MOSBY ONLINE FLASHCARDS!
(110 cards)
1
Q
The rights of the patient include which of the following?
1. The patient has the right to considerate and respectful care.
2. The patient has the right to receive a copy of the diagnostic procedure performed.
3. The patient has the right to refuse medical treatment.
A
1 and 3 only.
2
Q
A patient is required to have the following radiographic examinations, CT of the abdomen, GI series, and a barium enema. The correct order for the scheduling of these procedures would be:
A
- CT of the abdomen.
- Barium enema.
- GI series.
3
Q
The patient is not required to give informed consent for which of the following CT studies?
A. Noncontrast brain to r/o subdural hematoma.
B. CT-guided abscess for drainage.
C. Stereotactic biopsy of a cranial tumor.
D. CTA chest for a PE.
A
A. Noncontrast brain to r/o subdural hematoma.
4
Q
The normal pulse rate range for a child is:
A
70 to 120 beats per minute.
5
Q
The average range for normal prothrombin (PT) time is approximately:
A
12 to 15 seconds.
6
Q
The normal platelet count range for an adult is:
A
140,000 to 440,000/uL of blood.
7
Q
The normal range for systolic blood pressure in an adult is:
A. 40 to 60 mm Hg.
B. 60 to 90 mm Hg.
C. 80 to 120 mm Hg.
D. 95 to 140 mm Hg.
A
D. 95 to 140 mm Hg.
8
Q
Which of the following is a normal stage of the cardiac cycle?
1. Atrial systole.
2. Ventricular systole.
3. Atrial fibrillation.
A
1 and 2 only.
9
Q
The assessment of D dimer is used to diagnose which pathological conditions?
A
PE and DVT.
10
Q
Creatinine clearance, or the rate at which creatinine is filtered from the bloodstream, may be used to approximate:
A
GFR.
11
Q
As related to the cardiac cycle, the term __________ refers to the contraction of heart muscle.
A
Systole.
12
Q
Which of the following corresponds to the period of the cardiac cycle known as ventricular systole?
A
Contraction of the left and right ventricles.
13
Q
Which of the following corresponds to the period of the cardiac cycle known as atrial systole?
A
Contraction of the left and right atria.
14
Q
Which of the following refers to the period of the cardiac cycle known as complete cardiac diastole?
1. Contraction of the left and right ventricles
2. Relaxation of the heart muscle
3. The QRS complex of the electrocardiogram (ECG)
A
2 only.
15
Q
Which of the following refers to the period of the cardiac cycle known as complete cardiac diastole?
1. Relaxation of the left and right ventricles
2. Relaxation of the left and right atria
3. The T wave of the electrocardiogram (ECG)
A
1, 2, and 3.
16
Q
Cardiac CT images are typically acquired during which phase of the heart’s cycle?
A
Diastolic phase.
17
Q
Which of the following reduces the scatter radiation reaching the detectors?
A. Post-patient collimation.
B. Pre-patient collimation.
C. Pre-patient collimation.
D. Both a and c.
A
D. Both a and c.
18
Q
Which of the following is the primary interaction between x-ray photons and tissue during computed tomography?
A. Bremsstrahlung.
B. Characteristic.
C. Compton effect.
D. Coherent scatter.
A
C. Compton effect.
19
Q
The assignment of different generations to CT scanners is based on the configuration of the:
A
Tube and detectors.
20
Q
When one is using a third-generation CT scanner, it is important that reference detectors positioned at the peripheral portions of the detector array be exposed to:
A. Homogeneous radiation.
B. Unattenuated radiation.
C. Monochromatic radiation.
D. Remnant radiation.
A
B. Unattenuated radiation.
21
Q
In 1979, the scientists __________ and __________ shared the Nobel Prize for their research in computed tomography.
A
Hounsfield and Cormack.
22
Q
The interaction between x-ray and matter that is responsible for the production of the scatter radiation absorbed by the patient and detectors is:
A
Compton effect.
23
Q
The types of detectors used in computed tomography are:
1. Gas ionization
2. Stimulable phosphor
3. Scintillation
A
1 and 3 only.
24
Q
Which of the following statements concerning the translate-rotate mode of CT data acquisition is/are correct?
1. 360-degree circular detector arrays are used.
2. Data are collected only during translation.
3. Was used in first- and second-generation CT scanners.
A
2 and 3 only.
25
Which of the following technologic advances has led to the development of spiral/helical CT scanning?
1. Slip-ring technology
2. Electron beam technology
3. High-efficiency x-ray tubes
1 and 3 only.
26
For a given CT acquisition, the calculated mAs applied to each reconstructed slice may be referred to as the:
A. Effective mAs.
B. Peak mAs.
C. Absorbed mAs.
D. Constant mAs.
A. Effective mAs.
27
The approximate inherent filtration of the CT x-ray amounts to an aluminum equivalent of:
A. 1.2 mm.
B. 3.0 mm.
C. 5.8 mm.
D. 10.0 mm.
B. 3.0 mm.
28
Which of the following acquisitions may be characterized as noncontiguous?
A. 2.5 mm sections reconstructed every 1.25 mm.
B. 5.0 mm sections reconstructed very 7.5 mm.
C. 3.75 mm sections reconstructed every 3.75 mm.
D. 20-second cine acquisition with 1.25 mm sections.
B. (INTERVAL IS GREATER THAN THE SECTION WIDTH!).
29
Which of the following acquisitions may be characterized as overlapping?
A. 2.5 mm sections reconstructed every 1.25 mm.
B. 5.0 mm sections reconstructed very 7.5 mm.
C. 3.75 mm sections reconstructed every 3.75 mm.
D. 20-second cine acquisition with 1.25 mm sections.
A. (INTERVAL IS LESS THAN SECTION WIDTH!).
30
In multislice CT (MSCT), the beam pitch is equal to the table feed per rotation divided by the:
A. number of detectors.
B. pre-patient collimation.
C. total collimation.
D. number of channels.
C. total collimation.
31
An acquisition is made on a 4-slice MSCT system with a detector array of 16 x 1.25-mm detector elements along the z-axis. With a selected beam width of 20 mm, what beam pitch would result in the table moving 35.00 mm for each rotation of the gantry?
1.75.
The beam pitch for a given acquisition is equal to the table feed per rotation divided by the total collimation. The total collimation for this acquisition is equal to the total number of sections (detectors) multiplied by the detector dimension, or 16 multiplied by 1.25 mm. The beam pitch may be therefore calculated by dividing 35.00 by 20, or 1.75.
32
The number, length, and organization of the individual detector elements in an MSCT system are referred to as the:
A. detector configuration.
B. array pitch.
C. CT generation.
D. detector pitch.
A. detector configuration.
33
The type of MSCT detector array that contains midline narrow elements flanked by wider detectors is called a(n):
A. uniform matrix array.
B. adaptive array.
C. hybrid array.
D. stationary array.
C. hybrid array.
34
A 64-slice MSCT system employs an array of 64 detectors, each with a dimension of 0.625 mm. What beam collimation is required to expose the middle 32 detectors of the array to transmitted x-radiation?
20 mm
The selected detector configuration for a given acquisition determines the necessary beam collimation. The selected 32 detectors, each with an individual dimension of 0.625 mm, would require a beam collimation of 20 mm to expose each to transmitted radiation (32 ✕ 0.625 = 20 mm).
35
The component of the DAS responsible for strengthening the signal emitted from a detector is termed the:
A. DAC.
B. preamplifier.
C. high-resolution comb.
D. bow-tie filter.
B. preamplifier.
36
The process of scanning a phantom device of known density to improve the accuracy of CT attenuation measurement may be referred to as:
A. Hounsfield correction.
B. Linearity.
C. Uniformity.
D. Calibration.
D. Calibration.
37
Which of the following technical parameters would greatly improve the quality of CT studies requiring multiplanar reformation (MPR) images?
A. noncontiguous scans.
B. wide section thicknesses.
C. contiguous scans with wide section thicknesses.
D. overlapping scans with narrow sections.
Answer: D.
38
In 1917, Austrian mathematician __________ proved that it was possible to reconstruct a three-dimensional object from the infinite set of all of its projections.
Radon.
39
Which of the following types of image reconstruction was used in the first prototype CT scanner?
A. Convolution method.
B. Iterative technique.
C. Fourier transform.
D. Back-projection.
B. Iterative technique.
40
During CT angiography, images may be reconstructed using only the greatest density encountered along each ray. This type of specialized CT image is called a(n):
A. 3-D model.
B. volume-rendered image.
C. MIP image.
D. surface-rendered image.
C. MIP image.
41
Which of the following is a typical protocol for a CT study of the brain for a patient with a history of dizziness?
A.10-mm × 10-mm sections from the skull base to the vertex
B. 7-mm × 7-mm sections from the skull base to the posterior fossa
C. 2.5-mm × 2.5-mm sections through the posterior fossa, 5 mm × 5 mm to vertex.
D. 1.5-mm × 1.5-mm sections from skull base to vertex
Answer: C.
42
Which of the following describes the scout (localizer) projection used to prescribe an axial CT acquisition of the brain?
A. Anteroposterior.
B. Submentovertical.
C. Lateral.
D. Posteroanterior.
C. Lateral.
43
Glioma is a general term used to describe a group of primary tumors. Consisting of malignant glial cells, gliomas occur in the:
Brain.
44
Which of the following areas of the head commonly becomes calcified?
1. Thalamus
2. Pineal gland
3. Choroid plexus
2 and 3.
45
Following the injection of intravenous contrast media during a CT examination of the brain, which of the following anatomic areas does not enhance?
A. Anterior communicating artery.
B. Choroid plexus.
C. Posterior horn of lateral ventricle.
D. Dura matter.
C. Posterior horn of lateral ventricle.
46
Which of the following statements regarding the pituitary gland is FALSE?
A. It is sometimes referred to as the hypophysis cerebri.
B. It is seated within the sella turcica.
C. The infundibulum attaches it to the hypothalamus.
D. It is responsible for the production of epinephrine.
Answer: D.
47
Cerebrospinal fluid (CSF) is produced in the:
Choroid plexuses.
48
A stereotactic unit would be used for which of the following specialized CT examinations?
A. CT-guided fine-needle aspiration of an abdominal abscess.
B. 3-D CT angiogram.
C. CT-guided biopsy of the brain.
D. Dual window scanning.
C. CT-guided biopsy of the brain.
49
In which of the following cranial nerves would an acoustic neuroma be found?
A. Third.
B. Eighth.
C. Tenth.
D. Twelfth.
B. Eighth.
50
Which of the following types of pathologic conditions cannot be easily diagnosed from a CT scan of the brain?
A. Astrocytoma.
B. Traumatic hemorrhage.
C. Cerebral infarct.
D. Alzheimer's disease.
D. Alzheimer's disease.
51
In a female patient, gonadal shielding may be applied during which of the following CT examinations?
1. Chest
2. Abdomen
3. Brain
1, 2, and 3.
52
The quantity of radiation dose received by the patient from a series of CT scans is referred to as the:
A. MSAD.
B. XCAL.
C. CTDI.
D. MTF.
A. MSAD.
53
Which of the following technical characteristics of a CT system does NOT directly affect patient dose?
A. Source-to-detector distance.
B. Filtration.
C. Detector efficiency.
D. Filament size.
D. Filament size.
54
Which of the following statements most accurately describes the relationship between slice sensitivity profile (SSP) and dose profile?
A. The SSP is always wider than the dose profile.
B. The SSP is equal in width to the dose profile.
C. The dose profile is always wider than the SSP.
D. The SSP has no effect on the dose profile.
C. The dose profile is always wider than the SSP.
55
The approximate radiation dose measured during a scan of a 100-mm-long pencil ionization chamber is termed the:
A. MSAD.
B. Effective dose.
C. CTDIvol.
D. CTDI100-
D. CTDI100-
56
The calculation of the average cumulative dose to each section within an acquisition of multiple sections is termed the:
A. CTDIw.
B. CTDI100-
C. Kerma.
D. MSAD.
D. MSAD.
57
The multiple-scan average dose (MSAD) is used to describe the:
Average dose to a single section within a scan of multiple sections.
58
Which of the following units is used to quantify absorbed dose?
A. Roentgens (R).
B. Gray (Gy).
C. Sieverts (Sy).
D. Curie (Ci).
B. Gray (Gy).
59
Which of the following units is used to quantify effective dose?
A. Roentgens (R).
B. Gray (Gy).
C. Sieverts (Sy).
D. Curie (Ci).
C. Sieverts (Sy).
60
The interaction between x-radiation and tissue that results in the complete loss of all x-ray photon energy is called:
Photoelectric absorption.
61
Which of the following design characteristics of a CT system would result in an increased radiation dose to the patient?
1. Decreased focus-to-isocenter distance
2. Decreased focus-to-detector distance
3. Decreased filtration
1, 2, and 3.
62
The acronym DLP is used to describe:
The radiation dose to the patient during a CT scan.
63
Which of the following technical factors has a direct effect on patient dose?
A. Kernel.
B. kVp.
C. Window width.
D. DFOV.
B. kVp.
64
Which of the following technical changes would serve to decrease patient radiation dose during a CT examination?
A. Increase matrix size.
B. Increased DFOV.
C. Increased level of tolerated image noise.
D. Increased kVp.
C. Increased level of tolerance image noise.
65
A best practice for the use of in-plane bismuth shielding requires the:
A. shield to be placed above & below the patient.
B. placement of shield before the acquisition of scout (localizer) images.
C. shield to remain outside the scan acquisition range.
D. placement of shield after the acquisition of scout (localizer) images.
Answer: D.
66
The normal range of glomerular filtration rate (GFR) for women is:
60 +/- 10 mL/min/m^2
67
The normal range for the International Normalized Ratio (INR) for prothrombin time (PT) results is:
0.8 to 1.2.
68
The medication known as Coumadin, or its generic name warfarin, is often used to treat:
A. type 2 diabetes.
B. high cholesterol.
C. reactions to iodinated contrast agents.
D. blood clots.
D. blood clots.
69
Which of the following statements is true regarding patients receiving metformin therapy for type 2 diabetes and IV contrast-enhanced CT examinations?
1. Metformin therapy is a direct contraindication to administration of IV contrast agents.
2. The patient should not take metformin for up to 2 days following administration of an IV contrast agent.
3. After administration of an IV contrast agent, the patient may need renal function testing before resuming metformin therapy.
2 and 3 only.
70
The lumens of needles used for the injection of contrast media vary in diameter. The unit used to describe this diameter is called:
A. length.
B. cubic centimeter (cc).
C. gauage.
D. psi.
C. gauage.
71
Advantages of automatic power injectors in comparison with the manual bolus method of intravenous contrast administration include:
1. Increased tissue enhancement because of faster injection times
2. Uniform administration of contrast agent over the entire length of the study
3. Decreased incidence of adverse reaction to contrast agent
1 and 2 only.
72
Which of the following drug administration routes provides the most rapid absorption and action within the body?
A. oral.
B. subcutaneous.
C. intramuscular.
D. intravenous.
D. intravenous.
73
Where should the tourniquet be positioned during preparation of a patient for intravenous contrast administration?
Proximal to the injection site.
74
Which of the following statements concerning site preparation with an antiseptic for an invasive procedure is true?
A. Dab the area with antiseptic-moistened paper towel.
B. Paint the area with antiseptic in a linear motion.
C. Paint the area with antiseptic in a circular motion, beginning at the center and working outward.
D. Paint the area with antiseptic in a circular motion, beginning at the outer margins and working inward
C. Paint the area with antiseptic in a circular motion, beginning at the center and working outward.
75
Which of the following places the listed butterfly needles in decreasing order in terms of bore dimension?
1. 21 gauge.
2. 23 gauge.
3. 19 gauage.
- 19 gauge.
- 21 gauge.
- 23 gauge. -
76
CT images that have been reconstructed from a portion of the data acquisition process in the hopes of reducing patient motion artifacts are called:
A. dynamic images.
B. subtraction images.
C. segmented images.
D. filtered images.
C. segmented images.
77
Which of the following is not an iterative method of CT image reconstruction?
A. Point-by-point correction.
B. Fourier transform.
C. Simultaneous reconstruction.
D. Ray-by-ray correction.
B. Fourier transform.
78
Which of the following manipulations involves the use of image data?
A. Adjusting the width & level of a window setting.
B. Decreasing the DFOV.
C. Changing the algorithm selection.
D. Increasing the matrix size.
A. Adjusting the width and level of a window setting.
79
As a solid-state CT detector measures transmitted radiation, it emits a proportional response in the form of a(n):
Analog signal.
80
During a CT scan, each sample of ray sum measurements made by the data acquisition system (DAS) is called a:
A. signal.
B. view.
C. projection.
D. ray.
B. view.
81
The ability of an object to attenuate the x-ray beam is assigned a value known as the:
Linear attenuation coefficient.
82
Which of the following mathematical techniques is used for the reconstruction of volumetric MDCT images?
A. 180-degree interpolation (180LI).
B. 360-degree interpolation (360LI).
C. Back-projection.
D. Fourier reconstruction.
Answer: A.
83
The primary advantage of an isotropic MDCT data set is:
A. reduced scan time.
B. increased SNR.
C. improved raw data convolution.
D. high-quality MPRs.
D. high-quality MPRs.
84
The technique that allows the user to select the range of pixel values used in a 3-D CT reformation is termed:
Thresholding.
85
What is the dimension of each pixel in the matrix of an image with the following parameters?
FOV = 25.6 cm
Matrix = 512 mm ✕ 512 mm
0.5 mm and 0.05 cm.
the dimension of a pixel may be calculated by dividing the field of view (FOV) by the matrix size. The DFOV, 25.6 cm, must first be converted into 256 mm. This is then divided by 512 mm for a pixel dimension of 0.5 mm. Keep in mind that the pixel is a two-dimensional item, square in shape, and the measurement of 0.5 mm corresponds to only one side. The numerical lengths of 0.5 mm and 0.05 cm are equal.
86
The following formula is used to calculate the linear attenuation coefficient:
I = I0e–μx
The symbol "x" identifies:
Absorber thickness.
87
A voxel may be defined as which of the following?
A. the portion of the CRT displaying the image.
B. a miniature image.
C. a volume element.
D. an arrangement of pixels.
C. a volume element.
88
The portion of the primary beam interacting with a single detector is known as a:
A. ray.
B. view.
C. profile.
D. sample.
A. ray.
89
A pixel may be defined as:
A picture element.
90
In an effort to reduce radiation exposure to the orbits during a CT examination of the brain, the gantry may be angled:
A. perpendicular to the hard palate.
B. parallel to the hard palate.
C. 15 degrees superior to the IOML.
D. 15 degrees inferior to the IOML.
C. 15 degrees superior to the IOML.
91
High-resolution CT examinations of the temporal bones and internal auditory canal should include which of the following technical parameters?
1. 5- to 7-mm section width
2. Small (less than 10 cm) targeted DFOV
3. Soft-tissue kernel
2 only.
92
Which of the following technical parameters is NOT a necessary component of a high-resolution CT examination of the internal auditory canals (IAC)?
A. 1-mm section width.
B. targeted 10-cm DFOV.
C. sagittal MIP images.
D. bone algorithm.
C. sagittal MIP images.
93
Multiplanar reformation (MPR) images along the long axis of the optic nerve would be best described by which of the following anatomic planes?
A. sagittal.
B. coronal.
C. oblique sagittal.
D. oblique coronal.
C. oblique sagittal.
94
Which of the following may be used to reduce metal streak artifact on coronal-plane CT images of the orbits?
1. Retrospective reconstruction of targeted images with reduced display field of view (DFOV)
2. Metallic artifact reduction (MAR) software to improve image quality
3. Construction of coronal multiplanar reformation (MPR) images from the acquired axial-plane images
2 and 3 only.
95
Coronal imaging through the paranasal sinuses is typically performed with the plane of imaging:
A. parallel to the infraorbital-meatal line.
B. perpendicular to the glabellomeatal line.
C. parallel to Reid's baseline.
D. perpendicular to the hard palate.
D. Perpendicular to the hard palate.
96
Which of the following pitch settings would result in the lowest radiation dose to the patient?
A. 1.0
B. 1.2
C. 1.7
D. 2.0
D. 2.0
97
As part of a comprehensive approach to minimize CT radiation exposure to the pediatric patient, the technologist should:
1. Apply out-of-plane lead (or equivalent) shielding to protect radiosensitive tissues.
2. Reduce the technical parameters (e.g., mA, kVp) based upon the patient size/weight.
3. Eliminate unnecessary contrast enhancement phase acquisitions.
1, 2, and 3.
98
Which of the following is the unit of radiation exposure?
A. Roentgen (R).
B. Sieverts (Sv).
C. Becquerel (Bq).
D. Gray (Gy).
A. Roentgen (R).
99
Assuming no other changes are made, which of the following would reduce patient exposure during CT?
A. Decrease the pitch from 1.5 to 1.0.
B. Increase kVp from 100 to 140.
C. Increase the tolerated noise level of the acquired images.
D. Increase the scan field of view (SFOV) from small to large.
Answer: C.
100
The interaction between x-radiation and tissue that results in a reduction in x-ray photon energy with a subsequent change in photon direction is called:
Compton Scatter.
101
Assuming no other technical adjustments are made, an increase in the applied tube potential (kVp) used for a CT acquisition will result in a:
Increased dose length product (DLP).
102
When employing in-plane bismuth shielding, a thin spacer material may be positioned to reduce:
A. streaking artifact.
B. spatial resolution.
C. magnification.
D. patient discomfort.
A. streaking artifact.
103
A dose check system features which of the following?
1. Dose notification
2. Dose alert
3. Dose report
1 and 2 only.
104
Current CT systems employ which of the following image reconstruction methods to reduce patient radiation dose?
A. interpolation.
B. filtered back projection.
C. iterative reconstruction.
D. convoluted reconstruction.
C. iterative reconstruction.
105
Current industry standards require that data related to the tube output during CT acquisition be documented in the RDSR which stands for:
Radiation Dose Structured Report.
106
Assuming no other technical adjustments are made, when the kVp utilized for a given CT acquisition is increased, which of the following occurs?
A. Signal-to-noise ratio
B. Spatial resolution increases
C. Increased patient dose
D. Decreased patient dose
C. Increased patient dose.
107
During CT data acquisition, the section of the patient exposed to radiation may be referred to as the:
1. Slice
2. Dose profile
3. Pitch
1 and 2 only.
108
Which of the following statements regarding CT image noise is TRUE?
A. As the mAs for a given CT acquisition increases, image noise decreases.
B. As the selected DFOV for a CT image decreases, noise decreases.
C. As patient size decreases, noise increases.
D. As patient size decreases, noise decreases.
Answer: D
109
Which of the following describes the system that adjusts the mA setting according to part size variations along the z-axis?
A. Longitudinal tube current modulation
B. Temporal tube current modulation
C. Angular tube current modulation
D. Automated tube voltage selection
A: Longitudinal tube current modulation.
110
Which of the following descriptors accounts for the dose effects of image spacing during axial acquisition?
A. CTDIvol.
B. CTDIw.
C. EfD.
D. MSAD.
D. MSAD.
