Term
Tungsten is used as the target material on the tube's anode because it has a ____ atomic number and a ____ melting point.
a. low,high
b. high, low
c. low, low
d. high, high |
|
Definition
|
|
Term
________ scanner design was teh first to acquire four slices in a single rotation.
a. Second-generation
b. Third-generation
c. Multi-row detector
d. Continuous rotation |
|
Definition
Answer:
c. Multi-row detector |
|
|
Term
The enormous heat that builds up in the CT tube is caused by the:
a. intensity of the x-rays emitted from the tube
b. electron beam between the cathode and the anode in the tube
c. x-ray filter in the tube which absorbs the lower energy photons before they can enter the patient
d. collision of the electron beam with the tungsten target on the tube anode |
|
Definition
| d. collision of the electron beam with the tungsten target on the tube anode |
|
|
Term
The number of electrons that flow from the cathode to the anode in the tube is controlled by the:
a. anode target
b. collimation
c. mA
d. kV |
|
Definition
|
|
Term
The slip ring on continous 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
a. 1 only
b. 2 only
c. 3 only
d. 1,2,&3 |
|
Definition
|
|
Term
Which of the followind is NOT a part of the CT tube?
a. tungsten target
b. collimator
c. rotating anode
d. filament |
|
Definition
|
|
Term
Which of the following are NOT commonly used on today's commecially available CT scanners?
1. xenon detectors
2. fourth-generation technology
3. continuous rotation technology
a. 1 only
b. 1 & 2
c. 2 & 3
d. 1, 2, &3 |
|
Definition
|
|
Term
Which system component converts the projection attenuation data into the proper digital form for the array processor?
a. detector
b. photodiode
c. analog-to-digital converter
d. host computer |
|
Definition
Answer:
c. analog-to-digital converter |
|
|
Term
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
a. 1 only
b. 2 only
c. 3 only
d. 1,2,&3 |
|
Definition
|
|
Term
Which of the following is TRUE regardin solid state detectors?
1. x-ray photons cause the detectors to generate a flash of light
2. they are the detector type used on most CT scanners today
3. they can be used in both third-generation and fourth-generation CT systems
a. 1 only
b. 2 only
c. 3 only
d. 1,2, &3 |
|
Definition
|
|
Term
CT is commonly referred to as all of the following names EXCEPT:
a. computerized axial tomography
b. digital subtraction angiography
c. CAT-scan
d. computed tomography |
|
Definition
Answer:
b. digital subtraction angiography |
|
|
Term
What control does the operator have over the x-rays in a CT exam?
a. the temperature and color of the x-rays can be tuned
b. the energy level and the quantity of x-rays can be selected
c. the volume and tone of the x-rays can be dialed
d. the phase and frequency of the x-rays can be adjusted |
|
Definition
Answer:
b. the energy loevel and the quantity of x-rays can be selected |
|
|
Term
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 filament
2. kV contols the energy level of the x-ray photons and mA controls the number of x-ray photons emitted from the tube
3. although the kV and the mA affect the operation of the CT x-ray tube, the two parameters have no bearing on the image quality
a. 1 only
b. 2 only
c. 1 & 2
d. 2 & 3 |
|
Definition
|
|
Term
Which of the following does NOT affect the quantity of 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
a. 1 only
b. 2 only
c. 3 only
d. 1,2, &3 |
|
Definition
|
|
Term
____________made helical imaging possible.
a. Multi-row detector scanners
b. The introduction of second-generation technology
c. The introduction of fourth-generation technology
d. Continuous rotation scanners |
|
Definition
Answer:
c. continuous rotation scanners |
|
|
Term
Which of the following statements is FALSE regarding the collection of CT data?
a. long scan times are more desirable because they average out motion artifacts
b. the reconstruction process used to create the image occurs in the array processor
c. to collect the complete set of CT data, xrays must be passed through the body at many different angles
d. the detectors measure x-rays which completely penetrate the patient |
|
Definition
Answer:
a. long scan times are more desirable because they average out motion artifacts |
|
|
Term
Which of the following is a component NOT normally located in the gantry of a modern CT system?
a. pre-patient collimators
b. solid-state detectors
c. array processor
d. x-ray tube |
|
Definition
Answer:
c. array processor |
|
|
Term
X-rays are used in CT because:
a. they are easily produced by the high frequency generator
b. they are less harmful than the heating effects of microwave radiation
c. they penetrate the body according to specific attenuation characteristics of each tissue
d. the FDA imposes no limit on the dose to the patient |
|
Definition
Answer:
c. they penetrate the body according to specific attenuation characteristics of each tissue |
|
|
Term
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 electron and an electron in an inner shell of the target 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
a. 1 only
b. 2 only
c 3 only
d. 1,2, &3 |
|
Definition
|
|
Term
The mA determines the:
a. quantity of x-ray photons
b. coefficient of attenuation
c. slice thickness
d. energy level of the x-ray photons |
|
Definition
Answer:
a. quantity of x-ray photons |
|
|
Term
Increased_____will increase the likelihood that a given x-ray will penetrate a material.
1. kV
2. mA
3. exposure time
a. 1 ony
b. 2 only
c. 3 only
d. 1,2,&3 |
|
Definition
|
|
Term
Collimation:
a. is accomplished by electrically blocking x-rays
b. affects the scan time
c. limits the low energy x-ray photons and passes the high energy photons
d. is accomplished by physically blocking x-rays |
|
Definition
Answer:
d. is accomplished by physically blocking x-rays |
|
|
Term
Scatter radiation is caused by:
a. miscalibrated detector
b. x-rays generated spontaneously in the ambient atmosphere
c. deflections from the original trajectory of an x-ray photon through the patient
d. improper patient positionins |
|
Definition
Answer:
c. deflections from the original trajectory of an x-ray photon through the patient |
|
|
Term
Which technology do multi-row detector scanners employ?
a. second-generation
b. third-generation
c. fourth-generation
d. first-generation |
|
Definition
Answer:
b. third-generation |
|
|
Term
Which of the following is NOT a function of a PACS system?
a. reconstruction of the image from the raw data
b. long term data storage
c. digital distribution of images
d. image display for the radiologists |
|
Definition
Answer:
a. reconstruction of the image from the raw data |
|
|
Term
Which of the following is TRUE regarding multi-row detector CT scanners?
1. the size of the detector arrays along the z-direction may be different
2. the attenuation information from adjacent detector arrays may be added together to generate thicker slices
3. all of the detector arrays may or may not be used
a. 1 only
b. 2 only
c. 3 only
d. 1,2, &3 |
|
Definition
|
|
Term
Which of the following is FALSE regarding CT systems?
1. they are limited to non-oblique transverse scanning
2. they cannot generate a straight coronal or sagittal image
3. they have no moving parts
a. 1 only
b. 2 only
c. 3 only
d. 1,2, &3 |
|
Definition
|
|
Term
Most of the commands from the technologist are received by the:
a. array processor
b. operator's console
c. host computer
d. amplifier |
|
Definition
Answer:
b. operator's console |
|
|
Term
The operator's console may include:
1. monitor
2. keyboard
3. graphic input device
a. 1 only
b. 2 only
c. 3 only
d. 1,2, &3 |
|
Definition
|
|
Term
Which of the following CT scanner designs does NOT use an x-ray tube?
a. firt-generation CT
b. PET/CT
c. electron beam CT
d. MDCT |
|
Definition
Answer:
c. electon beam CT |
|
|
Term
Tube interscan delay time refers to:
a. the time betweeen the end of one scan and the start of the next scan during which the tube will coll
b. a quality assurance test performed daily by the technologist
c. the time required for the tube to make a complete 360 degree revolution about the gantry
d. the length of time required for the production of photons to begin after applying the voltage to the tube |
|
Definition
Answer:
a. the time between the end of one scan and the start of the next scan during which the tube will cool |
|
|
Term
On a single-row detector scanner, collimation:
1. controls teh slice thickness
2. minimizes the x-ray dose to the patient
3. reduces the detection of scatter radiation
a. 1 only
b. 2 only
c. 3 only
d. 1,2, &3 |
|
Definition
|
|
Term
The main purpose of the detector is to:
a. provide additional collimation in order to reduce scatter
b. limit the x-ray dose to the patient
c. capture x-ray photons and convert them to a measurable signal
d. amplify the measured signal |
|
Definition
Answer:
c. capture x-ray photons and convert them to a measurable signal |
|
|
Term
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
a. 1 only
b. 2 only
c. 3 only
d. 1,2, &3 |
|
Definition
|
|
Term
The patient table:
a. may move continuosly during the scan
b. can never be positioned automatically by software due to safety precautions
c. remains stationary throughout the patient exam once it in initially positioned
d. only moves after each slice is completed |
|
Definition
Answer:
a. may move continuously during the scan |
|
|
Term
Which of the following statements is FALSE regarding occurrences afte an x-ray photon penetrates the detector aperature?
1. the photon can pass through the detector unmeausred
2. the photon is converted completely into a n electron
3. the measured signal is enhanced by an amplifier
a. 1 only
b. 2 only
c. 3 only
d. 1,2, and 3 |
|
Definition
|
|
Term
CT images can be directly scanned in planes other than transverse by:
1. orienting the patient's body part so that it is not perpendicular to the x-ray beam
2. tilting the gantry
3. changing the angle that the x-ray beam leaves the tube
a. 1 only
b. 1 and 2
c. 2 and 3
d. 1,2 and 3 |
|
Definition
|
|
Term
The CT x-ray tube rotates around the patient to:
1. keep the tube cool
2. generate projection views at different angles
3. minimize the x-ray dose administered to the patient
1. 1 only
2. 2 only
3. 3 only
4. 1,2, &3 |
|
Definition
|
|
Term
The cathode filament:
a. helps determine the size of the focal spot
b. lights up the tube so it can be serviced by an engineer
c. releases the x-ray photons
d. focuses electrons onto the anode target |
|
Definition
Answer:
d. focuses electrons onto the anode target |
|
|
Term
The goals of history-taking include all of the following EXCEPT:
a. assessing the patient's risk factors for IV contrast reactions
b. verifying the accuracy of the information in the patient's chard
c. verifying that the patient has signed a living will and durable power of attorney
d. establishing an initial rapport with the patient |
|
Definition
Answer:
c. verifying that the patient has signed a living will and durable power of attorney |
|
|
Term
Patients who have had a prior allergic reaction to a contrast agent should be asked all of the following EXCEPT:
a. how severe were the symptoms?
b. what was the nature of the reaction?
c. what medications were you taking at the time?
d. how were the symptoms treated? |
|
Definition
Answer:
c. what medications were you taking at the time? |
|
|
Term
The localizer scan for a chest CT scan should encompass the ______ superiorly to the _________inferiorly.
a. thoracic inlet, adrenal glands
b. thoracic inlet, diaphragm
c. cricoid cartilage, adrenal glands
d. thymus, superior surface of the liver |
|
Definition
Answer:
a. thoracic inlet, adrenal glands |
|
|
Term
Regardless of the clinical indication, all chest CT scans must display the ______on the initial image.
a. lung roots
b. aortic arch
c. pulmonary arteries
d. lung apices |
|
Definition
|
|
Term
Which of the following statements regarding the use of IV contrast in the assessment of lung, mediastinal masses and lung cancer diagnosis is TRUE?
a. IV contrast is generally ineffective for the identification of hilar masses
b. IV contrast can differentiate lung cancers from pneumonia, as the latter enhance brightly on scanning
c. contrast is effective for delineating mediastinal masses from surrounding mediastinal vessels
d. neither lung infiltrates nor intraparencyhymal lung cancers will enhance with the use of iodinated contrast |
|
Definition
Answer:
c. contrast is effective for delineating mediastinal masses from surrounding mediastinal vessels |
|
|
Term
The_____is a thin membrane that lines the abdominal cavity from the diaphragm to the pelvis
a. mesentery
b. peritoneum
c. omentum
d. pleura |
|
Definition
|
|
Term
Compared with a polyethylene glycol regimen, a CT colonoscopy bowel preparation consisting of oral hydration with a cathartic for colon contraction produces:
a. a drier colon
b. fluid pools in the transverse colon
c. more abdominal crampin
d. large pockets of trapped gas |
|
Definition
|
|
Term
Which one of the following is NOT an anatomic structure contained in the mediastinum?
a. pleurae
b. aorta
c. trachea
d thymus |
|
Definition
|
|
Term
Diffuse or interstitial lung disease is assessed at the level of the :
a. alveoli
b. secondary lobules
c. bronchioles
d. acini |
|
Definition
Answer:
b. secondary lobules |
|
|
Term
For routine abdominal and pelvic scans, the preferred rate of dlivery of intravenous contrast is ____cc/sec:
a. 1-2
b. 2-3
c. 3-4
d. 4-5 |
|
Definition
|
|
Term
Which one of the following statements regarding CT scanning of the spleen is TRUE?
a. the spleen shows uniform enhancement during the arterial phase
b. the spleen shows a stripe-like enhancement during the portal venous phase
c. routine abdominal protocols are generally used for spleen imaging
d. the spleen appears more dense than the liver on unenhanced scans |
|
Definition
Answer:
c. routine abdominal protocols are generally used for spleen imaging |
|
|
Term
A Hounsfield value of +10 likely represents a/an:
a. fibroid uterus
b. diverticular abscess
c. endometiral tumor
d. ovarian cyst |
|
Definition
|
|
Term
The_____is/are NOT located in the peritoneal cavity.
a. spleen
b. ileum
c. kidneys
d. gallbladder |
|
Definition
|
|
Term
The superior mesenteric artery supplies blood to all of the following areas EXCEPT the:
a. pancreatic head
b. sigmoid colon
c. jejunum
d. ileum |
|
Definition
|
|
Term
The structures of the colon that give it a "pillow-like" appearance are called the:
a. haustra
b. segmental ligaments
c. transverse ligaments
d. tenia coli |
|
Definition
|
|
Term
The opening through which the descending aorta passes through the diaphragm is called the aortic_____.
a. arch
b. hilum
c. hiatus
d. sinus |
|
Definition
|
|
Term
What types of reconstruction algorithms are used for routine chest CT scans with multislice scanners
a. detail/high resolution
b. standard/smooth
c. standard/lung
d. smooth/high resolution |
|
Definition
Answer:
d. smooth/high resolution |
|
|
Term
Scan protocols for evaluating the pancreas can be used for all of the following indications EXCEPT:
a. jaundice
b. acute cholecystitis
c. gastric cancer
d. hepatitis |
|
Definition
|
|
Term
The liver has a dual blood supply through the _______and _____.
a. hepatic artery, portal vein
b. celiac trunk, aorta
c. portal hepatis, main portal vein
d. celiac trunk, hepatic artery |
|
Definition
Answer:
a. hepatic artery, portal vein |
|
|
Term
Preparation for breath-holding during the CT exam may encompass all of the following EXCEPT:
a. propping frail patients up with pillows
b. instructing patients to take numerous rapid, shallow breaths 5 minutes before the scan
c. assessing the patient's ability to sustain a breath-hold for 30 seconds
d. instructing patients who cannot hold their breath to breathe slowly |
|
Definition
Answer:
b. instructing patients to take numerous rapid, shallow breaths 5 minutes before the scan |
|
|
Term
| Using __________ reconstruction filter would decrease the appearance of noise in a CT image. 1. no 2. a sharp 3. a smooth a. 1 only b. 2 only c. 2&3 d 3 only |
|
Definition
|
|
Term
| A___________ scan uses only a single projection. 1. conventional, or serial 2. helical 3. localizer a. 1 only b. 2 only c. 3 only d. 1,2, |
|
Definition
|
|
Term
| Which of the following statements is FALSE regarding 3D SSD? a. helical image data is well suited for 3D SSD because there is minimal misregistration or gaps b. the volume data, from which the 3D SSD is generated, is created by combining transverse, sagittal, and coronal reconstructions c. the tissue surface may be selected by using a threshold value equal to the tissue's CT number d. patient motion during the scan is detrimental to the quality of the 3D images. |
|
Definition
|
|
Term
| Which type(s) of storage media may hold CT image data? 1. internal hard disk 2. CD 3. re-writable optiacal disk a. 1 only b. 2 only c. 3 only d. 1,2, and 3 |
|
Definition
|
|
Term
| __________may have to be edited from the data set to get a diagnostic MIP of a CTA exam. a. lodinated contrast media b. vessels of interest c. air d. bones |
|
Definition
|
|
Term
| Which of the following is NOT an advantage of a helical study compared to a conventional, serial CT study? a. minimal anatomical misregistration sometimes caused by inconsistent breath-holdin b. shorter total exam time c. can retrospectively reconstruct a slice at any arbitrary position d. offers the best image quality for a brain exam |
|
Definition
|
|
Term
| Which of the following utilizes convolution? 1. 3D SSD 2. Fourier transform 3. filtered back projection a. 1 only b. 2 only c. 3 only d. 1,2, &3 |
|
Definition
|
|
Term
| In which technique are tissues other than the surface of a structure excluded by setting a threshold value and eliminating pixels above or below that threshold? a. volume rendering b. multi-planar reconstruction c. maximum intensity projection d. 3D shaded surface display |
|
Definition
|
|
Term
| From which of the following can the most diagnostic multiplanar reconstructions be generated? 1. stacked transverse images from a helical scan 2. stacked transverse images from a conventional, serial scan 3. stacked localizer images a. 1 only b. 2 only c. 3 only d. 1,2, &3 |
|
Definition
|
|
Term
| The actual attenuation data measured by the detectors from all projections during a scan is contained in CT ______data. 1. image 2. convolved 3. raw a. 1 only b. 2 only c. 3 only d. 1, 2, |
|
Definition
|
|
Term
| Which of the following is TRUE regarding the slice thickness of an image reconstructed from a helical scan? 1. on a multi-row detector scanner, the thickness is equal to the beam collimation 2. on a single-row detector scanner, the thickness is equal to the beam collimation 3. on a single-row detector scaneer, the thickness can be varied retrospectively a. 1 only b. 2 only c. 2&3 d. 1,2, &3 |
|
Definition
|
|
Term
| A retrospective reconstruction, in which the reconstruction field-of view is varied, uses: 1. a reconstructed image in the sagittal plane b. CT raw data c. more photons d. CT image data |
|
Definition
|
|
Term
| Which of the following is common to both a localizer scan and a conventional, serial CT scan? a. they both produce digital images b. the patient table moves at a constant velocity c. they both produce cross-sectional images d. the x-ray tube makes complete 360 degree rotations |
|
Definition
|
|
Term
| Which of the following statements is TRUE? 1. the amplified electrical signal obtained from the detectors must be digitized 2. digital CT images are numerical representations of cross-sectional anatomy 3. digital signals may be formed by sampling analog signals at discrete time intervals a. 1 only b. 2 only c. 3 only d. 1, 2, & 3 |
|
Definition
|
|
Term
| ________is the mathematical process used by single-row detector scanners to reconstruct CT images from raw data. a. weighted averaging b. filtered back projection c. the fourier transform d. integration of the area under the curve |
|
Definition
|
|
Term
| 3D shaded surface displays are performed on CT: 1 image data 2. raw data 3. attenuation profiles a. 1 only b. 2 only c. 3 only d. 1,2,&3 |
|
Definition
|
|
Term
| A pixel is a : a. bright artifact on a film b. single 3D volume element within a volume of anatomical data c. single 2D picture element within the image plane d. range of gray levels on a CT image |
|
Definition
|
|
Term
| The pencil thin section of the x-ray fan beam that strikes a single detector is called a : a. line b. projection c. view d. ray |
|
Definition
|
|
Term
| A kernal is a : a. component in the x-ray tube b. post-processing filter applied to image data c. type of detector d. filter applied to the CT rawdata |
|
Definition
| Answer: d. filter applied to the CT rawdata |
|
|
Term
| An increase in ______does NOT occur in the resulting images when applying a sharp, or high-pass reconstruction filter during the image reconstruction of CT raw data. 1. contrast resolution 2. edge enhancement 3. the appearance of noise a. 1 only b. 2 only c. 3 only d. 1,2, |
|
Definition
|
|
Term
| ________is the mathematical process used by single-row detector scanners to reconstruct CT images from raw data. a. weighted averaging b. filtered back projection c. the fourier transform d. integration of the area under the curve |
|
Definition
|
|
Term
| CTA images come from a ________scan. 1. conventional, or serial 2. helical 3. localizer a. 1 only b. 2 only c. 3 only d. 1,2, |
|
Definition
|
|
Term
| If an image matrix has 360 rows and 360 columns, how many pixels are there in the image? a. 21,600 b. 129,600 c. 259,200 d. 379,800 |
|
Definition
|
|
Term
| The ______determines the intensity of the laser beam in a laser camera. 1. intensifying grid 2. pixel values in the image data 3. magnifying power of the lens. a. 1 only b. 2 only c. 3 only d. 1,2, |
|
Definition
|
|
Term
| Which of the following is a reconstruction technique applied to the raw data after the primary reconstruction has already been accomplished? a. maximum intensity projection b. volume rendering c. retrospective reconstruciton d. multi-planar reconstruction |
|
Definition
| Answer: c. retrospective reconstruction |
|
|
Term
| What does convolution do to the image quality when it is added to the back projection reconstruction process? a. normalizes the attenuation coefficients to ensure tissues are displayed with correct CT numbers b. increases the number of projections thereby recucing streaking artifacts c. improves contrast resolution by reducing scatter radiation d. enhances important characteristics of attenuation profiles thus reducing stereak and star artifacts. |
|
Definition
|
|
Term
Which of the following may occur during the interscan delay of a conventional, or serial, CT scan performed on a continuous rotation scanner? 1. the table is incremented 2. the tube continues to rotate in the same direction as during the scan 3. the tube assembly makes a 360 degree rotation 4. all of the above |
|
Definition
|
|
Term
______allows helical data to be converted into planar raw data. a. retrospective reconstruction b. interpolation c. cone beam reconstruction d. 1,2, &3 |
|
Definition
|
|
Term
What is the most common type of film used for recording CT images? a. thermal b. double emulsion c. single emulsion d. paper |
|
Definition
|
|
Term
A helical scan performed on a 64 slice MDCT scanner is reconstructed with: a. back projection b. simple reconstruction because it is a single projection scan c. no reconstruction filter d. cone beam reconstruction |
|
Definition
|
|
Term
______yields an image that appears 3D but also shows anatomical details above and below the 3D surface. a. SSD b. VR c. MIP d. multiplanar reconstruction |
|
Definition
|
|
Term
MDCT scanners capable of collecting 64 slices in a single rotation do NOT: a. perform conventional CT scans b. perform helical CT scans c. use filtered back projection as their method of image reconstruction d.perform localizer scans |
|
Definition
|
|
Term
MIP images: a. are most frequently used for visualizing air-filled spaces b. can NOT be run in a cine loop c. are most accurate when a large volume of interest is selected d. do NOT demonstrate detail beneath the brightest pixel |
|
Definition
|
|
Term
Multi-planar reconstructions are performed on which of the following? 1. image data 2. raw data 3. attenuation profiles 4. all of the above |
|
Definition
|
|
Term
The ______move(s) during a helical scan on a third-generation scanner. a. x-ray tube b. patient table c. detector elements d. all of the above |
|
Definition
|
|
Term
A CT system manufacturer has a scanner in which the focal spot of the x-ray beam can move to two, slightly separated, distinct locations. What benefit does thef dual focal spot provide compared to an identical scanner possessing a single focal spot? a. the number of projections is doubled b. the number of rays in a single projection is doubled c. the patient does is halved d. all of the above |
|
Definition
|
|
Term
On a third-generation single-row detector scanner, if there are 715 detectors and there are 900 projections in a full rotation, how many samples of attenuation data are collected for the raw data of a single slice if the scan calls for an overscan of a 400 degree rotation? a. 286,000 b. 643,500 c. 715,000 d. 845,000 |
|
Definition
|
|
Term
A smooth, or low-pass, reconstruction filter is typically NOT selected for a(n) _______exam. a. pituitary b. kidneys c. liver d. internal auditory canals |
|
Definition
|
|
Term
In a __, the highest pixel values from a stack of CTA images are projected along many "rays". a. SSD b. MIP c. PR d. VR |
|
Definition
|
|
Term
The x-ray beam used in CT scanning is _______the patient's tissues. a. reflected off of b. attenuated by c. generated by d. all of the above |
|
Definition
|
|
Term
Which of the following are possible results of partial voluming? a. decreased sharpness of edges b. misleading CT numbers c. improvement in resolution d. all of the above e. a&b |
|
Definition
|
|
Term
Which of the following has the highest patient dose assuming all other parameters are the same? a. mA=200, rotation time=2 seconds b. mA=200, rotation time=1 second c. mA=150, rotation time=3 second d. mA=400, rotation time =1 second |
|
Definition
|
|
Term
CT numbers________would appear black if a window width of 400 and a window level of -100 are used. a. above +200 b. below -300 c. below -200 d. above +100 |
|
Definition
|
|
Term
If a calcification with a CT number of +300 appears pure white on an image, which of the following could be the window width and window level selected? 1. wl=0, ww=500 2. wl=+300, ww=500 3. wl=+100, ww=1000 a. 1 only b. 2 only c. 3 only d. 2&3 |
|
Definition
|
|
Term
Which of the following determinants of CT imge quality is responsible for how grainy or speckled a CT image appears? a. resolution b. linearity c.noise d. contrast |
|
Definition
|
|
Term
Whichi of the following statements is FALSE? a. magnification requires raw data b. increasing magnification increases resolution c. magnification decreases the size of displayed anatomy. d. all of the above |
|
Definition
|
|
Term
If a thin slice is used, which of the following would help reduce the apparent image noise? a. reduced reconstruction field of view b. increased matrix c. inreased mAs d.increased kVp |
|
Definition
|
|
Term
A CT Number Calibration Tst should be performed: a. weekly b.annually c. monthly d. daily |
|
Definition
|
|
Term
Which of the following is a reason to increase the pitch? 1. a greater volume of anatomy cn be covered in a given time 2. a given volume of anatomy can be covered faster 3. radiation dose to the patient can be increased a. 1 only b. 2 only c. 1&2 d. 2&3 |
|
Definition
|
|
Term
Which of the following is FALSE about the spatial resolution of an image? 1. resolution is dependent on matrix size 2. resolution is dependent on reconstruction FOV 3. resolution is dependent on scanned FOV a. 1 only b. 2 only c. 3 only d. 1, 2, and 3 |
|
Definition
|
|
Term
An increase in_______ will result in hardening ofan x-ray beam. 1. tissue density 2. tissue thickness 3. kVp a. 1 only b. 2 only c. 3 only d. 1, 2, &3 |
|
Definition
|
|
Term
If the slice thickness s changed fro 5 mm to 7mm and all other parameters are held constant, ____% more photons will be used in making the slice. a. 30 b. 40 c. 60 d.80 |
|
Definition
|
|
Term
Which of the following will result in an increased voxel size? 1. decreased reconstruction FOV 2. increased slice thickness 3. increased matrix a. 1 only b. 2 only 3. 2&3 4. 1,2, &3 |
|
Definition
|
|
Term
If a reconstruction FOV of 32cm and a 512X512 matrix are used, the pixel size is _____mm. a. 0.35 X 0.35 b. 0.625 x 0.625 c. 1.6 x 1.6 d. 3.25 x 3.25 |
|
Definition
|
|
Term
Which of the following does NOT occure when reconstruction FOV is decreased? a. spatial resolution is increased b. pixel size is increased c. noise in the image increases d. all of the above |
|
Definition
|
|
Term
Which of the following is the conversion equation from CT number to Hounsfield unit? a. CT number=0.5 HU b. CT number= (HU)² c. CT number=HU d. CT number=2 x HU |
|
Definition
|
|
Term
There are ______total pixels in a 1024 x 1024 matrix. a. 2048 b. 524,288 c. more than 1 million d. more than 2 million |
|
Definition
|
|
Term
Which of the following occurs when slice thickness is reduced? a. appearance of noise in the image increases b. the number of photons used in making the slice decreases c. partial volume averaging decreases d. all of the above |
|
Definition
|
|
Term
Increasing ________results in lowering the patient dose. 1. pitch 2. mAs 3. table increment a. 1 only b. 1&2 c. 1&3 d. 1,2,&3 |
|
Definition
|
|
Term
_______affects the CT number of water. a. no imaging parameter b. the slice thickness c. the kVp d. the mAs |
|
Definition
|
|
Term
The smalles object that can be resolved if a reconstruction FOV of 24 cm and a 512 x 512 matrix are used is ____mm. a. 0.47 b. 1.00 c. 2.13 d. 3.57 |
|
Definition
|
|
Term
If the radiologist requires 2mm thick contiguous slices through the pituitary and 2.4 cm of coverage, ___slices are necessary? a. 8 b. 10 c. 12 d. 13 |
|
Definition
|
|
Term
Which of the following is NOT a result of reducing the reconstruction FOV? a. improved spatial resolution b. increased appearance of image noise c. anatomical structures appear smaller d. all of the above |
|
Definition
|
|
Term
Which of the following parameters affects the contrast of a CT image? a. reconstruction interval b. mAs c. kVp d. CT number |
|
Definition
|
|
Term
Which of the following parameters is responsible for partial volume averaging? a. matrix size b. kVp c. slice thickness d. patient dose |
|
Definition
|
|
Term
On MDCT, the final reconstructed slice thickness is determined by the: a. number of rows of detectors and the size of the detectors whose attenuation data gets combined b. pitch c. reconstruction interval d. collimation |
|
Definition
|
|
Term
The distance that the table travels between slices is called: a. table increment b. collimation c. rotation d. reconstruction interval |
|
Definition
|
|
Term
A set of images is reconstructed with a 150 mm reconstruction FOV. Keeping all other parameters constant, a second set of images is reconstructed with a 300 mm reconstruction FOV, and then magnified so that the anatomical structures in the first and second set appear the same size. Which of the following statements is FALSE? 1. the resolution of the second set of images is better than the first set 2. the apparent noise in the second set of images is more pronounced than the first set 3. the patient dose of the first set of images is higher than the second set. a. 1&2 b. 1&3 c. 2&3 d. 1, 2, &3 |
|
Definition
|
|
Term
Which of the following is NOT directly proportional to mAs? a. the mean energy of the x-ray photons leaving the tube b. the number of x-ray photons leaving the x-ray tube c. x-ray tube heating d. dose to the patient |
|
Definition
|
|
Term
Which of the following parameters causes helical slices to be reconstructed so they overlap? a. table increment b. reconstruction interval c. pitch d. collimation |
|
Definition
|
|
Term
Which of the following is the expected result of a CT Number Calibration Test performed on a water phantom? a. 0 +/- 3 b. 0 +/-5 c. 1000 +/-5 d. 100 +/-3 |
|
Definition
|
|
Term
On a conventional, or serial, Ct scan, if we want 5mm slices with 1mm of overlap, the talbe increment should be____mm. a. 10 b. 6 c. 4 d. 1 |
|
Definition
|
|
Term
Which of the following parameters allows adjacent slices to be overlapped without increasing the dose to the patient? a. reconstruction interval b. slice thickness c. table increment d. pitch |
|
Definition
|
|
Term
Which of the following can be changed retrospectively? 1. the slice thickness from an MDCT helical scan 2. the slice overlap from a single-row detector scanner helical scan 3. the slice thickness from a single row-detector scanner helical scan a. 1&3 b. 1&2 c. 2&3 d. 1, 2, &3 |
|
Definition
|
|
Term
Which of the following values for pitch would stretch the x-ray helix the most? a. 1.5 b. 1.0 c. 0.8 d. 0.5 |
|
Definition
|
|
Term
The ____determines how penertrating the x-ray beam will be. a. kVp b. rotation time c. mA d. pitch |
|
Definition
|
|
Term
Which of the following would be used in a high resolution study of the temporal bones? a. reduced slice thickness b. reduced reconstruction FOV c. sharp reconstruction filter d. all of the above |
|
Definition
|
|
Term
Which of the following would be used to better visualize low contrast resolution? 1. decreased mAs 2. sharp reconstruction filter 3. narrow window width a. 1 only b. 2 only c. 1 & 2 d. 3 only |
|
Definition
|
|
Term
For a given distance of coverage, which of the following is TRUE? 1. as reconstruction FOV increases, patient dose increases 2. as pitch increases, patient dose decreases 3. as slice thickness increases, patient dose decreases a. 1 only b. 2 only c. 3 only d. 2&3 |
|
Definition
|
|
Term
_______the window _____will make the image appear darker so that the bony structures can be evaluated. a. increasing, width b. decreasing, level c. decreasing, width d. increasing, level |
|
Definition
|
|
Term
Follwoing the HIPAA guidelines, you may give a ptient's medical information to another employee: a. if it is in plain sight on the Ct console and the employee has already read it b. if the employee is realated to the patient c. only if it is needed to do their job d. to joke about the patient's excessive weight |
|
Definition
|
|
Term
If the mA of a 2 second brain scan is doubled and all other parameters are not changed the dose is: a. doubled b. unaffected c. halved d. quadrupled |
|
Definition
|
|
Term
Which of the following is the complete name of the laborator test known as PTT? a. thromboplastin time b. prothrombin time c. partial thromboplastin time d. partial prothrombin time |
|
Definition
|
|
Term
Renal function refers to which of the following organs? a. gall bladder b. kidney c. liver d. spleen |
|
Definition
|
|
Term
In all states, patients are required by law to sign consent forms for the following reason: a. permission to admisister contrast b. permission to perform a surgical procedure c. signed consent forms are not required by law in every state d. permission to administer sedation |
|
Definition
|
|
Term
Which of the following values for prothrombin time are considered outside the normal range? 1. 12 sec 2. 20 sec 3. 30 sec a. 1 only b. 2 only c. 3 only d. 2 & 3 |
|
Definition
|
|
Term
_____mm Hg is within the normal diastolic pressure range for adults. a. 40 b. 80 c. 120 d. 140 |
|
Definition
|
|
Term
The result of which of the following lab tests may impact the decision to administer IV contrast media? a. BUN b. creatinine c. PT d. all of the above |
|
Definition
|
|
Term
On a multi-row detector scanner, a radiation penumbra may be found: a. on every other slice b. only on the trailing edges of the slices c. on every slice d. only on the first and last slices of the slice volume |
|
Definition
|
|
Term
On a single-row detector scanner, which of the following does NOT decrease the patient dose? a. decreasing the scan time while leaving the mA constant b. decreasing the slice thickness while covering the same anatomical region c. reformat the data instead of re-scanning d. increasing the pitch |
|
Definition
|
|
Term
Which of the following is the correct action to take if the patient arrives with obvious head trauma, expecting a CT of the brain, but the paperwork requests a pelvic CT? a. perfom only a scan of the pelvis b. request clarification from the ordering physician c. perform both exams d. perform only a scan of the brain |
|
Definition
|
|
Term
During a CT scan, the patient must be monitored: a. visually and verbally b. occasionally c. by a nurse d. by a pulse oximeter |
|
Definition
|
|
Term
Which of the following does NOT minimize the radiation dose to the patient? a. decreasing the distance from the x-ray tube to the patient b. filtration of the low energy photons from the x-ray beam c. increasing the pitch d. pre-patient collimation |
|
Definition
|
|
Term
For x-ray radiation, which of the following is TRUE? a. 1 rem=1 rad b. 1 rem= 1 Gy c. 1 rad= 1Gy d. 1 rad= 1Sv |
|
Definition
|
|
Term
A normal pulse rate for an infant is _____BPM. a. 140 b. 85 c. 60 d. 30 |
|
Definition
|
|
Term
The most important consideration in the care of an unconscious patient is to ensure that: a. air passages are clear b. the body temperature is decreased c. fluids are maintained d. no medications are administered |
|
Definition
|
|
Term
Which of the following statements is TRUE if the patient history was taken at the time of scheduling? a. a claustrophobic patient can arrive for the scan prepared with a prescription sedative b. time can by saved the day of the exam by skipping the screening process c. if it has been determined that the patient has no prior illness or conditions, monitoring is unnecessary. d. all of the above |
|
Definition
|
|
Term
The human embryo/fetus is most sensitive to radiation: a. in the second trimester b. in the first trimester c. equally in all trimesters d. in the third trimester |
|
Definition
|
|
Term
Which of the following could be the dose experienced by the pituitary from a typical CT brain scan? a. 9 rads b. 5 mGy c. 2 rads d. 1 mGy |
|
Definition
|
|
Term
If there is no overlap or gap between adjacent slices of a CT scan, CTDI __________MSAD. a. is less than b. equals c. is much greater than d. is slightly greater than |
|
Definition
|
|
Term
A normal adult has ______respirations per minute. a. 5-8 b. 12-20 c. 20-30 d. 30-40 |
|
Definition
|
|
Term
A blood urea nitrogen level of ___mg/dl is considered outside the normal range. 1. 10 2. 18 3. 32 a. 1 only b. 2 only c. 3 only d. 2&3 |
|
Definition
|
|
Term
Which of the following tests is NOT an indication of renal function? 1. BUN 2. creatinine 3. PTT a. 1 only b. 2 only c. 3 only d. 2&3 |
|
Definition
|
|
Term
Which of the following conditions may be an indication NOT to use IV contrast media? a. previous serious reaction to contrast media used during another diagnostic procedure b. allergy to iodine c. renal impairment d. all of the above |
|
Definition
|
|
Term
Which of the following is NOT a typical indication of shock? a. grayish skin tone b. convulsive seizures c. hypotension d. tachycardia |
|
Definition
|
|
Term
Platelets are small: a. implants b. detector elements responsible for captuing attenuated photons c. cell fragments necessary for blood coagulation d. catheters used for administering contrast media |
|
Definition
|
|
Term
Which of the following reduces patient dose at the expense of increasing the apparent noise in the image? a. kVp b. pitch c. table increment d. mAs |
|
Definition
|
|
Term
A 25 year old female is scheduled for a CT scan of the sinuses. She is not absolutely certain that she is not pregnant and it has been three weeks since her last menstrual period. Which of the following is the best course of action? a. perform the exam immediately, while she is experiencing sinus problems b. psotpone the proceduer until she is more certain of her condition c. cancel the procedure indefinitely d. suggest she get an MRI instead |
|
Definition
|
|
Term
Which of the following is a possible long-term effect of repeated exposure to radiation? a. cataracts b. cancer c. decrease in life expectancy d. all of the above |
|
Definition
|
|
Term
CPR must be administered to a cardiac arrest victim within a maximum of ______before there is a risk of brain damage. a. 1 b. 4 c. 8 d. 12 |
|
Definition
|
|
Term
Which is NOT a standard infection control precaution to use with all patients? a. use of an N95 respirator b. wash hands after touching a patient c. disposal of needle in sharps container d. wear gloves when starting an IV |
|
Definition
|
|
Term
Which of the following statements is TRUE? a. respirators are not allowed in the CT suite b. pulse oximeters are allowed in the CT suite c. the patient should be removed from the CT suite to treat cardiac arrest d. all of the above |
|
Definition
|
|
Term
A patient about to get a scan of her sinuses may wear: a. eyeglasses so she can see the technologist b. a nose ring c. her new belt with a large silver buckle d. earrings, to look her best |
|
Definition
|
|
Term
Which of the following is TRUE regarding a radiation penumbra? 1. it occurs because the collimator is broken 2. it is radiation that extends outside of the imaging region 3. it is accounted for in the calculation of the MSAD a. 1 only b. 2 only c. 2 &3 d. 3 only |
|
Definition
|
|
Term
A creatinine level of 3.1 mg/dl indicates the: a. kidneys are not removing waste products from the urine b. patient is not a good candidate to receive IV contrast media c. value is below the normal range d. all of the above |
|
Definition
|
|
Term
Making up the ARRT Standard of Ethics are the Code of Ethics which is ______, and the Rules of Ethics which are_______. a. a law, variable depending upon the state you're in b. a conduct guideline, variable depending upon the state you're in c. a conduct guidline, enforceable d. a law, recommended job descriptions |
|
Definition
|
|
Term
When reviewing the images from a helical CT scan, a subtle, suspicious area of possible pathology is noticed. What could be done to better visualize the suspicious are WITHOUT increasing the dose to the patient? a. re-scan the region using thinner slices b. re-scan the region using a lower pitch c. retrospectively reconstruct the slices so that they overlap d. all of the above |
|
Definition
|
|
Term
Which of the following vital signs is considered abnormal? a. adult pulse of 75 BPM b. pediatric pulse of 110 BPM c. adult blood pressure of 160/100 d. oral temperature of 97° |
|
Definition
|
|
Term
To modify a standard CT protocol so that it is appropriate for children, which of the following should be decreased? 1. pitch 2. kVp 3. mAs a. 1 only b. 1 & 2 c. 1 & 3 d. 2 & 3 |
|
Definition
|
|
Term
Which of the following may result from exposing an embryo to x-ray radiation a. mental retardation b. miscarriage c. deformities d. all of the above |
|
Definition
|
|
Term
Which of the following is a result of injecting a hypertonic solution into the vascular space? a. there is a net movement of water into the vascular space b. there is a net meovement of contrast media out of the vascular space c. there is a net movement of water out of the vascular space d. there is nothing noteworthy about injecting a hypertonic solution into the vascular space |
|
Definition
|
|
Term
Which of the following is a common patient reaction to IV contrast media? a. warmth at the injection site b. headache c. nausea d. all of the above |
|
Definition
|
|
Term
Low osmolar contrast media: a. typically has the same concentration of particles as the blood b. typically has a higher concentration of particles compared to blood c. tends to cause more adverse reactions than high osmolar contrast media d. is never used in CT |
|
Definition
|
|
Term
Barium sulfate oral contrast media would be selected instead of iodonated oral contrast media because: 1. it passes through the GI tract more quickly 2. the trauma patient may have a perforated bowel 3. the contrast media stays more dense in the distal GI tract a. 1 only b. 2 only c. 2&3 d. 3 only |
|
Definition
|
|
Term
Which of the following may help to reduce adverse reactions resulting from the administration of IV contrast media? a. use high osmolar contrast media b. administer an antihistamine prior to the IV contrast injection c. increase the rate of injection d. all of the above |
|
Definition
|
|
Term
Which of the following oral contrast agents is better for opacifying the distal small intestine? 1. an ionic iodinated contrast agent 2. a non-ionic iodinated contrast agent 3. barium sulfate a. 1 only b. 2 only c. 3 only d. 1 & 2 |
|
Definition
|
|
Term
Iodinated IV contrast agents perfuse normal: a liver tissue b. brain tissue c. thecal sac d. lymph nodes |
|
Definition
|
|
Term
Which of the following is NOT a typical adverse reaction to oral contrast media used in CT? a. diarrhea b. abdominal cramping c. flatulence d. hives |
|
Definition
|
|
Term
A delay of about ____seconds after the start of the IV contrast injection should be used for a helical scan of the neck. a. 20 b. 35 c. 50 d. 75 |
|
Definition
|
|
Term
If there is doubt regarding the sterility of the contrast media, the contrast media must be: a. shaken b. diluted c. heated d. discarded |
|
Definition
|
|
Term
The most common catheter size used in CT is_____gauge. a. 12 to 14 b. 15 to 17 c. 18 to 22 d. 23 to 25 |
|
Definition
|
|
Term
Viscosity is a measure of a fluid's: a. atomic weight b. thickness c. temperature d. injection rate |
|
Definition
|
|
Term
The viscosity of IV contrast media can be reduced by: a. shaking b. stirring c. aerating d. heating |
|
Definition
|
|
Term
Why is the cephalic vein a less desirable site for injection than the basilic vein? a. it is usually a very small vein with poor blood flow b. the blood must transverse through the vessels in the head before reaching the heart c. it is a deep vein and not easily catheterized d. flow may be impeded as the patient's arms are raised |
|
Definition
|
|
Term
A difference in density of ______HU between the aorta and the inferior vena cava would indicate the non-equilibrium phase of enhancement a. 43 b. 35 c. 25 d.8 |
|
Definition
|
|
Term
There substantial enhancement of the liver compared to tumors during the ______phase, but during the ______phase, there is the possibility of tumor enhancement, which may make hepatic tumors isodense with liver tissue. a. bolus, equilibrium b. non-equilibrium, equilibrium c. non-equilibrium, bolus d. equilibrium, non-equilibrium |
|
Definition
|
|
Term
Iv contrast agents used in CT increase the attenuation of the x-ray beam due to the concentration of _____in the agent. a. iodine b. glucose c. meglumine d. barium |
|
Definition
|
|
Term
The definition of osmolality is the _____the contrast agent solution a. thickness of b. measure of dissociation of c. concentration of molecular particles in d. rate of injection of |
|
Definition
|
|
Term
The osmolality of plasma is ____mOsm/kg. a. 175 b. 235 c. 285 d. 325 |
|
Definition
|
|
