Mock registry

Arrange the following answers in order, beginning with the most appropriate course of action and ending with the least. Your patient speaks very little English, seems to understand some, but is not able to answer the questions you ask while trying to obtain her medical history. She is accompanied by her daughter, who is about ten, and speaks English well. - Ask the daughter to translate for her mother -Speak loudly and slowly so that the patient can understand more of what you are saying -Reschedule for a time the patient can return with a family translator who is over 18 -Reschedule in order to have a medical interpreter present

1. Reschedule in order to have a medical interpreter present 2. Reschedule for a time the patient can return with a family translator who is over 18 3. Speak loudly and slowly so that the patient can understand more of what you are saying 4. Ask the daughter to translate for her mother Federal law guarantees the patient the right to effective communication in the medical setting, regardless of that person's ability to speak English. The medical history should always be taken in a language that the patient can understand and speak. A person trained in medical interpretation is the best choice for interpretation, eliminating the communication barriers that can occur when a family member is asked to translate. A minor child should never serve as a translator

The lateromedial lateral projection of the elbow requires that the 1. humeral epicondyles are parallel to the CR 2. humeral epicondyles are parallel to the IR 3. humeral epicondyles are perpendicular to the CR A. 1 only B. 1 and 2 only C. 2 and 3 only D. 1, 2, and 3

A. 1 only (A) The lateromedial lateral projection of the elbow requires that the elbow be flexed 90° with the medial aspect of the humerus and forearm in contact with the IR. The humeral epicondyles should be superimposed, perpendicular to the IR, and parallel with the CR.

A megabyte is equal to: A. 1,000,000 bytes B. 1,000 bytes C. 1,000,000,000 bytes D. 1,000,000,000,000 bytes

A. 1,000,000 bytes Mega- is a prefix meaning one million. Therefore, one megabyte is one million bytes. One byte is equal to 8 bits (A). One thousand bytes would be indicated as one kilobyte (B). One billion bytes would be indicated as one billion bytes (C). One thousand billion byes would be indicated as one terabyte (D).

Which of the following needle sizes has the largest bore? A. 18-gauge B. 20 -gauge C. 22-gauge D. 26-gauge

A. 18-gauge Gauge is used to describe the size of a needle, and is a measurement of the bore, or opening of the inside of the needle. The largest bores are the lowest numbers, so an 18-gauge needle is larger than a 26-gauge.

What is the NCRP recommended minimum total filtration for x-ray equipment operating above 70 kV p? A. 2.5 -mm aluminum equivalent B. 1.5 - mm aluminum equivalent C. 0.5 - mm aluminum equivalent D. 2.0 - mm aluminum equivalent

A. 2.5 -mm aluminum equivalent Total filtration of 2.5 - mm aluminum equivalent for fixed x-ray units operating above 70 kVp is the regulatory standard (A). A 1.5 - mm aluminum equivalent is the required filtration for 50-70 kVp (B). A 0.5 - mm aluminum equivalent is the required filtration for any kVp below 50 (C).

The NCRP recommends that the annual occupational exposure to the hands, feet, and skin not exceed A. 500 mSv B. 150 mSv C. 100 mSv D. 50 mSv

A. 500 mSv The National Council on Radiation Protection and Measurements publishes a summary of dose limit recommendations. The annual occupational exposure must not exceed 50 mSv; the cumulative effective dose limit must not exceed 10 mSv times X age in years. The lens of the eye is its most radiosensitive structure and its annual dose limit is 150 mSv. The dose limit to localized, less radiosensitive tissues such as the hands, skin, and feet is 500 mSv.

The purpose of the amorphous silicon photodiode in an indirect capture digital radiography system is to A. Allow the current produced to flow in only one direction B. Redirect light produced to a photomultiplier tube C. Convert x-ray energy to light energy D. Determine the histogram appropriate for the anatomical part being examined

A. Allow the current produced to flow in only one direction The amorphous silicon photodiode is used in indirect capture digital systems. This diode, acting like an electrical switch, only allows electrical charges to be delivered in one direction toward the image processor, which converts this energy into a digital image (A). Light collection optics direct the release phosphor light energy from the CR IP to an optical filter and then to the photomultiplier (photodetector) tube in the CR scanner (B). A scintillator converts X-ray energy to light energy. Materials used as scintillators in a digital system include cesium iodide (CsI) or gadolinium oxysulfide (Gd2O2S), which are used in another type of indirect capture digital system (C). The digital data contained within a collimated region of an exposed body part produces a graphical representation of the optimal brightness values displaying the anatomical part is called a histogram (D).

Which of the following environmental factors can reduce optimal image contrast while viewing an anatomical image on a monitor? A. Ambient light B. Pixel pitch C. Scatter radiation D. Room temperature

A. Ambient light Ambient light can reduce the image contrast while viewing an image on a monitor. For this reason, active matrix liquid crystal displays are designed to reduce the influence of ambient light on image contrast (A). The pixel pitch relates to the distance between the center of one pixel to the center of an adjacent pixel in an image matrix, which is a physical characteristic of the digital detector system that cannot be changed. Smaller pixel pitch provides increased spatial resolution (B). Scatter radiation occurs in the patient through Compton interaction between the x-rays and tissues within the body, which can reduce image contrast via image fog. Scatter radiation cannot reduce image contrast on an image that has already been processed and displayed (C). Room temperature does not interfere with viewing of the monitor image (D)

Which of the following devices allow for the limitation of the beam to the area of clinical interest? A. Collimator B. Grid C. Lead shields D. Compensating Filter

A. Collimator The collimator is the most commonly employed beam restrictor in radiography. The collimator allows the technologist to set an infinite number of field sizes and aid in properly placing the tube and central ray (A). Grids are placed between the patient and the image receptor to absorb scatter radiation (B). Lead shields are made of various sizes of lead-impregnated vinyl and are typically used to shield the gonads (C). Compensating filters are usually employed to solve a problem with unequal subject densities. The goal is to add an absorber to compensate for unequal absorption within the subject (D).

Image quantum noise is caused by A. Deficient mAs B. Scattered photons C. Excessive edge enhancement D. Small metallic objects in the anatomical part being radiographed

A. Deficient mAs Quantum noise is seen as brightness fluctuations on the image, with a mottled, or speckled, appearance. This is caused by a deficiency in the number of x-ray photons (deficient mAs) used to create the image. This can be eliminated by using the appropriate mAs setting for the anatomical part being radiographed (A). Scattered radiation produces a blanket of fog (gray or medium brightness values) on the digital image, decreasing the visibility of anatomical structures. Through the use of proper collimation, radiographic grids, and proper technical factors, scatter fog can be reduced (B). Excessive edge enhancement can cause a halo artifact, whereby anatomical information may be eliminated. This is particularly a problem when radiographing a hip prosthesis, where the halo artifact may create the appearance that the prosthesis is loose (C). Metallic objects within the anatomical part being radiographed will appear as increased brightness, as they absorb x-ray photons by way of photoelectric interactions (D).

Identify the 4 objective/physical signs below A. Diaphoresis B. Febrile C. Pain level described by patient D. Blood pressure E. Rapid pulse F. Patient description of anxiety

A. Diaphoresis B. Febrile D. Blood pressure E. Rapid pulse he radiographer should be alert to the patient's appearance and condition, and any subsequent changes in them. These are often referred to as objective signs. It is important to notice the color, temperature, and moistness of the patient's skin. Paleness frequently indicates weakness; the diaphoretic patient has pale, cool skin. The febrile patient is usually exhibits hot, dry skin. "Sweaty" palms may indicate anxiety. A patient who becomes cyanotic (bluish lips, mucous membranes, or nail beds) needs oxygen and requires immediate medical attention. Vital signs (temperature, blood pressure, respirations, pulse) are observable and measurable objective signs that can provide crucial information about an individual's state of health. The Subjective signs are those perceived by the patient—how he or she feels, what is the level of his or her pain, and so on. Subjective information can be just as valuable as objective information, and the radiographer's listening skills can have a great deal to do with the patient's lasting impression of his or her health care experience

Which of the following would be considered a potential disadvantage of CR vs. conventional/analog radiography? A. Dose creep B. Increased spatial resolution C. Decreased IP fogging due to background radiation D. Increased latitude

A. Dose creep The term dose creep refers to the tendency of a radiographer to increase the amount of exposure to the patient and image receptor to avoid quantum mottle noise and reliance on automatic rescaling. Automatic rescaling is a digital system function whereby the images are produced with uniform brightness and contrast, regardless of the amount of exposure. Rescaling should not be used as a substitute for appropriate technical factors, in support of the ALARA principle. Reliance on automatic rescaling without regard to the appropriate exposure factors for a given patient is an unethical practice (A). The number of pixels within a matrix determines the spatial resolution. A larger number of pixels within a matrix equates to smaller individual pixel sizes. Smaller pixels therefore have a smaller pixel pitch, which is the distance from the center of a pixel to an adjacent pixel. Smaller pixel pitch provides increased spatial resolution (B). CR image plates are very sensitive to background radiation, which fogs the IP. For this reason, it is important to erase the IPs prior to using them for radiographic procedures (C). An advantage of CR over conventional radiography is the increased latitude, which means that a much larger error of exposure can be tolerated to produce a diagnostic image (D).

Post-processing a digital radiographic image using electronic masking would result in which of the following? A. Enhanced visualization of the edges of the anatomical structures B. Magnification of the radiographic image C. Radiation dosage to the patient D. Improved spatial resolution

A. Enhanced visualization of the edges of the anatomical structures Electronic (unsharp, or blurred) masking is a post-processing function that improves the visualization of the edges of an anatomical part. By using the blurred image produced from a low-pass filtering process and subtracting it from the original image, the edges of the anatomical part become sharper (A). Magnification mode is a post-processing function that increases the image size, but does not accentuate the edges of an anatomical part (B). Radiation dosage to the patient occurs during the radiographic exposure. This cannot be changed with any post-processing methods (C). Spatial resolution is inherent to the matrix size and cannot be changed (D).

Select the 5 correct examples of non-verbal communication A. Eye contact B. Using non-medical terminology C. Orderly work area D. Smile E. Gentle touch F. Speaking in a moderate tone G. Neat personal appearance

A. Eye contact C. Orderly work area D. Smile E. Gentle touch G. Neat personal appearance Nonverbal communication involves facial expression, touch, eye contact, professional appearance, orderliness of the radiographic department and work area, preparation and efficiency of the radiographer, and other body language Verbal communication involves the tone and rate of speech, as well as what is being said. It involves personalization and respect.

The area of anatomical information displayed in a matrix is determined by the A. Field of view B. Pixel size C. Dynamic range D. The number of bits in each pixel

A. Field of view When imaging a patient using digital imaging, the radiographer selects the matrix size for the examination, referred to as the field of view (FOV). In this case, the dimension of the matrix size is used to represent the FOV and is the dimension of the anatomical part being radiographed (A). Pixel size determines the spatial resolution in a matrix (B). The dynamic range is determined by the pixel depth, which determines the contrast resolution in the digital image. For example, if a pixel has a bit depth of 8, then the number of gray tones the pixel can display is 2 to the power of the bit depth, or 256 shades of gray (C). The number of bits in each pixel is called the bit depth. Bit depth determines the number of shades of gray that can be displayed by each pixel, which, in turn, determines contrast resolution in the digital image (D).

The following symptoms are characteristic of what type of seizure? Symptoms: rigid muscles and arching of back, jerky and irregular body movements, possible vomiting, froth or blood streaked saliva from the mouth, urinary or fecal incontinence. A. Generalized B. Complex partial C. Simple partial D. Syncope

A. Generalized The generalized, grand mal, or tonic-clonic seizure is the most severe and the patient usually falls into a deep sleep following it. The complex partial seizure may demonstrate as facial grimacing, emotional outbursts, and confusion and lack of memory following the seizure. A simple partial seizure may be localized to only tremors in one small area of the body. The patient may have sensory illusions of tastes, smell, or sound. He or she will not lose consciousness. Syncope is fainting

A larger number of pixels in the digital matrix image produces A. Increased spatial resolution B. Decreased spatial resolution C. Increased contrast D. Increased image brightness

A. Increased spatial resolution A larger number of pixels within a matrix equates to smaller individual pixel sizes. Smaller pixels therefore have a smaller pixel pitch, which is the distance from the center of a pixel to an adjacent pixel. Smaller pixel pitch provides increased spatial resolution (A). A larger number of pixels within a matrix would increase, not decrease spatial resolution (B). The image contrast is determined by the pixel depth, or dynamic range, of the pixels, which determines contrast resolution (C). Image brightness is determined by the exposure intensity and this brightness can be adjusted using window leveling during post-processing. The brightness level has no effect on the spatial resolution (D).

If a disease-causing microorganism is transmitted from one patient to another by means of an improperly cleaned instrument, the means of transmission is: A. Indirect contact B. Direct contact C. Vehicle D. Vector E. Droplet contact

A. Indirect contact Indirect contact is a two-step process, where an infected person touches an object, such as a doorknob, telephone, or surgical instrument, and then another person touches the same object while pathogenic microorganisms are still living on the surface. The object is called a fomite.

The number of ionizations occurring along the path of the x-ray photons refers to A. LET B. RBE C. LNT D. ALARA

A. LET (A) LET refers to Linear Energy Transfer. Diagnostic x-ray is described as low LET radiation. This means that the number of ionizations occurring along the path of the x-ray photons is fewer than with other types of ionizing radiations like alpha and beta particles. Alpha particles ionize immediately while beta particles ionize as they penetrate only a few millimeters of tissue. X-ray photons are more penetrating and therefore have less opportunity for multiple ionizations. RBE refers to Relative Biological Effectiveness, LNT refers to Linear Non-Threshold, and ALARA refers to As Low As reasonably Achievable.

Which of the following would be considered a disadvantage of an indirect capture digital system compared to a direct capture digital system? A. Lower MTF B. Higher MTF C. Smaller number of detectors D. Limited field size

A. Lower MTF Modulation transfer function, or MTF, is a ratio of the image to the object being radiographed and determines the ability of the digital system to record spatial frequencies. In an indirect capture system where x-ray photon energy is converted to light in the phosphor/scintillation layer, there will always be spreading out of the light, which reduces system efficiency; the more light spread there is, the less the image looks like the anatomical object and therefore, the lower the MTF will be (A). Higher MTF is obtained with direct capture digital systems, as the x-ray energy is converted directly to an electrical signal (B). The number of detectors is determined by the manufacturer in both indirect and direct capture digital systems (C). The field size can be the same for both indirect and direct capture systems, which depends on the manufacturer and the field of view controlled by the radiographer (D).

Which of the following cell types is related to bone building and calcification? A. Osteoblasts B. Chondroblasts C. Osteocytes D. Osteoclasts

A. Osteoblasts (A) Osteoblasts build bony matrix and initiate calcification. Osteoblasts do not undergo cell division but surround themselves with matrix and become osteocytes. Osteocytes do not undergo cell division, are mature bone cells, and maintain bone tissue metabolism by exchanging nutrients and wastes with the blood. Chondroblasts undergo cell division and are immature bone cells of cartilage tissue. Osteoclasts are large, multinuclear cells that reabsorb bone matrix.

The layer of a PSP that is responsible for trapping electrons in F-centers during an exposure is called the A. Phosphor layer B. Protective layer C. Reflective layer D. Backing layer

A. Phosphor layer The phosphor layer in a PSP is a layer of photostimulable phosphor that "traps" electrons during an x-ray exposure. It is usually contains barium flourohalide phosphors. This layer also contains a dye that absorbs the stimulating light to prevent spreading of the light produced. When x-rays expose the IP, the europium atoms also contained within the phosphor are ionized and the electrons from these atoms move from a valence band (ground state0 to a conduction band (higher energy level). The electrons in the conduction band are now free to travel to the so-called "F-centers." The "F" comes from the German word "Farbe", meaning color. The number of trapped electrons is proportional to the x-ray energy absorbed. It is at the point in this process that the electrons are spatially distributed to create the latent image (A). The protective layer is a very thin layer, which consists of clear plastic, and serves to protect the phosphor layer (B). The reflective layer reflects light from the phosphor layer in a forward direction when scanned by the CR scanner (reader) (C). The backing layer is a soft polymer and serves to protect the back of the CR Image plate (D).

Which of the following is a formula to determine pixel size? A. Pixel size = FOV/matrix size B. Pixel size = ½ x sampling frequency C. Pixel size = matrix size/bit depth D. Pixel size = pixel pitch/2

A. Pixel size = FOV/matrix size The pixel size of a matrix can be calculated using the following relationship: Pixel size = FOV/Matrix Size (A). The remaining answers are incorrect (B,C, D).

Select the three correct statements from those listed below A. Potential biologic effects increase as LET increases B. Double strand DNA breaks occur with low LET radiation C. The presence of oxygen increases tissue radiosensitivity D. The direct effect is associated with formation of free radicals E. Point mutations are not repairable F. RBE increases as LET increases

A. Potential biologic effects increase as LET increases C. The presence of oxygen increases tissue radiosensitivity F. RBE increases as LET increases The target theory specifies that DNA is the key sensitive molecule and photon damage can cause impaired function or cell death. Because 65%-80% of the body is composed of water, most interactions between ionizing radiation and body cells will involve radiolysis of water rather than direct interaction with DNA. The two major types of effects are the direct effect and the indirect effect. The direct effect occurs when the ionization occurs directly with the key molecule (DNA). Chemical damage can occur as chemical bonds are broken and the chemical structure is changed. This can result in impaired function or cell death. Direct effect usually occurs with high-LET radiations (e.g., alpha particles and neutrons) and when ionization occurs at the DNA molecule itself. The more frequently occurring indirect effect happens when ionization occurs away from the DNA molecule, in cellular water. Ionization of water molecules (radiolysis) produces one or more atoms having unpaired electrons (free radicals). A free radical is very short lived but highly reactive; it can break chemical bonds in an effort to pair with another electron, and can even travel a considerable distance from its source. The indirect effect is predominant with low-LET radiations such as x-rays. RBE (Relative Biologic Effect) increases as LET increases. Oxygenated tissues are more sensitive to low LET radiation exposure than hypoxic or anoxic tissues

You and one assistant receive an average size female patient on a gurney with possible spinal injury. You must transfer her to the exam table to complete her imaging exams. Which would be the best choice of transfer methods in this situation? A. Sliding or "smoothie" board B. Log roll method C. Sheet transfer D. Allow the patient to move herself if she is able

A. Sliding or "smoothie" board A patient with possible spinal injury should always be kept anatomical alignment to prevent further injury. Adequate personnel should always facilitate the transfer to prevent patient and health care worker injury. The sliding board ("smooth mover") bridges between the gurney and the table, allowing for safe transfer with fewer personnel. The log roll method requires one person to hold the patient's head and two, at minimum, to support the chest, abdomen, and limbs. The sheet transfer method requires also requires one person to support the patient's head, and one person on each side

Select the 3 correct statements regarding the Bucky slot cover A. The Bucky slot cover is a hinged metal arm attached to the Bucky tray B. The Bucky slot cover is in place when the Bucky tray is positioned at the foot of the x-ray table C. The Bucky slot cover must have at least 0.5 mm Pb equiv D. The Bucky slot cover reduces occupational gonadal dose E. The Bucky slot cover increases patient dose

A. The Bucky slot cover is a hinged metal arm attached to the Bucky tray B. The Bucky slot cover is in place when the Bucky tray is positioned at the foot of the x-ray table D. The Bucky slot cover reduces occupational gonadal dose The Bucky slot cover is a hinged metal arm attached to the Bucky tray that slides into place when the Bucky tray is positioned at the foot of the x-ray table. It is at the approximate level of the gonads and therefore reduces gonadal dose to the fluoroscopist and radiographer. The Bucky slot cover must have at least 0.25 mm lead equivalent. The Bucky slot cover it Is unrelated to patient dose

Which three statements are true regarding the lateral projection of the lumbar spine? A. The MSP is parallel to the tabletop. B. The pedicles are well visualized. C. Vertebral foramina are well visualized. D. The midcoronal plane is aligned with the midline of the grid E. Zygapophyseal articulations nearest the IR are well demonstrated F. The CR is usually angled 5-8° cephalad if the spine cannot be adjusted horizontally

A. The MSP is parallel to the tabletop. B. The pedicles are well visualized. D. The midcoronal plane is aligned with the midline of the grid A, B, D) With the patient in the lateral position, the MSP is parallel to the x-ray tabletop and the coronal plane is aligned with the midline of the grid. Because the intervertebral foramina, which are formed by the pedicles, are 90 degrees to the MSP, they are well demonstrated in the lateral projection. The intervertebral joints (i.e., disk spaces) are also well demonstrated. The spinal cord passes through the vertebral foramina, which would not be visualized in conventional radiography of the lumbar spine. Zygapophyseal articulations are demonstrated in the oblique projections. If a radiolucent support cannot be placed under the lower thorax to place the long axis of the spine horizontally, the CR is directed 5 to 8° caudad.

Select the three correct statements regarding the x-ray tube anode A. an induction motor rotates the anode B. the anode is the negative electrode C. the two parts of an induction motor are its stator and rotor D. the anode rotates about 3600 RPM E. the anode is heated by 3-5 A into 10-12 V F. molybdenum is added to the focal track to help prevent pitting

A. an induction motor rotates the anode C. the two parts of an induction motor are its stator and rotor D. the anode rotates about 3600 RPM The x-ray tube is a diode - it has two electrodes; the anode is the positive electrode and the cathode is the negative electrode. The anode is made to rotate through the use of an induction motor. An induction motor has two main parts, a stator and a rotor. The stator is the part located outside the glass envelope and consists of a series of electromagnets occupying positions around the stem of the anode. The stator's electromagnets are supplied with current, and the associated magnetic fields function to exert a pull on the rotor within. Anode rotation is typically about 3600 RPM. The filament is heated with 3-5 A and 10-12 V by the filament circuit in order to produce thermionic emission. The filament current is kept at a standby quantity until the rotor is activated.

Select the three essential requirements for x-ray production from those listed below A. thermionic emission B. solid state rectifiers C. electron acceleration D. induction motor E. high-speed rotation F. electron deceleration G. source of direct-current

A. thermionic emission C. electron acceleration F. electron deceleration (A,C,F) Diagnostic x-rays are produced within the x-ray tube when high-speed electrons are rapidly decelerated upon encountering the tungsten atoms of the anode. The source of free electrons is the heated cathode filament producing thermionic emission. The electrons are focused by the nickel focusing cup and are driven across to the anode focal spot when thousands of volts are applied. When the high-speed electrons are suddenly stopped at the focal spot, their kinetic energy is converted to x-ray photon energy in one of two ways; Bremsstrahlung (Brems or "braking") radiation and Characteristic radiation. Brems radiation comprises 70%-90% of the x-ray beam. Less than 1% of the kinetic energy is converted to x-rays; the remainder is heat production.

The bones that articulate with the occipital bone include 1. Temporal bones 2. Parietal bones 3. Ethmoid bone A. 1 only B. 1 and 2 only C. 2 and 3 only D. 1, 2, and 3

B. 1 and 2 only (B) The eight cranial bones articulate via sutures which are synarthrotic (immovable) joints. The occipital bone forms part of the posterior and inferior part of the cranium. Its upper portion on each side articulates with parietal bones to form the lambdoidal suture. Its basilar portion articulates anteriorly with the sphenoid bone's clivus. The inferolateral portions of the occipital bone articulate with each temporal bone. Its foramen magnum is the large opening transmitting the inferior portion of the brain and continuous with the spinal cord. The squamosal portion of the occipital bone is posterior and superior, presenting the external occipital protuberance.

The thoracic spine articulates with the ribs at the 1. Costovertebral articulation 2. Costotransverse articulation 3. Vertebrosternal articulation A. 1 only B. 1 and 2 only C. 2 and 3 only D. 1, 2, and 3

B. 1 and 2 only (B) There are 12 thoracic vertebrae, which increase in size as they progress inferiorly toward the lumbar region. Thoracic spinous processes are fairly long and are sharply angled caudally. The thoracic vertebrae have facets for articulation with ribs. These structures form the costovertebral (head of the rib with vertebral body) and costotransverse (tubercle of the rib with the transverse process of vertebra) articulations. The costochondral articulation describes where the anterior end of the rib articulates with its costal cartilage. Ribs 1 to 7 articulate with the thoracic vertebrae and sternum and are called vertebrosternal or "true" ribs. Ribs 8 to 10 articulate with the thoracic vertebrae and the superjacent costal cartilage to form the anterior costal margin and are called vertebrochondral or "false" ribs. The last two pair of false ribs articulate only with thoracic vertebrae and are referred to as "floating "ribs.

Advantages of fewer fluoroscopic pulse/second sequences include 1. Less image noise 2. Lower patient dose 3. Less x-ray tube wear and tear 4. Greater temporal resolution A. 1 and 2 only B. 2 and 3 only C. 1, 2, and 3 only D. 1, 3, and 4 only

B. 2 and 3 only Pulsed fluoroscopy can be manual (also called intermittent) or automatic. Because exposure is interrupted, rather than continuous, patient dose is significantly decreased. Exposure occurs in pulses, so the fewer the pulses the less the patient exposure. Interrupted exposure has the added benefit of building up fewer heating units, thereby increasing x-ray tube life. Common pulse rates are 7.5, 15, and 30 pulses per second. A greater number of pulses per second are used to achieve temporal resolution, as in vascular procedures to record a rapid motion. Each pulse of radiation is usually less than 10 ms. Shorter pulse length (less than 10 ms) improves resolution but decreases the SNR because fewer x-ray photons are used.

How far can pathogenic organisms that are transmitted by droplet travel? A. 2 feet B. 3 feet C. 5 feet D. 10 feet

B. 3 feet Infection spread by droplet occurs when an infected individual expels small droplets of saliva, mucus, or any other body fluid via a sneeze, cough, when talking, etc. The droplet usually cannot travel more than 3 feet. Influenza, rubella, and diphtheria are some examples of infections that are transmitted via droplet.

In CR, the latent image is considered a(n) A. Digital image B. Analog image C. Manifest image D. Post-processed image

B. Analog image When remnant X-rays strike the PSP IP, a latent image is stored as energy within the IP. This stored energy, once scanned by a red laser beam such as a helium-neon beam, is released as light and it is this light that is subsequently captured to create the CR manifest image (B). In CR, the digital image is produced by releasing stored energy in the IP as light and translating the analog signal this light produces into binary code, or the digital image (A). A manifest image is one that demonstrates anatomical structures with particular spatial and contrast resolution, and a range of brightness levels (C). A post-processed manifest digital image is electronically manipulated to create an optimal image within the limits of the system, and technical factors and positioning accuracy used when the procedure was performed (D).

Select the three phrases below that are associated with deterministic effects: A. Have no threshold dose B. Are predictable C. Proportional to dose received D. Characterized by linear dose responses E. Increasing in number past two decades

B. Are predictable C. Proportional to dose received E. Increasing in number past two decades (B, C, E) Risks associated with exposure to ionizing radiation can be divided into two categories: deterministic/nonstochastic and probabilistic/stochastic. Deterministic risks are characterized by nonlinear dose responses and are associated with a threshold (safe) dose below which no effect is observed, making them predictable. Deterministic effects are believed to result from radiation-induced death of large groups of tissue cells, resulting in serious functional impairment. The severity of any injury increases with increasing ionizing radiation dose, making them predictable and measurable. Examples include radiation-induced skin injury, hypothyroidism, cataract formation, hair loss, temporary infertility, and sterility. Deterministic effects are referred to as "early effects" because they generally arise within days or weeks after exposure, although some of the induced skin injuries, cataracts, and hypothyroidism have long latency periods. Unfortunately, with the huge increase in high dose interventional procedures such as cardiac catheterizations, the past two decades has seen a considerable increase in deterministic effects such has not been seen since the early days of x-ray. Stochastic effects include heritable genetic effects and some somatic effects. They are the foremost late effects that are expected to occur in populations exposed to ionizing radiation; somatic effects (i.e., radiation- induced cancer) are the leading health detriment. With stochastic effects, the probability of their occurrence—but not their severity—is dependent on the radiation dose. However, for most stochastic effects, it is generally accepted that there is no threshold, that is, no safe dose. Radiation-induced cancers and genetic effects cannot be distinguished from those that appear spontaneously.

The higher the sampling frequency and the smaller the pixel pitch, the A. Better the contrast resolution B. Better the spatial resolution C. Less detective quantum efficiency present D. Less the patient exposure

B. Better the spatial resolution A larger number of pixels within a matrix equates to smaller individual pixel sizes. Smaller pixels therefore have a smaller pixel pitch, which is the distance from the center of a pixel to an adjacent pixel. Smaller pixel pitch provides increased spatial resolution. Pixel sampling can be described as sampling frequency, which is the frequency at which a data sample is acquired form the detector and is expressed as sampling pitch. Sampling pitch describes how digital detectors sample the received X-ray exposure. In CR, the sampling pitch is the distance between the laser beam positions during scanning of the IP, and for digital systems it is the distance between detector elements (DEL) (B). The image contrast is determined by the pixel depth, or dynamic range, of the pixels, which determines contrast resolution. A larger number of pixels within a matrix would increase. (A). Detective quantum efficiency (DQE) is a measure of the efficiency and fidelity with which the IR can convert X-rays received (incident quanta) into a useful digital image (C). Once the patient has been exposed, the dosage to the patient cannot be altered. The digital system only processes the X-ray energy received form the remnant radiation exiting the patient (D).

Which of the following is a phosphor most likely to be used in an indirect digital radiography system? A. BaSO4 B. CsI C. NaCl D. a-Se

B. CsI (B) Cesium iodide is a material used in the receptor of indirect digital radiography systems. X-ray energy is converted to light energy, which is then converted to an electrical signal in the thin film transistor (TFT) array. Barium sulfate (BaSO4) is a positive contrast medium used in fluoroscopic and radiographic examinations of the gastrointestinal system (A). Sodium chloride (NaCl) is table salt and is not used in any radiographic imaging systems. Amorphous selenium is a material used in a direct digital radiography system image receptor. This material directly converts x-ray energy to electrical energy in the TFT convertor.

What form of filtering amplifies high frequencies to increase contrast of large structures? A. Smoothing B. Edge enhancement C. Window level D. Window width

B. Edge enhancement (B) Edge enhancement is the process of including fewer pixels in the averaging of neighboring pixels. When pixels are suppressed and fewer are included in the average, a shorter scale of contrast is produced. Masking or suppressing frequencies may result in loss of fine detail. Smoothing is the opposite process in which all neighboring pixels are used to find the average of an area to eliminate high-frequency noise. Window level and width are image manipulation controls, which adjust the brightness and contrast of the screen image. The higher the window level, the darker the image. The wider the window width, the lower the contrast.

Select the 3 correct statements regarding x-ray beam protective filtration A. Equipment operated above 70 kV must have at least 3.5 mm Al equivalent. B. Filtration removes low-energy x-rays from primary beam, thereby reducing patient skin dose C. Filtration removes low-energy x-rays from primary beam, thereby decreasing the average energy of the beam. D. Filtration is usually expressed in millimeter of Pb equivalent. E. Filtration removes low-energy x-rays from primary beam, thereby increasing the average energy of the beam. F. Filters are built into the x-ray tube construction or added to the x-ray tube

B. Filtration removes low-energy x-rays from primary beam, thereby reducing patient skin dose E. Filtration removes low-energy x-rays from primary beam, thereby increasing the average energy of the beam. F. Filters are built into the x-ray tube construction or added to the x-ray tube X-ray photons emanating from the target/focal spot comprise a polyenergetic primary beam. There are many low-energy photons that are diagnostically useless and could contribute significantly to patient skin dose. Aluminum filters remove these low-energy photons, thereby decreasing beam intensity as well. X-ray beam filtration results in an x-ray beam of higher average energy. Total filtration is composed of inherent filtration plus added filtration. Inherent filtration is "built-in" filtration, composed of materials that are a permanent part of the x-ray tube and its tube housing. Added filtration refers to thin sheets of aluminum added to make the necessary total thickness of Al equivalent. NCRP guidelines state that equipment operating above 70 kV must have a minimum total (inherent plus added) filtration of 2.5 mm Al equivalent. Equipment operating between 50 and 70 kV must have at least 1.5 mm Al equivalent filtration; those operating below 50 kV must have at least 0.5 mm Al equivalent filtration.

The risk of occupational exposure is more significant in which 3 of the following? A. Lumbar spine imaging B. General fluoroscopy C. Scoliosis series D. Mobile imaging E. Interventional procedures

B. General fluoroscopy D. Mobile imaging E. Interventional procedures Radiographers are at greater risk of occupational exposure in procedures that involve general fluoroscopy, mobile procedures, fluoroscopy, and (interventional) procedures that employ high-level control fluoroscopy (HLCF). Personnel exposure is the result of scattered radiation from the patient; potential dose rate at 1 m from the patient can be several mGya/hr. The highest exposure rate from scatter is from the patient surface that the x-ray beam enters, that is, the surface closest to the x-ray tube. This is typically the approximate position of the fluoroscopist. Scattered radiation exposure rate decreases at 45° from the entrance surface and considerably more at right angles to the entrance surface. The lowest exposure position them is perpendicular to the patient/x-ray entry surface.

All the following statements regarding x-ray production are true, except: A. X-ray production efficiency is independent of tube current B. High-speed electron interaction with inner shell target atoms results in Brems radiation C. X-ray production efficiency increases with increasing kV D. Heat production increases with increasing kV

B. High-speed electron interaction with inner shell target atoms results in Brems radiation (B) X-ray photons are produced in two ways when high-speed electrons are rapidly decelerated at the anode target. First, if the course/direction of the high-speed electron is changed as it is attracted by the positive nucleus of a tungsten atom, energy is given up in the form of an x-ray photon as the electron is slowed or "braked". This is called bremsstrahlung (braking) radiation and is responsible for the majority of x-ray photons produced at the conventional tungsten target. Second, a high-speed electron may eject a tungsten K (inner) shell electron, leaving a vacancy in that shell. An electron from a higher energy level (for example, the L shell) drops down to fill the vacancy, emitting the difference in energy as a K-characteristic ray. Characteristic radiation comprises only approximately 15% of the primary beam. X-ray production is a very inefficient process; typically only about 1% of electron kinetic energy is converted to x-ray photon energy-the remainder of that energy is changed to heat. Although x-ray production efficiency increases with increasing kV, there is a corresponding increase in the production of heat at increasing kV

Which of the following radiographic contrast media is characterized by having the property of molecular dissociation into two charged particles when becoming part of a solution? A. Barium B. Ionic contrast C. Iodinated contrast D. Positive contrast

B. Ionic contrast The term ionic refers to the tendency of a molecule to become ionized, split into two charged particles, when introduced into a solution. Contrast media with this characteristic is called ionic contrast. Because splitting the molecules into two charged particles doubles the number of particles in the solution, ionic contrast has higher osmolarity than non-ionic contrast. Osmolarity is a description of the concentration of a solution. Because ionic contrast has a higher osmolarity than blood, it has a greater tendency to cause adverse reactions than non-ionic. Ionic and non-ionic contrast are two types of iodinated contrast media.

In digital fluoroscopy, a charge-coupled device A. Replaces the film used in a conventional fluoroscopy unit B. Is used instead of a camera in a conventional fluoroscopy unit C. Eliminates electronic noise in the image D. Minimizes the analog image produced at the input phosphor

B. Is used instead of a camera in a conventional fluoroscopy unit A major change from conventional fluoroscopy to digital fluoroscopy is the use of a charge-coupled device, or CCD, which replaces the need for a television camera tube. The CCD contains crystalline silicon, which, when illuminated, an electrical charge (signal) is produced, followed by a digital conversion of this signal to produce the image on the monitor. Radiographic film was used in a conventional (analog) fluoroscopic unit to record a static radiographic exposure. It is not a component of the television image chain in a conventional/analog fluoroscopic unit, nor is it involved in the analog to digital conversion that takes place in a digital fluoroscopic unit. Electronic noise is inherent in digital fluoroscopic and radiographic systems and is objectionable in the images produced. The CCD captures the light produced by a scintillator and a corresponding charge is produced relative to the intensity of the x-ray exposure. The CCD is located on the output side of the fluoroscopic tube. The analog image produced at the input side is produced by the remnant x-rays exiting the patient's body (D).

If a digital radiographic image is produced of a patient's body part and the radiographer did not collimate as closely as would be preferred prior to the exposure, the radiographer should do which of the following during post-processing of the image? A. Use digital masking (shuttering) on the image prior to sending it to the radiologist B. Leave all exposed areas of the anatomy visible on the final image sent to the radiologist C. Repeat the projection with optimal collimation, then submit the image to the radiologist D. Use the smoothing function to eliminate scatter fog in the image prior to submitting the image to the radiologist

B. Leave all exposed areas of the anatomy visible on the final image sent to the radiologist Masking, or shuttering, should never be used in in lieu of proper collimation during a radiographic exposure. Any anatomy that was included in the original image should be submitted to the radiologist, as there may be incidental pathological findings. Masking (shuttering) may eliminate anatomical areas that would otherwise be visible to the radiologist. Digital masking (shuttering) of a poorly collimated radiographic image should not be done, as review of exposed anatomy that was included in the original image should not be withheld form the radiologist's inspection (A). A poorly collimated radiographic projection should not be repeated, as this will only potentially double the patient's radiation dosage for that particular projection, which does not follow the principle of ALARA. The smoothing function does not eliminate scatter fog inherent to the original image

A larger dynamic range in a digital image represents A. Fewer gray tones displayed B. More gray tones displayed C. Higher spatial resolution D. A greater signal-to-noise ratio

B. More gray tones displayed The dynamic range is determined by the pixel depth, which determines the contrast resolution in the digital image. For example, if a pixel has a bit depth of 8, then the number of gray tones the pixel can display is 2 to the power of the bit depth (8), or 256 shades of gray. Two to the power of 20 would display 4096 shades of gray (B). A larger dynamic range demonstrates more shades of gray, not less (A). The number of pixels within a matrix determines the spatial resolution. A larger number of pixels within a matrix equates to smaller individual pixel sizes. Smaller pixels therefore have a smaller pixel pitch, which is the distance from the center of a pixel to an adjacent pixel. Smaller pixel pitch provides increased spatial resolution (C). Exposure affects the signal-to-noise ratio (SNR) in the digital image. As the (SNR) increases, the noise decreases, but at a cost of higher exposure to the patient (D)

The brightness of a pixel depends on all of the following, except: A. Bit depth B. Pixel pitch C. The exposure intensity D. Brightness setting of the monitor

B. Pixel pitch The pixel pitch relates to the distance between the center of one pixel to the center of an adjacent pixel in an image matrix (B). Bit depth refers to the range of gray (brightness) tones that a pixel can display (A). The exposure intensity determines the gray (brightness) value displayed by a pixel (C). The brightness on the monitor display can be adjusted during post-processing according to the evaluator's preference (D)

The basic methods of radiation protection are: A. Collimation, time, no repeats B. Shielding, time, distance C. Collimation, distance, gonadal shielding D. Time, distance, collimation

B. Shielding, time, distance Time, distance, and shielding can be used to reduce the exposure to the patient and the radiographer. To reduce the exposure to the patient: Reduce the amount of beam on time, use as much distance between the tube and the patient as possible for the examination, and always shield the patient. To reduce the exposure to the radiographer: Shorten the length of time spent in a room when x-rays are being produced, stand the greatest distance from the x-ray beam, and always use a radiation- absorbent shielding material between the radiographer and the source of radiation (B)

The Nyquist frequency is directly related to A. Contrast resolution B. Spatial resolution C. Signal-to-noise ratio D. Field of view

B. Spatial resolution The Nyquist theorem states that when sampling a signal in a digital system (such as the conversion of an analog signal to a digital signal), the sampling frequency must be greater than twice the frequency of the input signal so that reconstruction of the original image will be as close to the original signal as possible. At least twice the number of pixels needed to form the image must be sampled. If too few pixels are sampled, there will be a lack of spatial resolution. When the spatial frequency is greater than the Nyquist frequency and the sampling occurs less that twice per cycle, information is lost and a fluctuation signal is produced, causing an undesirable effect called aliasing, which appears as two superimposed images that are slightly out of alignment, resulting in a moiré effect (B). The image contrast is determined by the pixel depth or dynamic range of the pixels, which determines contrast resolution (A). Signal-to-noise ratio (SNR) depends on the digital system detectors and exposure. As the SNR increases, the noise decreases, but at a cost of higher patient dosage (C). The size of the field of view is determined by the collimated area of X-ray exposure. When imaging a patient using digital imaging, the radiographer selects the matrix size for the examination, referred to as the field of view (FOV). In this case, the dimension of the matrix size is used to represent the FOV and is the dimension of the anatomical part being radiographed. Increasing the field of view will not reduce the pixel pitch, which is the distance between the middle of one pixel to the middle of an adjacent pixel, which is controlled by the fixed matrix size of the digital imaging system.

For the superioinferior tangential (axial) projection of the nasal bones, the IR is placed at an angle underneath the chin. Which of the cranial positioning lines must the IR be in a perpendicular relationship to? A. The orbitomeatal line (OML) B. The glabelloalveolar line (GAL) C. The lipsmeatal line (LML) D. The acanthiomeatal line (AML)

B. The glabelloalveolar line (GAL) Aligning the IR perpendicular to the glabelloalveolar line (GAL) allows for the nasal bones to be imaged free of superimposition from surrounding bony anatomy. By placing the IR at an angle under the chin supported by cushions, this position limits discomfort for those with limited neck mobility. Placing the IR perpendicular to the orbitomeatal line (OML), lipsmeatal line (LML), and acanthiomeatal line (AML) would all result in superimposition by surrounding bony anatomy.

Images recorded as part of a radiographic exam are legally a part of the patient's medical record and are the property of what individual or entity? A. The patient B. The institution in which they were performed C. The interpreting radiologist D. The ordering physician

B. The institution in which they were performed Radiographic images are legal documents and are treated as part of the medical record. The patient may request copies and must sign a release to obtain images of transfer images to another provider or institution. Images are the property of the institution in which they were performed and are stored, either physically or electronically by that institution for a minimum of 5 years

Spatial resolution is determined by A. The number of gray tones that can be demonstrated in the pixel image B. The minimum distance between two anatomical structures that can be recognized as separate structures in the pixel image C. The size of the field of view D. The pixel bit depth

B. The minimum distance between two anatomical structures that can be recognized as separate structures in the pixel image Spatial resolution is determined by the pixel pitch in a matrix. The pixel pitch is defined as the distance measured from the center of one pixel to an adjacent pixel (B). The number of gray tones that can be demonstrated in the pixel image is determined by the dynamic range of the pixels, or bit depth (A). The size of the field of view is determined by the collimated area of X-ray exposure (C). The pixel bit depth is the dynamic range, or number of gray tones, that can be displayed by the pixels in an image matrix (D).

All of the following statements below regarding stochastic effects of radiation are true, except: A. Likelihood of stochastic effect occurrence depends upon the radiation dose B. The severity of any stochastic effect is dependent upon the radiation dose C. Stochastic effects include heritable genetic effects and some somatic effects D. Stochastic effects are late effects of ionizing radiation exposure

B. The severity of any stochastic effect is dependent upon the radiation dose (B) Stochastic (or Probabilistic) effects include heritable genetic effects and some somatic effects. They are the foremost late effects that are expected to occur in populations exposed to ionizing radiation; somatic effects (i.e., radiation- induced cancer) are the leading health detriment. With stochastic effects, the probability of their occurrence—but not their severity—is dependent on the radiation dose. However, for most stochastic effects, it is generally accepted that there is no threshold, that is, no safe dose. Radiation-induced cancers and genetic effects cannot be distinguished from those that appear spontaneously

Select the three phrases that are associated with Compton interactions: A. low energy incident photon B. predominates in the diagnostic x-ray energy range C. characteristic radiation is produced D. portion of incoming photon energy is transferred E. is directly related atomic number F. responsible for increased patient dose G. results in ionization and scattered photon

B. predominates in the diagnostic x-ray energy range D. portion of incoming photon energy is transferred G. results in ionization and scattered photon (B,D,G) In the diagnostic x-ray range of energies, attenuation is principally attributable to the two major types of interactions that occur between x-ray photons and tissue: the Photoelectric Effect and Compton interactions; Compton interaction predominates in the diagnostic range. In Compton interaction, a fairly high-energy (high kV) x-ray photon uses some of its energy to eject an outer shell electron, creating a positive ion. Although the x-ray photon is deflected with somewhat reduced energy (modified scatter), it retains most of its original energy and exits the body as an energetic scattered photon - potentially creating scattered radiation image fog and posing a radiation hazard personnel (as in fluoroscopic procedures). Because the scattered photon exits the body, it poses little radiation hazard to the patient. Some internal scatter, however, can contribute to patient dose. Compton interaction is unrelated to tissue atomic number, although atomic number is directly related to Photoelectric interaction.

X-ray photons leaving the anode are referred to as the A. remnant beam B. primary beam C. leakage radiation D. scattered radiation

B. primary beam (B) X-ray photons leaving the anode focal spot comprise the primary/useful beam; these are the x-ray photons before they interact with anything. X-ray photons that traverse the part and reach the image receptor/detector are referred to as the remnant/exit beam. Leakage radiation is that which is emitted from the x-ray tube housing in directions other than that of the primary/useful beam. Scattered radiation occurs when useful x-ray photons strike any object, causing the x-ray photons to change direction.

Select the three statements correctly identifying characteristics of the female/gynecoid pelvis A. narrow and more vertical B. shallow, from anterior to posterior C. pelvic inlet large and round D. pubic angle 100°or more E. deep from front to back F. pubic angle less than 90°

B. shallow, from anterior to posterior C. pelvic inlet large and round D. pubic angle 100°or more The typical female (gynecoid) pelvis differs from the typical male (android) pelvis in that it is shallower from front to back and its bones are generally more delicate. The pelvic outlet is wider and more circular in the female; the ischial tuberosities and acetabula are further apart; and the angle formed by the pubic arch is also greater in the female (100°or more). These bony characteristics facilitate the birth process.

The exposure rate caused by scatter emerging from the patient during fluoroscopic procedures is greatest at A. the exit surface of the patient B. the entrance surface of the patient C. the patient surface away from the x-ray tube D. right angles to the patient

B. the entrance surface of the patient Radiographers are at greater risk of occupational exposure in procedures that involve general fluoroscopy, mobile procedures, fluoroscopy, and (interventional) procedures that employ high-level control fluoroscopy (HLCF). Personnel exposure is the result of scattered radiation from the patient; potential dose rate at 1 m from the patient can be several mGya/hr. The highest exposure rate from scatter is from the patient surface that the x-ray beam enters, that is, the surface closest to the x-ray tube. This is typically the approximate position of the fluoroscopist. Scattered radiation exposure rate decreases at 45° from the entrance surface and considerably more at right angles to the entrance surface

The application of pressure to LCD screens can be the cause of 1. "dead" pixels 2. "stuck" pixels 3. Mitotic pixels A. 1 only B. 2 only C. 1 and 2 only D. 1, 2, and 3

C. 1 and 2 only (C) Pixels must receive a controlled electrical charge in order to perform their task. The pixels are located on the LCD monitor surface just below a very thin plastic layer. Pressure to that layer can cause pixel damage, resulting in "stuck" or even "dead" pixels- i.e. pixels that receive inconsistent or continuous charge.

Radiography students younger than 18 years must not exceed what dose limit? A. 50 mSv B. 5 mSv C. 1 mSv D. 0.5 mSv

C. 1 mSv Occupationally exposed individuals typically receive small amount of low-energy radiation over the course of their careers. Therefore, these individuals are concerned with the potential long-term effects of radiation, such as carcinogenesis (including leukemia) and cataractogenesis. According to the NCRP, the annual occupational whole-body dose-equivalent limit is 50 mSv. Because the established occupational dose-limit guideline is used for exposed persons 18 years of age and older, guidelines had to be established to cover the event that a student entered the clinical component of a radiography educational program prior to age 18. The guideline states that the occupational dose limit for students younger than 18 years is 1 mSv in any given year. The annual occupational dose-equivalent limit for the lens of eye is 150 mSv. The annual occupational dose-equivalent limit for the thyroid, skin, and extremities is 500 mSv. The total gestational dose-equivalent limit for embryo/fetus of a pregnant radiographer is 5 mSv but must not to exceed 0.5 mSv in 1 month.

The following is/are associated with the photoelectric interaction: 1. Outer shell interaction 2. Total absorption of incident photon 3. Low energy incident photon A. 1 only B. 1 and 2 only C. 2 and 3 only D. 1, 2, and 3

C. 2 and 3 only (C) In the photoelectric effect, a relatively low-energy x-ray photon uses all its energy (true/total absorption) to eject an inner shell electron, leaving an orbital vacancy. The ejected electron is the photoelectron. An electron from the shell above drops down to fill the shell vacancy and, in doing so, gives up energy in the form of a characteristic ray. The photoelectric interaction is more likely to occur in absorbers having high atomic number (e.g., bone and positive contrast media) and contributes significantly to patient dose, because all the photon energy is absorbed by the part.

The types of secondary radiation include 1. Remnant radiation 2. Scattered radiation 3. Leakage radiation A. 1 only B. 1 and 2 only C. 2 and 3 only D. 1, 2, and 3

C. 2 and 3 only (C) X-ray photons leaving the anode focal spot comprise the primary/useful beam; these are the x-ray photons before they interact with anything. The types of secondary radiation are leakage and scattered. Leakage radiation is that which is emitted from the x-ray tube housing in directions other than that of the primary/useful beam. Regulations state that leakage radiation must not exceed 1 mGya/hr when measured at 1 meter. Scattered radiation occurs when useful x-ray photons strike any object, causing the x-ray photons to change direction. Scattered photons can be damaging to image quality and can pose a safety hazard to personnel

In a digital image, a metallic object would appear as A. A medium gray value B. A dark gray value C. A white value D. A black value

C. A white value Digital detectors that receive little or no exposure will demonstrate a brightness in the image. Metallic objects in the anatomy would absorb x-rays and, therefore, little or no x-ray energy would reach the detectors, which would be similar to those values displayed by the area collimated off during the exposure. Again, no exposure to an area of the detectors are displayed by white bright values (C). The brightness values change across a histogram relative to the exposure received in various portions of the exposure field (field of view). Therefore an anatomical image will be displayed with bright areas at the left of the histogram and progressively become darker toward the right side of the histogram. Therefore, one would expect metallic objects to appear at far left, then followed by bone, soft tissue, then gas or raw x-ray exposure outside of the anatomical part. A medium gray value may represent soft tissue (A). A dark gray value (B) or black area (D) may represent thinner portions of soft tissues or gas or air, respectively (B, D).

Which of the following anatomical structures is best demonstrated in an axiolateral oblique projection of the mandible when a 30° rotation toward the IR is utilized? A. Mentum B. Ramus C. Body D. Condyloid process

C. Body The axiolateral oblique projection can be utilized to demonstrate various anatomical structures of the mandible. A 30° rotation is utilized to demonstrate the body, while the mentum is visualized best with a 45° rotation toward the IR. In a true lateral position, the rami is of interest. A 10-15° rotation obtains the mandible without attention to a particular anatomical structure. The best projection to view the condyloid processes is the AP or PA axial of the mandible.

If a radiation-damaged cell ceases its efforts to repair itself, this is called A. Synthesis B. Based damage C. Cell cycle arrest D. Apoptosis

C. Cell cycle arrest C) The majority of cell damage occurring after irradiation is repairable. The three types of potential damage to DNA are base damage, single-strand break, and double-strand break. Of these, base damage and single-strand break are more readily repairable while double-strand DNA break can be more problematic. In cell cycle arrest, the cell can temporarily stop trying to repair itself. Cell cycle arrest can occur between the G1 (Gap 1) and S (Synthesis) stages, during S, or between G2 (Gap2) and M (mitosis). The human body works to take care of its whole unit. If a cell and/or its genetic content is damaged enough so that its progeny could lead to production of malignant neoplasm or death of the whole unit, it is far better that the cell be sacrificed for the well-being of the whole unit (entire body). That is termed apoptosis, or "cell suicide", for the benefit of the whole unit.

Defective pixels that do not function at all are called A. Lag pixels B. Displaced pixels C. Dead pixels D. Ghost pixels

C. Dead pixels (C) During the manufacture of digital detectors, it is possible for a pixel to become damaged, rendering it nonfunctional. This pixel is called a dead pixel. Image lag refers to the lingering of an image from a previous exposure, which produces a double exposed image. Pixels are arranged in a fixed array and do not migrate to other areas in the detector system. When there is Inadequate erasure of a receptor image, the previous exposure is superimposed as a ghost image on the current image.

Which of the following statements is TRUE about the five stages of grieving, as described by Dr. Elizabeth Kubler-Ross? A. The five stages generally occur in order. B. When a person is in the "denial" stage, medical professionals should try to overcome the denial by stating the truth. C. During the "anger" stage, it is possible that the person will take out anger at the situation on family or healing professionals. D. Each person dealing with grief will experience all five stages at some time during the grieving process.

C. During the "anger" stage, it is possible that the person will take out anger at the situation on family or healing professionals. The five stages of grief, described by Kubler-Ross, changed the way medical professionals view the grief associated with loss or death. The grieving process is different based on the individual, but the 5 common stages identified are denial, anger, bargaining, depression, and acceptance. The stages may occur in any order and the person may go back and forth between stages. As caring professionals, being understanding of the grieving process may help in reminding the professional not to take personally the misdirection of anger or rage that can result when a patient feels helpless or lacking in control.

What is the purpose of using filtration in regards to minimizing the patient exposure? A. It increases the patient dose so you can lower your technique B. It allows you to see where you should be aligning the tube C. It is used to selectively absorb low-energy photons D. It allows for adequate gonadal shielding

C. It is used to selectively absorb low-energy photons Filters are placed at the x-ray port to selectively absorb low-energy photons that would be absorbed by the patient and not contribute to the image (C). When filtration is increased, technical factors need to be increased to compensate for the reduction in exposure associated with filtration (A).

The condition characterized by degeneration of articular cartilage is termed A. Osteomyelitis B. Osteopenia C. Osteoarthritis D. Osteomalacia

C. Osteoarthritis (C) Osteoarthritis is the degeneration of articular cartilage at the ends of large bones causing swollen and painful joints. Rheumatoid arthritis is found in small joints. Osteopenia is any decrease in bone mass below normal. The rate of bone synthesis is too low to compensate for the normal process of bone resorption. Osteopenia is often a precursor for osteoporosis, a more severe condition of low bone density and deterioration of bone structure. Osteomyelitis is a bone infection caused by bacteria that results in fever, chills, pain, edema, and warmth over the affected bone. Osteomalacia is a disorder in which bone fails to calcify during remodeling causing painful and tender "soft" bones to form. This disorder is termed rickets in children when growing bones fail to ossify and become deformed.

The intrathecal route of drug administration falls into which category of administration? A. Enteral B. Topical C. Parenteral D. Intravenous

C. Parenteral The parenteral route of drug administration refers to any type of injection. This method bypasses the GI system and is the most direct means of drug administration. The intrathecal injection is an injection into the subarachnoid space of the spinal canal. Other parenteral routes include intradermal, subcutaneous, and intramuscular. Intravenous is the most commonly used parenteral method. Enteral refers to routes of drug administration via the GI tract. Topical medications are administered via the skin or mucous membrane.

What is the most dangerous source of radiation for the technologist who remains in the room during a fluoroscopic procedure? A. X-ray Tube B. Bucky C. Patient D. Primary Radiation

C. Patient The patient becomes a source of scattered radiation as a consequence of the Compton interaction process ©. (Sherer, Visconti, Ritenour, Hayes, 7th ed., p. 310) The x-ray tube is the component of the system that produces the x-rays (A). The bucky is a device that reduces the amount of scatter radiation by employing a grid (B). Primary Radiation is the x-ray beam traveling towards the patient after it leaves the x-ray tube and before it reaches the object (D

Which of the following is a legal doctrine that may apply in a medical malpractice case in which negligence would be obvious to any reasonable person? A. Repondeat superior B. Tort C. Res ipsa loquitor D. Attribution

C. Res ipsa loquitor The literal translation of the Latin term res ipsa loquitor is "the thing speaks for itself". This means that a breach of conduct on the negligence of the healthcare provider is almost undisputable. A tort is a civil case (not criminal) filed for intentional or unintentional misconduct by one person against another person or their property. The legal doctrine Repondeat superior is a Latin term meaning "let the master answer", and is applied when an employer is held responsible for a worker's actions.

Which of the following indicates the amount of exposure used in digital radiography? A. The degree of spatial resolution B. The degree of contrast resolution C. The exposure indicator D. The signal-to-noise ratio

C. The exposure indicator An important feature of digital X-ray imaging systems is the exposure indicator. This indicator provides a numeric value of the amount of exposure received by the image receptor. These indicators vary by vendor and, therefore, are not standardized. Regardless of the equipment used, the radiographer must be cognizant of the appropriate exposure levels for a given exam in alignment with the ALARA principle (C). Spatial resolution is inherent to the matrix size and cannot be changed. Spatial resolution is determined by the pixel pitch in a matrix. The pixel pitch is defined as the distance measured from the center of one pixel to an adjacent pixel (A). The image contrast is determined by the pixel depth, or dynamic range, of the pixels, which determines contrast resolution (B). Signal-to-noise ratio (SNR) depends on the digital system detectors and exposure. As the SNR increases, the noise decreases, but at a cost of higher patient dosage (D).

The dynamic range in a digital image is determined by the A. Field of view B. The amount of magnification in the image C. The pixel bit depth D. The matrix size

C. The pixel bit depth The dynamic range is determined by the pixel depth, which determines the contrast resolution in the digital image. For example, if a pixel has a bit depth of 8, then the number of gray tones the pixel can display is 2 to the power of the bit depth, or 256 shades of gray (C). When imaging a patient using digital imaging, the radiographer selects the matrix size for the examination, referred to as the field of view (FOV). In this case, the dimension of the matrix size is used to represent the FOV and is the dimension of the anatomical part being radiographed (A). The amount of magnification is determined by the SID and OID, and can also be manipulated using a post-processing technique, whereby the image can be magnified to better visualize anatomical areas of interest (B). The matrix size is determined by the number of image pixels in horizontal rows multiplied by the number of image pixels in vertical columns. The typical number of a matrix ranges from about 512 x 512 to 1024 x 1024 and can be as large as 2500 x 2500 (D).

Which of the following is an example of therapeutic non-verbal communication between a radiographer and patient? A. Radiographer stands with arms crossed while gathering patient history. B. Radiographer tells the patient that he or she will feel no pain during the procedure, but will not return the patient's eye contact. C. The radiographic examination room is neat and organized. D. The radiographer hugs the patient at the end of the exam because she seems anxious.

C. The radiographic examination room is neat and organized. Communication goes far beyond the spoken or written word. Non-verbal communication includes many visual cues, such as posture, clothing, gestures, and facial expression. Standing with one's arms crossed may indicate a defensive, mistrustful, or angry attitude. When body language doesn't match what is being communicated verbally, mistrust may result. A neat and organized exam room is a way of communicating non-verbally to a patient that the radiographer is prepared and attentive to detail and cleanliness. While some patients may respond well to physical touch and comfort, touch should be used judiciously as a form of non-verbal communication. In many cultures, a hug from a healthcare provider would be an uncomfortable violation of personal space and may be misinterpreted.

All of the following are characteristics of x-rays, except: A. X-rays are electrically neutral B. X-rays have a physiological effect on living tissue C. X-rays are focused in straight lines D. X-rays have a penetrating effect on all matter

C. X-rays are focused in straight lines (C) X-rays are infinitesimal bundles of energy called photons that deposit some of their energy into matter as they travel through it. This deposition of energy, and subsequent ionization, has the potential to cause chemical and biological damage. Several of the outstanding properties/characteristics of x-ray photons are listed below. X-rays are not perceptible by the senses X-rays travel in straight lines X-rays travel at the speed of light X-rays are electrically neutral X-rays have a penetrating effect on all matter X-rays have a physiological effect on living tissue X-rays have an ionizing effect on air X-rays have a photographic effect on film emulsion X-rays produce fluorescence in certain phosphors X-rays cannot be focused X-rays have a spectrum of energies

The type of personnel radiation monitor having an ionization chamber using Bluetooth technology is the A. pocket dosimeter B. optically stimulated luminescence dosimeter C. direct ion storage dosimeter D. thermoluminescent dosimeter

C. direct ion storage dosimeter The newest type of personnel monitoring device is the revolutionary direct ion storage dosimeter (DIS); it is a digital ionization dosimeter. The DIS eliminates the need to collect and send dosimeters for monthly or quarterly processing. The user wears the DIS, which looks like a small flash drive, in the same way as other monitors such as an OSL (optically stimulated luminescence dosimeter). The DIS has a gas-filled ionization chamber within and uses Bluetooth technology to relay its raw data via iPhone, iPad, other mobile device, or any computer with Internet access and a USB connection. Occupational exposure can be read, and reread, at any time without loss of information. The pocket dosimeter, or pocket isolation chamber, resembles a penlight and has a thimble ionization chamber within. Ions are counted and register radiation quantity in milliroentgen (mR). The use of a pocket dosimeter is indicated when working with high exposures or large quantities of radiation for a short period of time, so that an immediate reading is available to the user. The pocket dosimeter is sensitive and accurate, but has limited application in diagnostic radiography

Select the correct sequence of events that follow high level radiation exposure resulting in acute radiation syndrome A. manifest illness, prodromal period, latent period B. manifest illness, latent period, prodromal period C. prodromal period, latent period, manifest illness D. latent period, prodromal period, manifest illness

C. prodromal period, latent period, manifest illness (C) After a whole body exposure of 1 Gyt acute radiation syndrome (ARS) can occur within hours. The first stage of ARS is the period, characterized by nausea, vomiting, diarrhea and blood changes. Depending on the dose, prodromal stage can last from a few hours to 1-2 days. The second stage is the latent period, a time when earlier symptoms seem to have disappeared. The length of the latent period depends upon the dose received; the larger the dose, the shorter the latent period. The third stage is the manifest illness period when hematologic, gastrointestinal, in cerebrovascular effects manifest themselves. This last stage is followed by recovery or death. It must be emphasized that ARS requires a very large whole body exposure dose, only likely to be seen in nuclear power station accident (such as in Chernobyl, Soviet Union or atomic bomb fallout. A very large whole body exposure such as this would not occur in diagnostic imaging

In computed radiography (CR), energy stored in the PSP is stimulated in the scanner by A. low energy X-rays B. microwaves C. red light D. Ultraviolet light

C. red light The CR scanner's function is to expose and scan the PSP with a red light laser beam in a raster pattern. This causes release of stored energy generated from the X-ray exposure in the form of light. This light is subsequently captured by a mirror and projected onto a photomultiplier tube that converts the light energy into an electrical signal that is subsequently digitized by an analog-to-digital (A to D) convertor (C). Low energy X-rays are at a much higher frequency than those of microwaves and, therefore, would not stimulate release of energy sored in the PSP. There is a finite wavelength of electromagnetic wavelength energy that must be used to release the stored energy (A). Microwaves do not have the wavelength necessary to stimulate the PSP to release its stored energy (B). Ultraviolet light does not have the wavelength necessary to stimulate the PSP to release its stored energy (D).

Which of the following statements regarding the time on fluoroscopy machines is true? 1. It is a federal law that requires machines in the United States to an audible 5-minute timer. 2. Once 5 minutes has elapsed the radiographer must stop the procedure. 3. The timer can be set as many times as necessary to complete a procedure. A. 1 only B. 1, 2, and 3 C. 2 only D. 1 and 3 only

D. 1 and 3 only In the United States, federal law requires an audible 5-minute timer. Although, it can be reset as many times as necessary to complete a procedure, it is intended to serve as a reminder to the radiologist of how much total exposure time is being used. Fluoroscopy is interrupted when the 5 minutes have elapsed and the radiographer must reset the timer to continue the procedure (D).

Characteristics of tungsten that make it a useful component of x-ray tubes include 1. High melting point 2. Thermal conductivity 3. High atomic number A. 1 only B. 1 and 2 only C. 2 and 3 only D. 1, 2, and 3

D. 1, 2, and 3 (D) The anode is made to rotate through the use of an induction motor. An induction motor has two main parts, a stator and a rotor. Tungsten (W) is usually chosen as target material because of its high atomic number (Z = 74), high melting point (3410°C), and thermal conductivity (equal to that of copper). The high atomic number serves to increase the efficiency of x-ray production; its high melting point makes it resistant to pitting and cracking; its thermal conductivity helps dissipate the heat produced during x-ray production. Rhenium is added to further resist anode pitting at high temperatures. The cathode assembly consists of one or more filaments, their supporting wires, and a nickel focusing cup. The filament is a fine 1- to 2-cm coil of tungsten wire that, when heated to incandescence by approximately 4 A of current, boils off /releases outer shell tungsten electrons. This event is called thermionic emission. Most x-ray tubes actually have two or more filaments and are called double-focus tubes.

The NCRP recommends that the annual occupational exposure to the lens of the eye not exceed A. 5 mSv B. 15 mSv C. 50 mSv D. 150 mSv

D. 150 mSv The National Council on Radiation Protection and Measurements (NCRP) publishes a summary of occupational dose limit recommendations. The annual occupational exposure must not exceed 50 mSv; the cumulative effective dose limit must not exceed 10 mSv times X age in years. The lens of the eye is its most radiosensitive structure and its annual dose limit is 150 mSv. The dose limit to localized, less radiosensitive tissues such as the hands, skin, and feet is 500 mSv.

Radiation exposure should always be kept at the lowest possible level for the general public. Which of the following describes a medically justified procedure? 1. Tuberculosis screening chest x-rays 2. Hospital admission chest x-rays 3. Mammography screenings A. 1 only B. 1 and 3 only C. 1, 2, and 3 D. 3 only

D. 3 only Mammography screening continues to be the most cost effective and efficient tool for diagnosing breast cancer. When ionizing radiation is used for the general welfare of the patient, the benefits of the radiation exposure far outweigh the risk of radiogenic malignancy or any other genetic defects (D). Studies have shown that mass tuberculosis screening using x-ray have not been found effective (A). Chest x-ray examination for routine hospital admission should not be performed on patients with no clinical indication of chest disease(C).

In the circumstance that a patient is required to give informed consent for a procedure that involves risk or is experimental, which of the following truly defines informed consent? A. If the procedure is the same, the physician performing the procedure can be changed after consent is signed. B. A parent, grandparent, or legal guardian can sign for a minor. C. Informed consent cannot be revoked. D. A patient must receive full explanation of the procedure, risks, and benefits before being anesthetized.

D. A patient must receive full explanation of the procedure, risks, and benefits before being anesthetized. All conditions explicit on the informed consent form must be met in order to constitute informed consent. The physician performing the procedure must be the one named on the form. Only a parent or legal guardian may sign for a minor. Consent may be revoked by the patient at any time in accordance with the Patient Bill of Rights, the right to refuse treatment. The consent form is not valid if it is signed after the patient has received sedation or anesthesia

An optically stimulated luminescence dosimetry system is most likely to use which of the following active ingredients? A. Silver bromide B. Air C. Lithium fluoride D. Aluminum oxide

D. Aluminum oxide Optically stimulated luminescence (OSL) dosimeters are highly accurate. OSL dosimeters use aluminum oxide as their sensitive/active ingredient/crystal. TLDs are personnel radiation monitors that use lithium fluoride crystals as their active ingredient. Once exposed to ionizing radiation and then heated, these crystals give off light proportional to the amount of ionizing radiation received. TLDs are accurate personal monitors. Air is used as the active ingredient in pocket dosimeters and personal direct ion storage dosimeters (DIS). The DIS has a gas-filled ionization chamber within and uses Bluetooth technology to relay its raw data via mobile device or any computer with Internet access and a USB connection. Occupational exposure can be read, and reread, at any time without loss of information. Silver bromide is the active ingredient in film emulsion and is used in film badge dosimeters.

All of the following are found in a direct capture digital radiography system, except A. Photoconductor B. TFT C. Amorphous selenium D. Amorphous silicon

D. Amorphous silicon A photoconductor is used in a direct capture digital system, which eliminates the need for the additional X-ray-to-light energy conversion used in the indirect capture digital system. The photoconductor is made of amorphous selenium (a-Se) and the electrical charge produced within this substance when exposed to X-ray energy is directly converted to an electrical signal by the underlying thin film transistor (TFT) array, which sends this electrical energy to capacitors that amplify and convert the energy into binary code (A). The photoconductor in a direct capture digital system is made of amorphous selenium (a-Se) and the electrical charge produced within this substance when exposed to X-ray energy is directly converted to an electrical signal by the underlying thin film transistor (TFT) array, which sends this electrical energy to capacitors that amplify and convert the energy into binary code (B). In a direct capture digital system, the photoconductor is usually amorphous selenium (a-Se), although other photoconductors such as lead iodide, lead oxide, thallium bromide, and gadolinium compounds may be used. The use of a-Se, however, has become commonplace because of its excellent X-ray detection ability and very high spatial resolution is realized (C). The amorphous silicon photodiode is used in indirect capture digital systems. This diode, acting like an electrical switch, only allows electrical charges to be delivered in one direction toward the image processor, which converts this energy into a digital image (D).

All of the following contribute to the manifest digital image, except A. Matrix size B. Pixel bit depth C. Pixel pitch D. Analog signal

D. Analog signal The analog signal comprises the electrical signal (latent image) produced in either the direct or indirect capture digital systems, prior to being converted to a digital (manifest image) (D). The matrix size is determined by the number of image pixels in horizontal rows multiplied by the number of image pixels in vertical columns. The typical number of a matrix ranges from about 512 x 512 to 1024 x 1024 and can be as large as 2500 x 2500. Larger matrix sizes produce images with improved spatial resolution, as the pixels are smaller (A). Bit depth refers to the range of gray (brightness) tones that a pixel can display (A). The exposure intensity determines the gray (brightness) value displayed by a pixel (B). The pixel pitch relates to the distance between the center of one pixel to the center of an adjacent pixel in an image matrix (C).

All of the following pertain to the manner in which specific anatomic details are displayed in digital imaging, except: A. By specific pixels in the digital image B. As a specific portion of the image matrix C. As a digital image component displaying specific gray tones D. As a permanent set of brightness levels that cannot be changed

D. As a permanent set of brightness levels that cannot be changed Once an anatomical image is produced, it may be manipulated using post-processing techniques, whereas the brightness of the pixels can be altered (D). Specific anatomical parts are recorded by specific pixels, a specific portion of the image matrix, and as a digital component displaying specific gray tones corresponding to the remnant radiation (A, B, C).

Which of the following represents contrast resolution in the image acquisition process? A. Pixel B. Pixel size C. Pixel pitch D. Bit depth

D. Bit depth (D) Pixel bit depth is known as the number of bits within a pixel, which presents the number of gray tones that pixel can produce. The number of shades of gray can be calculated by raising 2 to the power of the bit depth, or 210 or 1,024 shades of gray. A pixel is the smallest element in a digital image. Pixel size is related to the spatial resolution. Pixel pitch is the distance between the centers of two adjacent pixels. The smaller the pixel and pixel pitch the greater the resolution.

Which of the following terms is used to describe a condition that can result from blunt trauma to the chest, in which the heart is bruised and can hemorrhage into the pericardium and prevent expansion of the heart? A. Hematoma B. Myocardial infarction C. Hemothorax D. Cardiac tamponade

D. Cardiac tamponade Hematoma is a bruise. Myocardial infarction (MI) is a heart attack, a condition that results from failure of delivery of oxygenated blood to the myocardium (heart muscle). Hemothorax is the condition of having blood in pleural space. Cardiac tamponade can be present, even with little exterior indication of injury. It can very quickly develop into a critical situation

The ability of a digital detector to convert an x-ray exposure into a useful image is called A. Contrast resolution B. Spatial resolution C. Pixel sampling D. Detective quantum efficiency

D. Detective quantum efficiency Detective quantum efficiency (DQE) is a measure of the efficiency and fidelity with which the IR can convert X-rays received (incident quanta) into a useful digital image (D). The image contrast resolution is determined by the pixel depth, or dynamic range, of the pixels, which determines contrast resolution (A). Spatial resolution is inherent to the matrix size and cannot be changed. Spatial resolution is determined by the pixel pitch in a matrix. The pixel pitch is defined as the distance measured from the center of one pixel to an adjacent pixel (B). Pixel sampling can be described as sampling frequency, which is the frequency at which a data sample is acquired form the detector and is expressed as sampling pitch. Sampling pitch describes how digital detectors sample the received X-ray exposure. In CR, the sampling pitch is the distance between the laser beam positions during scanning of the IP, and for digital systems it is the distance between detector elements (DEL) (C).

The PSP in computed radiography (CR) can retain residual energy from previous radiation exposures. Therefore, it is important for the radiographer to: A. Scan the PSP image plate a second time to capture additional anatomical information for the radiologist to interpret B. Reduce the exposure factors used during subsequent radiographic procedures to take advantage of the residual energy, thereby optimizing ALARA C. Remove this residual energy during image post-processing of the original image to avoid ghost image artifacts D. Erase any potential residual energy within the PSP by exposing the IP to intense light in the CR scanner

D. Erase any potential residual energy within the PSP by exposing the IP to intense light in the CR scanner (D) CR Image plates should periodically be erased using intense light in the CR scanner, as residual energy from previous radiation exposures may be retained within the IP for up to 8 hours. Scanning a CR IP a second time to extract residual stored energy would not produce any additional diagnostic information. Optimal exposure factors should be used for all radiographic procedures. Minimizing exposure factors based on residual stored energy in the CR IP is not practical, as this energy would provide erroneous information, which would only degrade the radiographic image. Post-processing of the original digital radiographic image cannot eliminate residual stored energy in the CR IP. Proper erasure of residual stored energy in the CR IP should be a regular practice of the radiographer to avoid ghost images on subsequent radiographs.

All of the following have an inverse relationship, except A. Pixel size/spatial resolution B. Collimation/patient exposure C. Matrix size/pixel size D. FOV/patient exposure

D. FOV/patient exposure As the field of view (FOV) increases, so does the anatomical area of x-ray exposure. Therefore, patient exposure (and dose) increases as the FOV increases, which is a direct relationship (D). As pixel size decreases, spatial resolution increases, and vice versa (A). As collimation increases, the areas of the patient's body exposed decreases (B). As matrix size increases, pixel size decreases (C).

Which of the following is necessary to prove when claiming a case of malpractice? A. Negligence occurred but did not result in an injury or loss to the patient B. Defendant provided mediocre care for the patient C. Plaintiff's actions contributed to the injury or loss D. Improper practices by the defendant caused the injury

D. Improper practices by the defendant caused the injury Due to the defendant's (radiographer's) lack of proper practices, the plaintiff (patient) was injured (D). If the radiographer demonstrated negligence, the patient must have incurred an injury or loss in order to file a malpractice case (A). The radiographer is responsible for providing reasonable care to the patient (B). The radiographer's actions or lack of action results in an injury to the patient. In this situation, the patient's actions did not cause the injury or loss (C).

Patient demographic information is critical in digital radiography systems because of all of the following, except A. It is tied to an MRN or accession number that can be retrieved for viewing or stored in a PACS B. Ensures the correct diagnosis is matched with the correct patient C. Enables proper billing to the correct patient D. It enables the system to use a histogram that is most appropriate for the patient

D. It enables the system to use a histogram that is most appropriate for the patient The histogram is an anatomy-specific template-matching algorithm stored within the computer and is used for any patient undergoing a radiographic exam of a particular anatomical part. It is independent of the demographic information provided (D). Patient demographic information is critical in digital radiography, as the images created must be accurately retrieved for viewing or stored in a PACS for future reference (A). Demographic information is matched with an accession number and patient identification number that ensures that the diagnosis is matched to the correct patient (B). Demographic information also ensures that the correct patient is billed for the radiologic services rendered (C).

Which of the following personnel monitoring devices are regarded as being the most sensitive? A. Pocket ionization chamber B. Film badge C. Thermoluminescent dosimeter D. Optically stimulated luminescence dosimeter

D. Optically stimulated luminescence dosimeter The optically stimulated luminescence dosimeter has increased sensitivity, providing accurate readings as low as 1 mrem for x-ray and gamma ray photons with energies from 5 keV to 40 MeV (D). Pocket ionization chambers are not commonly used to monitor exposure to medical imaging personnel (A). The radiation-dosimetry film inside a film badge is sensitive to doses ranges from 10 mrem to 500 rem (B). A thermoluminescent dosimeter provides readings as low as 5 mrem (C).

Which interaction is most likely to be associated with increased patient dose? A. Bremsstrahlung B. Compton C. Coherent D. Photoelectric

D. Photoelectric (D) In Photoelectric interaction, a low-energy x-ray photon is totally absorbed by the part as it ejects an inner shell electron. The photoelectric interaction is more likely to occur in tissue absorbers that have high atomic number, and it contributes significantly to patient dose. The process of coherent interaction occurs infrequently in diagnostic imaging and is the only interaction between x-ray photons and matter in which no ionization occurs. Compton interaction predominates in the diagnostic range. It involves a high-energy x-ray photon interacting with an outer shell electron, producing an ion and scattered x-ray photon. The x-scattered photon retains most of its original energy and exits the body, potentially creating scattered radiation image fog and posing a radiation hazard personnel. Because the scattered photon exits the body, it poses little radiation hazard to the patient. Bremsstrahlung is associated with x-ray production.

All of the following are types of digital imaging artifacts, except A. Aliasing B. Image compression C. Collimation D. Pixel pitch

D. Pixel pitch (D) The pixel pitch relates to the distance between the center of one pixel to the center of an adjacent pixel in an image matrix, which is a physical characteristic of the digital detector system that cannot be changed. Smaller pixel pitch provides increased spatial resolution. The Nyquist theorem states that when sampling a signal in a digital system (such as the conversion of an analog signal to a digital signal), the sampling frequency must be greater than twice the frequency of the input signal so that reconstruction of the original image will be as close to the original signal as possible. At least twice the number of pixels needed to form the image must be sampled. If too few pixels are sampled, there will be a lack of spatial resolution. When the spatial frequency is greater than the Nyquist frequency and the sampling occurs less that twice per cycle, information is lost and a fluctuation signal is produced, causing an undesirable effect called aliasing, which appears as two superimposed images that are slightly out of alignment, resulting in a moiré effect. Transmitting and archiving large data images is technically difficult. There are two methods of compressing the data transmitted via teleradiology: lossless and lossy. Data compression takes advantage of redundancy of data, as occurs with exposure to the raw x-ray beam when all values are the same. Lossless compression allows the file to be reconstructed to be exactly the same as the original image, whereas lossy compressed files cannot and such compression is therefore reserved for images that do not need to recreate fine details. However, if fine details are needed and the image was compressed using the lossy method, this may cause the computer-aided detection (CAD) system to miss lesions because of the compression artifact, which represents a lack of data. Lossy compression is not acceptable for transmitting and archiving mammography images for this reason. Poor collimation not only increases patient dosage, but may cause a histogram analysis error image artifact. The cause of these artifacts is algorithm related, whereby the exposure recognition algorithm is unable to match image histograms if the fields (edges and area) are not clear (C).

Review the following sets of vital signs for adult female patients. Which patient displays a reading that falls outside of the normal range? A. Pulse: 68 bpm, respiration: 15 breaths per minute, blood pressure: 100/70 B. Pulse: 95 bpm, temperature (oral): 98.7, blood pressure: 95/68 C. Respiration: 17 breaths per minute, temperature (oral): 98.6, pulse: 75 bpm D. Temperature (oral): 98.6, blood pressure: 135/79, respiration: 13 breaths per minute

D. Temperature (oral): 98.6, blood pressure: 135/79, respiration: 13 breaths per minute Normal vital signs for an adult female are as follows: temperature (oral)- 98.6 degrees F, pulse- 60-100 BPM, respiration- 12-20, blood pressure < 120 mm Hg systolic and < 80 mm Hg diastolic. Systolic pressure of 135 was previously considered to be within normal range, but is now considered to be within the pre-hypertensive range (120-139).

When dealing with a pediatric patient as young as 3 or 4 years of age, what should be your first choice in regards to immobilizing the patient? A. Sheet Restraints B. Pigg-O-Stat C. Plexiglas paddle D. Try to gain the trust of the child by communicating on their age level

D. Try to gain the trust of the child by communicating on their age level The technologist should take the time to sit down with the patient and parents and speak to the child on their level. Most of the time, this will eliminate the need for restraints (D).

Using post-processing, a radiographer can enhance the subject contrast when using CR by: A. Increasing the kilovoltage B. Using increased filtration of the primary beam C. Increasing OID D. Using a narrower window width setting to display image

D. Using a narrower window width setting to display image Using a narrower window width to display a CR image produces an image with a shorter scale of contrast (fewer intermediate gray tones), thereby increasing contrast between adjacent structures in the part being radiographed (D). Increasing kilovoltage increases the primary beam's penetrability, therefore anatomical structures that would otherwise attenuate the beam through photoelectric interactions will allow an increased number of primary photons to exit the part and expose the receptor. Even though the widow width can be adjusted to enhance the image contrast, it does not eliminate the fact that the anatomical part (say, bone) was overpenetrated (A). Increased filtration hardens the primary beam by eliminating a greater number of low energy photons, thereby effectively increasing the average energy (penetrability) of the beam. Increased primary beam energy would therefore increase penetration of anatomical structures that would otherwise absorb photons and produce increase subject contrast (B). Increasing the OID to provide an air gap technique can eliminate some scatter from reaching the image receptor (IR). This can reduce the number of scattered photons reaching the IR, but this would not be a controlling factor of subject contrast (C)

If a physician were to complain about poor spatial resolution seen in radiographic images produced in a medical imaging department, the best technical solution would be which of the following? A. Have radiographers increase collimation B. Have radiographers use the smoothing function during post-processing C. Have radiographers increase the field of view D. Utilize a larger matrix size to produce the images

D. Utilize a larger matrix size to produce the images (D) Although it would be expensive to change the matrix size used in producing radiographic images, this would be the best solution to this problem. It is important to encourage physicians (not only radiologists) to provide feedback on radiographic image quality when considering purchasing a digital radiography system. Increased collimation will not have any effect on the spatial resolution in a fixed matrix display. The smoothing function used during post-processing does not have any effect on the spatial resolution inherent to the matrix size used in the digital imaging system. Increasing the field of view will not reduce the pixel pitch, which is the distance between the middle of one pixel to the middle of an adjacent pixel, which is controlled by the fixed matrix size of the digital imaging system (C).