Final 1f

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Intravascular contrast material is used in most CT scans of the abdomen and pelvis. A) True B) False

Split-bolus injections divide the contrast media dose into two bolus injections with a delay of how much time between injections?

2-15 mins

The SUV of the liver should be in what range?

2-2.5

Children interact at a close distance, whereas adults interact at a farther distance. A) True B) False

Conventional radiography barium suspension cannot be used in CT. A) True B) False

The development of computed tomographic angiography and 3D imaging has not proved effective in the evaluation of cerebral aneurysms and arteriovenous malformations.

False

True or False. CT workstation computers are classified as supercomputers for their processing capabilities and size.

False

True or False. Determining tissue types in CT slices is referred to as volume formation.

False

True or False. LAN networks connect computers separated by large distances.

False

True or False. Linearity can be checked by a yearly calibration test.

False

True or False. Studies have shown that virtual endoscopies would be more expensive than real endoscopies.

False

True or False. The number of bits per pixel is the bit formation.

False

True or False. The photoelectric effect occurs mainly in tissues with a low atomic number.

False

True or False: The customer driven management model will work only for the radiology department

False

True or False: The original term used to describe imaging of a specific layer or section of the body was transverse axial tomography.

False

True or False? For CT scans of the abdomen, most indications do not require the administration of either oral or intravenous contrast media.

False

True or False? It is always necessary to ask the patient to suspend breathing for CT studies of the head or neck.

False

True or False? The American Heart Association reports that cerebrovascular disorders such as ischemic and hemorrhagic strokes are the most frequent cause of death in North America.

False

True or False? Thoracic scans done for the screening, detection, or exclusion of pulmonary nodules or primary lung diseases such as emphysema or fibrosis are typically done with IV contrast administration.

False

True or false : standard deviation alone is sufficient to fully characterize the noise in the image

False

Which of the following reduces the amount of data that makes up the image?

Image compression

Which of the following does the computer system perform?

Image manipulation

Raw data that results from an MDCT scan acquisition is used so that the 1-mm slices aare combined to produce thicker slices for viewing. This is called:

Image reconstruction

If used, when is short-acting nitroglycerin given to the patient?

Immediately before scan initiation

The cetral processing unit (CPU) performs what function?

Interprets computer program instructions and sequences tasks

What is used to measure exposure?

Ionization chamber

X-rays are a form of which of the following kinds of radiation?

Ionizing

Which is the most common type of stroke?

Ischemic

Which type of image compression results in no loss of information in the compressed image data?

Lossless

What method of image compression results in the loss of no information during the compression process?

Lossless compression

Three major sources contribute to the noise in the image. What are they?

Quantum noise by x-ray flux , inherent physical limitations of the system, and reconstruction parameters

What two electronic elements form the radiology information infastructure?

RIS & PACS

Which of the following groups is run by the government of Japan, primarily to study Japanese atomic bomb survivors?

Radiation Effects Research Foundation

In a hospital setting, which of the following professionals is expressly charged by the hospital administration with being directly responsible for the execution, enforcement, and maintenance of the ALARA program?

Radiation Safety Officer

Which is not true about CT angiography?

Rapid, high-resolution scans are taken while contrast is in the venous enhancement phase.

All the thousands of bits of data acquired by the CT system with each scan is called

Raw data

true

True or false? Sinus screening is intended as an inexpensive, accurate and low radiation dose method for confirming the presence of inflammatory sinonasal disease

Slices that are produced by repeatedly scanning the same region at the same table position is referred to as ___________mode.

cine

The practice of grouping more than one axial scan in a single breath-hold is often referred to as

clustering

Cables made up of twisted pairs of copper wire are called___cables.

ethernet

True or False? Airway imaging is routinely performed at expiration only.

false

True or False? Most renal abnormalities are best seen on CT without IV contrast medium administration

false

When LET increases, the chance of producing a significant biologic response in the radiosensitive DNA macromolecule

grows

by exclusively using intermittent fluoroscopy

how can dose rates be minimized when CTF is used?

by exclusively using intermittent fluoroscopy

how can dose rates by minimized when CTF is used

the patient is positioned supine on the CT table with the arm to be examined downward alongside the body and the opposite arm extended over the patients head

how is the patient positioned for a CT arthrography of the shoulder?

the patient lies supine on the scanner table with legs extended, knees side by side, and enters the scanner feet first

how is the patient positioned for a CT of the knee?

from 4-6 hours

how many hours is a patient required to fast before a PET examination?

60 times

how many times more common are adrenal masses that are benign cortical adenomas than those that are primary adrenal cortical carcinomas?

1-3 hours

how much of a time delay if recommended when CT is performed after intrathecal contrast administration for fluoroscopic myelography?

_________ strokes occur within the brain parenchyma itself, and a hematoma often results.

intracerebral hemorrhagic

Visible images include all of the following except:

mathematical images.

the ability to observe low-contrast objects whose density is slightly different from the background

sensitivity

another name for prospective ECG triggering

sequential/cine-mode scanning

Computers that act on requests from other networked computers, rather than froma person imputting directly into it, are called

servers

The purpose of the imaging system is to perform all of the following except:

store images for retrieval.

motion of any variety will manifest itself on a CT image as ____ artifacts

streak

Both voluntary and involuntary motion appears as ____________ that are usually tangential to the high-contrast edges of the moving part.

streaks

What is the term used to describe a time-limited event in which the neurologic deficits occur in a progressive pattern.

stroke in evolution

when talking about subject contrast in radiography there are two major contributing factors

subject contrast and film contrast

what drug is sometimes given before cardiac CT and what does it do?

sublingual nitroglycerin; it dilates vessels and improves visualization

Regarding exposure to ionizing radiation, patients who are educated to understand the medical benefit of an imaging procedure are more likely to

suppress any radiation phobia and be willing to assume a small chance of possible biologic damage.

why are prone images sometimes used for thoracic images?

to differentiate actual disease from densities related to effects of gravity that mimic disease

why is contrast used in thoracic studies?

to differentiate vascular and nonvascular structures

The purpose of image enhancement is:

to generate an image more pleasing to the observer.

Which is a disadvantage to workstation created MPR's?

to produce the highest quality MPR's the thinnest slices must be sent to the workstation. This amount of data can slow down the PACS.

The geometric arrangement of a computer system is referred to as its ___

topology

True or False: Partial volume artifacts can occur even with thin-slice acquisition if special attention is not paid to other accessories.

true

True or False? CT of the abdomen and pelvis is used for the evaluation of virtually all organs and most vessels.

true

True or False? For abdominopelvic scanning, patients are asked to hold their breath during data acquisition

true

True or False? HRCT protocols are routinely obtained at full inspiration.

true

false

true or false? CT and CT fluoroscopy (CTF) must be used separately and cannot be used in combination

false

true or false? CT and magnetic resonance imaging (MRI) has a high sensitivity for the detection of obvious structural disruption and is useful in characterizing these abnormalities as malignant or benign

true

true or false? CT data acquisition of the foot and ankle can be obtained in a number different imaging planes?

false

true or false? CT fluoroscopy (CTF) allows for the near real time capabilities of traditional fluoroscopy but does not provide the superior contrast resolution of CT

false

true or false? CT fluoroscopy (CTF) allows for the near real-time capabilities of traditional fluoroscopy but does not provide the superior contrast resolution of CT

true

true or false? CT fluoroscopy (CTF) capabilities are not standard on scanners

true

true or false? CT of the musculoskeletal system has the ability to image both sides of the body

false

true or false? CT of the spine is most often performed with IV contrast media administration

false

true or false? CT scans of the brain are always done with IV contrast enhancement.

true

true or false? PET may demonstrate pathologic changes long before they would be revealed by modalities like CT or MRI

false

true or false? a CT scan of the left knee is shown in the image. the region represented by number 1 is the fibula

true

true or false? along with magnetic resonance imaging (MRI), CT is a major method for the evaluation of musculoskeletal anatomy and disease

true

true or false? because of the dense bone of the skull, beam-hardening artifact is common in the posterior fossa

false

true or false? decreased glucose use is frequently associated with malignancies

true

true or false? for a CT scan of the foot, it is common practice for the technologist to include a radiopaque marker to aid in identification of the scan orientation

true

true or false? for abdominopelvic scanning, patients are asked to hold their breath during data acquisition?

true

true or false? improvements in the design of the CT systems allow successful imaging of the total joint prosthesis and the soft tissues around them

false

true or false? in general, when scanning long bones, the plane of the CT section should be parallel to the long axis

true

true or false? intravenous contrast media is not routinely administered for musculoskeletal trauma

true

true or false? intravenous contrast medium is not routinely administered for musculoskeletal trauma?

false

true or false? it is always necessary to ask the patient to suspend breathing for CT studies of the head and neck

false

true or false? most renal abnormalities are best seen on CT without IV contrast medium administration

true

true or false? most thoracic protocols are performed while the patient lies in a supine position on the scan table with the arms elevated above the head

false

true or false? scans of the lower extremities are usually scanned with the patient supine and placed head first into the scanner

false

true or false? the American heart association reports that cerebrovascular disorders such as ischemic and hemorrhagic strokes are the most frequent cause of death in north America?

true

true or false? the location and extent of the ischemic lesion, combined with the severity of blood flow restriction, are the main factors that predict outcome in the treatment of stroke

true

true or false? the responsibilities of a PET/CT technologist combine the responsibilities of a nuclear medicine and CT technologist, yet technologists are very rarely trained in both modalities

true

true or false? the responsibilities of the PET/CT technologist combine the responsibilities of a nuclear medicine and CT technologist, yet tech are very rarely trained in both modalities

false

true or false? the timing of an insulin injection does not generally affect a PET scan?

If two anatomic structures have the same density and atomic number but one is twice as thick as the other, the thicker structure will absorb

twice as many x-ray photons

head and neck cancer or lymphoma

when muscle uptake if focal and unilateral interpretation is especially more difficult in patients who have which of the following?

head and neck cancer or lymphoma

when muscle uptake is focal and unilateral interpretation is especially more difficult in patients who have which of the following?

the study is done without IV contrast enhancement and scanning is done in the coronal plane

when sinus screening is done for chronic sinusitis, which of the following is true

glucocorticoids

which are secreted by the middle region of the adrenal cortex?

X-Y

which axis does the computer start printing the design?

areas that have been treated with radiotherapy

which causes a decrease in FDG uptake?

right ventricle

which cavity of the heart sends blood only to the lungs?

an individual with her arms along her side with the palms of her hands facing outward

which characterizes classic "anatomic position"

lesions with values greater than 2.5 have been shown to have a likelihood of malignancy, whereas lesions with values less than 2 are usually benign

which correctly describes how the SUV correlates with the malignant potential of a lesion?

lesions with values greater than 2.5 have been shown to have likelihood of malignancy, whereas lesions with values less than 2 are usually benign

which correctly describes how the SUV correlates with the malignant potential of a lesion?

arteries or veins taken from elsewhere in the patients body are grafted from the aorta to the coronary arteries to bypass atherosclerotic narrowings and improve the blood supply to the coronary circulation supplying the myocardium

which describes CABG?

teeth grinding

which does not cause asymmetry in the salivary gland during FDG imaging?

SUV = radioactivity concentration in ROI / (injection dose (Bq) / patient weight (g))

which formula can be used to calculate SUV?

aortic

which heart valve is in the right side of the heart, between the left ventricle and the entrance to the aorta?

PET

which imaging structure creates images of the body's physiological functions, such as blood flow and metabolism?

the procedure can be lengthy

which is a drawback to using sequential CT scanning for intervention procedures?

window width approximately 2000; window level approximately 600

which is a typical bone window setting

window width approximately 450; window level approximately 50

which is a typical soft tissue window setting?

gas

which is not a high density material

gas

which is not a high-density material?

lungs

which is not a location where normal physiological accumulation of FDG occurs?

C shape

which is not a possible shape of the adrenal glands on a cross sectional image?

menstruation

which is not a reason for increased uptake in the breast?

rapid, high resolution scans are taken while contrast is in the venous enhancement phase

which is not true about CT angiography?

the patients wrist as it rests on his abdomen

which is the least favorite choice for positioning a patient during a CT examination of the wrist?

extending the patients arm over their head

which is the most common patient position for CT examinations of the wrist?

ischemic

which is the most common type of stroke

hyperventilation

which may induce uptake in the diaphragm?

false negative rate

which of the following is NOT a potential harm of having a low dose lung scan:

after chemotherapy, there is increased uptake as a result of bone marrow recovery that usually resolves 1 month after recovery

which of the following statements is true?

in general, higher accumulations of FDG usually correlate with more aggressive tumors and a greater number of viable tumor cells

which of the following statements is true?

creation of customized prosthetics, implants and anatomical models, tissue and organ fabrication

which of the following technologies are actively being developed with 3D bioprinting?

creation of customized prosthetics, tissue and organ fabrication, implants and anatomical models

which of the following technologies are actively being developed with 3D bioprinting?

printing stem cells

which of the following was not listed as a future use of 3D printing?

it is not useful for evaluation of the joint capsule and intrascapular structures

which statement about CT arthrography of the shoulder is not true?

because of radiation dose concerns, patients are limited to a single position during the procedure

which statement about CT interventional procedures is not true?

because of radiation dose concerns, patients are limited to a single positron during the procedure

which statement about CT interventional procedures is not true?

it allows the acquisition of slices as thin as 0.2 mm

which statement about multidetector row CT (MDCT) is not true?

intravenous contrast media is routinely administered for musculoskeletal trauma

which statement about musculoskeletal protocols is not true?

it has relatively poor contrast sensitivity

which statement about musculoskeletal scanning is not true?

it should be one of the last arteries to enhance

which statement is not true about the reference artery chosen during the post processing of CT perfusion scans?

TIAs are an irreversible episode of focal neurologic dysfunction

which statement is not true about transient ischemic attacks (TIA's)?

TIAs are an irreversible episode of focal neurologic dysfunction

which statement is not true about transient ischemic attacks (TIAs)?

hypertension

which stroke factors contribute to 70% of all strokes?

hypertension

which stroke risk factor contributes to 70% of all strokes?

SLS

which type of printing method involves using a laser to draw the shape of the object in powder and fuses the powder into solid form?

TIJ

which type of printing method involves using bioink?

FDM

which type of printing method is the cheapest and most common?

subarachnoid hemorrhage

which type of stroke is usually caused by the rupture of an aneurysm

thrombotic

which type of stroke occurs when a clot that forms as a result of atherosclerosis blocks an artery that supplies blood to the brain

lacunar stroke

which type of stroke occurs when a small artery, such as those that supply the deep cerebral white matter is blocked

there is radiation exposure to the abdomen

why is positioning the patient's wrist on his abdomen for the a CT wrist examination the least desirable patient position?

What determines the center pixel value in gray scale?

window level

What determines which Hounsfield values are displayed as shades of gray?

window level

What determines the number of Hounsfield units assigned to each level of gray in a gray-scale image?

window width

Tumors and other disease processes always have different attenuation coefficients than those of their surrounding tissue. A) True B) False

WANs typically use Ethernet connections to attach computers to the network. A) True B) False

What barrier to communication has likely occurred when nonverbal messages are ignored? A) Language B) Misreading of body language, tone, and other non-verbal forms of communication C) Power struggles D) Fuzzy transmission

A PET study's sensitivity could be limited if the patient's blood sugar level is more than how many mg/dL before the injection? a. 100 mg/dL b. 120 mg/dL c. 180 mg/dL d. 200 mg/dL

About how many times greater is radiation exposure from a whole body CT scan than from a chest x-ray? a. 5 times greater b. 10 times greater c. 100 times greater d. 1000 times greater

Which type of stroke is usually caused by the rupture of an aneurysm? a. lacunar stroke b. hypotensive c. subarachnoid hemorrhagic d. thrombotic

Which types of reaction appear account for the majority of true late reactions? A) dizziness B) headaches C) skin reactions D) gastrointestinal disturbances

If an image reproduced the object exactly, what is the MTF of the system?

Artifacts that result from undersampling are called

Alisaing artifacts

The CT number is related to the ____ _____ of the object

Attenuation coefficient

What is tube current?

The product of milliampere setting and scan time

An object slightly less dense than water. What is the exoected Hounsfield measurement?

-10

A protective curtain, or sliding panel, with a minimum of 0.25-mm lead equivalent, should normally be positioned between the fluoroscopist and the patient to intercept which of the following types of radiation? -Primary radiation -Scattered radiation above the tabletop -Exit or image-formation radiation -Direct radiation

-Scattered radiation above the tabletop

An MTF of ____ indicates no transfer of object to image

If the window width is 500 and the range of Hounsfield numbers to be included in the gray scale is 250 to 250, what is the window level?

Based on current data, which of the following would be considered a safe radiation dose for the gonads of both males and females?

0 Gyt

In general, laboratory experiments with mice prove that cataracts may be induced with doses of ionizing radiation as low as

0.1 Gyt.

CT is capable of detecting density differences as low as

0.25 - 0.5%

Epidemiologic studies of atomic bomb survivors exposed in utero have provided conclusive evidence of a dose-dependent increase in the incidence of severe intellectual disability for fetal doses greater than approximately

0.4 Sv.

The DFOV used for a study is 30 cm and a 512 matrix is used. What is the approximate pixel size in mm?

0.59 mm

When doors to radiographic and fluoroscopic rooms are closed during radiation exposures, a substantial degree of protection is provided for persons in areas adjacent to the room door. This is because in most facilities room doors have attenuation for diagnostic energy x-ray equivalent to that provided by _______ mm of lead. 0.2 0.4 0.6 0.8

0.8

A scanner allows mA choices in 20-mA increments from 20 to 700, and offers a choice of scan times from 0.4, 0.6, 0.8, 1.0, and 2.0 seconds. Which combination of mA and scan time will produce an mAs of 336?

0.8 second and 420 mA

An MTF of ___ means the imaging system has reproduced the object exactly (100% transfer of information)

Which of the following may occur if the patient's arms are by their sides during a chest CT exam if the scan field-of-view is 33cm? 1. beam hardening 2. out-of-field artifact 3. cone beam artifact

1 & 2

Which of the following statements is TRUE: 1. kV is the voltage potential between the tube cathode and anode while mA ultimately controls the filament current and ,thus, the temperature of the cathode. 2. kV controls the energy level of the X-ray photons and mA controls the number X-ray photons emitted from the tube 3. Although the kV and mA affect the operation of the CT X-ray tube, the parameters have no bearing on the image quality

1 & 2

Currently, evidence of radiation-induced hereditary effects has not been observed in persons employed in diagnostic imaging or in persons undergoing radiologic examinations. Even with this information, it is still recommended that 1. gonadal shielding be effectively used. 2. all radiation exposure be maintained as low as reasonably achievable (ALARA). 3. alternative procedures be substituted for x-ray procedures whenever diagnostic information must be obtained.

1 and 2 only

Which of the following is/are considered low-LET radiation(s)? 1. X-rays 2. Alpha particles 3. Gamma rays

1 and 3 only

Which of the following units of measure are not SI units? 1. Roentgens 2. Coulombs per kilogram, grays, sieverts 3. Rads and rems

1 and 3 only

In which of the following human populations is the risk for causing a radiation-induced cancer not directly measurable? 1. All patients in diagnostic radiology subjected to a radiation dose below 0.1 Sv 2. Chernobyl radiation accident victims living in contaminated villages 3. Atomic bomb survivors

1 only

How much of a time delay is recommended when CT is performed after intrathecal contrast administration for fluoroscopic myelography?

1 to 3 hours

When a beam of X-rays passes through the patient, the relative transmission or penetration measurement can be calculated by using which of the following? 1) Log of the ratio of intensity of X-rays at the source to the intensity of the detector 2) Log of the ratio of the detector intensity to the source intensity 3) Ratio of the source intensity to the detector intensity 4) Ratio of the detector intensity to the source intensity

1) Log of the ratio of intensity of x-rays at the source to the intensity of the detector

A CT image of 12 bits per pixel means: 1) each pixel can have a total of 4096 shades of gray. 2) the matrix is 4096 X 4096. 3) the pixel size is 12 mm. 4) the voxel size is 12 mm.

1) each pixel can have a total of 4096 shades of gray

What is the unit of the CTDI? 1)gray 2)Roentgen 3)rem 4)seivert

1)gray

___________ in the image is a possible manifestation of patient motion. 1. ghosting 2. blurring 3. streaks

1, 2 & 3

Which of the following affects the severity of metal artifacts? 1. the quantity, composition and shape of the metal 2. the slice thickness 3. the number of data smapling points

1, 2, & 3

Diagnostic efficacy includes 1. determining if an imaging procedure is justified. 2. obtaining images with minimal radiation exposure. 3. adhering to radiation safety guidelines. 4. revealing the presence or absence of disease in a patient.

1, 2, 3, and 4

Which of the following are required by The Joint Commission for CT? 1. Annual education of staff in dose reduction techniques 2. Minimum qualifications for medical physicists 3. Documentation of CT radiation doses 4. Management of CT protocols to minimize radiation dose

1, 2, 3, and 4

In general, which of the following can human cells do? 1. Move, grow, react, and protect themselves 2. Repair damage and regulate life processes 3. Reproduce

1, 2, and 3

Some local tissues suffer immediate consequences from high radiation doses. Examples of such tissues include 1. bone marrow. 2. male and female reproductive organs. 3. skin.

1, 2, and 3

Upper boundary radiation exposure limits for occupationally exposed persons are associated with risks that are similar to those encountered by employees in other industries that are generally considered to be reasonably safe. These industries include 1. manufacturing. 2. trade. 3. government.

1, 2, and 3

Which of the following are considered to be benefits of an aggressive repeat analysis program? 1. Increased awareness among staff and student radiographers of the need to produce optimal quality recorded images from the start. 2. Radiographers become more careful in producing radiographic images because they are aware that images are being reviewed. 3. When the repeat analysis program identifies problems or concerns, in-service education programs covering these specific topics may be designed for imaging personnel.

1, 2, and 3

Which of the following are functions and/or responsibilities of the United States Occupational Safety and Health Administration (OSHA)? 1. Functions as a monitoring agency in places of employment, predominantly in industry 2. Regulates occupational exposure to radiation through Part 1910 of Title 29 of the U.S. Code of Federal Regulations (29 CFR 1910) 3. Responsible for regulations concerning an employee's "right to know" with regard to hazards in the workplace

1, 2, and 3

Which of the following x-ray procedures increases the radiographer's risk of exposure to ionizing radiation compared to radiography? 1. Mobile C-arm fluoroscopy 2. Interventional procedures that use high level control fluoroscopy 3. Mobile radiographic examinations

1, 2, and 3

Working in conjunction with their partners in other agencies, the FDA intends to take action to 1. promote safe use of medical imaging devices. 2. support informed clinical decision. 3. increase patient awareness.

1, 2, and 3

Which of the following are early tissue reactions of ionizing radiation that were experienced by early radiation workers? 1. Diffuse redness of skin 2. Blood disorders 3. Organ atrophy 4. Intestinal disorders

1, 2, and 4 only

How many pixels are contained in a 1,024 matrix image?

1,048,576

A variation in which of the following will affect the hardening of the x-ray beam? 1. tissue density 2. tissue thickness 3. kVp

1,2 & 3

Which of the following affects beam hardening? 1. the types of tissues the beam passes through 2. the thickness of the tissues traversed by the beam 3. the energies of photons in the beam

1,2 & 3

Which of the following is TRUE regarding ring artifacts? 1. they are more likely to occur on the 3rd generation scanner 2. they can occur as a rsult of a faulty detector element 3. they are rarely seen on 4th generation scanners

1,2 & 3

Which of the following would make noise less noticeable in an image? 1. increased window width 2. increased mAs 3. increased slice thickness

1,2 &3

Analysis of an imaging department's repeats rate 1. provides valuable information for process improvement. 2. helps minimize patient exposure. 3. improves overall performance of the department.

1,2,3

Data acquisition refers to: A. collecting X-ray transmission readings from the patient. B. subjecting data to computer processing. C. changing the data before they are displayed on a monitor. D. storing the data collected from the patient onto magnetic tapes or disks.

1. Collecting X-ray transmission readings from the patient

In CT, A. a computer is used to reconstruct images of sectional anatomy. B. a computer is used to calculate radiation dose to the patient. C. a computer is not required because the physicist calculates the image, which the computer then prints out. D. special detectors are used to reconstruct sectional images.

1. a computer is used to reconstruct images of sectional anatomy.

The x-ray photon energy required to initiate pair production is

1.022 MeV.

What is the typical slice thickness for studies of the head?

1.25 mm

Which is the pitch in the following scenario: 16 slice scanner, 0.5mm slice thickness, table movement of 12mm per rotation?

1.5

The SUV of the mediastinal blood pool should be in what range?

1.5-2

The DFOV used for an abdominal study is 42 cm and a 256 matrix is used. What is the approximate pixel size in mm?

1.64 mm

Pheochromocytoma are malignant in about what percent of cases?

10 percent

What percent of urinary calculi is thought to pass spontaneously?

10 to 15%

About what percent of the general population has a ramus intermedius artery?

10%

As a general rule, the human eye cannot appreciate contrast differences of less than about what percent?

10%

Film-screen radiography can only detect density differences as low as

10%

Pheochromocytoma are malignant in about what percent of cases?

10%

What percent of urinary calculi is thought to pass spontaneously?

10-15%

Which is a typical injection protocol for a routine contrast examination of the brain?

100 mL delivered at 1 mL/s, scan delay of 5 minutes

Since the density of air is approximately _________________ than that of soft tissue, a given volume of air will interact with far fewer x-ray photons than adjacent regions of soft tissue, thereby permitting more radiation to reach the image receptor.

1000 times smaller

What is the kVp range for routine body CT for adult patients?

120 kVP to 140 kVp

After the intravenous (IV) administration of a bolus of contrast material, when does the hepatic arterial phase typically occur?

15 - 25 seconds after the contrast bolus

After the intravenous (IV) administration of a bolus of contrast material, when does the hepatic arterial phase typically occur?

15 to 25 seconds after the contrast bolus

What percent reduction in radiation dose do automatic tube current modulations provide without degrading image quality?

15% to 40%

Among physicians, cancer deaths attributed to x-ray exposure were reported as early as

1910

The service engineer should be notified about which of the following? 1. frequent bad streaks on the inferior slices of the head scans 2. a consistent circle on the images 3. frequent bad streaks throughout the entire image

2 & 3

A periodic blood count is not recommended as a method for monitoring occupational radiation exposure because 1. biologic damage from ionizing radiation cannot be determined from a blood test. 2. biologic damage has already been sustained when an irregularity is seen in the blood count. 3. a traditional blood count is a relatively insensitive test that is unable to indicate exposures of less than 10 cGy.

2 and 3 only

Which of the following are responsibilities of a health care facility's radiation safety committee (RSC)? 1. Delegate operational funds in the budget for the radiation safety program 2. Provide guidance for the radiation safety program 3. Facilitate the ongoing operation of the radiation safety program

2 and 3 only

Bremsstrahlung radiation does NOT include which type of electron activity? 1. collision between an incoming electron and the nucleus of the target atom. 2. collision between an incoming elecron and an electron in the inner shell of the taret atom. 3. slowing down of an incoming electron due to the effect of passing close to the positive charge of the nucleus of the target atom.

2 only

If an algorithm to correct for the cupping artifact is applied too aggressively to the data for the head image, the __________ of the image would be too bright. 1. top & bottom 2. center 3. edges

2 only

The CT x-ray tube rotates around the patient to: 1. keep the tube cool 2. generate projection views at the different angles 3. minimize the x-ray dose administered to the patient

2 only

Which of the following would increase the severity of the edge gradient effect? 1. a scanner with a small detector aperature 2. a scanner with a low data smapling rate 3. using thin slices

2 only

X-rays are produced whenever fast moving electrons collide with any form of matter because: 1. The electron splits into two X-ray photons of equal energy upon impact with the matter. 2. The electron loses kinetic energy which is converted into the emission of an X-ray photon. 3. The electron converts the electron it collides with into an X-ray photon

2 only

Split-bolus injections divide the contrast media dose into two bolus injections with a delay of how much time between injections?

2 to 15 minutes

The overall complication rate for a fine-needle biopsy is approximately what percent?

A high-kilovolt (kV) technique is necessary in CT imaging for all of the following reasons except: 1) to reduce the contrast of bone relative to soft tissues. 2) to increase the probability of beam hardening. 3) to reduce the dependence of attenuation coefficients on photon energy. 4) to produce a high-radiation flux at the detector.

2) To increase the probability of beam hardening

What is/are the unit(s) of absorbed dose? 1)Roentgen (R) 2)Gray (Gy) 3)Sievert (Sv) 4)rem

2)Gray (Gy)

Which classification of factors has a direct influence on image quality but no direct effect on radiation dose in CT? 1)Direct 2)Indirect 3)Proportional 4)Nonproportional

2)Indirect

About what percent of stroke victims do not survive?

20-30%

A PET study's sensitivity could be limited if the patient's blood sugar level is more than how many mg/dL before the injection of FDG?

200 mg/dL

What is the lifetime rate of appendectomy for women if incidental appendectomies are included?

25 %

Lacunar stroke accounts for _______% of all strokes.

25%

What is the lifetime rate of appendectomy for women if incidental appendectomies are included?

25%

How many shades of gray can the monitor display?

256

How many pixels make up a CT image whose matrix size is 512 X 512?

262,144

An intercranial hemorrhage can be generally be expected to appear hyperdense from onset to _____ days.

To be effective, tissue plasminogen activator (t-PA) must be administered within how many hours of the first signs of stroke?

Beam hardening refers to: 1. the increase in the number of photons reaching the detectors 2. the increase in the number of low energy photons reaching the detectors 3. the increase in the average energy of the photons that reach the detectors

3 only

Which of the following does NOT affect the quantity of the X-rays that completely penetrates the patient? 1. the distance that the X-ray photons must travel on their course through the patient's body 2. the molecular composition of the tissues through which the X-ray photons pass 3. the type of detector material used

3 only

Why must we choose a scan field of view which is larger than the anatomy to be scanned? 1. to achieve the highest spatial resolution 2. to minimize partial volume artifacts 3. to avoid out-of-field artifacts

3 only

Iterative reconstruction algorithms have proven beneficial in dose reduction in each of these CT exams except: 1)pediatric studies. 2)abdominal examinations. 3)brain perfusion imaging. 4)CT angiography.

3)brain perfusion imaging.

Effective mAs can be described as: 1)effective mAs = kilovolts/pitch. 2)effective mAs = true mAs + pitch. 3)effective mAs = true mAs/pitch. 4)effective mAs = pitch/kilovolts.

3)effective mAs = true mAs/pitch.

Approximately how long after the intravenous FDG injection is placed on the examination table?

30-60 mins

If 30 lines can be seen in a 1-cm section in an image of a line pairs phantom, what is the spatial resolution?

30lp/cm

true

3D printed anatomical parts can be used for surgery planning

false

3D printing is not suitable for made-to-order fixtures in operating rooms

During which days in the life of an intracranial hemorrhage (ICH) is it likely to contain a hyperdense center surrounded by concentric areas of hyperdense and hypodense tissue?

4 days to 10 days

What is the expected HU value of a measurment taken in a lateral ventricle?

4 to 8

Radiation protection principles include all of the following except: 1)justification. 2)optimization. 3)dose limitation. 4)clarification.

4)clarification.

The following developments in CT were introduced during the period between 1973 and 1983 except: A. image quality improvements. B. quality control (QC). C. detectors. D. Multislice CT (MSCT).

4. Multislice CT (MSCT)

What is the tube rotation of an overscan?

400 degrees

The normal white blood cell count for an adult ranges from

5,000 to 10,000/mm3 of blood.

What is the dose limit for radiation workers in the United States?

50 mSv/year

The term LD 50/30 signifies the whole-body dose of radiation that can be lethal to

50% of the exposed population in 30 days.

What window width should be used for tissue types with similar densities?

50-500HU

What percent of total energy is obtained from the oxidation of fatty acids?

50-70%

At what age does bowl activity decrease?

How many times more common are adrenal masses that are benign cortical adenomas than those that are primary adrenal cortical carcinomas.

60 mins

How many times more common are adrenal masses that are benign cortical adenomas than those that are primary adrenal cortical carcinomas.

60 time

Beta-blockers are used as part of a CT cardiac protocol to lower the heart rate to less than how many beats per minute (bpm)?

65 to 70 bpm

Beta-blockers are used as part of a CT cardiac protocol to lower the heart rate to less than how many beats per minute (bpm)?

65-70 bpm

A single-sided DVD can store about___times the amount of data as a CD.

An ROI is placed on the adrenal mass; unenhanced = 30 HU; enhanced = 120 HU; 15-minute delayed = 45 HU. What is the % washout?

83%

hearing aid

99% of what common medical aid is now custom-made by 3D printing?

A low-osmolality contrast media is how many times greater than the osmolality of blood? A) 2 times B) 4 times C) 7 times D) 10 times

A number of independent studies have established a link between effective communication and a reduction in malpractice claims. A) True B) False

End-users interact directly with client computers to send data requests to one or more connected servers. A) True B) False

For CT of the foot, when the patient is positioned with knees bent, feet flat on the scan table, and the gantry is angled perpendicular to the subtalar joint, data are acquired directly in which plane? a. oblique coronal b. transverse c. sagittal d. axial

For a patient's consent to be valid, she must be considered competent to make the decision at hand and her consent must be voluntary. A) True B) False

For what flow rate is a 20-gauge of larger catheter preferable? a. 3 mL/s of higher b. 4 mL/s or higher c. 5 mL/s or higher d. 6 mL/s or higher

Given the same dose of radiation, how many times more likely is it for a 1-year-old infant to develop a malignancy than it is for a 50-year-old adult? a. six times b. ten times c. twenty times d. one-hundred times

How are delayed reactions to intravascular iodinated contrast medial defined? A) Reactions occurring between 1 hour and 1 week after contrast medium injection. B) Reactions occurring between 1 hour and 1 day after contrast medium injection. C) Reactions occurring between 1 day and 1 month after contrast medium injection. D) Reactions occurring between 1 day and 1 week after contrast medium injection.

How can dose rates be minimized when CTF is used? a. by exclusively using intermittent fluoroscopy b. by increasing the tube current c. by changing the type of instrument used d. by changing the patient's position

How many centigray (cGy) are equivalent to 1 radiation absorbed dose (rad)? a. 1 b. 10 c. 100 d. 1000

How many grams of iodine will be delivered when 150 mL of an agent with a concentration of 300 mgI/mL is injected? A) 45 g B) 450 g C) 4500 g D) 45,000 g

In a patient who is lactating, what percent of the dose of contast agent given is excreted into breast milk? A) 0% to 1% B) 1% to 5% C) 5% to 10% D) 10% to 12%

In the medical context, the person committing battery does not have to intend harm. A) True B) False

In what units is bandwidth commonly expressed? A) Bits per second B) Bytes per second C) Megabytes per second D) Kilobytes per second

Lossy compression methods introduce compression artifacts because not all data are restored. A) True B) False

The result of an insufficient number of data samples for the spatial frequencies encountered in the body

Aliasing

Prior to an examination, scanner calibrations and tube warm-up procedures should be done while the room is free of both patients and CT staff. A) True B) False

The process for initiating inpatient examinations is the same as that for outpatients. A) True B) False

Warming a contrast agent reduces viscosity. A) True B) False

What are the computers that are integral to the functioning of the PACS called? A) Core servers B) Nodes C) Client servers

What barrier to communication is likely to occur when the receiver doesn't like portions of the sender's message? A) Receiver distortion B) Assumptions C) Fuzzy transmission D) Language

What is another name for the bolus phase of tissue enhancement? a. arterial phase b. venous phase c. nonangiographic phase d. aortic phase

What is the classification for urine output greater than 6,000 mL? A) Oliguric B) Polyuric C) Nonoliguric D) Anuric

What is the name of the universally adopted standard for medical image interchange? A) DICOM B) HL7 C) ACR D) NEMA

What is the preferred medical term used to describe an acute episode of interrupted blood flow to the brain that lasts longer than 24 hours? a. completed stroke b. thrombotic stroke c. lacunar stroke d. embolic stroke

What is the primary criteria in the selection of mAs? a. patient size b. the region to be scanned c. the clinical indication that prompted the scan d. cost

What plays the biggest role in body language? A) The face B) Gestures C) Posture

What, as a general rule, is the normal range for partial thrombo-plastin time (PTT)? A) 25 to 55 seconds B) 15 to 25 seconds C) 10 to 15 seconds D) 5 to 25 seconds

What, as a general rule, is the normal range for serum creatinine? A) 0.6 to 1.7 mg/dL B) 0.3 to 0.77 mg/dL C) 0.2 to 1.77 mg/dL D) 6 to 17 mg/dL

When is the radiosensitivity of a developing fetus is the greatest? a. from conception to 3 months b. from 3 months to 6 months c. from 6 months to 9 months

Which cavity of the heart sends blood only to the lungs? a. right ventricle b. left ventricle c. right atrium d. left atrium

Which factors that affect the degree of contrast enhancement in human tissue are largely controllable by the technologist? a. pharmacokinetic b. patient c. equipment

Which formula can be used to calculate SUV? a. SUV= ROI/ injection dose/patient weight

Which has the greatest storage capacity? A) Blu-ray disk B) CD C) DVD

Which is a drawback of using noncontrast helical CT (NCHCT) to diagnose urethral calculi? a. it is relatively expensive when compared to other methods b. ureteral stones are not seen c. radiolucent stones are now seen d. use of contrast media is necessary

Which is a generic term for a digital patient record? A) Electronic health record B) Digital health record C) Computerized health record D) Patient health record

Which is considered to be a low-density contrast agent? A) carbon dioxide B) water C) barium D) iodine

Which is not a goal of the questions included on the CT history? A) choosing the proper technologist B) correct selection of protocol C) patient safety D) providing information useful for interpreting the examination

Which is not a location where normal physiologic accumulation of FDG occurs? a. lungs b. brain c. salivary glands d. thyroid gland

Which of the following is not true when giving a contrast injection to a patient with an existing indwelling peripheral venous catheter? a. existing medications should be turned off for the duration of the CT exam b. the line should be flushed with saline solution before the contrast injection c. the line should once again be flushed with saline solution before medications are restarted d. patient medications should be restarted at the identical preexamination rate

Which pulse is taken behind the knee? A) Popliteal pulse B) Radial pulse C) Pedal pulse D) Femoral pulse

Which statement about CT arthrography of the shoulder is not true? a. it is not useful for evaluation of the joint capsule and intercapsular structures b. it is useful for finding loose bodies within the joint c. it can be performed either with a single or double contrast technique

Which statement about CT interventional procedures is not true? a. because of radiation dose concerns, patients are limited to single position during the procedure b. because the tip of the needle within the structure can be visualized and slice thickness can be narrow as 0.5 mm, interventions can be performed on small structures c. CT images permit the clinician to plan an access route to the lesion by showing the relationship of surrounding structures d. high resolution CT images provide precise three-dimensional localization of lesions

Which statement about multidetector row CT is not true? a. it allows the acquistion of slices as thin as 0.2 mm b. it allows extensive anatomic coverage c. it allows multiplanar reformation images to be created in any plane with the same spatial resolution as the original sections

Which type of CVC has the lowest incidence of injection? a. ports b. tunneled catheter c. non-tunneled catheter

Which is a TRUE statement regarding an emergency department patient who is suspected of suffering from acute stroke?

A CT scan of the head must be done as soon as possible because it is a necessary examination in determining whether a patient can receive t-PA treatment.

a tooth

A CT scan of the sinuses on the coronal plane is shown in the image. What does number 11 point to?

Which of the following statements is true?

A large object will have a low spatial frequency, and small objects will have a high spatial frequency.

What is interpolation?

A mathematical method of estimating an unknown value using the known values on either side of the unknown

The DAS reads each arriving ray and measures how much of the beam has been attentuated. This is _________.

A ray sum

Which type of artifact will appear on a digital image as a result of poor sampling of the analog signal?

Aliasing

What is cardiac gating?

A technique for cardiac CT acquisition that attempts to use only those images acquired during periods of lowest cardiac motion

The whole-body TEDE regulatory limit for exposed personnel is and for the general public. A. 0.05 Sv; 0.001 Sv B. 0.15 Sv; 0.015 Sv C. 0.25 Sv; 0.025 Sv D. 0.5 Sv; 0.1 Sv

A. 0.05 Sv; 0.001 Sv

Which of the following groups of cells is least radiosensitive? A. Adult nerve cells B. Nerve cells in an embryo-fetus C. Lymphocytes D. Immature spermatogonia

A. Adult nerve cells

Which of the following is not another term for coherent scattering? A. Characteristic B. Classical C. Elastic D. Unmodified

A. Characteristic

Which of the following statements below is true? A. It appears that no safe dose level exists for radiation-induced malignant disease. B. The ALARA principle establishes a dose level for radiation-induced malignancy. C. The BERT method establishes a dose level for radiation-induced malignancy. D. The NEXT program and reference values establish a dose level for radiation-induced malignancy.

A. It appears that no safe dose level exists for radiation-induced malignant disease.

Revised concepts of radiation exposure and risk have brought about more recent changes in NCRP recommendations for limits on exposure to ionizing radiation. Because many conflicting views exist on assessing the risk of cancer induction from low-level radiation exposure, the trend has been to A. create more rigorous radiation protection standards. B. reduce rigorous radiation protection standards. C. eliminate radiation protection standards. D. leave radiation protection standards the same as they have been for the last 20 years.

A. create more rigorous radiation protection standards.

The prodromal stage of acute radiation syndrome is actually the A. initial stage. B. latent period. C. manifest illness period. D. recovery period.

A. initial stage

What types of artifacts can arise from insufficient projection sampling or from insufficient view sampling?

Aliasing artifacts

What is the most common symptom of appendicitis?

Abdominal pain

In creating a surface rendered image, what can happen if the threshold set is too narrow?

Actual protruding structures can be imperceptible

Which of the following must always be the first step in protection of the reproductive organs?

Adequate and precise collimation of the radiographic beam to include only the anatomy of interest

Which of the following statements is true?

After chemotherapy, there is increased uptake as a result of bone marrow recovery that usually resolves 1 month after therapy.

Which of the following refers to a defined set of instructions for solving a problem?

Algorithm

A precise set of steps to be performed in a specific order to solve a problem describes:

An algorithm

A CT artifact is:

An anomaly in the CT image

What is typically the point of the cardiac cycle with the least cardiac motion?

At end-diastole

Which of the following humans is most radiosensitive?

An embryo-fetus during the first trimester of pregnancy

Which system compnent converts the projection attentuation data into the proper digital form for the array processor?

Analog to digital converter

What is the name the technique that is used to dilate an area of arterial blockage using a catheter with a small, inflatable, sausage-shaped balloon at its tip?

Angioplasty

Which heart valve is in the right side of the heart, between the left ventricle and the entrance to the aorta?

Aortic

Which causes a decrease in FDG uptake?

Areas that have been treated with radiotherapy

Which describes CABG?

Arteries or veins taken from elsewhere in the patient's body are grafted from the aorta to the coronary arteries to bypass atherosclerotic narrowings and improve the blood supply to the coronary circulation supplying the myocardium.

A distortion or error in an image that is unrelated to the subject being studied

Artifact

What term refers to the automatic control of the milliamperage in two directions during data acquisition by specific technical procedures?

Automatic tube current modulation (TCM)

About what percent of the general population has a ramus intermedius artery? a. 5% b. 10% c. 20% d. 50%

Adding an iodinated agent to the bloodstream will temporarily decrease the beam-attenuating ability of the blood. A) True B) False

After the intravenous administration of a bolus of contrast material, when does the hepatic arterial phase typically occur? a. 0-5 secs b. 15-25 sec c. 30-60 sec d. 60-70 sec

Approximately how long after the intravenous FDG injections is placed on the examination table? a. 15-30 min b. 30-60 min c. 60-90 min d. 90-120 min

Communication is the transmission of meaning. A) True B) False

For CT of the ankle, the display field of view (DFOV) does not need to include which of the following? a. the proximal bases of all five metatarsals b. the entire forefoot c. the midfoot d. the hindfoot

For which of the following is intravenous contrast medium not necessary or helpful? a. evaluating the vascularity of a tumor b. evaluating a scaphoid fracture c. showing the relationship of major arteries or veins to musculoskeletal masses

How does filtration affect the radiation dose? a. by increasing rotation to greater that 360 degrees b. by removing some of the soft x-rays c. be decreasing the pitch d. by increasing scan field diameter

How many grams of iodine will be delivered when 100 mL of an agent with a concentration of 375 mgI/mL is injected? A) 3.75 g B) 37.5 g C) 3750 g D) 37,500 g

How many hours is a patient required to fast before a PET examination? a. from 2-4 hours b. from 4-6 hours c. from 6-8 hours d. from 10-12 hours

How much do extra images add to the patient's radiation dose from the examination? a. approx. 1% b. approx. 10% c. approx. 25% d. approx. 50%

In communication, you should assume that a nonresponsive patient cannot hear you. A) True B) False

Networks that use radio waves to transmit data between computers are referred to as "wired". A) True B) False

Open ended questions invite a narrative response from a patient. How long is an uninterrupted narrative response on average? A) 15-30 seconds B) 30 seconds to 1 minute C) 1 minute to 2 minutes D) 3 minutes to 5 minutes

Research has found that African-Americans stand closest to one another. A) True B) False

The practice of acquiring a signed consent form is a practice that is universally accepted for routine CT examinations. A) True B) False

What barrier to communication is likely to occur when either the sender or receiver is insecure or suffer from low self-esteem? A) Fuzzy transmission B) Power struggles C) Receiver distortion D) Language

What do social psychologists estimate as the percent in loss of meaning in the transmission of messages from sender to receiver? A) 10% to 25% B) 40% to 60% C) 30% to 50% D) 0% to 10%

What is a computer network? A) Multiple input devices used on a single computer B) A group of two or more computers linked together C) Multiple output devices used on a single computer D) A group of two or more processors on a workstation

What is considered personal distance for North Americans? A) 18 inches or less B) 1.5 to 4 feet C) 3-6 feet D) 6-10 feet

What is creatinine? A) A tough white fibrous capsule that encases each kidney B) A by-product of muscle protein metabolism generated by the body at a fairly steady rate and excreted entirely in the urine C) A contrast reaction that stems from the contrast agent's pharmacologic properties D) Diminished urine formulation

What is frame grabbing? A) When an image on the monitor is converted to analog format B) When an image on the monitor is converted to digital format C) When an image on the monitor is compressed D) When an image on the monitor is transmitted

What is the approximate normal adult glomerular filtration rate (GFR)? A) 80 mL/min B) 120 mL/min C) 180 mL/min D) 220 mL/min

What is the goal of data compression? A) To route data from one computer to another B) To minimize the size (in bytes) of an image file without degrading the quality of the image to an unacceptable level C) To increase the bandwidth of a WAN

What is the most accurate method for transmitting orders to the radiology department? A) Via phone. The ordering physician gives the order verbally to the radiology department. B) Via an electronic system in which the ordering clinician places the electronic order herself. C) Via the patient. The ordering physician gives the order to the patient who in turn takes it to the radiology department.

What is the primary complication of CT-guided lung biopsies? a. spreading of cancer cells b. pneumothorax c. infection d. bleeding

What is the quality factor for the diagnostic x-rays that are used in CT? a. 0 b. 1 c. 5 d. 10

What is the range of the average adult pulse? A) 40 to 80 bpm B) 60 to 100 bpm C) 70 to 110 bpm D) 80 to 120 bpm

What is the typical single dose of iodinated contrast agents? A) Between 50 and 100 mL B) Between 100 and 150 mL C) Between 150 and 175 mL D) Between 175 and 200 mL

What type of stroke occurs as a result of blood pressure that is too low? a. hemorrhagic b. hypotensive c. ischemic

What, as a general rule, is the normal range for platelet count? A) 100,000 to 300,000 cubic millimeters B) 150,000 to 400,000 cubic millimeters C) 175,000 to 375,000 cubic millimeters D) 200,000 to 500,000 cubic millimeters

When is the bladder best appreciated on CT? a. when empty b. when 100% filled with urine c. when 50% filled with urine d. when 25% filled with urine

When storing large amounts of data, tape can be substantially more expensive than other data storage options. A) True B) False

Which causes a decrease in FDG uptake? a. areas that have been treated with radiotherapy b. autoimmune disease c. Crohn's disease d. granulomatous disease

Which causes multiple scan average doses (MSAD) to increase? a. gaps between the slices b. overlapping slices c. using single slices

Which is a communication habit to avoid? A) Asking questions of a listener to see whether he or she understands B) Using false reassurance C) Nodding or head-shaking D) Acknowledging the many possibilities for misunderstanding

Which is a disadvantage to using MDCT in the diagnosis of pulmonary emboli? a. it is not cost-effective b. the visualization of smaller arteries can be affected by problems with technique of suboptimal vessel opacification c. scans are obtained at a slow rate

Which is a typical soft-tissue window setting? a. window width 650; window level 60 b. window width 450; window level 50 c. window width 1000; window level 500 d. window width 2000; window level 60

Which is an example of a moderately adverse idiosyncratic patient reaction? A) Cough B) Hypertension C) Convulsions D) Itching

Which is another name for prospective ECG gating? a. retrospective ECG gating b. cine-mode scanning c. ECG triggering d. ECG tracing

Which is not a common anticoagulant medication? A) Heparin B) Wellbutrin C) Aspirin D) Plavix

Which is not a network routing mechanism? A) Hubs B) LANs C) Switching D) Bridging

Which is not a possible shape of the adrenal glands on a cross-sectional image? a. Y shape b. C shape c. T shape d. V shape

Which is not a primary factor of special relevance to the use of CT in pediatric radiology? a. increased sensitivity b. increased examination cost c. higher effective dose d. increasing use

Which is not a task of the radiology information system? A) Scheduling patients B) Image archiving C) Protocoling examinations D) Patient tracking

Which is not true about the effects of iodinated contrast agents on thyroid function? A) In the absence of thyroid disease the administration of iodinated contrast agents will have no significant impact on thyroid function. B) In patients with hyperthyroidism, iodinated contrast media can often precipitate thyroid storm C) In patients with hypothyroidism, particularly those with autoimmune thyroiditis, there may be a small, temporary reduction in thyroid function, which does not require additional treatment. D) In patients with a history ot hyperthyroidism, iodinated contrast media can intensify thyroid toxicosis

Which should not be used for verifying a patient's identity? A) Checking the patient's armband B) The name posted above the patient's bed C) Verifying identity with family members D) Asking the patient to tell you his birth date

Which statement about musculoskeletal scanning methods is not true? a. it has the ability to perform multiplanar and three-dimensional reformation retrospectively b. it has relatively poor contrast sensitivity c. it has the ability to image both sides of the body to permit comparison d. it displays cross-sectional anatomy and spatial relationships

Which statement is not true about a LAN? A) It typically uses Ethernet cables to connect computers B) The computers in a LAN are geographically distant C) It can be a combination of network topologies D) A LAN can be a wired network

Why would a patient history form ask if the patient has a history of hyperthyroidism? A) To determine the amount of radiation that can be safely administered B) To assess whether the patient can safely receive an iodinated contrast agent C) To assess the patient's tolerance for closed spaces D) To determine whether the patient could be allergic to the contrast agent

With intravenous administration, what is the risk of recurrent reaction in a patient with a prior reaction when HOCM is used? A) 5% to 10% B) 16% to 35% C) 10% to 50% D) 100%

To provide a low-exposure cut-off level so that regulatory agencies may consider a level of effective dose as being of negligible risk, an annual negligible individual dose (NID) of per source or practice has been set. A. 0.001 mSv/year B. 0.01 mSv/year !! C. 0.1 mSv/year D. 1.0 mSv/year

B. 0.01 mSv/year

A biologic reaction is produced by 4 Gyt of a test radiation. It takes 16 Gyt of 250-kVp x-rays to produce the same biologic reaction. What is the relative biologic effectiveness (RBE) of the test radiation? A. 2 B. 4 C. 8 D. 12

B. 4

Which of the following is a method of explaining radiation to the public? A. ALARA B. BERT C. ORP D. NEXT

B. BERT

Which of the following is not a type of interaction between x-radiation and biologic matter? A. Compton scattering B. Bremsstrahlung C. Pair production D. Photoelectric absorption

B. Bremsstrahlung

Which of the following is not a source of image noise? A. X-ray flux B. CT scanner model C. Physical limitations of the system D. reconstruction parameters

B. CT scanner model

Which form of imaging primarily uses DSCT scanners? A. Virtual colonoscopy B. Cardiac imaging C. Biopsy procedures D. Pulmonary imaging

B. Cardiac imaging

Which of the following are classified as early tissue reactions of ionizing radiation? A. Erythema, cataract formation, and cancer B. Nausea, epilation, and intestinal disorders C. Male and female sterility, embryologic defects, and cancer D. Blood disorders, fever, and genetic effects

B. Nausea, epilation, and intestinal disorders

Each of the following are types of dosimeters that have previously been used to measure dose in CT except: A. film dosimeter B. electrometer C. TLD D. ionization chamber

B. electrometer

The radiosensitivity of ova A. remains constant throughout the lifetime of the germ cell. B. varies considerably throughout the lifetime of the germ cell. C. varies slightly throughout the lifetime of the germ cell. D. is insignificant because the germ cell is not radiosensitive.

B. varies considerably throughout the lifetime of the germ cell.

The process of converting the data from the attentuation profile to a matrix is known as:

Back projection

Partial volume artifacts appear as ______and _______

Bands and streaks

Which of the following is another term for use factor (U)?

Beam direction factor

Describes and increase in the mean energy of a polychromatic beam as it passes through an object

Beam hardening

Refers to an increase in the mean energy of the x-ray beam as it passes through the patient

Beam hardening

Which statement about CT interventional procedures is not true?

Because of radiation dose concerns, patients are limited to a single position during the procedure.

Why doesn't the uncoupling effect play a role when the mA or kVp setting is too low?

Because quantum noise will result and provide evidence of the inadequate exposure settings.

Which statement about adrenal lesions is true?

Benign adrenal lesions tend to grow slowly.

When does the peak effect of IV-push metoprolol occur?

Between 5 and 10 minutes after administration

What is the primary complication of all types of biopsy procedures?

Bleeding

For which condition of the spine is CT considered superior to MRI?

Bony abnormalities of the spine

How can dose rates be minimized when CTF is used?

By exclusively using intermittent fluoroscopy

A high-osmolality contrast media can be up to how many times greater than the osmolality of blood? A) Two times B) Four times C) Seven times D) Ten times

An ROI is placed on the adrenal mass; unenhanced =30 HU; enhanced =120 HU; 15-minute delayed = 45 HU. What is the % washout? a. 12% b. 63% c. 83% d. 93%

By how many Hounsfield units must two tissues differ to be visibly different on a CT scan? A) 1 HU B) 5 HU C) 10 HU D) 50 HU

For most patients, it is possible to scan both ankles simultaneously within what DFOV? a. 10 cm b. 16 cm c. 22 cm d. 28 cm

How many bits are in a byte of storage? A) 1 B) 2 C) 8 D) 128

How many methods of verifying a patient's identity are required? A) none B) at least one C) at least two D) at least three

How many radiation absorbed dose (rad) are equivalent to 1 gray (Gy)? a. 10 b. 50 c. 100 d. 1000

How much of a time delay is recommended when CT is performed after intrathecal contrast administration for fluoroscopic myelography? a. 15 to 30 minutes b. 30 minutes to 1 hour c. 1 to 3 hours d. 3 to 5 hours

If used, when is short-scting nitroglycerin given to the patient? a. two hours before scan initiation b. one hour before scan initiation c. immediately before scan initiation d. immediately after scan initiation

It is estimated that what percent of all pediatric CT examinations are not clearly indicated? a. 5% b. 10% c. 40% d. 60%

Proper street behavior among Americans permits passersby to look at each other until they are approximately how many feet apart? A) 2 feet B) 6 feet C) 8 feet D) 10 feet

Split-bolus injections divide the contrast media dose into two bolus injections with a delay of how much time between injections? a. 15-30 seconds b. 30 sec - 1 min c. 2 -15 minutes d. 15 - 30 minutes

Studies have shown that what percent of the meaning we derive from communication comes from the nonverbal cues that the other person gives? A) 50% B) 75% C) 90% D) 100%

The SUV of the liver should be in what range? a. 1 to 1.5 b. 1.5 to 2 c. 2 to 2.5 d. 2.5 to 3

What is considered intimate distance for North Americans? A) 12 inches or less B) 15 inches or less C) 18 inches or less D) 25 inches or less

What is the approximate half-life of the iodinated contrast media? A) 30 minutes B) 1 hour C) 2 hours D) 4 hours

What is the first step in the CT process as defined by the text? A) Obtain the patient's medical history B) Verify the order C) Prepare the room D) verify patient identity

What is the most common formula for calculating the dose of intravascular contrast for pediatric CT studies? A) 0.5 mL/kg B) 1 mL/kg C) 2 mL/kg D) 4 mL/kg

What is the trade-off for the excellent low-contrast resolution that is seen on CT images? a. less patient comfort during examinations b. decreased detector efficiency c. a relatively high radiation dose d. the need for highly-trained technologists

What percent of total energy is obtained from the oxidation of fatty acids? a. 10%-20% b. 20%-50% c. 50%-70% d. 70%-80%

What type of contrast agent has osmolality equal to that of blood? A) High-osmolality contrast media B) Low-osmolality contrast media C) Isomolar contrast agent

When does contrast enhancement typically reach a near-peak in the aorta? a. from 5 to 12 seconds after the start of the injection b. from 10 to 15 seconds after the start of the injection c. from 15 to 22 seconds after the start of the injection d. from 25 to 30 seconds after the start of the injection

Which group is most prone to kidney stones? a. children b. young adults c. middle-aged people d. senior citizens

Which imaging structure creates images of the body's physiologic functions, such as blood flow and metabolism? a. CT b. radiography c. PET d. MRI

Which is a drawback to using sequential CT scanning for intervention procedures? a. interventions cannot be performed on small structures b. low-density material is not imaged well c. the procedure can be lengthy

Which is bandwidth? A) A strategy for routing data between computers in a network B) The width of the Ethernet cable connecting computers in a network C) The amount of data that can be transmitted between two points in the network in a set period of time D) A network topology

Which is the most common patient position for CT examinations of the wrist? a. having the patient rest his wrist on his abdomen b. having the patient sit or stand at the far end of the CT scanner with his arm resting on the CT table c. extending the patient's arm over the head

Which is true about meanings with respect to communication? A) Meanings are not entirely contained in the message. They are interpreted by the message senders. B) Meanings are never contained in the message. C) Meanings are not entirely contained in the message. They are interpreted by the message receivers. D) Meanings are entirely contained in the message.

Which nonverbal communication category includes facial expression and posture? A) Distance B) Tactile C) Visual D) Vocal

Which nonverbal communication category involves the use of touch to impart meaning? A) Visual B) Distance C) Tactile D) Vocal

Which nonverbal communication category refers to the intonation of a person's voice? A) Visual B) Tactile C) Vocal D) Distance

Which of the following statements is true? a. in general lower accumulations of FDG usually correlate with more aggressive tumors and a greater number of viable tumor cells b. in general higher accumulations of FDG usually correlate with more aggressive tumors and a lesser number of viable tumor cells c. in general higher accumulations of FDG usually correlate with more aggressive tumors and a greater number of viable tumor cells

Which patient factor effecting contrast enhancement has a pronounced effect on the degree of aortic and parenchymal enhancement? a. renal function b. gender c. weight d. cardiac output status

Which pulse is taken in the groin? A) Pedal pulse B) Radial pulse C) Femoral pulse D) Popliteal pulse

Which is a not a possible shape of the adrenal glands on a cross-sectional image?

C shape

Lysosomes are sometimes referred to as "suicide bags," because the enzymes they contain can break down and digest not only proteins and certain carbohydrates but also the cell itself should the lysosome's surrounding membrane rupture. Exposure to radiation may induce such a rupture. When this occurs what will happen to the cell? A. It will multiply spontaneously. B. It will divide very rapidly. C. It is likely to die. D. There will not be any effect on the cell.

C. It is likely to die.

____________ are those items which identify process outcomes. A. Models B. IMprovements C. Specifications

C. Specifications

What do agents such as specific chemicals, viruses, and ionizing radiation have in common? A. Nothing B. They can increase the frequency of mutations in only those members of the population who are already genetically impaired. C. They are all mutagens that may increase the frequency of mutations. D. They always cause spontaneous abortions during the first trimester of pregnancy.

C. They are all mutagens that may increase the frequency of mutations

Existing data on radiation-induced genetic effects in humans A. prove conclusively that radiation causes major genetic effects. B. prove conclusively that radiation causes only minor genetic effects. C. are both contradictory and inconclusive. D. prove conclusively that radiation does not cause genetic effects.

C. are both contradictory and inconclusive.

Direct action may occur after exposure to any type of radiation, but it is much more likely to happen after exposure to A. low-LET radiation such as x-rays. B. low-LET radiation such as gamma rays. C. high-LET radiation such as alpha particles. D. nonionizing radiation such as microwaves.

C. high-LET radiation such as alpha particles.

he steps, or rungs, of the DNA ladder-like structure consist of complementary chemicals that are A. acetic acids. B. fatty acids. C. pairs of nitrogenous bases. D. sugar-phosphate compounds.

C. pairs of nitrogenous bases.

Which electronic system allows clinicians to imput an electronic order for a CT examination and transmits that order to the CT department?

CPOE

Any discrepancy between the reconstructed CT numbers in the image and the true attenuation coefficients of the object

CT Image Artifact

helical

CT angiography (CTA) of the head and neck are usually done using which scan method?

helical

CT angiography (CTA) studies of the head and neck are usually done using which scan method?

What are the most common interventional procedures?

CT guided biopsies

The most obvious difference between CT and radiography is that:

CT shows cross-sectional images or transaxial anatomy.

Which is not a factor that affects contrast resolution?

CTDI phantoms

is a relatively new imaging examination designed to provide a comprehensive evaluation of the upper and lower urinary tract

CTU

Which of the following late effects caused by exposure to ionizing radiation is considered to be most important?

Cancer

Which of the following curves illustrates the radiation sensitivity of a particular type of cell?

Cell survival curve

Abdominal ultrasonography to evaluate right lower quadrant or pelvic pain is particularly suited to which group?

Children

Which is another name for prospective ECG gating?

Cine-mode scanning

The vascular structure located on the floor of the cranial cavity is called the ______________.

Circle of Willis

Who was the first American radiation worker to die from radiation-induced cancer in October of 1904?

Clarence Madison Dally

The enormous heat that builds up in the CT tube is caused by the:

Collision of the electron beam with the tungsten target on the tube anode

A cone beam artifact may look like stars:

Coming from the structures around he edge of the image

What is the preferred medical term used to describe an acute episode of interrupted blood flow to the brain that lasts longer than 24 hours?

Completed stroke

________________ made helical imaging possible.

Continuous rotation scanners

Where the CT number difference between objects and background is small

Contrast resolution

Which of the following allows the technologist to devote more time to the scanning procedure and the needs of the patient?

Control functions

A patient who is scheduled for a CT study has an irregular heartbeat with a rate of approximately 85 bpm. For which clinical indication is this the most problematic?

Coronary artery disease

What unit is used to measure radiation exposure in the metric International System of Units?

Coulomb per kilogram

This dictates that for a uniform phantom, the CT number measurement should not change with the location of the selected ROI or with the phantom position relative to the isocenter of the scanner

Ct number uniformity

Among healthcare workers, what has been cited as the primary reason for not talking more with patients? A) Poor patient communication skills B) Poor worker communication skills C) Language barriers D) Lack of time

Beta blockers are used as part of a CT cardiac protocol to lower the heart rate to less than how many beats per minute? a. 50 to 55 bpm b. 55 to 60 bpm c. 60 to 65 bpm d. 65 to 70 bpm

For which protocol is the split-bolus technique for contrast administration typically used? a. spine b. brain c. abdomen d. neck

For which suspected condition are images of the liver typically acquired in a single (portal venous) phase? a. renal cell carcinoma b. primary tumors of the thyroid c. melanoma d. primary tumors of the lung

How many times more common are adrenal masses that are benign cortical adenomas than those that are primary adrenal cortical carcinomas? a. 5 times b. 10 times c. 30 times d. 60 times

In conventional film-screen radiography, how much of the radiation does the skin of the entrance plane receive? a. 10% b. 50% c. 80% d. 100%

What barrier to communication is a result of messages being unreliable or inconsistent? A) Power struggles B) Language C) Receiver distortion D) Fuzzy transmission

What does a CT calcium score of 1-10 indicate? a. mild plaque b. no plaque c. extensive plaque d. minimal plaque

What is considered public distance for North Americans? A) 4 feet or more B) 6 feet or more C) 8 feet or more D) 12 feet or more

What is considered social distance for North Americans? A) 18 inches or less B) 12 feet or more C) 1.5 to 4 feet D) 4-12 feet

What is the lifetime rate of appendectomy for women if incidental appendectomies are included? a. 7% b. 12% c. 18% d. 25%

What is the primary complication of all types of biopsy procedures? a. spreading of cancer cells b. inflammation c. infection d. bleeding

What is the ratio of respiration to pulse? A) Approximately 4 breaths to 4 heart beats B) Approximately 2 breaths to 4 heart beats C) Approximately 1 breath to 3 heart beats D) Approximately 1 breath to 4 heart beats

What, as a general rule, is the normal range for blood urea nitrogen (BUN)? A) Between 0 and 2.5 mg/dL B) Between 2 and 15 mg/dL C) Between 7 and 45 mg/dL D) Between 7 and 25 mg/dL

What, as a general rule, is the normal range for prothrombin time (PT)? A) 2 to 5 seconds B) 6 to 10 seconds C) 8 to 12 seconds D) 11 to 14 seconds

When muscle uptake is focal and unilateral interpretation is especially more difficult in patients who have which of the following? a. lung or esophageal cancer b. thyroid cancer c. stomach cancer d. head and neck cancer or lymphoma

When sinus screening is done for chronic sinusitis, which of the following is true? a. the study is done with IV contrast enhancement and scanning is done in the axial plane b. the study is done without IV contrast enhancement and scanning is done in the axial plane c. the study is done with IV contrast enhancement and scanning is done in the coronal plane d. the study is done without IV contrast enhancement and scanning is done in the coronal plane

Which describes how pitch has a direct influence on patient radiation dose? a. as pitch decreases, the time that any one point in space spends in the x-ray beam is increased b. as pitch decreases, the time that any one point in space spends in the x-ray beam is decreased c. as pitch increases, the time that any one point in space spends in the x-ray beam is increased d. as pitch increases, the time that any one point in space spends in the x-ray beam is decreased

Which heart valve has three folds and is in the right side of the heart, between the right atrium and the right ventricle? a. aortic b. pulmonary c. mitral d. triscuspid

Which helps to reduce artifacts created by respiratory motion? a. having the patient in the prone position b. acquiring the scan using multiple breath holds c. having the patient in a supine position d. using the shortest scan time possible

Which is a typical bone window setting? a. window width 650; window level 60 b. window width 450; window level 50 c. window width 1000; window level 500 d. window width 2000; window level 600

Which is not a reason for increased uptake in the breast? a. dense breasts b. hormonal therapy c. menstruation d. lactation

Which is not a strategy for reducing CT radiation dose? a. consider alternative modalities b. limit the region covered c. consider patient shielding d. maximize the use of thin slices

Which is not an optical storage device? A) CD B) DVD C) Blu-ray disk D) RAID

Which is not information that the technologist should provide to educate the patient? A) Whether contrast agents will be administered B) The approximate length of time of the procedure C) How the procedure is carried out D) False reassurance to help alleviate patient fears

Which website resource provides essential radiation safety for the pediatric community?

Image Gently®

Which pulse is taken at the thumb side of the wrist? A) Popliteal pulse B) Pedal pulse C) Femoral pulse D) Radial pulse

Which stroke risk factor contributes to 70% of all strokes? a. obesity b. heredity c. atrial fibrillation d. hypertension

Who typically determines the proper protocol for a CT examination? A) The ordering physician B) A technologist C) The attending nurse D) A radiologist

Why is the tunneled catheter the best choice when access to the vein is needed for long periods of time and when the line will be used many times each day? a. it is less expensive b. it is easier to insert than a non-tunneled catheter c. it is lighter in weight than a PICC line d. it is secure and easy to access

Which of the following is not a start-up step in the CDM model? A. Identify customer's expectations and professional standards B. Balance customer's needs with operational requirements C. Decide on outcomes and processes measurements D. Report results and provide feedback

D. Report results and provide feedback

Radiation-induced cataracts in humans follow a ______ dose-response relationship. A. nonthreshold, nonlinear B. nonthreshold, linear C. threshold, linear D. threshold, nonlinear

D. threshold, nonlinear

What dose descriptor is used to describe a measurement of the total amount of exposure for a series of scans?

DLP

Radiation-induced abnormalities are caused by unrepaired damage to

DNA molecules in the sperm or ova of an adult.

Decreasing the number is projections will ______ the amount of data thereby decreasing spatial resolution

Decrease

Increasing the beam filtration and patient size _____ photon flux

Decreases

How does a decease in section thickness affect spatial resolution?

Decreasing section thickness increases spatial resolution

Which of the following could allow for a reduction of partial volume artifact while not increasing the appearance of the noise in the image?

Decreasing slice thickness while increasing mAs

Which is the first step in many image display and measurement functions?

Defining a region of interest

Compared with a cerebral CTA, what parameter must be changed for a cerebral CTV?

Delay from the start of injection to the start of scanning is increased.

Which of the following serves as a prototype for messenger RNA (mRNA)?

Deoxyribonucleic acid (DNA)

Which of the following provides the basis for determining whether an imaging procedure or practice is justified?

Diagnostic efficacy

One industry standard in data transfer and connectivity is:

Digital Imaging and Communications in Medicine (DICOM).

CT is commonly referred to as all of the following names EXCEPT:

Digital Subtraction Angiography

Which registry collects CT exam doses and transmits them to the American College of Radiology (ACR) to provide feedback and compare institutions?

Dose Index Registry (DIR)

Which of the following radiation quantities is intended to be the best overall measure of the biologic effects of ionizing radiation?

Effective dose

Occurs because of random electrical interference within the myriad electronic component in the system

Electronic noise

During the preimplantation stage of development, the fertilized ovum divides and forms a ball-like structure containing undifferentiated cells. If this structure is irradiated with a dose in the range of 0.05 to 0.15 Gyt which of the following will result?

Embryonic death

Which of the following cause an increase in cellular activity that in turn causes biochemical reactions to occur more rapidly to meet the needs of the cell in stressful situations?

Enzymes

T of F Scans of the lower extremities are usually scanned with the patient supine and placed head first into the scanner

T or F CT and MRI has a high sensitivity for the detection of obvious structural disruption and is useful in characterizing these abnormalities as malignant or benign.

T or F CTF allows for the near real-time capabilities or traditional fluoroscopy but does not provide the superior contrast resolution of CT

T or F If the vein selected for placement does not adequately distend with the tourniquet, place a second tourniquet just below the first and hang the arm below the level of the heart

T or F Sinus screening is always done with IV contrast media

All images displayed for viewing by humans are in the spatial frequency domain.

False

Although factors affecting resolution are largely determined by CT manufacturers, operators do have a great deal of control.

False

Ambrose received the Nobel Prize in 1979 with Hounsfield.

False

CT and CT fluoroscopy (CTF) must be used separately and cannot be used in combination. (True or False)

False

CT fluoroscopy (CTF) allows for the near real-time capabilities of traditional fluoroscopy but does not provide the superior contrast resolution of CT (True or False)

False

Factors directly affecting CT dose cannot be controlled by the technologist.

False

Hardware refers to the instructions or programs written for the computer to solve problems in a specific way.

False

This type of mottle refers to either an unevenness in size or distribution of the silver halide crystals in the film emulsion

Film grain emulsion

List the three major types of mottle

Film grain mottle, screen mottle, and quantum mottle

What is the term for the number of x-rays emitted per inner-shell vacancy during the process of photoelectric absorption?

Fluorescent yield

During which of the following x-ray examinations should a radiographer always wear a thyroid shield?

Fluoroscopy and x-ray special procedures

Which of the following refers to a function that relates to the amplitude and phases of a sine wave and corresponds to a specific frequency?

Fourier Transform

All of the following were improvements necessary to make helical scanning possible EXCEPT:

Fourth generation scanner design

How many hours is a patient required to fast before a PET examination?

From 4-6 hours

Which is not a high-density material?

Gas

Which can most improve the demarcation of the esophagus and the gastroesophageal junction?

Giving the patient an oral contrast agent

Which are secreted by the middle region of the adrenal cortex?

Glucocorticoids

Which are secreted by the innermost region of the adrenal cortex?

Gonadocorticoids

Which of the following is a scavenger type of white blood cell that fights bacteria?

Granulocytes

If the range of Hounsfield numbers on the image is 50 to 50, a value of 0 will display as what color?

Gray

What is/are the unit(s) of absorbed dose?

Gray (Gy)

Which of the following belongs to the class of nonlinear image manipulation techniques?

Gray-scale manipulation

what kind of scanning is used for patients with diffuse lung disease?

HRCT

Which of the following is/are considered to be acellular tissue?

Hair and nails

What contribution did Cormack make to the development of clinical CT? A. He developed Britain's first business computer B. He developed programs to calculate doses to patients C. He developed the solutions to the mathematical problems in CT D. He performed a practical reconstruction of an image of the sun

He developed the solutions to the mathematical problems in CT

When muscle uptake is focal and unilateral interpretation is especially more difficult in patients who have which of the following?

Head and neck cancer or lymphoma

CT angiography (CTA) studies of the head and neck are usually done using which scan method?

Helical

An area where there is a sudden and quick drop in CT numbers

High contrast region

Selecting a ___ _____ ____ which is a bone algorithm or edge enhancing algorithm can aid in imaging high contrast regions

High pass filter

Which of the following describes the scanner's ability to resolve closely placed objects that are significantly different in the background? A. low-contrast resolution B. High-contrast resolution C. Accuracy D. Noise

High-contrast resolution

For what study might data be acquired while the patient is lying prone on the CT table?

High-resolution chest CT

During a radiographic examination, which of the following combinations of technical exposure factors reduce patient radiation dose?

Higher kVp, lower mAs

During a radiographic examination, which of the following combinations of technical exposure factors reduce patient radiation dose? A. Lower kVp, higher mAs B. Higher kVp, lower mAs C. Higher kVp, higher mAs D. Lower kVp, lower mAs

Higher kVp, lower mAs

In which of the following are pixels in a certain region of the image made to appear brighter?

Highlighting

VR techniques assign each voxel an opacity value based on its _________. This value determines the degree the voxel will contribute to the final image.

Hounsfield Units

Which stroke risk factor contributes to 70% of all strokes?

Hypertension

Which may induce uptake in the diaphragm?

Hyperventilation

What type of stroke occurs as a result of blood pressure that is too low?

Hypotensive

Describe the relationship between radiation dose and noise

If radiation dose increases , noise decreases

Which of the following statements is true?

In general, higher accumulations of FDG usually correlate with more aggressive tumors and a greater number of viable tumor cells.

How is dose area product usually specified?

In units of mGy-cm2

How will the application of a low-pass algorithm affect contrast resolution?

Increase contrast resolution

What is the most straightforward way to reduce or eliminate the motion of an object?

Increase scan speed

How would increasing matrix size affect spatial resolution

Increase spatial resolution (increase matrix size decreases pixel size)

What is Dunphy's sign of acute appendicitis?

Increased pain in the right lower quadrant with coughing

Increasing kVP and mAs ____ photon flux

Increases

Which classification of factors has a direct influence on image quality but no direct effect on radiation dose in CT?

Indirect

Which image processing hardware is responsible for high-speed processing of the input digital data?

Internal image processor

Which is not true about the effect of mAs and kVp setting on the radiation dose?

It is a more common to manipulate the kVp, rather than the mAs

A water phantom is scanned and several ROi's are placed in the resulting image. The standard deviation measurements from the ROI's range from 15-25. What can be said about the image?

It is noisy

Which is a drawback of using noncontrast helical CT (NCHCT) to diagnose ureteral calculi?

It is relatively expensive when compared to other methods.

What must happen to a thrombus for it to be referred to as an embolus?

It must detach from its original site.

Which statement is not true about the reference artery chosen during the post processing of CT perfusion scans?

It should be one of the last arteries to enhance.

The power capacity of the generator s listed in

Kilowatts (kW)

Which type of stroke occurs when a small artery, such as those that supply the deep cerebral white matter, is blocked?

Lacunar Stroke

Which correctly describes how the SUV correlates with the malignant potential of a lesion?

Lesions with values greater than 2.5 have been shown to have a high likelihood of malignancy, whereas lesions with values less than 2 are usually benign.

The in-plane resolution is specified in what terms

Line pairs per centimeter or line pairs per millimeter

What dose-response model is a radiation risk model most favored by radiobiologists in estimating the risk of exposure in radiology?

Linear nonthreshold (LNT)

Refers to the linear relationship between CT numbers to the linear attenuation coefficients of the object to be imaged

Linearity

Which of the following refers to the relationship of CT numbers to the linear attenuation coefficients of the object to be imaged?

Linearity

Which is part of the scanning step in cardiac CT imaging?

Load the dual-injector heads with saline and iodinated contrast material.

What should the patient be asked to do during a CT scan of the neck to reduce artifacts that degrade images in the lower neck?

Lower the shoulders as much as possible

Which is not a location where normal physiologic accumulation of FDG occurs?

Lungs

Which of the following groups of cells is most radiosensitive?

Lymphocytes

internal derangement of the knee

MRI is the primary modality for which type of knee trauma?

Equipment for 3D image processing does not include:

MRI scanner console

Who should determine the exact shielding requirements for a particular imaging facility?

Medical physicist

What is used to quantify the risk from partial body exposure to that from an equivalent whole-body dose?

Quantity effective dose

Which is not a reason for increased uptake in the breast?

Menstration

The artifact above is most likely caused by:

Metalic object

Which is the most commonly used beta-blocker for cardiac CT studies?

Metoprolol tartrate

Which group is most prone to kidney stones?

Middle aged

What does a CT calcium score of 1-10 indicate?

Minimal plaque

What quantifying method is the most commonly used for expressing spatial resolution

Modulation transfer function

What device is used to display CT images?

Monitor

are caused from thrombi originating in the lower extremities known as deep vein thrombosis (DVT).

Most pulmonary emboli

Which of the following generates sagittal, coronal, and paraxial images from transaxial slices?

Multiplanar reconstruction

A result of the limited number of photons contributing to the image

Quantum noise

For which protocol is the split-bolus technique for contrast administration typically used?

Neck

Which is not a factor that produces a high standard deviation?

No variation within the region of interest

The fluctuation of CT numbers from point to point in the image for a scan of uniform material such as water

Noise

The product of various types of mottle

Noise

This is characterized by graininess, or salt and pepper appearance that degrades an image, particularly low contrast resolution

Noise

Which of the following is NOT a true statement regarding PACS?

Once the hardware for the PACS is installed, the system runs virtually maintenance free

Which imaging structure creates images of the body's physiologic functions, such as blood flow and metabolism?

PET

Which of the following is TRUE as the slice thickness is decreased?

Partial volume artifacts and edge gradient artifacts decrease

Term used to describe a voxel value that is the average of multiple tissue types contained within the voxel?

Partial volume averaging

Which of the following is frequently a problem in diagnostic pediatric radiography?

Patient motion

Which of the following statements is true concerning patients who receive radiation exposure from a routine radiographic procedure such as a chest x-ray?

Patients are not expected to sustain appreciable damage to either the blood or the blood-forming organs as a consequence of the examination.

What portion of the collimated beam contributes to the patient's radiation dose but does not contribute to the produced image?

Penumbra

There is less beam hardening at the _______ of the object where the radiation path is short

Periphery

What is the term used to describe a ratio of the difference the table travels per revolution to nominal beam collimation?

Pitch

Which equation correctly describes the relationship between pixel size, matrix size, and DFOV?

Pixel size = DFOV/matrix size

What is the primary complication of CT-guided lung biopsies?

Pneumothorax

After the Chernobyl disaster in 1986, an attempt was made to prevent thyroid cancer in Poland and some other countries, resulting from the accidental overdose of iodine-131. _______________ was administered to children as a substitute to block the gland's uptake of iodine-131.

Potassium iodide

Which of the following is not a step in the processing of an object-based model into a simulated 3D image?

Preprocessing

Which stage of volume rendering assigns the different brightness levels or color to a voxel?

Preprocessing

For which suspected condition are images of the liver typically acquired in a single (portal venous) phase?

Primary tumors of the lung

What is dual window setting?

Recording two different window settings, superimposed on one another in a single image

What are the primary functions of a bow tie filter

Reduce beam hardening artifacts Reduce scatter radiation

Which is a disadvantage of a small focal spot size?

Reduced heat capacity

Which cavity of the heart sends blood only to the lungs?

Right Ventricle

Which cavity of the heart sends blood only to the lungs?

Right ventricle

_____ artifacts are a result of miscalibration of one detector in a rotate-rotate scanner

Ring

_____ artifacts are seen in third generation scanners when one detector's gain varies by 0.1% or more from that of adjacent detectors

Ring artifacts

If a detector is miscalibrated (off line by 0.01%) it will incorrectly record data in every projection resulting in a _____ around the image

Ring formation

Classification of artifacts on basis of appearance : Cause : Bad detector channels in third-generation CT scanners

Rings

Why is it recommended that cardiac CT calcium scoring be restricted to patients with risk factors for coronary artery disease, rather than using it as a screening tool for all patients?

Risks related to the radiation dose are a concern; for asymptomatic patients with no cardiac risk factors, it is not certain that the benefit of the examination outweighs the risk from the radiation exposure.

Which formula can be used to calculate SUV?

SUV = Radioactivity Concentration in ROI / (Injection Dose (bq) / Patient Weight (g))

In which of the following is the brightness level of each pixel in a picture measured by a photomultiplier tube (PM)?

Sampling

States that to faithfully represent a continuous signal , the sampling frequency (fN) must be at least twice the highest frequency content in the signal ( fH)

Sampling theorem

Determines the percentage of the x-ray photons exiting the patient that are converted to useful signals

Scanner efficiency

The ____ dictates the number of x-ray photons that reach the patient

Scanning technique

Which of the following represents the logical order in digitizing an image?

Scanning, sampling, and quantization

The unevenness in size or distribution of the fluorescent crystals in the screen .

Screen mottle

Classification of artifacts on basis of appearance : Cause : Partial volume averaging ; beam hardening; spiral/helical scanning; scatter radiation; off-focal radiation; incomplete projections

Shading

What is the purpose of the use of bowtie filters in CT?

Shape the beam intensity

Which of the following types of gonadal shielding provide maximal gonadal protection for a male patient when AP, oblique, and lateral projections are obtained?

Shaped contact shield containing 1 mm of lead

In what situation would overlapping reconstructions for subsequent image rendering not be indicated?

Slice thickness= 0.5mm, DFOV = 25

Describes the scanners ability to resolve closely placed objects that are significantly different from their background

Spatial resolution

Maximizing this is important when you are imaging edges of bones, fractures of bones, bone metastasis, tumor margins, free air, and diseases of the lung structure

Spatial resolution

the ability to distinguish details in objects of different densities a small distance apart

Spatial resolution

Which is NOT a sysnonym for the preliminary (localizer) image taken at the start of a CT exam?

Spiral

What instrument can be calibrated to read air kerma?

Standard, or free-air, ionization chamber

The artifact above is caused by aneurysm clips. What type of artifact is this known as?

Streaking

Voluntary and involuntary motion of the patient during CT scanning results in the appearance of ____ artifacts on the image

Streaks

Classification of artifacts on basis of appearance : Cause : improper sampling of data ; partial volume averaging , patient motion ; metal; beam hardening ; noise ; spiral/helical scanning ; mechanical failure

Streaks and bands

Refers to the confusion contributed by overlaying structures superimposed on the tissue of interest. This is largely eliminated by sectional imaging technique

Structural noise

Which type of stroke is usually caused by the rupture of an aneurysm.

Subarachnoid hemorrhagic

CT data acquisition of the foot and ankle can be obtained in a number of different imaging plane

T or F Along with magnetic resonance imaging, CT is a major method for the evaluation of musculoskeletal anatomy and disease

T or F For abdominopelvic scanning, patients are asked to hold their breath during data acquisition

T or F HRCT of the chest is used for the assessment of lung parenchyma in patients with diffuse lung disease such as fibrosis and emphysema

T or F Improvements in the design of CT systems allow successful imaging of the total joint prosthesis and the soft tissues around them

T or F In a jaundiced patient, noncontrast scans through the area of the common bile duct may allow visualization of common bile duct calculi

T or F Most thoracic protocols are performed while the patient lies in a supine position on the scan table with the arms elevated above the head

T or F PET may demonstrate pathologic changes before they would be revealed by modalities like CT or MRI

T or F The administration of IV contrast media for a CT chest scan is dependent on the clinical indication and the preference of the radiologist

Which statement is not true about transient ischemic attacks (TIAs)?

TIAs are an irreversible episode of focal neurologic dysfunction.

The interscan delay inherent in an axial scan method is caused by which factor?

Table movement between data acquisitions

What staffing problem is caused by the evolution of hybrid PET/CT scanners?

Technologists are very rarely trained in both modalities.

Which does not cause asymmetry in the salivary gland during FDG imaging?

Teeth grinding

What is low-contrast resolution?

The ability of the system to differentiate between objects with similar densities.

Which is a TRUE statement about beam hardening?

The beam is hardened more by bone and less by fat

Which statement is true?

The higher the mAs setting, the longer the time between scans.

How would we expect metal to affect the appearance of a localizer image?

The metal object will be represented by high CT numbers and there will be no streaks

Which is a drawback to using sequential CT scanning for intervention procedures?

The procedure can be lengthy.

What is a good example of a high contrast region?

The temporal bone region

Which is a disadvantage to using MDCT in the diagnosis of pulmonary emboli?

The visualization of smaller arteries can be affected by problems with technique or suboptimal vessel opacification.

Which of the following is a TRUE statement regarding MPR's?

They can be created either at the operator's console or at a separate workstation

A volumetric HRCT study refers to a protocol that includes which of the following?

Thin sections, in a helical mode, taken contiguously so as to cover the entire lung, during inspiration, with the patient in a supine position

Which technology do multi-row detector scanners employ?

Third generation

Which type of stroke occurs when a clot that forms as the result of atherosclerosis blocks an artery that supplies blood to the brain.

Thrombotic

At a particular institution, the PE protocol includes a second scan series, performed 180 seconds after the IV contrast injection, that extends from the iliac crests to the knees. What is the purpose of this second series?

To check the pelvis and lower extremities for deep vein thrombosis.

What is the goal in performing perfusion studies for patients with acute stroke?

To distinguish infarcted tissue from the penumbra

Why do many protocols for the evaluation of PE scan in the caudal-to-cranial directions?

To reduce artifacts attributable to patient motion and contrast injection

A patient is being positioned for a routine scan of the brain. Why is he asked to tuck his chin down toward his chest?

To reduce the radiation exposure to the lens of the eyes

Why is multiple image display often used?

To save film

Why is not a reason patients are given nitroglycerin sublingually before coronary CT examinations?

To temporarily lower the patient's heart rate

Which of the following is a low-attenutation structure?

Trachea

Abdominal ultrasonography to evaluate right lower quadrant or pelvic pain is particularly suited to which group?

children

What heart valve is located between the right atrium and the right ventricle?

Tricuspid

Which heart valve has three folds and is in the right side of the heart, between the right atrium and the right ventricle?

Tricuspid

A large WW means a long gray scale.

True

CT fluoroscopy (CTF) capabilities are not standard on scanners. (True or False)

True

CT fluoroscopy is a clinical tool allowing the reconstruction and display of images in real time with variable frame rates.

True

Computed tomographic colonoscopy is an integral tool for the examination of colorectal polyp detection.

True

Digital image processing was first developed for NASA's work in lunar and planetary exploration.

True

The created multiplanar reconstruction images are poorer in quality than the obtained transaxial images.

True

True or False. Aliasing results in an artifact that appears as a moiré pattern in the image.

True

True or False. An algorithm is a set of rules for solving a problem.

True

20-30%

about what percent of stroke victims do not survive?

True or False. In CT, artifacts can arise from a number of sources, including the patient, inappropriate selection of protocols, reconstruction process, and problems relating to the equipment.

True

True or False. In SR, surface formation is the first step, and it involves the operation of contouring.

True

True or False. Low-contrast resolution can be measured with phantoms that contain low-contrast objects of different sizes.

True

True or False. Stochastic effects are those effects for which the probability of the effect occurring depends on the dose.

True

True or False. The method suggested by the Center for Devices and Radiological Health for CT dose measurement is the pencil ionization chamber.

True

True or False. The output digital image must first be converted into an analog signal.

True

True or False. The signals that leave the CT detectors are subject to preprocessing.

True

True or False. When the WL is centered on the lungs, the image display is optimized for the lungs.

True

True or False: Conversion of the attenuation readings into a CT image is accomplished by reconstruction algorithms.

True

True or False? Because of the dense bone of the skull, beam-hardening artifact is common in the posterior fossa.

True

True or False? HRCT of the chest is used for the assessment of lung parenchyma in patients with diffuse lung disease such as fibrosis and emphysema.

True

True or False? HRCT protocols are routinely obtained at full inspiration.

True

True or False? Most thoracic protocols are performed while the patient lies in a supine position on the scan table with the arms elevated above the head.

True

True or False? The location and extent of the ischemic lesion, combined with the severity of the blood flow reduction, are the main factors that predict outcome in the treatment of stroke.

True

True or False? Unless contraindicated, IV contrast media is used when scanning the neck.

True

or False? Routine studies of the abdomen must include the costodiaphragmatic recesses of the lungs.

True

10%

about what percent of the general population has a ramus intermedius artery?

Which is not a technical parameters used for CT imaging of the airways?

Use of thick sections

Which helps to reduce artifacts created by respiratory motion?

Using the shortest scan time possible

What technique is used to virtually unroll, slice open, and display a 3D model of the colon?

Virtual dissection

Which has become the favored 3D imaging technique in CT?

Volume rendering

On the basis of attenuation two points are defined precisely on the CT scale . What are they

Water (0) and air (-1000)

When is the bladder best appreciated on CT?

When 100% filled with urine

When is an increase in endometrial FDG uptake associated with malignancy?

When it occurs in post-menopausal women

Gonadocorticoids

Which are secreted by the innermost region of the adrenal cortex?

Middle-aged people

Which group is most prone to kidney stones?

It is relatively expensive when compared to other methods.

Which is a drawback of using noncontrast helical CT (NCHCT) to diagnose ureteral calculi?

c shape

Which is a not a possible shape of the adrenal glands on a cross-sectional image?

Which network topology is shown in the diagram? A) Bus B) Tree C) Star D) Ring

How are most protocols of the abdomen and pelvis performed?

While the patient lies in a supine position on the scan table with the arms elevated above the head

Who discovered x-rays on November 8, 1895?

Wilhelm Conrad Roentgen

Which of the following are not categories of three-dimensional rendering?

Windowing

All of the following apply to computed tomography (CT) except: A. A computer is used to reconstruct cross-sectional images of the patient B. Mathematical methods are used to reconstruct images C. X-ray film is used as the detector D. Special detectors are used to detect x-rays that have passed through the patient at multiple angles

X-ray film is used as the detector.

Which of the following types of ionizing radiation produce virtually the same biologic effect in body tissue for equal absorbed doses?

X-rays, beta particles, and gamma rays

benign

adrenal lesions tend to grow slowly.

Reducing the DFOV is referred to as

Zooming or targeting

CT arthrography

__________ is useful for evaluation of the joint capsule and intrascapular structures and for finding loose bodies within the joint

minimum gantry rotation time needed for CT coronary calcium screenings

a 4 detector row scanner with 0.5 second gantry rotation time

computer-aided design

a CAD file is a:

pancreas

a CT scan of the abdomen is shown in the image. what does number 23 point to?

left external iliac vein

a CT scan of the abdomen is shown in the image. what does number 3 point to?

coccyx

a CT scan of the abdomen is shown in the image. what does number 7 point to?

hemiazygos vein

a CT scan of the abdomen is shown in the image. what does number 9 point to?

aorta

a CT scan of the abdomen is shown in the image. what is the region represented by number 7?

frontal sinus

a CT scan of the brain is shown in the image. What does number 1 point to?

nasal bones

a CT scan of the brain is shown in the image. What does number 1 point to?

temporal lobe

a CT scan of the brain is shown in the image. What is the region represented by number 5?

medulla oblongata

a CT scan of the brain is shown in the image. What is the region represented by number 6?

false

a CT scan of the chest is shown in the image. number 9 is the left lower lobe of the lung

trachea

a CT scan of the chest is shown in the image. what does number 13 point to?

left pulmonary artery

a CT scan of the chest is shown in the image. what is the region represented by number 14?

ascending aorta

a CT scan of the chest is shown in the image. what is the region represented by number 3?

left atrium

a CT scan of the chest is shown in the image. what is the region represented by number 4?

fibula, lateral malleolus

a CT scan of the left foot is in the image. What is the region represented by number 3?

calcaneus

a CT scan of the left foot is shown in the image. what is the region represented by number 6?

talus

a CT scan of the left foot is shown in the image. what is the region represented by the number 2?

femoral neck

a CT scan of the left hip is shown in the image. What is the region represented by number 3?

pubis

a CT scan of the left hip is shown in the image. What is the region represented by number 9?

gluteus maximus muscle

a CT scan of the left hip is shown in the image. what is the region represented by number 10?

adductor brevis muscle

a CT scan of the left hip is shown in the image. what is the region represented by number 1?

femoral head

a CT scan of the left hip is shown in the image. what region is represented by number 3?

medial femoral condyle

a CT scan of the left knee is shown in the image. What region is represented by number 7?

capitate

a CT scan of the right wrist is shown in the image. what is the region represented by number 4?

hard palate

a CT scan of the sinuses on the coronal plane is shown in the image. What does number 9 point to?

masseter muscle

a CT scan of the sinuses on the coronal plane is shown in the image. What is the region represented by number 6?

mandible

a CT scan of the sinuses on the coronal plane is shown in the image. what does number 7 point to?

kidneys

a CT scan of the spine is shown in the image. What is the region represented by number 11?

aorta

a CT scan of the spine is shown in the image. What is the region represented by number 1?

dural sac

a CT scan of the spine is shown in the image. What is the region represented by number 5?

200 mg/dL

a PET study's sensitivity could be limited if the patient blood sugar level is more than how many mg/dL before the injection of FDG?

200 mg/dL

a PET study's sensitivity could be limited if the patients blood sugar level is more than how many mg/dL before injection of FDG?

A histogram in digital image processing is:

a plot of the number of pixels as a function of the number of gray levels.

An algorithm is:

a set of logical or mathematical instructions

Which is not a technical parameters used for CT imaging of the airways? Select one: a. Use of thick sections b. A fast acquisition that allows the entire lungs to be scanned during a single breath-hold c. Use of post-processing techniques d. Optimal spatial resolution

a. Use of thick sections

16 detector

according to the ACR, what is the minimum CT scanner required for low dose CT lung screening

volumetric HRCT does what ?

acquires the entire lung in helical mode

In order for an X-ray photon to be measured it must: 1. enter the detector chamber 2. be absorbed by the detector material 3. be converted to a measurable event

all of the above

The slip ring on the continuous rotation CT scanners: 1. prevents the high voltage cable from winding up 2. allows the exam to commence more rapidly 3. eliminates the need for the reversal of gantry frame rotation

all of the above

The system console may include: 1. monitor 2. keyboard 3. graphic input device

all of the above

X-ray photons are produced by a fast-moving electron: 1. colliding with an atomic nucleus 2. passing close to an atomic nucleus 3. colliding with an electron within an atom and ejecting it

all of the above

All of the following are key aspects of a quality assurance program EXCEPT:

all tests must be completed by a medical physicist

A term that is synonymous with epilation is

alopecia

Software modules for CT scanners allow each of the following except:

alternate analog signals into digital.

Tube arcing might cause _________ on the images.

an increased appearance of noise

Which component of the CT system converts the electric signal supplied by the detectors into a digital format?

analog to digital converter

Blame decreases the patient's level of self-confidence and, most often, results in the patient responding with___or defensiveness.

anger

The essential concept underlying radiation protection is that

any organ in the human body is vulnerable to damage from exposure to ionizing radiation.

30-60 minutes

approximately how long after the intravenous FDG injection is placed on the examination table?

The process of saving image data from the originating modality to an electronic medium is called ___

archiving

Compared with conventional radographic images, CT localizer images

are slightly poorer image quality

Which of the following is a component NOT normally located in the gantry of a modern CT system?

array processor

The following are accessories for a CT scanner except:

array processor.

what does short scan time decrease?

artifacts from respiratory motion

at what age does bowel activity decrease?

The symbol Z indicates

atomic number of an atom

Adjacent tissues must have different___to be distinguishable on a CT image.

attenuation

Studies showed that postpartum patients treated with ionizing radiation for relief of mastitis are a group of individuals in whom the results of radiation exposure to healthy breast tissue via scattered radiation indicate that radiation

can cause breast cancer

The amount of data that can be transmitted between two points in the network in a set period of time is known as

bandwidth

Which of the following would result in the filter at the aperture of the x-ray tube removed even more low energy x-ray photons?

beam hardening artifact would decrease

for cardiac CT, what is used to reduce the heart rate?

beta blockers: to bring the heart rate to 65-70 bpm

65-70 bpm

beta-blockers are used as part of a CT cardiac protocol to lower the heart rate to less than how many beats per minute (bpm)?

If the range of Hounsfield numbers on the image is 100 to 300, a value of 150 will display as what color?

black

The "pressure exerted by circulating blood on the walls of the vessels" is the the definition of ___

blood pressure

Visual communication is often called___language.

body

Iterative reconstruction algorithms have proven beneficial in dose reduction in each of these CT exams except:

brain perfusion imaging.

Attempts have been made to measure chromosome aberrations after diagnostic x-ray imaging procedures

but successful results have not been achieved in these studies.

Which is part of the scanning step in cardiac CT imaging? Select one: a. Have the patient position arms so they are straight and do not impede the flow of contrast material. b. Connect the ECG leads. c. Load the dual-injector heads with saline and iodinated contrast material. d. If ordered, administer nitroglycerin.

c. Load the dual-injector heads with saline and iodinated contrast material.

The human body can incorporate radium into bone because it is chemically similar to

calcium

The main purpose of the detector is to:

capture x-ray photons and convert them to a measurable signal

If a person receives radiation exposure sufficient to cause the gastrointestinal syndrome, fatality occurs primarily because of

catastrophic damage to the epithelial cells that line the gastrointestinal track, resulting in the death of the exposed person within 3 to 5 days from a combination of infection, fluid loss, and electrolytic imbalance.

how are PE's scanned and why?

caudal-to-cranial to decrease the respiratory effect

The cell components that contain the centrioles are the

centrosomes

Which of the following is NOT a part of the CT Tube?

collimator

For C-arm devices with similar fields of view, the dose rate to personnel located within a meter of the patient is

comparable to that of routine fluoroscopy.

Noise that May occur as a result of approximations used in the measurement and averaging process and in lack of exact geometrical coordination between the oblique, diverging rays and the positions of the pixels

computational noise

Sectional images are obtained from all of the following except: A. tomography. B. transverse axial tomography. C. conventional radiography. D. computed tomography (CT).

conventional radiography

The process of applying a filter function to an attentuation profile is known as:

convolution

The computers that are intigral to the funtioning of the PACS are referred to as

core servers

Which is typically not displayed in color on the display monitor?

cross sectional images

A water phantom is scanned and several ROI's are placed in the resulting image. The ROI's placed at the parimeter of the image measure differently from the ROI's near the center. This idicates a problem with

cross-field uniformity

What can be done to improve the linearity of a CT system?

daily calibrations

The systematic method of collecting data from the patient is called:

data acquisition.

what will applying a high-pass filter do to low contrast resolution?

decrease low-contrast resolution

All these elements can be used during data acquisition to reduce patient dose except: A. combined applications. B. ultrafast ceramic (UFC) detectors. C. decreased pitch. D. online dose modulation.

decreased pitch

Which of the following would reduce the partial volume effect?

decreased slice thickness

Scatter radiation is caused by:

deflections from the original trajectory of an X-ray photon through the patient

Contrast agents fill a structure with a material that has a different___than that of the structure.

density

All of the following are major elements of a typical 3D imaging system except:

detector array.

The computer system for CT includes all of the following except:

detector electronics

Regarding the detectors in the CT system, goemetric efficiency is controlled primarily by

detector spacing and aperature

All of the following are major systems in the basic equipment configuration for computed tomography (CT) except:

dictation system

What device changes the image on the monitor to film?

digital-to-analog converter

For the CT of the foot, when the patient is positioned with the toes pointing straight up, data are acquired in the _______ plane.

direct axial

The Reconstruction FOV is sometimes called the

display FOV or DFOV

what 3 things are critical to CTA exams?

dose, rate and timing

When in the anatomic position, the arms are:

down by sides, palms facing forward

true

drugs may be 3D printed in the future to make time release more accurate

4-10 days

during which days in the life of an intracranial hemorrhage (ICH) is it likely to contain a hyperdense center surrounded by concentric areas of hyperdense and hypodense tissue

4-10 days

during which days in the life of an intracranial hemorrhage (ICH) is it likely to contain a hyperdense center surrounded by concentric areas of hyperdense and hypodense tissue?

A(n) __________ artifact is a streak artifact which arises from a high spatial frequency interface between two tisses with a great difference in density.

edge gradient

Effective mAs can be described as:

effective mAs = true mAs/pitch.

The adrenal glands are part of the

endocrine system

false

Which of the following may be the cause of two parellel lines seen on a localizer image?

faulty detector elements

Neutrophils play an important role in

fighting infection.

Which is an advantage of filtering the Xray beam?

filtering reduces the radiation dose to the patient

___questions allow you to get directly to the relevant points and reduce rambling explanations from the patient.

focused

the entire forefoot (metatarsals and phalanges)

for CT of the ankle, the display field of view (DFOV) does not need to include which of the following?

oblique coronal

for CT of the foot, when the patient is positioned with the knees bent, feet flat on the scan table, and the gantry is angled perpendicular to the subtalar joint, data are acquired directly in which plane?

axial

for CT of the foot, when the patient is positioned with the toes pointing straight up, data are acquired in what plane?

22-cm

for most patients, it is possible to scan both ankles simultaneously within what DFOV?

bony abnormalities of the spine

for which condition of the spine is CT considered superior to MRI?

evaluating a scaphoid fracture

for which of the following is intravenous (IV) contrast medium not necessary or helpful?

neck

for which protocol is the split bolus technique for contrast administration typically used?

The opening in the gantry in which the patient is positioned during scanning is called the:

gantry aperture

In CT, enhancement falls into the two main categories of intravascular and ___

gastrointestinal

What is the unit of the CTDI?

gray

The ability of the tube to withstand by-product heat is called:

heat capacity

how is data obtained in retrospective ECG gating?

helical data acquired throughout the cardiac cycle

drawback of retrospective ECG gating?

high radiation dose

Moist and dry desquamation can be caused by

high radiation doses

Tungsten is used as the target material on the tube's anode because it has a ______ atomic number and a ______ melting point.

high, high

Blood pressure that is abnormally high is referred to as ____

hypertension

Which of the following may reduce the out-of-field artifact?

increasing the scan field of view

A limitation of scanner created MPR's is?

in most cases only straight sagittal and coronal images can be automatically generated

be between 55 and 77 years old have a history of heavy cigarette use

in order for a patient to be eligible for reimbursement for a preventative CT lung scan by medicare and most health insurance companies, the patient must:

2013

in what year was FDA approval given for the first 3D printed skull implant?

CT is so frequently used in the diagnosis of abdominal symptoms and disorders, it often uncovers unsuspected adrenal masses. Researchers have coined the term ---------to describe this mass

incidentalomas

Compton scattering is synonymous with

incoherent scattering

An increase of matrix size (with no change in field of view (FOV)) will ____________ detail.

increase

Reducing the field size to the anatomic features of interest not only reduces patient exposure, but also

increases recorded image quality by decreasing scatter.

HRCT protocols may include three series of scans: inspiratory supine, expiratory supine, and ____________.

inspiratory prone

HRCT protocols may include three series of scans:

inspiratory proneinspiratory supine, expiratory supine, and

A digital image:

is a numerical representation of an object.

Collimation:

is accomplished by physically blocking x-rays

300 mAs

is the patient is supine on the table with his arm resting on the belly during a CT examination wrist, tube current must be increased to at least how many mAs?

3 notes on ECG pulsed tube current modulation

it decreases tube current during the systolic phase; it helps decrease overall dose; it cannot be used with patients that have arrhythmia

What technical factor determines the penetrating power of the photons coming from the X-ray tube?

kVp

This figure is that of a:

line pairs phantom

CT number uniformity can be affected by all of the following factors except:

linearity.

A large WW indicates that there is a relatively ______________ gray scale.

long

To assess the magnitude and severity of late effects on the exposed population from the 1986 nuclear power station accident at Chernobyl

long-term follow-up studies are necessary.

To assess the magnitude and severity of late effects on the exposed population from the 1986 nuclear power station accident at Chernobyl A. follow-up is not necessary because the radiation received by the entire exposed population was fatal. B. minimal follow-up is only necessary because the exposed population did not receive sufficient radiation exposure to cause severe late effects. C. short-term follow-up studies are necessary. D. long-term follow-up studies are necessary.

long-term follow-up studies are necessary.

a scheme that compresses an image without any loss of information when the image is decompressed is called

lossless

Which is a characteristic of Xenon gas?

low efficiency

the smallest object that can be visualized at a given contrast level and dose

low-contrast detectability

The ability of a system to differentiate, on the image, objects with similar densities is known as:

low-contrast resolution

Most pulmonary emboli are caused from thrombi originating in the __________ known as deep vein thrombosis (DVT).

lower extremities

a big plus for prospective ECG triggering?

lower radiation dose

Antibodies are protein molecules produced by specialized cells in the bone marrow called

lymphocytes.

The number of electrons that flow from the cathode to the anode in the tube is controlled by the :

Which technique factor determines the quantity of photons (dose) incident on the patient for the duration of the exposure?

mAs

When CTF is used it is very important that CTF exposure time and _______ be kept as low as possible.

All of the following factors affect in-plane spatial resolution except: 1) focal spot size. 2) detector cell size. 3) sampling frequency. 4) magnification.

magnification.

Describe the relationship between magnitude and frequency (lp/cm)

magnitude reduces as the frequency of bar pattern increases

When a properly calibrated automatic exposure control (AEC) is not employed to obtain a uniform selection of technical x-ray exposure factors, well-managed imaging departments

make use of standardized technique charts that have been established for each x-ray unit in that facility.

What is it called when a patient breathes differently with each data acquisition and areas of anatomy seem to be misplaced in the Z axis?

misregistration

a quantitative measure of the ability of an imaging system to reproduce patterns that vary in spatial frequency useful in predicting image degradation in a series of radiographic components

modulation transfer function

platelet count

most laboratory evaluations for CT guided biopsy procedures include prothrombin time, partial thromboplastin time, and ________________

platelet count

most laboratory evaluations for CT-guided biopsy procedures include prothrombin time, partial thromboplastin time and ________________

platelet count

most laboratory evaluations for CT-guided biopsy procedures include prothrombin time, partial thromboplastin time, and ____________

platelet count

most laboratory evaluations for CT-guided biopsy procedures include prothrombin time, partial thromboplastin time, and _______________

false

most medical use objects can be printed in minutes if not seconds

adrenal masses cause enlargement of the adrenal gland but no significant increased hormone production

nonfunctioning

The much smaller structures that make up nucleic acids are called

nucleotides

how is airway imaging done?

on inspiration and expiration

How many CT numbers are assigned to each pixel in the image matrix?

one

The property of intravascular contrast media that refers to the number of particles in solution, per unit liquid, as compared with blood is called ___

osmolality

A device that is used to automatically load and unload optical discs is called

optical jukebox

The heart is enclosed in a loose-fitting, double-layered sac called the

pericardium

The heart is enclosed in a loose-fitting, double-layered sac called the ________.

pericardium

In which direction are the streaks from the edge gradient effect oriented?

parallel to the direction of the sharp density difference interface

Which is not a scanning parameter?

patient size

ß-Blockers are likely to be used as part of a cardiac CT protocol when the

patient's heat rate is higher than 65 bpm

10%

pheochromocytoma are malignant in about what percent of cases?

Each 2-dimensional square of data tht make up the CT image is called a

pixel

The contraction for "picture element" is:

pixel

The least complicated and most frequently used image processing technique is the:

point operation.

Gray-level mapping belongs to the class of:

point processing technique.

How often is the accurracy of the scanner's slice thickness tested?

semiannually

An imaging technique that attempts to acquire data only during cardiac segments with the lowest cardiac motion is called

prospective ECG triggering

A___defines a common set of rules and signals that computers on the network use to communicate.

protocol

If a patient's systolic blood pressure is less than 90 mm Hg, the__pulse will not be palpable.

radial

What quality control test must be performed by a medical physicist?

radiation dose measurements

Which of the following would eliminate ring artifact?

recalibration of the detector elements

refers to the diameter of the reconstructed area in millimeters or centimeters covered by the image

reconstruction FOV

All of the following can be described as image quality parameters except:

reconstruction parameters.

All of the following can be described as image quality parameters except: A. high-contrast spatial resolution B. low-contrast spatial resolution C. noise D. reconstruction parameters

reconstruction parameters.

CT overcomes the limitations of radiography and conventional tomography by achieving all of the following except:

reducing a patient's radiation dose.

When a prediction is made that the number of excess cancers rises as the natural incidence of cancer increases with advancing age in the population, the risk is considered to be

relative.

If bone marrow cells have not been destroyed by exposure to ionizing radiation, they can:

repopulate after a period of recovery

The ___is the number of breaths a person takes per minute. (two words)

respiratory rate

Which is not a type of device used to display CT images?

scanner

The imaging system components are located in the:

scanner room

The process of dividing a picture into small regions called pixels is referred to as:

scanning.

The process of selectively removing or isolating information from the 3D data set is referred to as

segmentation

____distance is suitable for business discussions and conversations at social gatherings.

social

Assume the raw data are still available. In what scenario would it be impossible to create an MPR?

source images vary in gantry tilt

Which is not another name for reconstruction algorithm?

spatial frequency algorithm

Describes the scanner's ability to resolve closely placed objects that are significantly different from their background

spatial resolution

what does the term 'in-plane' refer to in spatial resolution?

spatial resolution measured in the axial plane (x-y plane

false

surgical training is preferable wit cadavers versus 3D printing because cadavers are easier and cheaper to obtain?

___communication cues involve the use of touch to impart meaning.

tactile

what 2 things have made cardiac CT comparable to conventional coronary catheter angiography?

temporal and spatial resolution improvements

2-2.5

the SUV of the liver should be in what range?

1.5-2

the SUV of the mediastinal blood pool should be in what range?

The x-ray beam sources for CT produce x-ray energy that is polychromatic. This means that :

the beam comprises photons with varying energies

What is the cause for the 'cupping' artifact

the body hardens the beam thus increasing the attenuation numbers in the center

what is the R-R interval?

the distance between the 2 R waves in an ECG

What control does the Tech have over the X-rays during a CT Exam?

the energy level and the quantity of the X-rays

false

the image shown is of the left wrist?

coronary circulation refers to what?

the movement of blood thru the tissues of the heart

The design that incorporates the high-voltage generator on the rotating frame of the CT gantry eliminates:

the need for long high-tension cables.

the overall complication rate for a fine-needle biopsy is approximately what percent?

Which is NOT true of an LCD monitor?

the purchase price of an LCD is approximately half that of a CRT

what triggers the axial mode image acquisition in prospective ECG?

the signal from the R wave

The origin of digital image processing stems from:

the space program

what does the pulmonary artery follow closely?

the subdivision of the bronchial tree

What are the key aspects of the axial method of data acquisition?

the table remains stationary while the xray tube rotates within the gantry, collecting data

What is the cause for the cupping artifact?

the tissues of the body attenuate low energy photons

What is the cause of cone beam artifacts?

the use of a standard filtered back projection reconstruction when the X-ray beam is more than 20mm thick

There are several influencing factors on subject contrast. what are they

thickness, mass density, atomic number, and incident photon energy

Which of the following will have the least likelihood of producing edge gradient artifacts?

thin slices with a full scan

Partial volume artifacts can be reduced with _____________ slice acquisitions and computer algorithms.

thinner

Partial volume artifacts can be reduced with

thinner slice acquisitions and computer algorithms

The _______ has the highest intrinsic natural contrast of any body part.

thorax

has the highest intrinsic natural contrast of any body part.

thorax

Which of the following components is NOT housed within the gantry?

three phase generator

Deterministic effects follow a:

threshold dose.

The formation, development, or existence of a clot within the vascular system is referred to as

thrombosis

The formation, development, or existence of a clot within the vascular system is referred to as ___________.

thrombosis

why are gated exams used in cardiac CT?

to acquire images during periods of lower cardiac motion

to be effective, tissue plasminogen activator (t-PA) must be administered within how many hours of the first signs of stroke?

Stochastic effects are those effects for which the probability of the effect occurring depends on the dose. 1) True 2) False

true

The method suggested by the Center for Devices and Radiological Health for CT dose measurement is the pencil ionization chamber. 1) True 2) False

true

CT fluoroscopy

two different imaging techniques are used for CT-guided interventions: sequential CT and ___________

DICOM refers to a

universally adopted standard for medical image interchange

true

unless contraindicated, IV contrast media is used when scanning the neck

Limitations of maximum intensity projections include each of the following except:

uses large amounts of data in the 3D space.

Decreasing scan time:

usually decreases motion artifacts, but sometimes increases motion artifacts

drawbacks to ECG triggering

very sensitive to cardiac motion artifacts and image misregistration, especially in pt.s with irregular heartbeat

In CT image creation using a third generation design, a complete set of ray sums is known as a __________

view

A physical property that may be described as the thickness or friction of the fluid as it flows is called ____

viscosity

The best early indicators of a physiologic change in a patient are __ (two words)

vital signs

Pixels in a digital image representing information contained in a volume of tissue in the patient are referred to as a:

voxel

CT-guided biopsy

what are the most common interventional procedures

CT-guided biopsies

what are the most common interventional procedures?

to temporarily lower the patient heart rate

what is not a reason patients are given nitroglycerin sublingually before coronary CT examinations?

25%

what is the lifetime rate of appendectomy for women if incidental appendectomies are included?

.STL

what is the most common file format used to 3D print after conversion from medical images?

completed stroke

what is the preferred medical term used to describe an acute episode of interrupted blood flow to the brain that lasts longer than 24 hours?

pneumothorax

what is the primary complication of CT-guided lung biopsies?

bleeding

what is the primary complication of all types of biopsy procedures?

MRI

what is the primary modality for the evaluation of internal derangement of the knee?

stroke in evolution

what is the term used to describe a time limited event in which the neurologic deficits occur in a progressive pattern?

1.25 mm

what is the typical slice thickness for studies of the head?

at end-diastole

what is typically the point of the cardiac cycle with the least cardiac motion?

50-70%

what percent of total energy is obtained from the oxidation of fatty acids

80-85%

what percent of urinary calculi is thought to pass spontaneously?

lower the shoulders as much as possible

what should the patient be asked to do during a CT scan of the neck to reduce artifacts that degrade images in the lower neck?

technologists are very rarely trained in both modalities

what staffing problem is caused by the evolution of hybrid PET/CT scanners?

hypotensive

what type of stroke occurs as a result of blood pressure that is to low?

between 5 and 10 minutes after administration

when does the peak effect of IV-push metoprolol occur?

when it occurs in post-menopausal women

when is an increase in endometrial FDG uptake associated with malignancy?

Particles associated with electromagnetic radiation that have neither mass nor electric charge are

x-ray photons.

What is the process by which additional rotations before and after the planned length are taken?

Final 1f

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