Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
fluoroscopy
Comprehensive Guide to Fluoroscopy
| Question | Answer |
|---|---|
| Dynamic imaging | Imaging of the functioning or motion of anatomic structures. |
| Fluoroscopy | A technique that uses a continuous or pulsed beam of x-rays to create images of moving internal structures. |
| Image Intensification | The process of enhancing the brightness of an image to improve visibility. |
| Brightness Gain | The ratio of the output phosphor brightness to the input phosphor brightness. |
| Automatic Brightness Control (ABC) | A system that automatically adjusts the x-ray exposure to maintain consistent image brightness. |
| Magnification Mode | A setting that enlarges the image for better visualization, affecting image quality and patient exposure. |
| Charge-Coupled Device (CCD) | A device that converts the output phosphor image for viewing on a display monitor. |
| Digital Fluoroscopy | Fluoroscopy that uses digital imaging technology for enhanced image quality and processing. |
| Flat-Panel Detector Fluoroscopy | A fluoroscopic technology that uses flat-panel detectors for improved image quality and reduced patient exposure. |
| Automatic Exposure Rate Control (AERC) | A system that regulates the exposure rate during fluoroscopy to optimize image quality while minimizing dose. |
| Pulsed Fluoroscopy | A technique that delivers x-ray exposure in pulses rather than continuously, reducing radiation dose. |
| Dose Rates | The amount of radiation exposure received over a specific period. |
| Dose Monitoring | The process of tracking radiation exposure to ensure safety limits are not exceeded. |
| Frame Averaging | A technique that combines multiple frames to reduce noise and improve image quality. |
| Pixel Binning | A process that combines pixels to improve signal-to-noise ratio and image quality. |
| Image Recording | The process of capturing and storing fluoroscopic images for later review. |
| Radiation Safety | Procedures and practices designed to minimize radiation exposure to patients and personnel. |
| Quality Control | The measures taken to ensure the fluoroscopic equipment operates correctly and safely. |
| Last Image Hold (LIH) | A feature that retains the last fluoroscopic image on the display for review. |
| Kerma Area Product (KAP) | A measurement of the total radiation dose delivered to a specific area during fluoroscopy. |
| Minification Gain | The increase in image brightness resulting from a reduction in image size. |
| Flux Gain | The increase in the number of light photons at the output phosphor compared to the input. |
| Spatial Resolution | The ability to distinguish fine details in an image. |
| Virtual Collimation | A technique that uses software to limit the area of exposure without physical collimators. |
| Camera tube/CCD | Charge-coupled device used in imaging. |
| Image intensifier | An electronic vacuum tube that converts the remnant x-ray beam to light, then to electrons, then back to light, increasing the light intensity. |
| Light photons | Particles of light created from x-ray photon energy. |
| Output phosphor | Made of silver-activated zinc cadmium sulfide, it absorbs electrons and emits light in response. |
| Anode | Accelerating anode located at the neck of the image intensifier, maintaining a constant potential of approximately 25 kVp. |
| Electrostatic lenses | Negatively charged circular plates that focus the electron stream toward the output phosphor. |
| Electrons | Particles emitted by the photocathode in response to light stimulus. |
| Photocathode | Made of cesium and antimony compounds, it emits electrons in response to light in a process called photoemission. |
| Input phosphor | Made of cesium iodide, it absorbs remnant x-ray photon energy and emits light proportional to the percentage of x-ray absorption. |
| X-rays | High-energy electromagnetic radiation used in imaging. |
| Under-table X-ray tube | A type of X-ray tube positioned beneath the table for fluoroscopic imaging. |
| Milliamperage (mA) | The unit of current used during imaging, typically lower (0.5-5 mA) in image-intensified fluoroscopy compared to higher values (50 to 1200 mA) in radiographic mode. |
| Timer | A control panel feature that buzzes audibly when 5 minutes of x-ray fluoroscopic time has been used. |
| Dead-man switch | A switch that activates the continuous x-ray beam and must be continuously depressed to produce x-rays. |
| Concave shape | The design of the photocathode and input phosphor that ensures all emitted electrons travel the same distance to the output phosphor. |
| Photoemission | The process by which the photocathode emits electrons in response to light stimulus. |
| Light intensities | Equal to the intensities of the exit radiation and converted to electrons by the photocathode. |
| Diameter of image intensifier tube | Ranges from 15 to 58 cm (6-23 inches), depending on the manufacturer and intended use. |
| Length of image intensifier tube | Approximately 50 cm (20 inches). |
| Output phosphor size | Much smaller than the input phosphor, located at the opposite end of the image-intensifier tube. |
| Image brightness | Maintained throughout the fluoroscopic image due to the design of the photocathode and input phosphor. |
| Electronic video signal | The signal sent to a display monitor for viewing after conversion from image light intensities. |
| Conversion factor | An expression of the luminance at the output phosphor divided by the input exposure rate. |
| Luminance | The SI unit of luminance is the candela per square meter (cd/m²). |
| Input exposure rate | Measured in milligray per second (mGy/s). |
| Conversion factor formula | The conversion factor is cd/m² ÷ mGy/s. |
| Brightness gain value | The numeric conversion factor value is roughly equal to 1% of the brightness gain value. |
| Example of brightness gain | A brightness gain of 20,000 would have a conversion factor of 200. |
| Image-intensified fluoroscopy | Dynamic imaging of internal anatomic structures using an image intensifier. |
| Automatic brightness stabilization (ABS) | Another name for automatic brightness control (ABC). |
| Response time of ABC | ABC is slightly slow in its response to changes in patient tissue thickness and tissue density. |
| Lag in image brightness | Visible to the radiographer as a lag in the image brightness on the monitor as the tower is moved. |
| Focal point in magnification mode | The focal point is shifted farther from the output phosphor. |
| Flux gain formula | Flux gain = Number of output light photons / Number of input x-ray photons. |
| Brightness gain formula | Brightness gain = Minification gain X Flux gain. |
| Input phosphor diameter | Measured as d₁ in the minification gain formula. |
| Output phosphor diameter | Measured as do in the minification gain formula. |
| Example of conversion factor calculation | Conversion factor = Output phosphor illumination (cd/m²) / Input exposure rate (mGy/s). |
| Example input/output phosphor sizes | Input phosphor = 20 cm; Output phosphor = 3 cm. |
| Brightness gain example | For a flux gain of 400, the brightness gain would be 17,760. |
| Magnification factor (MF) | The degree of magnification may be found by dividing the full-size input diameter by the selected input diameter. For example, MF = 30 ÷ 15 = 2x magnification. |
| Distortion | In radiography, distortion is a misrepresentation of the true size or shape of an object. In fluoroscopy, shape distortion can occur due to inaccurate control or focusing of the electrons released at the periphery of the photocathode. |
| Pincushion distortion | Pincushion distortion is an unequal magnification of the image that creates a 'pincushion appearance' and causes a loss of brightness around the periphery of the image. |
| Vignetting | Vignetting refers to the loss of brightness around the periphery of the image, often caused by pincushion distortion. |
| Image noise | Image noise results when insufficient information is present to create the image, often due to an insufficient quantity of x-rays. |
| mA (milliamperes) | mA refers to the quantity of radiation; increasing the mA can help reduce image noise by producing more x-rays. |
| Peripheral falloff | Peripheral falloff is the decrease in brightness around the edges of the image, often associated with vignetting. |
| Electrostatic focusing lenses | These lenses in the image intensifier help to focus the electron stream to create a clear image. |
| Remnant x-ray photons | These are the x-ray photons that exit the patient and are used to create the image in the image intensifier. |
| ABC (Automatic Brightness Control) | ABC automatically increases x-ray exposure to achieve consistent image brightness, compensating for variations in input. |
| Grainy image | A grainy image is a result of insufficient light production due to too few x-rays exiting the patient. |
| Curved photocathode | The curved shape of the photocathode can contribute to distortion in the fluoroscopic image. |
| Small structures visibility | Operating the image intensifier in magnification modes improves the operator's ability to see small structures. |
| Patient dose | The amount of radiation exposure a patient receives during a medical imaging procedure, which can increase with magnification modes. |
| Viewing and recording systems | These systems are part of the imaging chain that can affect the spatial resolution capabilities of fluoroscopic systems. |
| Increased x-ray exposure | Increased x-ray exposure is necessary to compensate for fewer electrons incident on the output phosphor, resulting in more light and electrons. |
| Image-forming information | This refers to the necessary data required to create a clear image; insufficient information leads to image noise. |
| Continuous fluoroscopy | A technique where the operator should intermittently pulse the x-ray beam to minimize radiation exposure. |
| Quantum noise | A phenomenon that occurs when too few x-rays exit the patient, resulting in a 'grainy' or 'noisy' image. |
| Fiberoptically coupled | The method by which a CCD is connected to the output phosphor of the image intensifier. |
| Photosensitive material | Material in each pixel of a CCD that dislodges electrons when stimulated by light photons. |
| Signal storage capacitor | A component in a CCD that stores electrical charge until it is sent as an electronic signal to the display monitor. |
| Row gates | Electrodes between each pixel in a CCD that are charged in sequence to move the signal down the row. |
| Analog signal | A continuous signal that is instantly digitized at the point of image capture from the output phosphor. |
| Detective quantum efficiency (DQE) | A measure of how sensitive a CCD is to a wider range of light intensities. |
| Complementary metal oxide semiconductor (CMOS) | A type of device similar to CCD that has its own amplifier, photodiode, and storage capacitor but is less sensitive to light. |
| Transistors in CMOS | Components that surround each detector element in a CMOS device. |
| Fiberoptic bundle | A bundle of very thin optical glass filaments used to couple the CCD to the output phosphor. |
| Image quality improvement | An advantage of CCD technology due to its higher sensitivity and reduced noise. |
| Geometric distortion | An undesired alteration of the image shape that CCD technology helps to eliminate. |
| Radiation dose reduction | A benefit of using CCD technology, which requires less radiation in the system. |
| Electrical charge generation | The process by which a CCD generates an electrical charge when stimulated by light. |
| Capacitor in CCD | A component that stores the electrical charge generated by the photosensitive material. |
| Light intensity | The amount of light that stimulates the photosensitive material in a CCD. |
| Video signal | The output produced by television camera tubes before the advent of CCD electronics. |
| Solid-state device | A type of electronic device that uses semiconductor materials, like CCDs. |
| Image processing | The method of converting and enhancing the captured image for display. |
| Flat-panel technology | A technology that replaces conventional image intensifiers, producing a digital signal directly without the need for a CCD. |
| Flat-panel detectors (FPD) | Devices that are lighter and more compact than intensifiers, producing a digital signal directly and resulting in less electronic noise. |
| Field-of-view (FOV) | The size of the area that can be imaged, currently available in sizes of 25 × 25 to 43 x 43 cm (10 x 10 to 17 x 17 inches). |
| Image quality drawbacks | Issues with image intensifiers such as blooming, peripheral falloff, and vignetting due to the design of the curved input surface and internal geometry. |
| Dynamic range | The range of tissue visibility and contrast resolution that can be viewed, which is greater with FPD fluoroscopy. |
| Dose efficiency | The ability of FPD fluoroscopy to reduce fluoro doses by as much as 50% compared to intensified fluoroscopy. |
| Contrast resolution | The ability to distinguish between different tissue types, which is increased with flat-panel detectors. |
| Dynamic response | The capability of a system to respond to subtle tissues, which is greater in flat-panel detectors than in image intensifiers. |
| Interventional studies | Procedures that may require the rotation of the rectangular or square flat-panel to better match the orientation of patient anatomy. |
| Scintillator | A material used in FPD fluoroscopy, which may be cesium iodide or gadolinium oxysulfide, contributing to high DQE in its design. |
| Thin-film transistor (TFT) technology | A technology used in flat-panel detectors that enhances image quality and reduces electronic noise. |
| Patient anatomy positioning | The requirement for careful positioning within the center of the intensifier window for optimum resolution with image intensifiers. |
| Image intensifier aging | The deterioration of image quality and increased dose requirements for acceptable image quality as intensifier tubes age with use. |
| Blooming | An image quality problem where bright areas spread into surrounding darker areas, more prevalent in image intensifiers. |
| Clinicians' applications | The increasing use of FPD fluoroscopy in clinical settings due to its superior image quality and efficiency. |
| Flat-panel detectors | The flat-panel detector used for fluoroscopic applications is the indirect-capture detector. |
| Photodetector | The photodetector is amorphous silicon, which is a liquid that can be painted onto a substrate and is the material that makes flat-panel detectors possible. |
| Thin-film-transistor (TFT) array | TFTs are electronic components layered onto a glass substrate that includes a readout, charge collector, and light-sensitive elements. |
| Detector elements (DELS) | The panel is configured into a network of detector elements covered by the scintillator plate with each DEL containing a photodetector and a TFT. |
| Dynamic image | Dynamic versions of these detectors must respond in rapid sequences to create a dynamic image. |
| Frames per second (fps) | Current dynamic versions are capable of up to 60 frames per second. |
| Rapid readout speeds | Necessary for how the active matrix processes the image data. |
| Two-dimensional (2D) rectilinear array | The panel design is a two-dimensional rectilinear array of DELS that can be electronically processed line by line in a fraction of a second. |
| Very-low-noise flat-panel detector systems | Needed for fluoroscopic applications to prevent operational noise from degrading the fluoroscopic image. |
| Application-specific integrated circuits (ASICS) | Used to minimize noise and amplify signal from the active matrix. |
| Fill factor | The area of each DEL that is sensitive to x-ray detection materials. |
| Low-dose output | Fluoroscopy generally operates at a low-dose output; hence, any operational noise degrades the fluoroscopic image. |
| Light-emitting diode array | A backlighting system incorporated to erase the detector between frames to prevent ghosting caused by any residual exposure charge from the previous frame. |
| Ghosting | Caused by any residual exposure charge from the previous frame. |
| Static imaging | High-dose inputs are used for static imaging. |
| Fluoroscopic applications | Require very-low-noise flat-panel detector systems due to low radiation doses used. |
| Indirect-capture detectors | These detectors are particularly important in fluoroscopic applications. |
| X-ray energy absorption | With this system, x-ray energy is absorbed by the scintillator and converted to light energy. |
| Electrical charges | Light is absorbed by the photodetectors and converted to electrical charges. |
| Analog to digital signal | Electrical charges are captured and transmitted by the TFT array, converted from an analog to digital signal for image processing. |
| Display monitor | The final output for viewing the processed image. |
| Flat-panel detector systems | Advanced imaging systems used in fluoroscopy that require very-low-noise for optimal image quality. |
| Light-emitting diode array backlighting system | A system used to erase the detector between frames to prevent ghosting from residual exposure charge. |
| Source-to-image receptor distance (SID) | The distance between the x-ray source and the image receptor, variable from 100 to 180 cm (40 to 72 inches). |
| Table-side fluoroscopy | A design where the x-ray tube is positioned under the patient with the flat-panel detector above. |
| Remote-controlled fluoroscopic systems | Fluoroscopic systems that allow the radiologist to operate controls from a lead-lined control booth. |
| Scatter radiation | Radiation that is scattered from the patient during fluoroscopy, posing a risk to personnel. |
| Lead apron | A protective garment worn by personnel to shield against scatter radiation during fluoroscopy. |
| Upright studies | Radiographic examinations performed with the patient in an upright position. |
| Trendelenburg position | A position where the patient is laid back with the legs elevated, used in certain radiographic procedures. |
| Radiographic detector | A device used to capture images in radiography, often integrated with fluoroscopic systems. |
| Intercom speaker and microphone | Communication devices used by the radiologist to interact with the patient during fluoroscopy. |
| Economics of fluoroscopy systems | The cost-effectiveness of using a single flat-panel detector for both fluoroscopy and radiography. |
| Radiographic and fluoroscopic controls | Controls that manage both radiography and fluoroscopy, typically located behind a lead-lined booth. |
| X-ray tube positioning | The arrangement of the x-ray tube relative to the patient, which can affect image quality and radiation exposure. |
| Patient radiation exposure | The amount of radiation the patient receives during fluoroscopic imaging, which is a primary concern. |
| Fluoroscopic personnel exposure | The radiation exposure experienced by medical staff during fluoroscopic procedures. |
| Digital R/F system | A system with an x-ray tube located above the patient. |
| Flat panel digital detector | A device used to capture x-ray images in digital form. |
| Scatter area | The region where scatter radiation is directed, affecting operator exposure. |
| Fluoroscopic features | Characteristics of modern fluoroscopic equipment that impact image quality and radiation dose. |
| kVp | Kilovolt peak; a setting that influences the energy of the x-ray beam and patient dose. |
| Collimation | The process of reducing the x-ray beam field size to limit patient exposure. |
| Field of view (FOV) | The area visualized in the fluoroscopic image, which can be adjusted by collimation. |
| Operator anatomy protection | The use of a fluoroscopic lead apron to protect the operator from radiation. |
| Grid | A control feature that reduces scatter reaching the detector and improves image quality. |
| mA | Milliamperes; a measure of the quantity of radiation used in imaging. |
| Filtration thickness | The thickness of added filtration material that can be adjusted in fluoroscopic units. |
| Aluminum | The typical material used for beam filtration to remove low-energy x-ray photons. |
| Radiation dose | The amount of radiation exposure received by the patient during an examination. |
| Anatomic area capacity | The ability of a specific body area to produce scatter radiation. |
| Pediatric patients | Children who may not require the use of a grid due to lower scatter production. |
| Extremities | Limbs that may not require the use of a grid in fluoroscopic examinations. |
| Radiation safety practice | Understanding scatter radiation areas to protect fluoroscopic staff. |
| Patient dose reduction | The process of minimizing radiation exposure to the patient through various techniques. |
| Exposure maintenance | The adjustment of mA to maintain overall exposure to the detector when using a grid. |
| Filtration | Acts to increase the average energy of the beam by removing low-energy photons. |
| Beam Hardening | The process of using higher atomic materials such as copper to increase the quality of the beam. |
| Spectral Filtration | Advancements in the type and combination of materials used in filtration incorporated into modern fluoroscopic equipment. |
| Anatomic Programs | Preset fluoroscopic examination settings established and programmed into the unit at the time of manufacture or installation. |
| Default Settings | Intended to be 'ideal' or 'standard' values for minimizing dose and maximizing image quality. |
| Patient Thickness | A variable that can result in changes in the radiation exposure reaching the flat-panel detector. |
| Tissue Attenuation | A factor that can affect the radiation exposure during a fluoroscopic examination. |
| Object-to-Image Receptor Distance (OID) | A variable that may require adjustments in radiation reaching the detector. |
| Pulse Rate | Refers to how many pulses occur per second of operation. |
| Pulse Width | The length of each pulse during pulsed fluoroscopy. |
| Pulse Height | The level of mA per pulse in pulsed fluoroscopy. |
| Pulse Interval | The time in milliseconds (ms) between successive mA pulses. |
| Signal-to-Noise Ratio (SNR) | A measure that must be maintained for image quality during fluoroscopy. |
| Contrast-to-Noise Ratio (CNR) | Another measure that must be maintained for image quality during fluoroscopy. |
| Dynamic Motion Characteristics | The characteristics of the area being studied that require correlation with selected pulse rates. |
| Fast-Moving Anatomy | Anatomy such as the heart and chest structures that requires a faster pulse rate. |
| Slow-Moving Structures | Anatomy such as orthopedic fracture repair that can be studied with a slower pulse rate. |
| Frame per second (FPS) | A measurement of the number of images displayed in one second, which can vary in pulsed fluoroscopy (e.g., 30 FPS, 15 FPS, 7.5 FPS). |
| Air kerma | The intensity of x-rays at a given point in air at a known distance from the focal spot, monitored during fluoroscopic procedures. |
| Dose area product (DAP) | A measure of exposure in air that estimates the absorbed dose to the patient, required on all new fluoroscopes. |
| Cumulative air kerma | Also referred to as reference dose, it estimates the total patient skin dose for the fluoroscopic procedure, measured in Gy. |
| Fluoroscopic exposure rate | A quality control measure that should not exceed approximately 88 mGy/min or 10 R/min in the United States. |
| Radiation dose units | Units such as DAP or KAP and reference dose that should be monitored during fluoroscopic procedures. |
| Total fluoro time | The total amount of time spent using fluoroscopy during a procedure, which should be documented in the patient's record. |
| Patient radiation dose | The amount of radiation exposure a patient receives during a fluoroscopic procedure, which can be reduced by using pulsed fluoroscopy. |
| Dynamic motion of patient anatomy | The movement of the patient's body that pulsed fluoroscopy must match to provide effective imaging. |
| Quality fluoroscopic image | An image that maintains clarity and detail, requiring sufficient x-ray exposure and appropriate settings. |
| Radiographer's responsibility | Monitoring and documenting radiation dose units in the patient's medical record during fluoroscopic procedures. |
| Radiation dose threshold | An agreed-upon limit for radiation exposure that, if reached, requires notification of the operator. |
| Micro or milligray (Gy) | Units of measurement for radiation dose, which can vary by manufacturer. |
| 1 μGy-m² = 1 cGy-cm² = 10 mGy-cm | A conversion relationship between different units of radiation dose measurement. |
| 1 centimeter squared (cm²) | A unit of area measurement equivalent to 0.0001 m². |
| Frame rate | The frequency at which video frames are displayed, with a standard rate of 30 frames per second (fps) perceived as continuous video by the human eye. |
| Temporal resolution (TR) | A measure of how well a system can resolve changes in time, which decreases with increased frame averaging. |
| Image smearing | A phenomenon that occurs when averaging more frames per unit of time, leading to a loss of clarity in dynamic images. |
| DELS | Detector elements that serve as charge collection units in digital fluoroscopy. |
| Pulsed exposures | X-ray exposures that are delivered in pulses at selected pulse rates during digital fluoroscopy. |
| Refreshing | The process of recharging a DEL after it has been read out following an x-ray exposure. |
| File size data rate | The amount of data generated per second during imaging, which can increase significantly with higher frame rates. |
| Binning combinations | The arrangements of DELS working together, which can be 2×2, 3×3, or 4×4, affecting image resolution and SNR. |
| Fluoroscopic acquisition | An imaging process that may run for a limited time, generating substantial file sizes based on frame rates. |
| Video noise | Unwanted variations in brightness or color in video images, which can be reduced through frame averaging. |
| Continuous video image | The perception of a seamless video display created by rapidly displayed frames at a sufficient frame rate. |
| Dynamic images | Images that depict moving anatomical structures, which require careful consideration of TR and frame averaging. |
| Image clarity | The quality of an image in terms of sharpness and detail, which can be compromised by excessive frame averaging. |
| Radiation efficiency | The effectiveness of an imaging system in producing quality images with minimal radiation exposure. |
| Dose monitoring units | Units that may vary by manufacturer for measuring radiation dose during imaging procedures. |
| Binning | A process that groups and averages adjacent detector elements (DELS) to reduce noise in fluoroscopic imaging. |
| Electronic Magnification | The selection of a smaller FOV that enlarges an area smaller than the detector size to fill the display monitor, enhancing the visibility of anatomical structures. |
| Liquid Crystal Display (LCD) | A type of display monitor that offers superior resolution and brightness compared to conventional cathode ray tube (CRT) monitors, consisting of layers with nematic liquid crystals. |
| Nematic Liquid Crystals | Rod-shaped, semiliquid crystals used in LCDs that can change the direction of light when an electric current is applied. |
| Twisted State | The unorganized state of liquid crystals in an LCD before an electric current is applied. |
| TFT Panel | A thin-film transistor panel located behind the liquid crystal layer in an LCD, with the number of TFTs equal to the number of pixels displayed. |
| Fast Fluoroscopic Framing Sequence | A rapid series of images captured during fluoroscopy that can benefit from reduced DELS operation through pixel binning. |
| Magnification Modes | Different settings available on flat-panel detectors that allow for varying levels of image enlargement during fluoroscopy. |
| Unpolarized Electromagnetic Radiation (EMR) | Light waves that travel in multiple planes before being manipulated by the liquid crystal layer in an LCD. |
| Polarizing Filters | Layers in an LCD that control the passage of light based on the orientation of the liquid crystals. |
| Electric Current | A flow of electric charge that, when applied to the liquid crystal layer, alters the orientation of light passing through the LCD. |
| Image Quality | The clarity and detail of an image, which can be enhanced through the use of advanced display monitors and imaging techniques. |
| Patient Radiation Exposure Rate | The rate at which radiation is delivered to a patient during imaging, which can be slightly increased with certain imaging techniques. |
| High-Resolution Monitors | Modern display devices that provide enhanced clarity and detail for viewing fluoroscopic images. |
| TFTs | Thin-film transistors that control the current to each pixel in an LCD monitor. |
| Monochromatic LCD monitor | Displays light as shades of gray. |
| Color LCD monitor | Has a color filter layer added to display shades of color. |
| Megapixels (MP) | A measurement used to express the resolution of LCD monitors, with radiologists typically interpreting images using 5 MP displays or greater. |
| Fluoroscopic images | Images that have improved quality (less noise) than traditional fluoroscopic images but result in significantly increased patient radiation exposure. |
| LIH | Last image hold feature that saves single images or a fluoro sequence loop to memory. |
| Mobile C-arm units | Fluoroscopic units typically used in the operating suite or emergency department for imaging during nonroutine procedures. |
| C-arm unit | Designed with an x-ray tube and image intensifier or digital detector attached in a C configuration, allowing for various positioning. |
| Mini C-arm | Provides a lower dose rate and greater equipment flexibility while providing quality images of extremities. |
| Radiation safety measures | Practices that the radiographer must monitor and apply during fluoroscopy in an uncontrolled environment. |
| Fluoro loop save | A feature that saves a sequence of fluoroscopic images to memory. |
| Image intensifier tower | A component of the C-arm that enhances the quality of the images produced. |
| Control cart | Contains controls for operating the C-arm and managing imaging procedures. |
| Static and dynamic imaging | Types of imaging offered by display monitors during procedures. |
| C-arm positioning | Allows for movement in various planes, enabling viewing from different perspectives. |
| Three sets of locks | Provided to move and hold the C-arm in place during imaging procedures. |
| Patient positioning | Refers to the arrangement of the patient in relation to the C-arm during imaging. |
| Radiographic mode | A mode that can be switched to from fluoroscopy quickly and is controlled by fluoroscopic system controls. |
| Noise in images | Increased in saved fluoroscopic images but significantly less exposure to the patient. |
| Flat-panel detector | A type of imaging detector that is smaller and lighter, enabling portable C-arm systems. |
| O-arm system | An imaging system that provides both static and dynamic images along with two- and three-dimensional (3D) images, using two flat-panel fluoroscopic detectors in an orthogonal orientation. |
| Radiation dose reduction methods | Techniques such as omission of the grid, minimal use of magnification, and using LIH to reduce radiation exposure during fluoroscopy. |
| Pulsed x-ray exposure | A method of controlling x-ray exposure by intermittently pulsing the x-ray beam to reduce patient and personnel exposure. |
| DAP or KAP | Dose Area Product or Kerma Area Product, metrics used to quantify radiation exposure during fluoroscopic procedures. |
| Control panel timer | A device feature that produces an audible noise after 5 minutes of x-ray fluoroscopic time has been used. |
| Motor controlled equipment | Imaging equipment that allows for controlled movement to facilitate patient access and imaging. |
| Open architecture C-arm | A design that uses two orthogonal digital receptors without motorization, allowing for easier positioning around the patient. |
| Fluoroscopic and radiographic images | Images obtained using flat-panel detector technology that allow assessment of the procedure outcome before closing the patient. |
| Exposure switch or pedal | A device used to control the activation of x-ray exposure during fluoroscopic procedures. |
| Standard radiation safety practices | Time, distance, and shielding methods employed to minimize radiation exposure during imaging. |
| Patient access | The ability to easily reach and position the patient during imaging procedures. |
| Specialized draping | Techniques used to maintain sterility during imaging when the gantry is closed. |
| Vascular lines and orthopedic devices | Medical devices such as pins, rods, and fixation plates that require precise placement during surgical procedures. |
| Cumulative fluorotimer | A monitoring feature in modern fluoroscopic units that tracks the total amount of x-ray fluoroscopic time used. |
| Intermittent pulsing | A technique where the operator applies pressure to the exposure switch or pedal in a non-continuous manner to reduce radiation exposure. |
| Fluoroscopic imaging needs | The various imaging requirements during surgical procedures that necessitate different imaging modalities. |
| Gantry | The structure of the imaging system that houses the detectors and allows for movement around the patient. |
| Cumulative exposure time | The total duration of exposure to radiation that needs to be documented when monitoring systems are not available. |
| Intensity of x-ray exposure | Should not exceed 88 mGy/min (10 R/min) for routine fluoroscopic units equipped with ABC. |
| Source-to-skin distance (SSD) | Should be no less than 38 cm (15 inches) for stationary fluoroscopic units and no less than 30 cm (12 inches) for mobile C-arm fluoroscopic units. |
| OID | The distance between the patient and the radiation detector, which should be decreased to reduce patient exposure. |
| Static images | Decreasing the number of static (radiographic) images will reduce patient exposure. |
| Lead aprons | Recommended thickness of 0.5 mm of lead equivalent for personnel in the fluoroscopy room. |
| Receptor tray slot cover | Must have at least 0.25 mm of lead equivalent and automatically cover the opened space at the side of the table. |
| Protective lead curtain | Must be placed between the patient and the operator and have at least 0.25 mm of lead equivalent. |
| Intermittent exposure | Operating the fluoroscopic exposure intermittently minimizes patient radiation dose. |
| Last image hold | A technique that minimizes patient radiation dose by holding the last image displayed. |
| Preset settings | Evaluating and using available preset or default settings can help minimize patient dose. |
| Total x-ray fluoroscopic time | Should be monitored and documented in 5-minute increments on the control panel. |
| Cumulative radiation dose data | Should be recorded if provided during fluoroscopic procedures. |
| ALARA principle | Maximizing distance to a practical level is a very effective practice for minimizing exposure. |
| Quality control programs | Vitally important for monitoring equipment performance and minimizing patient dose from ionizing radiation-producing equipment. |
| ABC | Automatic brightness control used in fluoroscopic units to maintain image quality. |
| AERC | Automatic exposure rate control that helps manage radiation exposure during fluoroscopy. |
| Patient as source of exposure | During fluoroscopy, the patient is the source of occupational exposure to radiation. |
| Distance from patient | Personnel should increase their distance from the patient to reduce exposure to scatter radiation. |
| Fluoroscopic equipment | Used extensively in health care and contributes significantly to the radiation dose received by the general population. |
| Operational inspection | Conducted using a checklist of items found in Box 10.3 at least every 6 months. |
| Fluoroscopic Equipment Inspection Checklist | A checklist that includes items such as Bucky slot cover, protective curtain, tower locks, power assist, control panel, and exposure switch. |
| Bucky slot cover | Should expand and cover the entire opening when the receptor tray is parked at the foot of the table. |
| Protective curtain | Should be in good condition and move freely into place when the tower is moved to the operating position. |
| Tower locks | Should be in good working order. |
| Power assist | Moves the tower about easily in all directions. |
| Control panel indicator lights | Should be operational. |
| Exposure switch (dead-man switch) | Should not stick and operate the x-ray tube only while in the depressed position. |
| Collimator shutters | In the fully open position, should restrict the beam to the size of the input phosphor and be accurate to within ±3%. |
| Fluoroscopic timer | Should buzz audibly after 5 minutes of fluoroscopic 'beam-on' time. |
| Monitor brightness | Adjusted to display as many of the penetrometer steps as possible during exposure. |
| Table tilt motion | Should tilt smoothly to its limit in both directions, and the angulation indicator should be operational. |
| Fluoroscopic system resolution | Tests the system's ability to display details of small objects (high-contrast resolution) and larger objects (low-contrast resolution). |
| Fluoroscopic ABC/AERC performance | Evaluates image quality for changes in exposure parameters such as high dose rate, pulsed modes, and FOV. |
| Fluoroscopic phantom image quality | Evaluates the quality of the displayed fluoroscopic image, including image distortion or lag. |
| Fluoroscopic exposure rates | Measures the intensity of the x-ray beam; fluoroscopic exposure rate should not exceed -88 mGy/min (10 R/min). |
| Fluoroscopic alignment test | Ensures the radiation beam aligns with the center of the image intensifier or flat-panel detector within 2% of the SID. |
| Patient dose monitoring system calibration | Evaluates proper function of patient dose monitoring systems such as DAP meters. |
| Display monitor performance | Evaluates the display characteristics of the monitor. |
| DAP | Dose area product. |
| FOV | Field of view. |
| SID | Source-to-image receptor distance. |
| Multifield Mode | A mode provided by image intensifiers that magnifies the image, improving spatial resolution but increasing patient exposure. |
| Spot Filming | Flat-panel detectors replace spot filming and other recording devices, capable of operating in radiographic mode. |
| Digital Fluoroscopy mA | Uses a higher mA range of 50-1200 mA to maintain sufficient exposure to the IR for a diagnostic image. |
| Pulsed X-ray Beam | Modern fluoroscopic units use a pulsed x-ray beam, unlike older units that operated continuously. |
| AERC (Automatic Exposure Rate Control) | A feature of modern fluoroscopic units that allows selection of dose rates and other exposure factors. |
| LCD Monitors | Preferred display technology for fluoroscopy, offering superior resolution and brightness. |
| Mobile C-arm | A specialized fluoroscopic unit available for use outside the radiology department. |
| Radiation Safety Practices | Include reducing fluoroscopic time and shielding the operator with protective equipment. |
| SSD (Source-to-Skin Distance) | Should be not less than 38 cm (15 inches) for stationary units and 30 cm (12 inches) for mobile units. |
| X-ray Exposure Limit | The intensity at the tabletop should not exceed -88 mGy/min (10 R/min). |
| Quality Control Procedures | Important for monitoring the performance of the fluoroscopic unit. |
| SSD | Should not be less than 30 cm (12 inches) when operating a stationary fluoroscopic unit. |
| X-ray exposure at the tabletop | Should not exceed 1.0 R/min during fluoroscopy. |
| Numeric conversion factor | Value is equal to 0.01 of the brightness gain value. |
| Brightness gain of 40,000 | Would have a conversion factor of 4000. |
| Magnification mode disadvantage | Increased patient exposure. |
| Combination reducing patient radiation exposure | Lowest pulse mode and lowest dose rate. |
| Input surface of a fluoroscopic imaging detector | Referred to as the photoemissive surface. |
| Improving noisy fluoroscopic image quality | An effective method is to select pixel binning on the control. |
| Scatter radiation exposure to the operator | Greatest below the waist in a fluoroscopic system with the x-ray tube above the patient. |
| Dynamic fluoroscopy of fast-moving anatomy | Application of pulsed fluoroscopy will require faster pulse rates and shorter pulse intervals. |
Created by:
user-2019507
Popular Radiology sets