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Which of the following changes in (KVP) will result in the greatest reduction of patient dose, when (MAS) is adjusted to compensate for the change? - ANS>> Increase kVp by 30% Which of the following (IR) system speeds will result in the lowest patient dose? - ANS>> Faster speed IR system What is the primary purpose of using gonad shields during radiography? - ANS>> Reduce the likelihood of genetic effects Contact & shadow are two types of gonad shield - ANS>> TRUE When should gonad shields be used? - ANS>> When the gonads are within 5cm of the radiation field The greatest cause of unnecessary radiation to patients that can be controlled by the limited operator are: - ANS>> repeat exposures The limited operator can reduce repeat exposures by: - ANS>> clearly instructing patients How does x-ray beam restriction minimize patient exposure - ANS>> It limits the radiation field to the area of interest What is the device that allows the limited operator to vary the size of the radiation field - ANS>> Collimator How does filtration reduce patient exposure - ANS>> Removes longer wavelength photons What is the National Council on Radiation Protection and Measurements (NCRP) recommendation for the amount of total filtration - ANS>> 2.5mm Al Equivalent What are the three principal methods used to protect limited operators from unnecessary radiation exposure? - ANS>> 1. Time
- Distance
- Shielding Which of the following is NOT a type of personnel radiation shielding? - ANS>> a. Apron b. Glove c. Thyroid shield d. Shadow******** CORRECT Personnel shielding must be worn on the rare occasion during which the limited operator may need to remain in the radiographic room during an exposure to assist the
patient in maintaining the proper position. What is the source of the greatest radiation hazard under this circumstance? - ANS>> Scattered radiation from the patient What is the term from radiation that escapes from the x-ray tube housing? - ANS>> leakage radiation Why are limited operators prohibited from activities that result in direct exposure to the primary x-ray beam? - ANS>> They are considered occupationally exposed individuals Distance, as a method used to limit operator exposure, means that: - ANS>> the operator should maximize the distance from the source during an exposure. Shielding worn for personnel protection is designed to attenuate what source of exposure - ANS>> scatter radiation Which of the following is an acronym for a common type of personnel dosimeter - ANS>> TLD What is the recommended placement for a personnel dosimeter on the body of the limited operator - ANS>> The badge should be worn in the region of the collar on the anterior surface of the body and outside the lead apron if worn. What is the NCRP recommended annual effective dose limit for occupational exposure
- ANS>> 5.0 rem (0.05 severt) What is the NCRP recommended monthly effective (or equivalent) dose limit to the fetus for a prego worker? - ANS>> 0.05 rem (0.0005 Sv) Radiation monitoring of personnel is required when what percentage of the annual occupational effective dose limit is likely to be received - ANS>> 10% What is the conventional (British system) radiation unit to express radiation intensity in air? - ANS>> Roentgen The conventional unit commonly used to report occupational dose to radiation workers in the U.S. is the: - ANS>> rem What is the conventional (British system) radiation unit of absorbed dose - ANS>> Rad According to the Bergonie Tribondeau law, which of the following types of cells are most radiosensitive? - ANS>> Embryonic tissue cells Which type of x-ray photon interaction with the body is primarily responsible for the radiation dose absorbed by the pt? - ANS>> Photoelectric
The target of the x-ray tube is made of: - ANS>> Tungsten What is the standard control limit for the field light to radiation field alignment test - ANS>> +- 2% SID What is the standard control limit for the beam (central ray) alignment test? - ANS>> within 1 degree of perpendicular How often should lead aprons and gloves be checked for cracks or holes - ANS>> every 6 months How can detector fog be prevented when using computed radiography cassettes - ANS>> protect the cassette before and after exposure Which of the following will result in increased radiographic density - ANS>> Increased: mA, exposure time, and kVp If the radiographic image is overexposed, which of the following changes in exposure factors should be used to correct the problem - ANS>> Decrease the mAs The relationship between SID and beam intensity is expressed in the: - ANS>> Inverse square law What are the four primary factors of radiographic quality (photographic and geometric properties)? - ANS>> Density Contrast Distortion Recorded detail Contrast is primarily controlled by altering the: - ANS>> kVp Scatter radiation fog affects radiographic quality by causing - ANS>> decreasing contrast A change from small focal spot to the large focal spot will result in: - ANS>> decreased image sharpness/detail An increase in object image receptor distance (OID) will result in: - ANS>> Increased magnification Motion of the patient, the tube, or the IR during the exposure will result in decreased: - ANS>> recorded detail What does quantum mottle (noise) look like on a radiographic image? - ANS>> finely speckled or grainy areas
Quantum mottle with a digital imaging system is caused by: - ANS>> the mAs being set too low Which of the following will increase recorded detail? - ANS>> *increase in SID *Decrease in focal spot size What is the appearance of a high signal to noise ratio image - ANS>> highly detailed, with very little quantum mottle What is the proper method for storing unopened boxes of x-ray film - ANS>> standing on edge Which of the following describe the action of the developer in an automatic film processor? - ANS>> changes the exposed silver halide crystals into black, metallic silver During digital image processing, electronic collimation (masking) should not be used to replace: - ANS>> Proper radiographic collimation Which of the following is not a component of a computed radiography plate reader? - ANS>> Developing Solution What conditions are most important for optimum viewing of radiographic images? - ANS>> low room light level Marks, exposures, or images on a radiograph that are not a part of the intended image are called: - ANS>> artifacts If the amount of irradiated tissue increases, what happens to scatter radiation fog? - ANS>> scatter radiation fog increases The most affective and practical way to reduce scatter radiation fog on a radiograph is to: - ANS>> use a grid or bucky As a general rule, a grid should be employed when the part thickness is greater than: - ANS>> 12cm Technique charts are based on patient part measurements obtained using an x-ray caliper and are expressed as: - ANS>> Thickness in centimeters Which of the following pathologic conditions would require a decrease in exposure - ANS>> 1. Multiple myeloma
- Emphysema
- Osteoporosis
Which of the following is not a form of nonverbal communication? - ANS>> speaking Mrs. Elizabeth Dunbar is 86 years old and a bit confused. She is most likely to respond appropriately if you address her as: - ANS>> Mrs. Dunbar Which of the following are correct statements of proper body mechanics? - ANS>> 1. Use a broad stance
- Carry heavy objects close to your body What type of disease transmission is possible when the limited operator does not clean the bucky device after performing an examination on a patient with influenza? - ANS>> Indirect contact or fomite transmission Standard precautions involve the use of barriers whenever contact is anticipated with: - ANS>> 1. blood
- Body fluids
- Mucous membranes The process of reducing the probability that infectious organisms will be transmitted to a susceptible individual is called: - ANS>> Asepsis A health care workers single best protection against disease is: - ANS>> frequent hand washing A limited operator who does not change linens between patients is: - ANS>> providing an opportunity for famite What is anaphylaxis? - ANS>> A severe allergic reaction What is the basis life support system used to ventilate the lungs and circulate the blood in the event of cardiac or respiratory arrest - ANS>> CPR When a patient in cardiac arrest presents with a rapid, weak, and ineffective heartbeat, what device is used to return the heart to a normal rhythm? - ANS>> AED Which of the following vita signs can be assessed with out touching the patient? - ANS>> Respiration What is the most common site for palpitation of a patients pulse? - ANS>> Radial artery at the wrist When pt is facing the IR for a chest x-ray the x-ray goes through the back & hits the IR to create the image-what is this called? - ANS>> Posterior anterior or PA What structure separates the thoracic cavity from the abdominal cavity? - ANS>> The diaphragm
Which of the following organs are found within the mediastinum? - ANS>> Heart & Trachea Three lobes are present in which lungs? - ANS>> Right lung What is the name of the upper portion of the lung? - ANS>> Apex The inferior lateral corners of the lungs, visible on a PA chest radiograph, are called the: - ANS>> castophrenic angles When taking a PA projection of the chest the recommended source image receptor distance (SID) is: - ANS>> 72 inches What is the purpose of the 72in SID used for chest radiography? - ANS>> Minimize magnification of the heart shadow Which of the following describe the importance of using an upright position for chest radiography? - ANS>> 1. The upright position demonstrates air-fluid levels
- The upright position allows maximum lung expansion.
- The upright position minimizes magnification of the heart. In chest radiography, which body habitus is best imaged by placing the 14x17 in image receptor crosswise in the upright grid cabinet? - ANS>> Hypersthenic Which of the following techniques is desirable for chest radiography? - ANS>> High kilovoltage (kVp) high milliamperage (mA) and short exposure time What is the purpose of rotating the patients shoulders anteriorly for the PA projection of the chest? - ANS>> This motion rotates the scapulae out of the lungs Where does the central ray enter the patient for the upright, PA projection of the chest?
- ANS>> Midsagital plane at the level of T- 7 What is the proper placement of the arms for the upright lateral projection of the chest?
- ANS>> Arms raised over the head with the hands grasping opposite elbows What are the proper patient instructions for the PA projection of the chest? - ANS>> stop breathing after the second deep inspiration Lateral projection of the chest are taken with the left side against the IR because: - ANS>> magnification of the cardiac silhouette is reduced with the left side nearer the IR
What change in technical factors is required when an ankle is a dry plaster cast must be radiographed? - ANS>> Increase milliampere seconds (mAs) by two times The bones that are located in the palm of the hand are called? - ANS>> metacarpals The bones of the forearm are the: - ANS>> Radius and Ulna Where is the humerus located - ANS>> In the upper portion of the arm Which surface of the hand should be in contact with the IR for the posteroanterior (PA) projection? - ANS>> Anterior (palmar) What is the central point of the central ray for the PA projection of the hand - ANS>> Third metacarpophalangeal joint Which surface of the hand should be in contact with the IR for the lateral projection of the fifth digit (pinky)? - ANS>> The medial surface What is the position of the wrist for the PA oblique projection in lateral rotation? - ANS>> Coronal plane of the wrist at a 45 degree angle to the IR with the anteromedial surface on the IR What is the proper patient position for the AP projection of the forearm? - ANS>> elbow extended, wrist and elbow parallel to the IR, hand supinated Which of the following describes the proper method for positioning the humerus for an AP projection? - ANS>> upper limb adducted, elbow extended, humeral epicondyles parallel to the IR What specific anatomy is demonstrated w/o superimposition in the AP oblique projection in 45 degree lateral rotation? - ANS>> Radial head and capitulm What change is technical factors is required when a wrist in a fiberglass cast must be radiographed? - ANS>> No change is required Where is the central ray entrance point for the AP projections of the shoulder? - ANS>> 1 inch medial and inferior to the coracoid process What are the proper patient instructions for the AP projection of the shoulder - ANS>> Stop breathing, and do not move What is the name of the large, rounded, projection that can be felt on the superior lateral surface of the shoulder? - ANS>> Acromion Which of the following cranial bones are paired (right & left)? - ANS>> Parietal & Temporal
What structure serves as the passage way for the spinal cord to exit the skull and pass into the spinal canal of the vertebral column? - ANS>> Foramen Magnum When taking a poserioranterior (PA) axial projection (Caldwell method) of the skull, the central ray is directed: - ANS>> 15 degrees caudad Which radiographic bvaseline is used to position the PA axial projection (Caldwell method) of the cranium? - ANS>> OML (orbital meatal line) Which cranial projection best demonstrates the occipital bone? - ANS>> AP (Anteriorposterior) Axial (Towne method) The patient is in a prone oblique position with the midsagittal plane of the head parallel to the IR and the interpupillary line perpendicular to the IR. The central ray is directed 2 inches superior to EAM-WHAT PROJECTION? - ANS>> Lateral The patient is positioned supine with the midsagittal plane and OML perpendicular to the IR. The central ray is angled 30 degrees caudad and enters the midsagittal plane at approximately 2.5 inches superior to the glabella. What projection will be imaged on the radiograph? - ANS>> AP axial (towne method) What positioning accessory can be used to assist the patient in holding the correct position for an AP axial projection of the skull? - ANS>> A wedge filter r-filled cavities located in some bones of the face and cranium are called: - ANS>> paranasal sinuses Which of the following bones contain paranasal sinuses? - ANS>> Frontal & Ethmoid What is the purpose of performing sinus radiography with the patient in the upright position? - ANS>> To demonstrate air-fluid levels Which paranasal sinuses are best demonstrated in the PA axial projection (Caldwell method)? - ANS>> Frontal & Ethmoid Which of the following projections will demonstrate the sphenoid sinus? - ANS>> Lateral Which projection best demonstrates the maxillary sinuses? - ANS>> Parietoacanthial (Waters method) Which paranasal sinuses are demonstrated by the SMV projection? - ANS>> Sphenoid and Ethmoid
The patient is positioned with the coronal plane of the body perpendicular to the IR, the midsagittal plane parallel to the IR, and the arm closest to the IR raised over the head. The central ray is perpendicular and centered to the level of the C7 to T1 interspace. What projection and anatomy will be demonstrated in this image? - ANS>> A lateral projection of the cervicothoracic region What devices may be used to improve visualization of the spinous processes of the thoracic spine on the lateral projection? - ANS>> A piece of lead placed behind the shadow of the patients back Which structures should be seen on the lateral projection of the thoracic spine? - ANS>> T3 through T What is the number of vertebrae in the normal lumbar spine? - ANS>> 5 Which portion of the spine is made up of five vertebrae and has a lordotic curve? - ANS>> Lumbar When using a 14x17in IR where should the central ray enter the patient for an AP projection of the lumbar spine? - ANS>> At the iliac crest in the midline of the patient When using a 10x12 IR where should the central ray enter the patient for an AP projection of the lumbar spine? - ANS>> At a level 1.5in superior to the iliac crest in the midline of the patient What positioning maneuver is used to improve patient comfort and reduce the lordotic curve of the lumbar spine when positioning a recumbent patient for an AP projection of the lumbar spine? - ANS>> Flexing the knees and using a support under them Which projection of the lumbar spine demonstrates open intervertebral foramina? - ANS>> Lateral Which of the following body positions will demonstrate the left zygapophyseal joints of the lumbar spine? - ANS>> 45 degrees left posterior oblique (LPO) What specific anatomy is best demonstrated on the AP oblique projection of the lumbar spine if the patient is positioned in a 45 degree RPO position? - ANS>> Right Zygapophyseal joints What is the central ray angle and direction for the AP axial projection of the sacrum? - ANS>> 15 degrees cephalad What portion of the spine is commonly called the tailbone? - ANS>> coccyx
Which of the following statements is true regarding spine radiography to evaluate scoliosis - ANS>> The IR should extend from the top of the patients ear to the level of the greater trochanter The bones of the forefoot include the: - ANS>> Phalanges and metatarsals The bones of the midfoot are called the: - ANS>> Tarsals Small, flat, oval bones in the region of the first metatarsophalangeal (MTP) joint are called the: - ANS>> Sesamoid bones What tarsal is commonly referred to as the "heel bone"? - ANS>> Calcaneus Which of the following bones are tarsal bones? - ANS>> Cuneiform & Cuboid When taking an anteroposterior (AP) axial projection of the foot, the central ray is directed: - ANS>> 10 degrees toward the heel Where does the central ray enter the patient for the AP axial projection of the foot - ANS>> At the base of the third metatarsal Which surface of the foot should be in contact with the IR for the recumbent lateral projection of the foot? - ANS>> Lateral Which of the following is true regarding the lateral projection of the foot? - ANS>> The ankle should be dorsiflexed so that the long axis of the foot is perpendicular to the tibia How much is the plantar surface of the foot elevated from the IR for the AP oblique projection of the foot? - ANS>> 30 degrees Which foot projection and position will demonstrate the metatarsals (third through fifth) without superimposition? - ANS>> AP oblique projection in 30 degree medial rotation Which foot projection and position will demonstrate the medial and intermediate cuneiforms without superimposition? - ANS>> AP oblique projection in 30 degree lateral rotation Which foot projection and position will demonstrate the cuboid, navicular, and lateral cuneiforms, without superimposition? - ANS>> AP oblique projection in 30 degree medial rotation Which foot projection and position will demonstrate the entire foot in near anatomic position? - ANS>> AP axial projection with the plantar surface of the foot in contact with the IR What is the name given to the distal end of the fibula? - ANS>> Lateral malleolus
