Radiography Overview

Chapter 1

• X-rays were discovered in 1895 by Roentgen
• Radiographs are the proper term for the "pictures" produced by x-rays
• The American Society of Radiologic Technologists (ASRT) is the world's oldest and largest radiologic science professional organization
• The American Registry of Radiologic Technologists (ARRT) establishes standards and provides certification examinations for radiologic technologists
• RT (R) stands for Registered Technologist (Radiography)
• JRCERT formally conducts accreditation of education programs in radiologic technology
• Fluoroscopy is the imaging modality that provides real-time viewing of x-ray images in motion
• To determine the credentials needed to practice limited radiography, contact the State Department of Health
• Limited radiography is called limited because scope of practice is limited
• Within the scope of practice for a limited operator is basic radiographic examination and explanation of procedures
• Angiography is the imaging modality uses contrast media to image blood vessels
• Consequences for practicing beyond the scope of practice of a limited operator could be monetary fines, revocation of license/permit, and imprisonment
• Reciprocity means credentials issued in one state are recognized in another state
• Performing mammograms in a private physician's office qualifies as practicing beyond the scope of a limited operator
• X-ray examinations are performed on orders issued by physicians
• A duty of a limited x-ray machine operator is to explain the procedure and the preparation to the patient
• A medical doctor who diagnoses and treats disorders and diseases of the feet is called a podiatrist
• JRCERT began to accredit limited scope x-ray machine operator educational programs
• The nationally accepted, and most often used, term for the limited x-ray operator is limited x-ray machine operator
• Bone densitometry is the specialized area of radiology that uses x-rays to measure the bone mineral content and density of bones

Chapter 2

• X-rays that leave the x-ray tube exit via the tube port
• The control booth is the portion of the x-ray room that is protected from scatter radiation and is safe during exposures
• A line in the center of the x-ray beam and perpendicular to the long axis of the x-ray tube is called the central ray
• An IR that has been exposed to a body part but has not yet been processed has an unseen image called the latent image
• Tissues with greater mass, such as bone, will absorb more radiation, when compared with less dense tissues, such as fat
• Attenuation is the absorption of x-rays by matter
• Scatter radiation has less energy than the primary beam
• Remnant radiation is the varying intensity of radiation that exits the patient and reaches the IR
• The image receptor (IR) usually consists of a cassette and phosphor imaging plate
• Primary radiation exits the x-ray tube and travels in air to the patient
• In computed radiography (CR), the image is originally obtained and stored in a phosphor material
• A collimator is the boxlike device attached under the tube housing that allows the limited operator to vary the size of the radiation field
• A grid or bucky is a device to protect the IR from being fogged by scatter radiation
• The patient is the principle source of scatter radiation
• A tilting table will allow the head end to be lowered at least 15 degrees into the Trendelenburg position
• Scattered radiation is primary radiation that enters the patient and then leaves it, traveling in all directions
• Scatter radiation fog is unwanted image exposure caused by scatter radiation
• After an x-ray is taken and the image is stored in the computed radiography plate, it has to be processed in the image reader device
• Falling is the most frequent adverse incident that can happen to a patient in the radiology department
• A detent is a mechanism that tends to stop a moving part in a specific location

Chapter 3

• mAs 1 / mAs 2 = (SID1)2 / (SID2)2 is the formula for changing mAs to maintain a constant intensity when distance (SID) changes
• 200 is the mAs when 400 mA is used with a 0.5 second exposure time
• If a satisfactory AP shoulder radiograph is made on a patient measuring 12 cm using 70 kVp, the most similar radiograph of a patient whose shoulder measures 16 cm will be produced using 78 kVp
• A satisfactory lateral lumbar spine radiograph is taken using 120 mAs and 40 inches SID; if an increase in SID to 60 inches is desired, a technique change to produce a similar radiographic density will be 270 mAs
• To compensate for a 2-cm increase in patient part size, multiply mAs by 1.3 (30%)
• A satisfactory AP lumbar spine radiograph made using 50 mAs and 78 kVp will have a similar density and less contrast/exposure with 25 mAs, 90 kVp using the 15% rule
• With an x-ray exposure made using 300 mA and 0.02 seconds, the value of the mAs is 6
• When the SID is doubled, the intensity of the radiation in the radiation field is reduced by a factor of 4
• A satisfactory radiograph is made using 100 mA and 0.2 seconds; to produce a similar radiograph when using 400 mA, an exposure time of 0.05 sec is required
• A satisfactory radiograph is made using 60 mAs and 72 inch SID; to produce a similar result at 40 inches SID, use 18 mAs
• A satisfactory image is made using 200 mA and 0.05 sec; to produce a similar mAs, use 400 mA and .025 sec
• 3 kVp/cm compensates for patient size changes when kVp is greater than 85

Chapter 4

• Atoms are the building blocks of all matter
• The K shell in an atom would contain the least number of electrons
• Electrons are located in an orbit around the nucleus of an atom
• Protons have a positive charge
• The K shell in the atom is most important in x-ray production
• When an electron is removed from an atom, the atom is ionized
• The K electron shell in the atom has the greatest binding energy
• The atomic number of an atom is represented by the number of protons
• Wavelength is the distance from one crest to the next in a sine wave
• The frequency of a sine wave is measured by the number of times per second that a crest passes a given point
• Of the types of electromagnetic energy, X-rays has the shortest wavelength
• X-rays can penetrate matter
• All electromagnetic energy moves through space at the same velocity
• The smallest possible unit of electromagnetic energy is the photon
• Current applies to the quantity of electrons flowing through a circuit
• Potential difference refers to the force or strength of the electron flow in the current
• The unit used to measure the rate or volume of current flow is the ampere
• The volt is the unit of potential difference
• The standard voltage provided by utility companies for household use is 120 volts
• In radiology, 80,000 volts is converted to 80 kVp
• The milliamperage used in radiology is 25 to 500
• In radiology, high-frequency generators can use up to 6,000 Hz of electrical frequency
• Direct current flows in only one direction
• The frequency of alternating current delivered by electrical utilities in the United States and Canada is 60 Hz
• The purpose of a transformer is to increase or decrease voltage
• Step-down transformers would have more windings on the primary side
• If the voltage across the primary side of a step-up transformer is 100 V and the transformer has a 500:1 ratio, the voltage on the secondary side is 50,000
• Tungsten is one of the most important elements in radiology
• Electromagnetic x-rays have short wavelengths and high frequency
• Rectification is the process of converting alternating current into direct current for x-ray production
• Electromagnetic induction is when electricity is produced when a magnet is moved around a conductor or the conductor is moved around the magnet

Chapter 5

• The x-ray tube inside the protective house is made of Pyrex glass
• The four essential elements required for x-ray production are a target, a vacuum, an electron source, and a high potential difference
• A coil of tungsten wire is the filament of an x-ray tube
• The target of the x-ray tube is made of tungsten
• A filter is a device for removing long wavelength (low energy) radiation from the primary beam
• A space charge is the electron cloud that surrounds the hot cathode
• Free electrons at the cathode that are used for x-ray production come from the filament
• Thermionic emission is when tungsten atoms are heated, their outermost electrons are moved out of the atom in space
• The anode is positively charged
• The cathode is negatively charged
• Most x-ray tubes in use today have a standard rotation speed of 3,600 rpm
• More efficient heat dissipation is the principal advantage of a high-speed rotating anode
• Bremsstrahlung radiation makes up the greatest portion of the x-ray beam
• A high potential difference is required to move the electron stream rapidly across the x-ray tube
• More than 99% of the energy applied to an x-ray tube is converted into heat
• Bremsstrahlung radiation is produced in the anode by the sudden slowing and directional change of an incoming electron
• Characteristic radiation is produced when an incoming electron interacts with the K-shell electron in the tungsten atom
• The degree of angulation of the x-ray tube target determines the effective focal spot
• A smaller effective focal spot produces greater image sharpness
• A larger actual focal spot produces greater tube heat capacity
• The anode heel effect is a phenomenon of x-ray production that results in an uneven distribution of radiation within the field
• Kilovoltage controls the penetrating power of the x-ray beam
• Milliamperes is the unit the current across the x-ray tube is measured in
• The mAs used for an exposure determines the quantity of radiation in the exposure
• If 400 mA and 0.02 sec are used for an exposure, the mAs is 8
• When exposure time is very short, the time is usually measured in milliseconds
• If an exposure time is measured in 35 milliseconds, the time in seconds is 0.035
• The x-ray beam is made up of many different energy x-rays and is referred to as heterogeneous
• Tungsten has a high melting point
• X-ray equipment capable of producing 70 kVp or more must have 2.5 mm Al eq of equivalent aluminum filtration
• Lowering patient dose is the primary advantage of x-ray beam filtration
• A steeper target angle provides a smaller effective focal spot
• Filtration decreases the average wavelength of the x-ray beam
• The focal spot is the precise area on the target where electrons strike
• The electromagnetic induction motor is used in the x-ray machine to rotate the anode
• The difference in the x-ray intensity (or volume of x-rays) between the anode and the cathode side of the x-ray beam is 75%
• mAs primarily controls the density of the radiographic image
• kVp primarily controls the contrast of the radiographic image
• Aluminum is used as added filtration in the x-ray tube

Chapter 6

• The x-ray circuit is divided into the low-voltage, filament, and high-voltage circuits
• The autotransformer is primarily used for variable kVp selection
• The power to the x-ray room is usually 220 V
• mA control on the x-ray generator adjusts heat the filament in the x-ray tube
• The purpose of the filament circuit supplies the filament with heat for thermionic emission to occur
• Step-down transformers reduces the voltage on the secondary side to provide an appropriate current to heat the filament
• Electronic timers are typical of exposure times that are as low as 0.001 sec
• Rectification is the process of changing alternating current to direct current
• The purpose of a diode in an x-ray circuit is to electronically convert AC to DC
• The x-ray tube is located on the high-voltage side of the x-ray circuit
• High-frequency generators produce x-rays more efficiently when compared to 1-phase and 3-phase generators
• A series of warm-up exposures is made on a cold x-ray tube to prevent damage to the anode from sudden heating
• To prolong x-ray tube life, the tubes should be operated at about 80% capacity
• The maximum heat capacity of the anode of the tube is rated in terms of heat units
• mA x time x 1.35 calculates the heat produced by an exposure made on a 3-phase generator
• Nearly all new x-ray machines manufactured today use high frequency generators
• In a high-frequency generator, the incoming 60 Hz electrical frequency is raised to 6,000 Hz
• Automatic exposure control terminates the exposure time after an exact amount of radiation for a given body part has been detected
• Anatomically programmed radiography (APR) are x-ray generators that are programmable in which the exposure factors from the technique chart can be programmed into the generator
• When using automatic exposure control (AEC) for setting exposure techniques, exposure time does not have to be set
• Public law 90-602 states that generators must terminate the exposure at 600 mAs
• Patient positioning must be absolutely accurate when using AEC for exposure technique
• If the automatic exposure system fails during an exposure, the back up timer will terminate the exposure
• Density control on the x-ray generator override the AEC system when an exposure is over/underexposed
• Technique charts are not necessary for APR
• High frequency x-ray generators produce the greatest amount of heat for the same exposure technique
• The tube rating chart determines the x-ray tube capacity for a single exposure

Chapter 7

• Milliamperage, exposure time, kilovoltage and distance (SID) are the prime factors of exposure in radiography
• mAs is the unit used to indicate the total quantity of x-rays in an exposure
• Two exposures are made using the following technical factors: Image A: 500 mA, 0.05 seconds, 72 kVp & Image B: 200 mA, 0.125 seconds, 72 kVp; both images exhibit equal density
• Decrease mAs to correct an overexposed radiographic image
• The inverse square law expresses the relationship between SID and x-ray beam intensity
• The inverse square law governs the relationship between x-ray beam intensity and distance
• The inverse square law states that the intensity of the x-ray beam is inversely proportional to the square of the distance
• Density, contrast, distortion and spatial resolution (detail) the four primary aspects of radiographic quality
• Density is the overall darkness, or blackness, within a radiographic image
• Tissue density is the mass density of the radiographic subject
• mAs is primary controlling factor of radiographic density
• Radiographic contrast is the difference in density between any two adjacent portions of the image
• Kilovoltage is the primary controlling factor of contrast
• A short scale contrast exists if an image demonstrates only a few densities, and there is a great difference between the densities
• A low kVp setting produces an image with a short scale of contrast
• Higher kVp settings produce images with a long scale contrast
• High contrast is most desirable when differentiating tissues with similar tissue densities
• Fog is generalized unwanted exposure on the image
• Fog affects radiographic quality by causing decreased contrast
• Distortion is a variation in the size or shape of the image as compared with the subject it represents
• Magnification is another name for size distortion
• object-image receptor distance (OID) is the distance between the subject or part and the IR
• Penumbra is the unsharp, “fuzzy” appearance of margins of anatomic structures within the radiographic image
• Decreased resolution results from a change from the small focal spot to the large focal spot
• With a large OID, the reduction of excessive magnification is accomplished by increasing the SID
• Increased magnification results from an increase in OID
• Motion of the patient, the tube, or the IR during the exposure results in decreased resolution
• If the radiographic image appears blurred, spatial resolution is affected
• Decreasing exposure time is the principle means of controlling involuntary motion
• Quantum mottle, or graininess, in the radiographic image affects image quality by decreasing spatial resolution
• Quantum mottle occurs when the mAs or kVp is set too low
• Speaking with the patient regarding the process and what is needed is the 1st step in reducing motion
• Magnification decreases resolution
• The quantity of the exposure doubles if the mA doubles
• Contrast is the quality factor is key to the visibility of detail
• If the mA doubles, the dose to the patient will double
• kVp is the primary controlling factor of penetration of x-rays
• Brightness is the the term used in the digital imaging environment to replace density
• Scattered radiation contributes to fog
• Shape distortion is the result of unequal magnification of the actual shape of the structure
• Foreshortening occurs when a body part appears on a radiograph as shorter than it actually is
• Elongation occurs when a body part appears on a radiograph as longer than it actually is
• High contrast describes an image that demonstrates great differences between the densities

Chapter 8

• Computed radiography (CR) is a cassette-based digital imaging system
• The purpose of the photostimulable phosphor plate is to store the image of the body part until processed
• Indirect conversion of x-ray energy requires 2 steps in DR systems
• A PACS system is used to view and store digital x-ray images
• The front of the imaging plate is made of a radiolucent material that does not absorb x-rays
• Barium fluorohalide with europium is used as the phosphor that absorbs the x-ray energy in the imaging plate
• When a CR plate is inserted into the reader for processing, the phosphor is scanned with a laser beam
• The light in the flat panel detector is converted to an x-ray signal by the photodiode when using indirect conversion DR systems
• The ability to process images very fast is a main advantage of using CR and DR digital systems
• An exposure technique chart must be used with digital-based x-ray processors to ensure the ALARA concept is practiced
• Quantum mottle occurs in digital images if there are not enough photons reaching the IR
• A compensating filter should be used when imaging body parts that have extreme differences in tissue thickness
• When splitting a CR cassette in half for two exposures, the half not being exposed should be covered with lead
• When using digital systems, the part must be placed in the center of the plate or detector
• Storage phosphors in CR plates are hypersensitive to small levels of scatter radiation exposure
• A minimum of 2 sides of the collimated x-ray beam should be shown on the IR and image
• A grid is important to use when using digital systems for mobile radiography
• White light is used to erase the anatomical image after the phosphor is exposed and the imaging plate is scanned in the CR reader and the image is sent to storage
• A charge-coupled device (CCD) is used to convert light into an electric signal in an indirect conversion DR system
• A matrix is the viewing monitor's active viewing area
• A pixel is each square picture element in a digital viewing monitor is
• Spatial resolution is the amount of detail or sharpness in the digital image
• A 3,000 x 3,000 matrix will produce the best spatial resolution
• The greatest spatial resolution will be produced when the matrix is large and the pixels are small
• A matrix of 1,200 x 1,800 will show 2,160,000 pixels on the viewing monitor
• Contrast resolution is the ability to distinguish anatomical structures of similar subject contrast
• The number of gray shades that a digital system can reproduce is termed dynamic range
• The ability of the digital system to convert the x-ray input electric signal into a radiographic image is termed the signal-to-noise ratio (SNR)
• Quantum mottle describes Noise that refers to the amount of information that is not useful in the radiographic image
• The best quality radiographic image will be produced on the viewing monitor when there is high SNR and low noise
• Window level controls the density, or brightness, in the radiographic image
• Window width controls the contrast of the radiographic image
• Shuttering will blacken the clear or white areas around the collimation edges of a radiograph
• Image stitching a computer software function that allows separate radiographic images to be tied into one image for viewing
• Rand L markers should never be placed on the radiographic image using electronic means (computer software)
• Image annotation is the computer software function that allows any type of text to be written on a radiographic image
• Edge enhancement processing techniques can be used to increase contrast and sharpen the image
• Ensuring the kVp is set correctly is one of the most important aspects of setting the exposure factors when using digital systems is to
• Exposure indicator number tells the operator the correct exposure has been received by the phosphors in the imaging plate
• Post processing is the computer software function allows adjustment of the radiographic image after it has been processed
• DICOM is the universally accepted standard for exchanging radiographic images inside and outside the institution, and among all manufacturers
• DICOM gray-scale function is the calibration of an image display system that ensures that all radiographic images' gray scales are presented consistently
• Health level-7 ensures that all the different information systems within a given hospital or clinic can communicate effectively
• Quantum mottle is an artifact that can be identified in a radiographic image if there is inadequate exposure technique
• A Moiré pattern is an artifact that will occur when the grid lines are not aligned with the CR reader's laser light
• Light spots can be the appearance if there is foreign matter inside the CR imaging plate
• Phantom or ghost images can appear if the CR imaging plate is not erased properly
• Fogging occurs if the CR imaging plate receives too much background or scatter radiation
• Digital radiographic images are stored, retrieved, sent, and viewed using an extensive image management system called PACS
• A CR plate inside the cassette can be exposed to light after 15 seconds before it will start to erase

Chapter 9

• The patient is the primary source of interactions that produces scatter radiation
• Compton scatter occurs when an x-ray photon interacts with the outer orbital electron of an atom in the patient's body
• A scattered photon has less energy than the incoming primary beam photon
• Compton interactions occur at 40 to 125 kVp, the entire diagnostic range
• The photoelectric effect occurs when an incoming photon from the primary beam interacts with the inner shell electron of an atom in the patient's body
• Decreased contrast is how scatter radiation affects radiographic appearance
• As the size of the x-ray field increases, scatter radiation fog increases
• As the body part is thicker or larger, the amount scatter radiation fog increases
• If the kVp increases, scatter radiation fog increases
• Scatter radiation fog reduces the visibility of detail in a radiographic image by decreasing contrast
• The most effective and practical way to reduce scatter radiation fog on a radiograph is to use a grid
• A grid is placed between the patient and the IR to absorb scatter radiation
• Backscatter is Compton scatter that is directed from the patient back toward the x-ray tube
• A grid with a 12:1 ratio will require more exposure to make a satisfactory radiograph, compared to an 8:1 grid
• Grid frequency the number of lead strips per inch
• Cutoff is the radiographic appearance of decreased density on the lateral margins of the image is most likely caused by grid
• A grid should be employed when the part thickness is greater than 10cm
• Focused describes grids with lead strips that are aligned to coincide with the primary beam angle
• Grid cut off can be caused if a grid is misaligned with the central ray, causing a light area on the side of the image
• The grid oscillates to prevent the lead strips in the grid from being seen on a radiograph
• During the photoelectric effect, an incoming photon interacts with the atom in the patient's body and is totally absorbed by the atom
• Compton interactions will increase if the kVp is increased
• Photoelectric effect interaction will decrease f the kVp is increased
• A collimator template and beam alignment cylinder is used to check the collimator and beam alignment of the overhead tube crane
• When performing the beam alignment test, the x-ray tube must be within 1 degree(s) of perpendicular to be in control

Chatper 10

• Variable kVp and fixed kVp are technique charts.
• A technique chart is a listing of the various radiographic examinations performed in a radiographic room along with the exposure factors
• Technique charts are unique to each x-ray machine and each facility
• Technique charts are based on patient-body part measurements obtained using an x-ray caliper, which are expressed as part thickness in centimeters
• A radiographic phantom is a human skeleton or part of a skeleton encased in plastic to simulate human tissue
• The Joint Commission requires technique charts to be posted for every radiographic room
• Technique charts are based on the thickness of body part to be radiographed
• Variable kVp has a specific mAs value for each projection and uses small changes in kVp to compensate for variances in patient or part size
• Optimum kVp will provide the highest kVp setting, the lowest patient dose, and the greatest exposure latitude
• Using the principle of optimum kilovoltage to formulate exposure techniques minimizes patient exposure and wide exposure latitude
• An advantage of the variable kVp technique chart is the overall image contrast is lower, which can provide greater visibility of detail
• To determine if the mA station is obtainable at the desired kVp without exceeding the capacity of the x-ray tube, a tube rating chart should be consulted
• One reason for selecting the highest available mA station is to keep the exposure time as short as possible
• One reason for selecting a low mA station is to use the small focal spot
• The correct exposure time required to produce 50 mAs when using the 200 mA station is 0.25 seconds
• A kVp level not optimum to penetrate the part could be a cause of technique chart failure
• A change in mAs of 30% is needed if there is a 2-cm increase in part size
• If a satisfactory radiograph is made using 20 mAs at 40 inches SID and a similar radiograph at 60 inches SID is desired, 45 mAs is needed
• A radiograph would have too much contrast if the kVp level is set too low
• An increase in exposure technique would be required if a patient had cardiomegaly
• A decrease in exposure technique would be required if a patient had bowel obstruction
• When an image is too light, a 100% increase in mAs is the best technique adjustment for the repeat radiograph
• mAs should be used to correct problems with radiographic density
• kVp is used to alter radiographic contrast
• Contrast is primarily affected by kVp
• If the kVp is increased using the 15% rule, an 80 kVp exposure would change to 92 kVp
• The AP Thoracic Spine can benefit from the use of a compensating filter
• A Pediatric patient seldom requires a compensating filter for general radiographic examinations
• The minimum amount of mAs change that will prompt a visible change in image density is 30%
• A decrease in exposure technique would be required if a patient had degenerative arthritis
• Inadequate penetration of the body part is the major limitation in obtaining images of obese patients
• Increasing kVp is the single most important technical exposure adjustment that should be made when imaging an obese patient

Chapter 11

• The SI unit for measuring absorbed dose is the Gray
• The SI unit of exposure that measures radiation in air is the Air kerma
• The unit of the Sl system used to measure equivalent dose is the Sievert
• The unit commonly used to report the effective dose to occupational workers in the United States is mSv (old mrem)
• Cumulative effective dose ensures lifetime risk of occupationally exposed persons remains within acceptable limits
• Equivalent dose is measured based on the type and energy of the radiation one is exposed to
• The radiation weighting factor for x-ray photons is 1
• In radiography, patient dose is usually calculated at the skin level
• Pelvis radiographic examinations typically delivers the greatest gonadal exposure
• Blood and blood producing cells are very radiosensitive, according to the Law of Bergonie and Tribondeau
• Patient doses in radiography are usually calculated as the Entrance skin exposure (ESE)
• Blood changes will be seen at a whole body equivalent dose of 0.25 Sv
• Nerve cells are not as vulnerable to x-rays
• Death will occur at a whole-body equivalent dose of 6.0 Sv
• Short-term effects of radiation would occur within 3 months
• Adults are the least sensitive to radiation according to the Law of Bergonie and Tribondeau
• Erythema is the reddening of the skin
• ALARA (as low as reasonably achievable) is the guiding philosophy of radiation protection
• The EDE limit for whole body dose of occupational radiation exposure for non-pregnant workers older than age 18 who are involved in radiation use is 5.0 rem per year
• Gonad shields would be used to reduce the likelihood of genetic radiation effects
• Erythema is a common observable short-term effect of radiation is
• The lethal dose of radiation is expressed as the LD 50/30
• A Lumbar spine radiographic examinations would give the fetus the highest fetal dose
• The greatest percentage of long-term effects from radiation exposure will occur at 10 to 15 years
• Erythema is a short-term effect of radiation exposure
• Short term effects of radiation exposure are predictable
• Radiation exposure to the gonads can cause mutations in the genes of the irradiated person
• Leukemia would not be a mutation as a result of radiation to the gonads
• The average American of today is exposed to 6.3 mSv of annual radiation
• Repeat exposures are the greatest cause of unnecessary radiation to patients
• The lead-equivalent thickness of a gonad shield should be 0.5 mm
• A gonad shield should be used whenever the edge of the radiation field is within 5 cm of the gonads
• The federal regulation for the lead-equivalency of aprons that are worn in the radiographic room is 0.5 mm
• The federal regulation for the lead-equivalency of gloves worn during radiographic procedures is 0.25 mm
• Personnel monitors should be worn whenever radiation workers are likely to risk receiving 10% or more of the annual effective dose limit
• Optically stimulated luminescence (OSL) is the most widely used and most accurate personnel monitor
• A personnel monitor cannot measure exposure less than 0.05 mSv
• Personnel monitors should be worn on the collar outside the apron
• The National Council on Radiation Protection (NCRP) prepares the standards for radiation dose limits of occupational radiation workers
• The annual effective dose limit for an occupational radiation worker is 50 mSv
• A 28 year-old radiation worker can have an annual cumulative effective dose of 280 mSv
• The greatest risk for a pregnant woman who receives a high exposure is during the first trimester
• The NCRP recommended monthly equivalent dose limit for a pregnant worker is 0.5 mSv
• The NCRP recommended 9-month equivalent dose limit for a pregnant worker is 5 mSv
• A declared pregnant radiation worker should wear a second personnel monitor at the waist level

Chapter 12

• Connective tissue is the most widely distributed with the greatest variety of form and function
• The Alimentary canal may be used in place of the gastrointestinal tract
• The two basic divisions of the skeletal system are the axial and appendicular
• Flat bones made up of two layers of compact bone with a thin cancellous layer between them?
• A Condyle is a rounded process that forms a part of a joint
• A Styloid a long, sharp bony process
• Foramen is a hole in bone that provides a passage for nerves and blood vessels
• Synarthrosis are joints that are not moveable
• A joint that is classified as diarthrodial is freely moveable
• Abduction is the movement of a part away from the central axis of the body
• Extension is used to describe a straightened joint
• Supination means to turn the arm so that the palm of the hand is up
• Anatomical position includes standing facing the observer with palms of hands turned forward and toes facing anteriorly
• Cephalad means toward the head
• Posterior is the back portion of the body or part
• The Midsagittal plane divides the body into equal right and left halves
• The midcoronal plane divides the body into equal anterior and posterior halves
• The Supine body position term indicates that the patient is lying on his or her back
• When a patient is imaged in the prone position, the patient must be placed in recumbent position on his or her stomach
• Decubitus radiographic position requires a recumbent body position and a horizontal CR
• Projection describes the path of the CR from the radiographic tube through the patient, and to the IR
• An axial projection is achieved when the CR is angled longitudinally more than 10 degrees
• The x-ray tube, the IR, and the body part must be precisely aligned
• The side of the patient is indicated by a side marker
• Blurring of the radiograph results from imaging patient motion on a radiograph
• Lesion is a localized area of destructive change in body tissue
• Symptom is used to describe the patient's report of his or her perception of the condition
• Acute diseases are characterized by a sudden onset of symptoms and/or signs
• latrogenic diseases that occur as a result of treatment by health professionals are termed
• Edema is the proper medical term for swelling?

Chapter 13

• Phalanges are the bones that comprise the digits of the hands
• Metacarpals are the bones located in the palm of the hand
• Scaphoid is the carpal bone located in the proximal row on the lateral side
• Trapezium is the carpal bone that articulates with the first metacarpal
• Ulna is the bone of the forearm located on the medial side
• The radial tuberosity is located at the proximal end, distal to the head of the radius
• The olecranon process is located at the proximal end of ulna
• The styloid process is located at the distal end of the radius
• Capitulum is the portion of the humerus that articulates with the radial head
• Acromion is the name of the large, rounded projection that can be felt on the superior, lateral surface of the shoulder
• The anterior (palmar) surface of the hand should be in contact with the IR for the PA projection
• The Third MCP joint is where the CR is directed for the PA projection of the hand
• Using a stair-step sponge to support the fingers helps demonstrate the interphalangeal joints on the PA oblique projection of the hand
• When radiographing the fingers, include the distal portion of the metacarpals and all of the phalanges
• The Medial surface of the hand should be in contact with the IR for a lateral projection of the fifth digit
• The proximal interphalangeal joint is where the CR is directed for a PA projection of the second digit
• MCP joint is where the CR is directed for the AP projection of the thumb
• Oblique is the position of the thumb on a PA projection of the hand
• The PA projection of the thumb results in a more magnified image because of the increase in OID
• Flexing the fingers into a loose fist places the wrist in closer contact with the IR for the PA projection of the wrist
• The coronal plane of wrist is at a 45-degree angle to the IR with anteromedial surface on IR for the PA oblique projection with lateral rotation
• The Lunate and pisiform carpal bones are best demonstrated on the AP oblique projection of the wrist in medial rotation
• In radiography of the forearm, it is important to include both bones in their entirety and their articulations
• Elbow extended, wrist and elbow parallel to IR, hand supinated is the proper patient position for the AP projection of the forearm
• The Medial surface of the forearm is in contact with the IR when radiographing the forearm in a lateral position
• An AP projection of the proximal forearm, an AP projection of the distal humerus, and an AP oblique projection in lateral rotation can be substituted for a routine AP projection of the elbow joint when the patient is unable to extend the elbow
• The AP oblique projection; demonstrates the radial head and capitulum without superimposition in 45-degree lateral rotation position
• The coronoid process of the ulna and the trochlea are elbow anatomy that is best demonstrated on the AP oblique projection in 45-degree medial rotation
• The upper limb is abducted, elbow extended, and the humeral epicondyles parallel to IR describes the proper method to position the humerus for an AP projection
• For the lateral projection of the humerus, the proper relationship of the humeral epicondyles with the IR is perpendicular
• For the AP projection of the shoulder direct the CR 1 inch medial and inferior to coracoid process
• AP projection; external rotation of the shoulder demonstrates the greater tubercle of the humerus in profile
• The lesser tubercle of the humerus