X-Ray Production and Interaction Concepts

Cathode = Source of electrons in the X-ray tube Anode = Target where electrons strike Glass envelope = Evacuated space in which electrons are accelerated Tube current = Controls number of electrons produced (mAs)

Wavelength (λ) = Short wavelength indicates high energy Frequency (υ) = Number of oscillations per unit time Planck's constant (h) = A constant used in energy equations Speed of light (c) = Standard speed of electromagnetic waves in vacuum

Tungsten = High atomic number and melting point Copper = Good conductor but low melting point Lead = Used for radiation shielding Gold = High atomic number, not typically used for anode

<p>Attenuation = Reduction of X-ray intensity as it passes through matter Absorption = Conversion of X-ray photons into different forms of energy Scatter = Deflection of X-ray photons after interacting with matter Transmission = Passing of X-ray photons through matter without interaction</p> Signup and view all the answers

<p>Energy = Joules Potential difference (kV) = Kilovolts Current (mA) = Milliamperes Time (s) = Seconds</p> Signup and view all the answers

<p>Increasing tube current = Increases number of electrons and X-rays Increasing kV = Increases speed and energy of electrons High atomic number of anode = Enhances intensity of X-ray beam Heat generation = Majority of accelerated electron energy is lost as heat</p> Signup and view all the answers

<p>Resolution = Ability to distinguish fine details in an image Contrast = Difference in radiographic density between structures Exposure time = Duration the X-ray machine is active Image quality = Overall clarity and detail of the radiographic image</p> Signup and view all the answers

<p>Electromagnetic radiation = X-rays and gamma rays Ionizing radiation = Radiation capable of removing tightly bound electrons Non-ionizing radiation = Includes radio waves and visible light X-ray imaging = A medical diagnostic method using X-rays</p> Signup and view all the answers

<p>kVp = Maximum energy for X-ray studies HVT = Thickness reducing radiation intensity by half P.E = Photoelectric effect in X-ray interaction μ = Linear attenuation coefficient</p> Signup and view all the answers

<p>Mammography = 25 to 50 kVp Chest X-ray = ≈ 350 kVp General X-ray = 100 to 200 kVp Dental X-ray = 60 to 80 kVp</p> Signup and view all the answers

<p>1 keV = 1.6 x 10^-9 erg 100 kV = 100 kW at 1 A 5 keV = Energy level for soft tissue imaging</p> Signup and view all the answers

<p>I = Unattenuated beam intensity Io = Initial beam intensity e = Mathematical constant for exponential decay x = Thickness of the attenuator</p> Signup and view all the answers

<p>Energy of X-rays = Determines interaction probability Atomic number (Z) = Higher Z increases attenuation Density (ρ) = Density’s role in material absorption Material type = Different materials have different μ values</p> Signup and view all the answers

<p>Photoelectric effect = Complete energy transfer to an electron Compton scattering = Partial energy transfer and deflection Rayleigh scattering = Elastic scattering with no energy loss Pair production = Creation of particle-antiparticle pair</p> Signup and view all the answers

<p>I = I˳ e –μx = Describes intensity decrease due to attenuation (HVT) X1/2 = 0.693 / μ = Calculates half value thickness P = I * V = Power calculation in X-ray generation E = hf = Describes energy of photons</p> Signup and view all the answers

<p>Anode = Site where X-rays are produced Cathode = Electron source in an X-ray tube Collimator = Limits the X-ray beam size Filtration = Removes low-energy X-rays from the beam</p> Signup and view all the answers

<p>Bremsstrahlung X-ray = Produced by the deceleration of electrons near an atomic nucleus Characteristic X-ray = Emitted when an outer shell electron fills a vacancy in the K-shell Diagnostic X-ray = Typically has energies between 15 to 150 keV Visible light photon = Has energies between 2 to 4 eV</p> Signup and view all the answers

<p>Single-sided camera film = Used in mammography Non-screen film = Used in dental x-rays Plain film imaging = Used most in plain film imaging Screen film = Traditional X-ray film exposure method</p> Signup and view all the answers

<p>Focal spot = Area on the target struck by electrons Line-focus principle = Technique to increase focal spot area without blurring Rotating anode = Anode that can rotate at up to 3600 rotations per minute Filament temperature = Affects the number of electrons accelerated toward the anode</p> Signup and view all the answers

<p>Small focal spot = Produces less image blurring Large focal spot = Concentrates heat on a small area High atomic number target = Increases acceleration of electrons toward the nucleus Kilovolt peak (kVp) = Increases the energy and penetration of electrons</p> Signup and view all the answers

<p>Dense bone = Appears white on X-ray film Soft tissue = Shows up in shades of gray Air = Appears black on X-ray film Fat = Shows up in varying shades of gray</p> Signup and view all the answers

<p>X-ray tube filaments = Used interchangeably to produce different focal spots Anode angulation = Affects the focal spot area and image quality Accelerated electrons = Excite the atomic nucleus and create X-ray photons Vacancy in the K-shell = Filled by an outer shell electron emitting a characteristic X-ray</p> Signup and view all the answers

<p>Small focal spot = Reduces penumbra Close positioning of patient = Reduces object-film distance Increase tube-film distance = Enhances clarity Use grids = Reduces scattered radiation</p> Signup and view all the answers

<p>Increased anode angle = Increases the effective focal spot High kVp = Leads to higher energy X-ray photons Small focal spot usage = Minimizes image blurring but risks overheating Characteristic X-ray production = Depends on the differences in energy levels of electron orbits</p> Signup and view all the answers

<p>Penumbra = Blurred edge of an object in the X-ray image Focal spot size = Size of the X-ray source Object-film distance = Distance from the object to the film Focal-object distance = Distance from the X-ray tube to the object</p> Signup and view all the answers

<p>Holding breath = Reduces motion and blurring Using a grid = Minimizes scattered radiation Using a small focal spot = Decreases penumbra Positioning patient close = Improves sharpness of the image</p> Signup and view all the answers

<p>Continuous X-ray = Another name for Bremsstrahlung X-ray K X-ray photon = Specific to the atom from which it originates Deceleration radiation = A process that emits energy loss as X-ray photons Energetic electrons = More likely to penetrate the region of the nucleus</p> Signup and view all the answers

<p>Increasing filament temperature = Results in more electrons accelerated toward the anode Higher atomic number in target = Enhances the amount of Bremsstrahlung radiation Using a small focal spot = Leads to sharper images with potential heat concentration Rotating anode = Allows for faster rotation and increased efficiency of X-ray production</p> Signup and view all the answers

<p>P = Penumbra width D = Focal spot size L = Focal-object distance l = Object-film distance</p> Signup and view all the answers

<p>Blurring issue = Main problem in obtaining good X-ray image Information representation = Visual form of radiographic image Variation in absorption = Different parts absorb X-rays differently Penumbra width = Can be calculated using a formula</p> Signup and view all the answers

<p>Focal spot size = Influences image blurriness and heat distribution Angulation of the anode = Key factor in the line-focus principle Peak kilovolt (kVp) = Determines maximum energy of produced X-ray photons Filament switch = Allows the choice between small and large focal spots</p> Signup and view all the answers

<p>Reduce blurring = Use a small focal spot Increase sharpness = Position patient close to film Minimize scatter = Incorporate lead and plastic strips Prevent motion = Ensure patient holds breath</p> Signup and view all the answers

<p>Photoelectric Effect = More common in high Z elements Compton Effect = Occurs with loosely outer shell electrons Pair Production = Requires minimum energy of 1.02 MeV Annihilation Radiation = Results from the mass-energy of electrons and positrons</p> Signup and view all the answers

<p>Barium = 56 Iodine = 53 Soft Tissue = 7.42 Air = 0</p> Signup and view all the answers

<p>Iodine Compounds = Show arteries via bloodstream injection Barium Compounds = Orally taken for gastrointestinal tract imaging Oily Mist containing Iodine = Makes airways visible when sprayed into lungs Air = Replaces fluid in brain ventricles for pneumoecephalogram</p> Signup and view all the answers

<p>30 keV = Bone absorbs X-rays better than tissue 100 keV = C.E. occurs more than P.E. in bone Low Z Material = More likely for Compton Effect High Z Material = More likely for Photoelectric Effect</p> Signup and view all the answers

<p>Double-sided radiographic film = Light-sensitive crystals on both sides Digital Radiography = Uses electronic sensors for image capture Computed Radiography = Converts X-rays into images through phosphor plates Film-screen system = Uses a combination of film and fluorescent screens</p> Signup and view all the answers

<p>Barium Enema = Lower GI tract imaging Pneumoecephalogram = Air in brain ventricles Contrast media injection = High Z material in bloodstream Double contrast study = Use of air and barium to show the same organ</p> Signup and view all the answers

<p>Occurs at low energies = Photoelectric Effect Probable in water or soft tissue = Compton Effect Photon colliding produces particles = Pair Production Forms two photons called annihilation radiation = Post-pair production effect</p> Signup and view all the answers

<p>Iodine = Contrast agent for vascular imaging Barium = Contrast agent for gastrointestinal studies Air = Visualizes ventricles of the brain Hydrogen = Not typically used as a contrast agent</p> Signup and view all the answers

<p>Grid = A structure used to absorb scatter radiation in X-ray imaging Filtration = The process of removing low-energy X-rays from the beam Exposure-area product (EAP) = A measure of radiation exposure related to area Ionization = The process of generating charged particles in tissues</p> Signup and view all the answers

<p>Direct interaction = Radiation energy is directly transferred to DNA Indirect interaction = Radiation energy is absorbed by water molecules Scatter radiation = Radiation that deviates from its original path Primary beam = The main X-ray beam that reaches the film or detector</p> Signup and view all the answers

<p>Roentgen (R) = A unit measuring ionizing radiation exposure in air Exposure-area product (EAP) = A quantity describing radiation to the patient C/kg = Unit of measurement for ionization charge in air rap = A unit defined as 100 R cm²</p> Signup and view all the answers

<p>Aluminum = Common material used to filter low-energy X-rays Copper = Material with a higher atomic number used for filtration Lead = Material used in grids to absorb scatter radiation Plastic = Used in grid structures to allow primary beam passage</p> Signup and view all the answers

<p>Increased radiation dose = Grids absorb some primary beam photons Reduced image blurriness = Grids help minimize motion blur effects Enhanced image quality = Grids improve the quality by reducing scatter Patient discomfort = Grids may require longer exposure times</p> Signup and view all the answers

<p>Ionizing radiation = Causes damage to tissues through energy deposition Direct DNA damage = Involves structural changes in DNA molecules Free radicals = Produced from indirect interactions with water Radiation-induced illness = Refers to potential long-term health effects</p> Signup and view all the answers

<p>Abdomen = Thicker body part producing more scatter radiation Pelvis = Another thick body area associated with scatter Lungs = Thinner area resulting in less scatter radiation Skin = Surface area with minimal impact on scatter production</p> Signup and view all the answers

<p>0.6 R = An exposure typical for dental X-rays 100 R cm² = Equivalent to 1 rap in exposure area product 20 R cm² = Exposure received from 0.6 R to 33 cm² area Typical adult exposure = Refers to standard doses received during exams</p> Signup and view all the answers