Test one Advanced Imaging Modalities
The window width is 400 and ranges from -50 to +350. Therefore, the window level is 100. TRUE OR FLASE
FALSE
As pitch increases, patient dose: is unaffected decreases increases
decreases
When using a gonadal shield for a CT exam, the shield should be: 1) placed anteriorly on top of the pelvis 2) it is not necessary to use gonadal shielding for CT scans 3) wrapped 360 degrees around the patient 4) placed posteriorly underneath the pelvis
wrapped 360 degrees around the patient
What is the position of the x-ray tube in relation to the gantry when obtaining a lateral scout scan for a brain.
x-ray tube is horizontal or in the 9 o' clock position
Which of the following CT numbers represents water? + 1000 0 +500 -1000
0
One tesla is equal to ________ gauss. Answers: 100 1,000 10,000 100,000
10,000
The typical kilovolt peak (kVp) range used for CT scans is: 90-100 100-120 100-140 120-160
100-140
The ________ is a perimeter around the scanner defining where the static field is potentially hazardous. Answers: 1.5 T circle 5-gauss line 3.0 T line 3-gauss circle
5-gauss line
Which of the following is considered a secondary protective radiation barrier? thyroid shield protective glasses lead apron CT control room walls
CT control room walls
As slice thickness increases, the patient's dose increases? True or False
False
A standard algorithm program was used to reconstruct the brain from the top of the head to the base of the skull. In order to have images that show bone contrast, the technologist must readjust the: 1) raw data 2) the window level 3) the window width a. 1 only b. 1&2 only c. 2&3 only d. 1,2 & 3
c. 2&3 only
In multi-slice CT, as the pitch increases, the z gap _____ and image quality _______. increases, is unaffected increases, increases decreases, increases increases, decreases
decreases, increases
The CT dose index (CTDI) is most accurate when applied to: multislice scanners single-slice scanners helical/spiral scanners
single-slice scanners
All power to the gantry of a spiral-helical CT scanner is conveyed via: rotating wire brushes slip rings high tension cables photon flux
slip rings
In multislice CT scanners, detector systems with equal-size detector elements are called _____ arrays. curved symmetric adaptive linear
symmetric
The mathematical unit that describes shades of gray on a CT image is called: the Hounsfield unit the window width the window level a voxel unit
the Hounsfield unit
When protons spin, they: 1.create a small magnetic field. 2.create a small magnetic moment. 3.lose their electrical charge. Answers: 1 and 2 1 and 3 2 and 3 1, 2, and 3
1 and 2 1.create a small magnetic field. 2.create a small magnetic moment.
The process of producing voltage using magnetic fields is called: 1.electromagnetic induction. 2.the Larmor equation. 3.the Faraday law. Answers: 1 and 2 1 and 3 2 and 3 1, 2, and 3
1 and 3 electromagnetic induction. the Faraday law.
The direction parallel to the B0 is the: 1.longitudinal direction. 2.transverse plane. 3.Z axis. Answers: 1 and 2 1 and 3 2 and 3 1, 2, and 3
1 and 3 longitudinal direction. .Z axis.
Window level (WL) refers to: 1) the midpoint in a range of CT numbers 2) image contrast 3) image brightness
1&3 1) the midpoint in a range of CT numbers 3) image brightness
Which of the following most closely approximates the actual radiation dose to a specific patient for a specific exam? 1) dose length product (DLP) 2) multiple scan average dose (MSAD) 3) none of these
1) dose length product (DLP)
Fringe magnetic fields can interact with: 1.CT scanners. 2.pacemakers. 3.nuclear medicine scanners. 1 and 2 1 and 3 2 and 3 1, 2, and 3
1, 2, and 3
A patient in the scanner during an uncontrolled quench should be removed immediately to avoid possible: 1.frostbite. 2.ruptured tympanic membrane. 3.asphyxiation. Answers: 1 and 2 1 and 3 2 and 3 1, 2, and 3
1, 2, and 3 1.frostbite. 2.ruptured tympanic membrane. 3.asphyxiation.
Sudden increases in body temperature from RF energy can cause problems for patients with: 1.high blood pressure. 2.certain cardiac conditions. 3.diabetes Answers: 1 and 2 1 and 3 2 and 3 1, 2, and 3
1, 2, and 3 1.high blood pressure. 2.certain cardiac conditions. 3.diabetes
Which of the following MR scanner types work well for large claustrophobic patients? 1.short bore 2.open bore 3.high field Answers: 1 and 2 1 and 3 2 and 3 1, 2, and 3
1, 2, and 3 1.short bore 2.open bore 3.high field
Preventing potentially serious injury or death from strong magnetic field strengths requires: 1.a knowledgeable and concerned MR technologist. 2.controlled access to the magnetic field. 3.a detailed medical history of anyone entering the room. Answers: 1 and 2 1 and 3 2 and 3 1, 2, and 3
1, 2, and 3 a knowledgeable and concerned MR technologist. controlled access to the magnetic field. a detailed medical history of anyone entering the room.
Under normal conditions, for which of the following magnet types is the magnetic field always on? 1.resistive 2.permanent 3.superconducting Answers: 1 and 2 1 and 3 2 and 3 1, 2, and 3
2 and 3 permanent superconducting
Second generation scanning employed: 1) a pencil beam/a single detector 2) a fan beam/ multidectectors 3) more indexing (compared with first generation scanners) 1 only 1&3 2&3 2 only
2 only a fan beam/ multidectectors
For CT scanning, as mAs increases, patient dose_____ and image noise _________. 1) increases, increases 2) decreases, increases 3) increases, decreases 4) decreases, decreases
3) increases, decreases
50 millisievert (mSv) is equal to: 50 Gy 5 rem 100 Gy 15 rem
5 rem
The National Council on Radiation Protection and Measurements (NCRP) recommends that the annual occupational dose for imaging professionals not exceed: 1 mSv 5 Sv 5 mSv 50 mSv
50 mSv
Which generation of CT scanners is associated with the term "EBCT" and the use of an electron beam gun? 4th 7th 5th 6th
5th
Gating is a technique that can effectively reduce patient dose by as much as _____% 80 70 90 100
70
According to FDA guidelines, adults can be scanned using a static magnetic field strength of up to ______ T. Answers: 3.0 1.5 11.0 8.0
8.0
CT scanner x-ray tube voltages range from _____ to_____ kilovolts (kV) 80, 120 80, 140 60, 100 100, 160
80, 140
The static magnetic field is abbreviated as ________. Answers: Bg B0 M B1
B0
Which of the following statements is true regarding magnetism? 1.Diamagnetic substances are repelled by the magnetic field. 2.Tungsten, platinum and gadolinium are examples of 3.diamagnetic substances. 4.Most substances have no magnetism. 5.Diamagnetic substances have unpaired orbital electrons.
Diamagnetic substances are repelled by the magnetic field.
A seamless shield surrounding the MR room is called a(n)________. birdcage fringe shield active shield Faraday cage
Faraday cage
Which of these is not a characteristic of a superconducting magnet? Answers: Electrical current flows without resistance. Cost is between $1 million and $3 million. Field strengths are limited to below 2T. It uses liquid cryogens to control resistance.
Field strengths are limited to below 2T.
________ are used to cool the wires of superconducting magnets. Answers: Synthetic chemicals Special electrical systems Solid cryogens Liquid cryogens
Liquid cryogens
If a patient has an emergency while in the scanning room, how should the MR technologist physically address administering lifesaving procedures? Answers: Transfer the patient to the emergency department. Leave the patient where he or she is to do no further harm. Remove the patient from the scanner, but keep the patient in the room and begin CPR. Remove the patient from the MR scanning room to a safe area on an MR-conditional stretcher and then begin lifesaving procedures.
Remove the patient from the MR scanning room to a safe area on an MR-conditional stretcher and then begin lifesaving procedures.
The size of the field of view (FOV) represents the length of the diameter created when the x-ray tube scans around the patient. TRUE OR FALSE
TRUE
T1 sagittal
The attached image represents: Answers: T1 sagittal DWI FLAIR axial T2 sagittal
an MRA of the carotid arteries
This image should be described as a lower extremity venogram an MRA of the carotid arteries an MRA of the COW none of the above
a T2 coronal brain
This image should be described as: Answers: a T2 axial brain a T1 axial brain a T1 coronal brain a T2 coronal brain
a T1 coronal brain
This image should be described as: Answers: a T1 axial brain a T2 sagittal brain a T2 coronal brain a T1 coronal brain
An image is said to have good spatial resolution if the boundaries of an object are distinct and have sharp borders. True or False
True
As windows width increases the contrast decreases True or False
True
Linear attenuation coefficient values relate directly to density depicted as a CT number, where the CT value zero represents water density. True or False
True
Which of the following would most likely be associated with a CT scan of the lung? WW 80; WL -400 WW 1500; WL 400 WW 80; WL 40 WW 1600; WL 300
WW 1500; WL 400
Which of the zones established by the ACR for safety, houses the actual magnet? Answers: Zone I Zone II Zone III Zone IV
Zone IV
The function of a bow-tie filter is/are to: 1) decreases the beam energy at the periphery of the patient 2) shape the beam to be more polychromatic 3) minimize beam hardening artifacts a. 1 only b. 1&2 only c. 2&3 only d. 1,2&3
a. 1 only decrease the beam energy at the periphery of the patient
An image that appears grainy is said to have low ______. Answers: a. SNR b. Scan time c. Spatial resolution d. NEX
a. SNR
The x-ray photons transmitted through the patient are received by a/an: a. array detectors b. image receptor c. image intensifier d. selenium plate
a. array detectors
As a technologist, if you want to decrease the original pixel size by half, what scanning parameter must be changed? a. field of view (FOV) b. slice thickness c. decrease the number of pixels d. increase the number of pixels
a. field of view (FOV)
Which complication is most likely during an MRI of a patient who has had a pacemaker removed but still has the leads in place? Answers: a. induced current in the leads b. displacement of the leads due to magnetic force c. hemorrhage from torquing (twisting) of the lead d. non-functioning pacemaker
a. induced current in the leads
Family members or non-MRI personnel accompanying a patient into the exam room: Answers: a. should undergo the same screening process used on the patient b. can safely enter the scan room to check on the patient but cannot stay during the scan c. do not need to be screened since they will not be in the scanner d. must wear magnetic shielding during the scan
a. should undergo the same screening process used on the patient
In CT imaging, the Z- axis refers to the _____ plane. sagittal axial coronal oblique
axial
Volume acquisition scanners are based on: 1. slice-by-slice data acquisition 2.slip-ring technology 3. continuous rotation of the x-ray tube a. 1,2&3 b. 2&3 c.1&2 d. 1&3
b. 2&3 2. slip-ring technology 3. continuous rotation of the x-ray tube
The time between excitation pulses is known as the: a. TE b. TR c. TI d. wait time
b. TR
A patient with ferromagnetic intracranial aneurysm clips is at risk of Answers: a. thermal injuries b. intracranial hemorrhage from torquing (twisting) of the clip c. hearing loss d. all of these e. pulling of the clip out of the cranium
b. intracranial hemorrhage from torquing (twisting) of the clip
A T1 weighted image is produced using a _____ TR and a _____ TE and produces an image with _______ fat. Answers: a. long; short; bright b. long; long; bright c. short; short; bright d. long; long; dark e. short; short; dark
c. short; short; bright
Patients with large or especially dark tattoos are at risk of Answers: a. torquing injuries b. nothing c. thermal injuries d. current induction in the skin
c. thermal injuries
A CT gantry includes all of the following components except: detectors collimators bow tie filters central processing unit
central processing unit
Beam-shaping filters are designed to: remove higher-energy photons from the beam restrict the path of photons coming from the x-ray tube change the spatial resolution of the beam decrease subject contrast
change the spatial resolution of the beam
Which of these is not a contraindication for entering the MR suite? claustrophobia cardiac pacemakers infusion pumps aneurysm clips
claustrophobia
An image acquisition that divides the body into front and back halves is called a(n) ________ projection. Answers: coronal sagittal transverse axial
coronal
Which of the following statements are true regarding MR imaging of a pregnant patient? Answers: a. MRI procedures are considered completely safe since they do not use ionizing radiation b. MRI should never be performed on a pregnant patient because the harmful effects are not fully understood c. gadolinium based contrast have been proven have no effect on the fetus d. Each situation should be evaluated based on the benefit vs risk of the procedure
d. Each situation should be evaluated based on the benefit vs risk of the procedure
In preparation for an MRI procedure, patients should be encouraged to: Answers: a. wear their own clothing so they feel at home during the study b. wear a wrist watch to monitor the length of the scan time c. keep their hearing aids in so they can hear and follow the technologists instructions d. none of the above
d. none of the above
The people who should be educated about the effects of the static magnetic field, especially in high field superconducting magnets, are: Answers: a. nursing staff and the code team b. housekeeping and fire department c. anesthesiologists and respiratory therapists d. a and c only e. all of the above
e. all of the above
First generation scanners were only capable of imaging the: head/brain and extremities chest, abdomen/pelvis extremities head/brain
head/brain
Generators are often times located within the gantry. These types of generators are typically: high frequency medium frequency full wave/ 3 phase multiwave/ 2 phase
high frequency
A superconducting magnetic field generally runs: 1. horizontally along the long axis of the patient's body. 2. in a straight line from the magnet bore to the edge of the room. 3.horizontally from bore to wall. 4.vertically from ceiling to floor.
horizontally along the long axis of the patient's body.
In multidetector CT scanning, which of the following determines slice thickness? image reconstruction parameters postpatient collimators detector type prepatient collimators
image reconstruction parameters
When a ferromagnetic object gets closer to the magnet, the magnetic force pulling the object: Answers: stops suddenly. decreases slightly. increases exponentially. increases slightly
increases exponentially.
When a spiral-helical CT scanner takes a scout image, the x-ray tube: is stationary rotates around the patient can take a frontal and lateral projection at the same time
is stationary
Compared to barium used for regular fluoroscopy procedures, the barium used for CT procedures is : more dense of the same density less dense
less dense
A pitch of ________ results in the highest dose to the patient. less than 1 pitch does not affect patient dose 1 2
less than 1
A permanent magnet usually is constructed of magnetized ceramic bricks or a magnetized alloy made of aluminum, ________ and ________. Answers: nickel; cobalt steel; nickel tungsten; nickel cobalt; tungsten
nickel; cobalt
In a well-known accident that occurred in July 2001, a(n) ________ flew through the scanner room, striking and killing a 6-year-old boy. Answers: oxygen tank emergency crash cart pair of forceps wheelchair
oxygen tank
First generation CT scanners used _____ beam scanning. fan cone pencil pinpoint
pencil
Which of the following describes a characteristic of a first-generation CT scanner? a. image intensifier b. multiple beam sources & multi-row detectors c. pencil x-ray beam and 1 detector d. multiple detectors and fan beam
pencil x-ray beam and 1 detector
Which of the following would normally not be used to administer contrast with a power injector? perma-cath power PICC line power port-a-cath any of these may be safely used
perma-cath
When image data is acquired by a CT scanner, it goes through a process known as: quantization photon flux convolution digitization
quantization
MR-approved ECG leads are made of ________ to prevent thermal burns. Answers: aluminum nickel titanium silver
silver