Final exam
Which of the following most closely approximates the actual radiation dose to specific dose to a specific patient for a specific exam? a. dose length product (DLP) b. multiple scan average dose (MSAD) c. CTDI
A. DLP
Which of the following medications may be used to treat bradycardia? a. epinephrine b. naloxone c. soluMedrol d. diphenhydramine
A. Epinephrine
Which operation forms the basis for CT reconstruction? A. Fournier transform B. filter-back projection C. Lambert-beer law D. convolution
A. Fournier transform
If extravasation occurs, contrast can be dissipated by reducing its viscosity. This can be accomplished by applying a: a. hot pack. b. cold pack c. sterile bandage. d. peripherally inserted central catheter (PICC) line.
A. Hot pack
Compared to barium used for regular fluoroscopy procedures, the barium used for CT procedures is: a. less dense. b. more dense. c. of the same density.
A. Less dense
Interpolation is directly affected by: A. pitch B. focal spot size C. filtered backprojection D. A and B are correct
A. pitch
The typical kilovolt peak (kVp) range used for CT scans is: a. 90-100. b. 100-120. c. 100-140. d. 120-160.
C. 100-140
The National Council on Radiation Protection and Measurements (NCRP) recommends that the annual occupational dose for imaging professionals not exceed: a. 1 mSv b. 5 mSv c. 50 mSv d. 1 Sv
C. 50 mSv
A smoothing filter is applied to scans that display very: A. Low brightness B. High contrast C. Low contrast D. High brightness
C. Low contrast
Which of the following devices is the most accurate monitor used to measure occupational radiation exposure? a. film badge b. thermoluminescent dosimeter c. optically stimulated luminescent dosimeter d. Geiger counter
C. Optically stimulated luminescent dosimeter
Which of the following would normally not be used to administer contrast with a power injector? a. power PICC line b. power port-a-cath c. perma-cath d. A and B are correct.
C. Perma-cath
When using a gonadal shield for a CT exam, the shield should be: a. placed anteriorly (on top of the pelvis). b. placed posteriorly (underneath the pelvis). c. wrapped 360 degrees around the patient. d. It is not necessary to use gonadal shielding for CT scans.
C. Wrapped 360 degrees around the patient
Which of the following International System of Units (SI) measurements is associated with monitoring radiology staff? a. coulomb/ kilogram (C/ kg) b. becquerel (Bq) c. gray (Gy) d. sievert (Sv)
D. sievert (Sv)
Partial volume averaging occurs when: 1. similar tissue types share the same voxel. 2. cardiac studies are performed. 3. metal objects are present within the patient or the patient's clothing. 4. detector elements fail.
1. similar tissue types share the same voxel.
Which of the following is not a postprocessing technique? A. Longitudinal interpolation B. Image smoothing C. Volume rendering D. Maximum intensity projection (MIP)
A. Longitudinal interpolation
Radiopaque nonionic contrast agents are considered safe for pregnant patients. a. true b. false
A. True
A digital to analog converter is needed to: A. display data on a lCD monitor B. encode transmitted radiation into binary data C. change the remnant beam to an electric signal D. transform the electric signal to light
A. display data in a LCD monitor
When a spiral helical CT scanner takes a scout image, the X-ray tube: A. is stationary B. can take a frontal and lateral projection at the same time C. rotates around the patient
A. is stationary
Compared with volume acquisition, axial acquisition results in: A. lower partial volume averaging B. better high-contrast resolution C. increased noise D. thinner slices
A. lower partial volume averaging
As the display field of view (DFOV) decreases: I. noise increases II. spatial resolution increases III. spatial resolution decreases A. II&III B. I&II C. I&III D. I, II, III
B. I&II
Backprojection is associated with: a. helical/spiral scanning. b. artifacts. c. increased image sharpness. d. pitch.
B. artifacts
What is the effect of increased image noise? A. increased contrast resolution B. decreased contrast resolution C. improved image quality D. A and C are correct
B. decreased contrast resolution
As postpatient collimation decreases, slice thickness: a) decreases. b) increases. c) remains the same.
B. decreases
Which generation of CT scanners is associated with the term "EBCT" and the use of an electron beam gun? A. seventh B. fifth C. sixth D. fourth
B. fifth
The term "misregistration" refers to: A. back projection reconstruction B. incorrect image reconstruction C. convolution D. noise
B. incorrect image reconstruction
Which of the following quality control (QC) tests should be performed daily? I. CT number calibration II. CT couch indexing III. Standard deviation of the CT number in water A. I, II, & III B. II & III C. I & III D. I & II
C. I & III
Which of the following are functions of the patient table? I. contributes to patient safety II. enhances subject contrast III. transport patient through the gantry A. I&II B. I, II, and III C. I&III D. II&III
C. I&III
For CT scanning, as mAs increases, patient dose _____ and image noise ____. a. decreases; decreases b. increases; increases c. increases; decreases d. decreases; increases
C. Increases; decreases
Which of the following tests determines the ability of the patient table to return to its original position after the scan? A. slice width B. CT table indexing C. localization device accuracy D. CT table backlash
D. CT table backlash
Which of the following medications most likelywould be used to treat urticaria (hives)? a. metformin b. dopamine c. naloxone d. diphenhydramine
D. Diphenhydramine
Which of the following is nota common contrast injection reaction? a. pain at the injection site b. metallic taste c. flushed feeling in the pelvis d. dyspnea
D. Dyspnea
What is the standard orientation a patient is scanned?
Head first, Supine.
Cone-beam artifacts only appear in _____ scanners. a. first generation b. second generation c. third generation d. multislice
d. multislice
CompCompared with traditional single-slice axial scanners, helical/spiral scanners acquire images at _____ rate. 1. Faster 2. Same 3. Slower 4. Light Speed
1. Faster
Which of the following is the most effective type of CT detector? 1. Scintillation 2. Xenon gas 3. Linear array 4. Photodiode
1. Scintillation
The first commercial CT scanner was available during the: 1. The 1970s 2. The 1980s 3. The 1960s 4. The 1990s
1. The 1970s
CT is commonly referred to as all of the following names, EXCEPT: 1. CAT-Scan 2. Digital Subtraction Angiography 3. Computed Tomography 4. Computerized Axial Tomography
2. Digital Subtraction Angiography
A 16-slice helical/spiral scanner produces _____ images from a single slice of scan data. 1. 12 2. 16 3. 8 4. 120
2. 16
Which of the following factors decreases contrast resolution? 1. Smaller Field SIze 2. Smaller Matrix Size 3. Smaller Pixel Size 4. Higher mAs
3. Smaller Pixel Size
The scan field of view (SFOV) is determined by the: 1. Pitch 2. Prepatient collimators. 3. Postpatient collimators. 4. CT technologist before the scan begins
4. CT technologist before the scan begins
Which of the following tests determine the uniformity of CT numbers throughout the image? 1. High Contrast Resolution 2. Low Contrast Resolution 3. Standard Deviation of Ct numbers in H20 4. CT Number Flatness
4. CT number flatness
A first generation scanner: 1. Used a curved array of detectors 2. Produced an imagine less than 5 seconds 3. Used multiple detectors 4. Used a pencil beam of x-rays
4. Used a pencil beam of x-rays
Tube arching occurs: 1. outside the x-ray tube 2. Inside the x-ray tube 3. because of fluctuations in the line voltage A. 1&2 B. 1&3 C. 3&2 D. 1, 2, &3
A. 1&2
Which of the following would most likely be associated with a CT scan of the lung? A. WW 1500; WL -400 B. WW 80; WL -400 C. WW 1600; WL -400 D. WW 80; WL 40
A. WW 1500; WL -400
When manipulating an image using the zoom tool, the resolution: A. decreases B. stays the same C. increases
A. decreases
Which of the following factors decreases contrast resolution? A. smaller pixel size B. higher mAs C. smaller matrix size D. smaller field of view
A. smaller pixel size
The half-scan algorithm technique is used to improve: a. temporal resolution. b. uniformity. c. linearity. d. spatial resolution.
A. temporal resolution
Radiopaque nonionic contrast agents are considered safe for pregnant patients a. true b. false
A. true
Spactial resolution can be improved by using: 1. thin slice thicknesses. 2. a matrix with large pixel sizes. 3. small detector sizes. A. 1 and 3 B. 1 and 4 C. 1 and 2 D. 2 and 3
A.1 and 3
Spiral-helical CT scanning is based on: 1. Sequential data acquisition. 2. Slip-ring technology. 3. Volume data acquisition. 4. B and C are correct.
B and C are correct.
Overlap occurs when the pitch is less than: A. overlap is not related to pitch B. 1.0 C. .5 D. 1.5
B. 1.0
50 millisievert (mSv) is equal toa. 15 rem.b. 5 rem.c. 50 Gy.d. 100 Gy.
B. 5 rem
Which of the following medications may be used to prevent nephrotoxicity? a. metformin b. acetylcysteine c. glucophage d. diphenhydramine
B. Acetylcysteine
Which of the following x-ray beam geometries is used by modern, multi detector CT scanners? A. pinpoint beam B. Cone beam C. Pencil beam D. Fan beam
B. Cone beam
Compared with conventional (axial) CT scanning, spiral-helical CT has: A. Longer interscan delays B. Faster imaging times C. increased misregistration artifacts D. B and C are correct
B. Faster imaging times
In multislice CT scanners, detector systems with equal size detector elements are called ___ arrays A. symmetric B. linear C. curved D. B and C are correct
B. symmetric
Patients taking metformin should stop taking the medication ___hours after having IV contrast media injection. a. 12 b. 24 c. 48 d. 72
C. 48
A pitch of ___ results in the highest patient dose to the patient a. 1 b. 2 c. less than 1 d. Pitch does not affect patient dose.
C. A pitch less than 1
Which of the following is considered a secondary protective radiation barrier? a. lead apron b. thyroid shield c. CT control room walls d. protective glasses
C. CT control room walls
Which of the following tests determines the uniformity of CT numbers throughout the image? A. standard deviation of CT numbers in water B. high-contrast resolution C. CT number flatness D. low-contrast resolution
C. CT number flatness
As the display field of view increases, the resulting radiation dose to the patient: a. decreases b. increases c. is not affected.
C. Is not affected
A CT gantry includes all of the following components except" A. detectors B. bow tie filters C. central processing unit D. collimators
C. central processing unit
As pitch increases, patient dose: A. is unaffected B. increases C. decreases
C. decreases
Which of the following techniques reduces edges gradient artifacts? A. using detectors with large space apparatus B. decreasing data sampling rates C. scanning with thinner slices D. scanning with thicker slices
C. scanning with thinner slices
Which generation CT scanners was the first to use a curved array of rotating detectors? A. second B. fourth C. third D. fifth
C. third
Ring artifacts only appear in _____ scanners. a. first generation b. second generation c. third generation d. multislice
C. third generation
Auto milliamperage is generally used during the acquisition of: A. a region of interest B. interactive data C. topogram D. a standard convolution algorithm
C. topogram
CT scanner x-ray tubes incorporate rotating anodes composed of: a) tungsten, copper and molybdenum. b) molybdenum, tungsten and rhodium c) tungsten, molybdenum and rhenium d) rhenium, tungsten and rhodium.
C. tungsten, molybdenum, and rhenium
Cupping artifacts are most closely related to which image quality? a. linearity b. contrast resolution c. uniformity d. temporal resolution
C. uniformity
What is the window level if the CT/ Hounsfield range is 200 to 1000? A. 400 B. 500 C. 800 D. 600
D. 600
A CT scanner with 16 detector rows, each scanning 4 widths, is called a ____-slice scanner a. 4 b. 8 c. 16 d. 64
D. 64
Gating is a technique that can effectively reduce patient dose by as much as ____%a. 100b. 90c. 80d. 70
D. 70
Spiral-helical CT scanning is based on: A. sequential data acquisition B. slip-ring technology C. volume data acquisition D. B and C are correct
D. B and C are correct
Tube arching occurs: I. inside the x-ray tube II. outride the x-ray tube III. because of fluctuations in line voltage A. I, II, III B. I&III C. II&III D. I&II
D. I&II
Spatial resolution can be increased by using: I. larger-size detectors II. a smaller pixel size III. thinner slice thickness A. I & II B. I & III C. I, II, & III D. II & III
D. II & III
Which of the following medications reverses the effects of narcotics?a. atropine sulfateb. diphenhydraminec. dopamined. naloxone
D. Naloxene
Modern multislice CT scanners use _____ geometry. a. fan-beam b. parallel-beam c. pencil-thin beam d. cone-beam
D. cone-beam
In multi-slice CT, as the pitch decreases, the z-gap ___ and image quality_____ A. decreases; is unaffected B. increases; increases C. increases; decreases D. decreases; increases
D. decreases; increases
First-generation scanners were only capable of imaging the: A. neck B. chest, abdomen and pelvis C. extremeties D. head/brain
D. head/brain
In helical/ spiral scanning, overlapping results in __ patient dose and ___ spatial resolution. A. increased; decreased B. decreased; increased C. decreased; decreased D. increased; increased
D. increased; increased
Which of the following is not an example of a kernel? A. standard convolution algorithm B. smoothing filter C. edge enhancement filter D. interactive algorithm
D. interactive algorithm
All power to the gantry of a spiral-helical CT scanner is conveyed via: a. high-tension cables. b. rotating wire brushes. c. photon flux. d. slip rings.
D. slip rings
All spiral-helical scanners incorporate copper brushes as a component of the slip-ring design. True False
False
When scanning a patient's thorax why do we move their arms up and out of the scan if possible? Try to elaborate.
Helps reduce scatter and also reduces dose to arms.
Which of the following detector types produce high quality images? Scintillation Gas Linear
Scintillation
Absorption efficiency refers to how efficiently x-ray photons are captured by the detectors. True False
True
The bowels
What is the orange?
The heart
What structure is circled in Red?
Ghosting refers to _____ artifacts. a. motion b. cupping c. ring d. static
a. Motion
Image noise can be reduced by: a. inecreasing mAs. b. increasing slice thickness. c. decreasing pixel size. d. A and C are correct.
a. increasing mAs.
Which of the following medications most likely would be used to treat chest pain by angina? a. nitroglycerin b. soluMedrol c. dopamine d. naloxone
a. nitroglycerin
The CT dose index (CTDI) is most accurate when applied to: a. single-slice scanners. b. multislice scanners. c. helical/spiral scanners.
a. single-slice scanners.
The window width (WW) determines the: a) image density. b) image contrast. c) voxel depth. d) voxel width.
b) image contrast.
The typical modern CT scanner generator converts: a) low-voltage AC to high-voltage DC. b) low-voltage DC to high-voltage DC. c) high-voltage DC to low-voltage DC. d) low-voltage DC to high-voltage AC.
b) low-voltage DC to high-voltage DC.
Modern CT scanners are able to differentiate tissue with density differences of less than _____ %. a. 1.0 b. 0.5 c. 0.1 d. 0.15
b. 0.5
Beam-shaping filters are designed to: a. remove higher-energy photons from the beam. b. change the spatial distribution of the beam. c. decrease subject contrast. d. restrict the path of photons coming from the x-ray tube.
b. change the spatial distribution of the beam
How can partial volume averaging be reduced? a. scanning with thicker slices b. scanning with thinner slices c. using a half-scan algorithm d. B and C are correct.
b. scanning with thinner slices
CT scanner x-ray tube voltages range from ______ to _____ kilovolts (kV). a. 60; 100 b. 80; 120 c. 80; 140 d. 100; 160
c. 80; 140
Window level (WL) refers to: 1. the midpoint in a range of CT numbers. 2. image contrast. 3. image brightness. a) 1 and 2 b) 1 and 3 c) 2 and 3 d) 1, 2 and 3
d) 1, 2 and 3
