) Acceptable 0.01 0.05 0.1 0.5 1.0 5.0 10.0 Exposure time (s) Add module code number and lesson title IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

40 Anode cooling chart (I)
Heat generated is stored in the anode, and dissipated through the cooling circuit A typical cooling chart has : input curves (heat units stored as a function of time) anode cooling curve The following graph shows that : a procedure delivering 500 HU/s can go on indefinitely if it is delivering 1000 HU/s it has to stop after 10 min if the anode has stored HU, it will take  5 min to cool down. Add module code number and lesson title

41 Anode cooling chart (II)
Part No...., Module No....Lesson No Module title Anode cooling chart (II) Maximum Heat Storage Capacity of Anode 240 220 200 180 160 140 120 100 80 60 40 20 Elapsed time (min) Heat units stored (x 1000) 500 HU/sec 1000 HU/sec 350 HU/sec 250 HU/sec Imput curve Cooling curve The graph shows that : a procedure delivering 500 HU/s can go on indefinitely if it is delivering 1000 HU/s it has to stop after 10 min if the anode has stored HU, it will take  5 min to cool down completely Add module code number and lesson title IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

42 Part No...., Module No....Lesson No
Module title Summary The main parts of the system contributing to the desired X-ray production: provide the required source of power deliver an appropriate x-ray spectrum ensure the optimum adjustment of exposure to warrant the image quality Let’s summarize the main subjects we did cover in this session. (List the main subjects covered and stress again the important features of the session) Add module code number and lesson title IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

43 Where to Get More Information
Part No...., Module No....Lesson No Module title Where to Get More Information Equipment for diagnostic radiology, E. Forster, MTP Press, 1993 The Essential Physics of Medical Imaging, Williams and Wilkins. Baltimore:1994 Manufacturers data sets for different x-ray tubes Add module code number and lesson title IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

44 Part No...., Module No....Lesson No
Module title DIAGNOSTIC RADIOLOGY Part 3: X-ray Equipment and Parts Aim: To become familiar with the technological principles of the X-ray production. IAEA Post Graduate Educational Course Radiation Protection and Safe Use of Radiation Sources IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

45 Part No...., Module No....Lesson No
Module title Introduction A review is made of: The system for x-ray beam production : generator, rating chart, automatic exposure control system The mode of operation of X-ray equipment Explanation or/and additional information Instructions for the lecturer/trainer Add module code number and lesson title IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

46 Part No...., Module No....Lesson No
Module title Contents Rating chart X-ray generator Automatic Exposure Control (AEC) X-ray equipment operation and mode Explanation or/and additional information Instructions for the lecturer/trainer Add module code number and lesson title IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

47 Part No...., Module No....Lesson No Topic 1 : X-ray generator
Module title Topic 1 : X-ray generator Part …: (Add part number and title) Module…: (Add module number and title) Lesson …: (Add session number and title) Learning objectives: Upon completion of this lesson, the students will be able to: . (Add a list of what the students are expected to learn or be able to do upon completion of the session) Activity: (Add the method used for presenting or conducting the lesson – lecture, demonstration, exercise, laboratory exercise, case study, simulation, etc.) Duration: (Add presentation time or duration of the session – hrs) Materials and equipment needed: (List materials and equipment needed to conduct the session, if appropriate) References: (List the references for the session) IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

48 Add module code number and lesson title
X-ray generator (I) It supplies the X-ray tube with :  Current to heat the cathode filament  Potential to accelerate electrons  Automatic control of exposure (power application time)  Energy supply  1000  X-ray beam energy (of which 99.9% is dissipated as thermal energy) Add module code number and lesson title

49 Add module code number and lesson title
X-ray generator (II) Generator characteristics have a strong influence on the contrast and sharpness of the radiographic image The motion unsharpness can be greatly reduced by a generator allowing an exposure time as short as achievable Since the dose at the image plane can be expressed as : D = k0 . kVpn . I . T kVp : peak voltage (kV) I : mean current (mA) T : exposure time (ms) n : ranging from about 3 at 150 kV to 5 at 50 kV Add module code number and lesson title

50 Add module code number and lesson title
X-ray generator (III) Peak voltage value has an influence on the beam hardness It has to be related to medical question What is the anatomical structure to investigate ? What is the contrast level needed ? The ripple “r” of a generator has to be as low as possible r = [(kV - kVmin)/kV] x 100% Add module code number and lesson title

51 Tube potential wave form (I)
” Conventional generators single  1-pulse (dental and some mobile systems) single  2-pulse (double rectification) three  6-pulse three  12-pulse Constant potential generators (CP) HF generators (use of DC choppers to convert 50Hz mains into voltages with frequencies in the kHz range)  “Inverter technology Add module code number and lesson title

52 Tube potential wave form (II)
Single phase single pulse kV ripple (%) 100% Single phase 2-pulse 13% Three phase 6-pulse 4% Three phase 12-pulse Line voltage 0.01 s 0.02 s Add module code number and lesson title

53 The choice of Generator (I)
Single pulse : low power (<2 kW) 2-pulse : low and medium power 6-pulse : uses 3-phase mains, medium and high power (manual or automatic compensation for voltage drop) 12-pulse : uses two shifted 3-phase system, high power up to 150 kW HF : combines the advantages of constant potential and conventional generator reproducibility and consistency of tube voltage high frame rate possible Add module code number and lesson title

54 Radiation emitted by the x-ray tube
Primary radiation : before interacting photons Scattered radiation : after at least one interaction Leakage radiation : not absorbed by the x-ray tube housing shielding Transmitted radiation : emerging after passage through matter  Antiscatter grid

55 Factors influencing the x-ray spectrum
X-ray spectrum at 30 kV for an X-ray tube with a Mo target and a 0.03 mm Mo filter tube potential kVp value wave shape of tube potential anode track material W, Mo, Rh etc. X-ray beam filtration inherent + additional 15 10 5 Number of photons (arbitrary normalisation) Energy (keV) Add module code number and lesson title

56 Tube filtration Inherent filtration (always present)
 reduced entrance (skin) dose to the patient (cut off the low energy X-rays which do not contribute to the image) Additional filtration (removable filter) further reduction of patient skin and superficial tissue dose without loss of image quality Total filtration (inherent + added) Total filtration must be > 2.5 mm Al for a > 110 kV generator Measurement of filtration  Half-Value Layer

57 Tube filtration Aluminium filter

58 Scattered radiation Effect on mage quality Effect on patient dose
increasing of blurring loss of contrast Effect on patient dose increasing of superficial and depth dose Possible reduction through :  use of grid  limitation of the field to the useful portion  limitation of the irradiated volume (e.g.:breast compression in mammography)  Higher kVp

59 Add module code number and lesson title
Anti scatter grid (I) The grid (between patient and film) eliminates most of scattered radiation stationary grid moving grid (better performance) focused grid Potter-Bucky system Add module code number and lesson title

60 Add module code number and lesson title
Anti scatter grid (II) Source of X-rays Patient Scattered X-rays Lead Film and cassette Useful X-rays Add module code number and lesson title

61 Part No...., Module No....Lesson No
Module title Topic 2 : Automatic Exposure Control (AEC) Part …: (Add part number and title) Module…: (Add module number and title) Lesson …: (Add session number and title) Learning objectives: Upon completion of this lesson, the students will be able to: . (Add a list of what the students are expected to learn or be able to do upon completion of the session) Activity: (Add the method used for presenting or conducting the lesson – lecture, demonstration, exercise, laboratory exercise, case study, simulation, etc.) Duration: (Add presentation time or duration of the session – hrs) Materials and equipment needed: (List materials and equipment needed to conduct the session, if appropriate) References: (List the references for the session) IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

62 Automatic exposure control
Optimal choice of technical parameters in order to avoid repeated exposures (kV, mA) Radiation detector behind (or in front of) the film cassette (with due correction) Exposure is terminated when the required dose has been integrated Compensation for kVp at a given thickness Compensation for thickness at a given kVp

63 Part No...., Module No....Lesson No
Module title Topic 3 : X-ray equipment operation and mode and Application Part …: (Add part number and title) Module…: (Add module number and title) Lesson …: (Add session number and title) Learning objectives: Upon completion of this lesson, the students will be able to: . (Add a list of what the students are expected to learn or be able to do upon completion of the session) Activity: (Add the method used for presenting or conducting the lesson – lecture, demonstration, exercise, laboratory exercise, case study, simulation, etc.) Duration: (Add presentation time or duration of the session – hrs) Materials and equipment needed: (List materials and equipment needed to conduct the session, if appropriate) References: (List the references for the session) IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

64 X-ray operation mode and application (I)
Mobile Radiography DC Bat or Single phase generator: output : up to few 1.4 focus size with stationary anode Inverter tpye technology: output : up to focus size with rotating anode Mammography Single or 3-phase generator or inverter technology output : Mo or Rh anode focus size output : focus size (magnification) AEC with transparency compensation Add module code number and lesson title

65 X-ray operation mode and application (II)
Radiography and Tomography Single or 3  generators or inverter type technology output : 30 kW at 0.3 focus spot size output : kW at 1.0 focus spot size selection of kV and mAs , AEC Radiography and Fluoroscopy Under couch equipment, 3  or inverter technology - continuous output of W output : 50 kW at 1.0 focus size for spot film output : 30 kW at 0.6 for fluoroscopy (high resolution) priority given to contrast automatic settings of kV Add module code number and lesson title

66 X-Ray operation mode and application (III)
Radiography and Fluoroscopy Over couch equipment, 3  or inverter technology continuous output of at least 500 W output : focus size for spot film output : for fluoroscopy (high resolution) priority given to contrast automatic settings of kV Cardiac angiography 3  generators - continuous output  1kW output : focus size output : focus size frame rate : up to 120 fr/s Add module code number and lesson title

67 Where to Get More Information
Part No...., Module No....Lesson No Module title Where to Get More Information Equipment for diagnostic radiology, E. Forster, MTP Press, 1993 The Essential Physics of Medical Imaging, Williams and Wilkins. Baltimore:1994 Manufacturers data sets for different x-ray tubes Add module code number and lesson title IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources


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