Term
in order for an xray phonton to be measured it must
1. enter the detecter chamber
2. be absorbed by the detector
3. be converted to a measurable event
A. 1only
b. 2 only
c. 3 only
d. 1,2 and 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. ananlog to digitial converter
d. host computer |
|
Definition
|
|
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
|
|
Term
which of the following is not a part of the Ct tube
a. tungsten target
b. collimator
c. rotating anode
d. filament |
|
Definition
|
|
Term
Which of the following is FALSE regarding CT systems
1. they are limited to non-oblique transverse scanning
2. they cannot generate straight coronal or sagittal image
3. Tehy have no moving parts |
|
Definition
|
|
Term
| the ____is located on the Tubes cathode and the ____target is located on teh tubes rotating anode form the electrical circuit with to which the high voltge generated by the _____ ____ ____is applied |
|
Definition
filament
tungsten target
hig voltage generator |
|
|
Term
| which set of collimators is located between teh patient and the tube |
|
Definition
|
|
Term
| the second set of collimators is located between the patient and the detectors and is called |
|
Definition
|
|
Term
| percent of total availabe xrays that actually enter the chamber which collide with the detector is called? |
|
Definition
|
|
Term
| the percent of xrays entering the chamber which collide with the detector atoms is called what |
|
Definition
|
|
Term
| the percent of xrays colliding with the detector atoms which result in a measurable electrical signal is called what? |
|
Definition
|
|
Term
| the total conversion effciency of a detector is actually the product of what three things |
|
Definition
capture efficiency
absorption efficiency
conversion efficiency |
|
|
Term
| The gantry of a modern CT system can tilt to an angle of approx ____ |
|
Definition
|
|
Term
| By using post processsing software which calculates ____ ___ ____ it is possible to generate images through virtually any arbitrary plane |
|
Definition
| multi-planar reconstruction |
|
|
Term
x-rays are used in CT because
a. they are easily produced by high frequecy generator
b. they are less harmful than the heating effects of microwave radiation
c. they penetrate the body according to specfic attenuation characteristics of each tissue
d. the FDA imposes no limit on the dose to the patient |
|
Definition
|
|
Term
most of the commands from the technologist are received by the
a. array processor
b. operators console
c. host computer
d. amplifier |
|
Definition
|
|
Term
| the ____ ____accepts the commands from the operators consule translates them into machine language and seens a code fo each command to the appropriate system |
|
Definition
|
|
Term
| the _______ increases the strength of the electrical signals obtained from the detectors. |
|
Definition
|
|
Term
| the _____ _____ reconstructs images from the signals after theary are sampled and digitized |
|
Definition
|
|
Term
xrays are produced whenever fast-moving electros collide with any form of matter because:
1. the electon splits into two xray photons of equal energy upon impact with the matter.
2. the electron loses kinetic energy which is converted into the emission of an xray photon
3. the electron converts teh electron it collides with into an xray photon
a. 1 only
b. 2 only
c. 3 only
d. 1,2 and 3 |
|
Definition
|
|
Term
| xrays are produced whenever there is a loss of ____ ____ from the incoming electron. Such ______ ____ is lost when an incoming electron collides directly with the ____ of the atom, or when it slows down when passing the ____ of the atom due to the interaction with the positive charge of that nucleus. The Two events produce ______ _____which produces x-ray photons that are useful to CT imaging. |
|
Definition
Kinetic energy
kinetic energy
nucleus
nucleus
bremsstrahlong radiation
|
|
|
Term
| The incoming electron can also collide with an electron in an inner shell of he target atom, in which case teh temporary instability of the atom causes an eletron in an outer shell to jump into the vacated position. This event causes the jumping electron to lose some energy which is converted tin the the imission of an xray photon. this type of xray is _____useful for clincial imaging |
|
Definition
|
|
Term
The MA determines the
a. quantity of xray photons
b. coeficient of attenuation
c. slice thickness
d. energy level of the xray photons |
|
Definition
|
|
Term
| the MA controls the flow of electrons from the ____ to the ____ in the CT tube. It also controls the _____ of xray photons emitted from the ____ ___. The energy level of the xray photons is controlled by the _____ which is the voltage across the _____ and the _____ |
|
Definition
cathode
anode
number
tungsten anode
kv
cathode
anode |
|
|
Term
| the _____ of ______ is dependent on the atomic number and density of a materal and the energy level of the specfic xrays irratiating that materal |
|
Definition
| coefficient of attenuation |
|
|
Term
Which of the following is a component NOT normally located in the gantry of a modern CT system
a. pre-paitient collimators
b. solid state detectors
c array processor
d xray tube |
|
Definition
|
|
Term
| the _____ ______ is the site of the reconstruction of the CT raw data into image data. |
|
Definition
|
|
Term
Tube interscan delay time refers to:
a. the time between the end of one scan and the start of the next scan during which the tube will cool
b. a quality assurance test performed daily by the technologist
c. the time required for the tube to make a compete 360degree revolution aout the gantry
d. the length of time required for the production of photons to begin after applying the voltage to the tube |
|
Definition
|
|
Term
increase______ will increase the likelihood that a given xray will penetrte a material
1. Kv
2. MA
3. Exposure time
a. 1 only
b. 2 only
c. 3 only
d. 1,2 & 3
|
|
Definition
|
|
Term
Which of the following are not commonly used on today's commercially 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
| almost all of today's commercially available Ct scanners use ______ ________ and can perform ________ ______. Most of these scanners use _____ ____ technology. Most scanners today use ____ ____ _____ instead of _____ ____ |
|
Definition
continuous rotation technology
helical scanning
slip ring
solid state detectors
xeono detectors |
|
|
Term
scatter radiation is caused by :
a. miscalibrated detector
b. xrays generated spontaneously in the ambient atmosphere
c. deflections from teh orginal trajectory of an xray photon through the patient
d. improper patient positioning |
|
Definition
|
|
Term
| scattered radiation causes _____ |
|
Definition
|
|
Term
which of the following is the standard thats used to achieve compatibility for image transfer between various imaging modalities, viewing stations and printers in a hospital
a. tcp/IP
b. T1
c. PACS
D. DICOM |
|
Definition
|
|
Term
The enourmous heat that builds up in the CT tube is caused by the :
a. intensity of the xrays emitted from the tube
b. electron beam between the cathode and the anode in the tube
c. xray 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
|
|
Term
_________ made helical imaging possible.
a. muli-row detector scanners
b. the introduction of second generation technology
c. the introduction of fourth generation technology
d. continuous rotation scanners |
|
Definition
|
|
Term
The purpose of the detector is to:
A. provide additional collimation in order to reduce scatter
b. limit the xray dose to the patient
c. capture xray photons and convert them to a measurable signal
d. amplify the measured signal |
|
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 xray photons
d. focuses xrays onto the anode target |
|
Definition
|
|
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 ___ controls the energy level or voltage potential of the electron beam between the cathode and the anode. The number of electons in the beam is controlled by the ____ ______. At a given KV setting the tube current is established by changing the resistance of the ______ _____. |
|
Definition
KV
tube current
cathode filament |
|
|
Term
Which of the following is TRUE regarding solid state detectors
1. xray 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 scanners
a. 1 only
b. 2 only
c. 3 only
d. 1,2 & 3 |
|
Definition
|
|
Term
| ____ ionizes in response to an xray conversion. ______ ____ ___ generate a flash of light which is converted to an electrical signal by means of a ______. |
|
Definition
Xenon
solid state detectors
photodiode |
|
|
Term
CT is commonly referred to as all of the following names EXCEPT:
a. computerized axial tomography
b. digital subtraction andiography
c. CAT scan
D. Computed tomography
|
|
Definition
|
|
Term
Which of the following CT scanner designs does not use an xray tube?
a. first generation CT
b. PET/CT
C. electron beam CT
D. MDCT |
|
Definition
|
|
Term
Which technology do multi-row detector scanners employ?
A. second generation
b. third generation
c. fourth generation
d. first generation |
|
Definition
|
|
Term
on a single row detector scanner, collimation:
1. controls the slice thickness
2. minimizes the xray dose to the patient
3. reduces the detection of scater radiation
a. 1only
b. 2 only
c. 3 only
d. 1,2 & 3 |
|
Definition
|
|
Term
| a ______ is any device that might need to access the images |
|
Definition
|
|
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 the detector arrays may or may not be used
a. 1 only
b. 2 only
c. 3 only
d. 1,2 and 3 |
|
Definition
|
|
Term
Collimation:
a. is accomplished by electrically blocking xrays
b. affects the scan time
c. limits the low energy xray photons and passes the high energy photons
d. is accomplisched by physically blocking xrays
|
|
Definition
|
|
Term
Collimation:
a. is accomplished by electrically blocking xrays
b. affects the scan time
c. limits the low energy xray photons and passes the high energy photons
d. is accomplisched by physically blocking xrays
|
|
Definition
|
|
Term
| the primary function of the collimation system is to control the _____ of the xray beam. |
|
Definition
|
|
Term
tungsten is used as the target material on the tubes 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
| Tungsten has a high atomic numbe of ___ which makes it avery dense atom and therefore an efficient source of xrays. The melting point of tungsten is ______. Most metals melt between ____ and ____ |
|
Definition
74
3400 degree C
300 and 1500degree C |
|
|
Term
CT images can be directly scanned in planes other than transverse by:
1. orienting the patients body part so that it is not perpencicular to the xray beam
2. tilting the gantry
3. Changing the angle that the xray beam leaves teh tube.
a. 1only
b. 1&2
c. 2&3
d. 1,2 and 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 curbe |
|
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 projections as their method of image reconstruction
d. perform localizer scans |
|
Definition
|
|
Term
The xray beam used in CT scanning is ____ the patient's tissue
a. 1 only
b. 2 only
c. 3 only
d. 1 2 & 3 |
|
Definition
|
|
Term
A retrospective reconstruction in which the reconstruction field of view is varied uses:
A. A recontructed image in the sagital plane
b. CT raw data
C. more photons
d. ct image data |
|
Definition
|
|
Term
| A _______ ______ always utilizes the unprecessed ct data. |
|
Definition
| retrospective reconstruction |
|
|
Term
| A retrospective reconstruction allow parameters such as the ___ ___ __ __, the ____, and the ____ ___to be varied and on MDCT the ___ ___ to be changed and the image reconstruction process initiated in order to form a new set of images with different characteristics that the original images. |
|
Definition
display field of view
matrix
reconstruction filter
slice thickness |
|
|
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 3 |
|
Definition
|
|
Term
the actual attenuation data measured by teh detectors from all projections during a scan is contained in CT ____data
1. image
2. convolved
3. raw
a. 1only
b. 2 only
c. 3 only
d. 1,2 & 3 |
|
Definition
|
|
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
| When a ct image is recontructed from the raw data a ______ ___ or ______ must be applied to. The first purpose of the filter is to actually represent the anatomy and remove ___and ___ artifacts, which would otherwise occur. Next depending on the type of filter selected, certain image characteristics can be enhanced. For example, a ____ ___ is used for defining structural edges and highlighting high resolution detail. ____ ____ do this at the expense of making images appear more noisey. A____ ____ is used for visualizing its subtle differences in contrast. To do this, ___ ___ minimizes the appearance of noise in an image. |
|
Definition
reconstruction filter
kernel
Star
streak
sharp filter
sharp filters
smoothe filter
smoothe filters
|
|
|
Term
a kernel is a :
a. compenent in the xray tube
b. post processiong filter applied to image data
c. type of detector
d. filter applied to the CT raw data |
|
Definition
|
|
Term
| A kernel also called______ ___or a ______ ___, is a filter which is appled to the CT ____ ___. It is not a post processing filter applied to the image data. |
|
Definition
reconstruction filter
convolution filter
raw data |
|
|
Term
Iterative reconstruction is:
a. the type of image reconstruction method in use in CT before multi row detector scanners became available
b. A complex cycle of correction calculations applied during image reconstruction in order to reduce noise in the image
C. As second reconstruction process performed after the initial reconstruction in which a set of modified parameters is use
d. Typically performed on a helical image data, to generate images in orientations other than those that can easily be directly to acquire with CT |
|
Definition
|
|
Term
| _______ ______is a fairly recent advancement in CT which has revolutionized how scans are performed and which has greatly improved patient safety. Although each manufacturer applies the technique somewhat differently, what they have in common is a repetitive comparison of either the raw data or image pixels in which data inconsistencies are identified and corrected. This acts to reduce the noise seen in the images. With less noise, the scan parameters may be adjusted to produce a lower radiation dose, thus improving patient safety. |
|
Definition
|
|
Term
From which of the following can the most diagnostic multiplanar reconstructions be generated?
1. stacked transverse images from a helical scanner
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
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
A ______ is a 2 dimensional picture element.
A 3- dimensional volume element is called a ____ |
|
Definition
|
|
Term
| SSD MIP PR and VR are all ____ _____ techniques. |
|
Definition
|
|
Term
| SSD, MIP PR and VR are all ____ _____ techniques |
|
Definition
|
|
Term
If an image matrix has 360 rows and 360 columns, how many pixels are there in the image?
a. 21600
b. 129600
c. 259200
d. 379800 |
|
Definition
|
|
Term
important clinical benefit of iterative reconstruction include:
1. ability ro reduce radiation dose without compromising image quality
2. no longer needing to perform multi-planar reconstructions.
3. reduction in noise seen in the image
a. 1 only
b. 2&3
c. 1&3
d. 1 2 & 3 |
|
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, sgital and coronal reconstructions
c. the tissue surface may be selected by using a threshold value.
D. patient motion during the scan is detrimentall to the quality of the 3D images |
|
Definition
|
|
Term
A helical scan performed on a 64 slice MDCT scanner is reconstructed with
a. back projection
b. simle reconstruction because it is a single projection scan
c. no reconstruction filter
d. cone beam reconstruction |
|
Definition
|
|
Term
A CT system manufacturer has a scanner in which the focal spot of the xray beam can move to two slightly separated distinct locations. what benefit does the duel focal spot provide compared to an identical scanner possessing a single focal spot?
1. the number of projections is doubled
2. the number of rays in a single projections is doubled
3. the patient dose is halved
a. 1only
b. 2 only
c. 3 only
d. 1,2 & 3 |
|
Definition
| the number of projections is doubled (a) |
|
|
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 & 3 |
|
Definition
|
|
Term
What does convolution do to the image quality when it is added to the back projection reconstruction process?
a. normalizes the atenuation coefficients to ensure tissues are displayed with correct CT Numbers
b. increases the number of projections thereby reducing streaking artifacts
c. imporves contrst resolution by reducing scatter radiation
d. enhances important characteristics of attunuation profiles thus reducing streak and star artifacts |
|
Definition
|
|
Term
the ____ move(s) during a helical scan on a third-generation scanner
1. xray tube
2. patient table
3. detector elements
a. 1only
b. 2 only
c. 3 only
d. 1,2 & 3 |
|
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 intnesity projection
b. volume rendering
c. retrospective reconstruction
d. multi-planar reconstruction |
|
Definition
| retrospective reconstruction (C) |
|
|
Term
A smooth, or low-pass reconstruction filter is typically Not selected fo a(n) _____ exam
a. pituitary
b. kidneys
c. liver
d. interal auditory canals |
|
Definition
|
|
Term
| A ______or ___ ___ filter enhances the edges of structural details in the image and id does so at the expense of _____ ____. |
|
Definition
sharp
high-pass
contrast resolution |
|
|
Term
| a ____ or ____ ___ filter helps to visualize the contrast between structures with subtle density differences. this filter should be used for the _____, ______, ______ |
|
Definition
smooth
low pass
kidney
liver
pituitary |
|
|
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 holding
b. shorter total exam time
c. can retrospectively reconstruct a slice at any aritrary position
d. offers teh best image quality for a brain exam |
|
Definition
|
|
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. 1only
b.2only
c. 3only
d. 1,2 &3 |
|
Definition
|
|
Term
which of the following utilizes convolution?
1. 3D SSD
2. Fourier transform
3. Filter back projection
a. 1only
b. 2only
c. 3 only
d. 1,2 & 3 |
|
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. Multi-Planar reconstruction |
|
Definition
|
|
Term
| _____ is the process of applying a filter to the raw data during the image reconstruction calculation. |
|
Definition
|
|
Term
______ may have to be edited from the data set to get a diagnostic MIP of a CTA exam
a. iodinated contrast media
b. vessels of interest
c air
d. bones |
|
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
c. maximum intinsity projection
D. 3D shaded surface display |
|
Definition
| 3 D shaded surface display (D) |
|
|
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. 1only
b. 2only
c. 3 only
d. 1,2 &3 |
|
Definition
|
|
Term
multi-planar reconstructions are performed on which of the following
1 image data
2. raw data
3. attenuation profiles
a. 1only
b. 2only
c. 3 only
d. 1,2 3 |
|
Definition
|
|
Term
______ allows helical data to be converted into planar raw data.
A. Retrospective reconstruction
b. interpolation
c. cone beam reconstruction
d. convolution |
|
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 400 degrees rotation?
a. 286000
b. 643500
c. 715000
d. 845000 |
|
Definition
|
|
Term
| what is the equation to determine the projections per degree? |
|
Definition
| the number of projections/360degree (full rotaion) |
|
|
Term
The _____ determines the inensity 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. 1only
b. 2only
c. 3only
d. 1,2 & 3 |
|
Definition
| pixel values in the image data (B) |
|
|
Term
The pencil thin section of the wray fan beam that strikes a single detector is called a:
a. line
b. projection
c. view
d. ray |
|
Definition
|
|
Term
| Each vantage point from which the anatomy can be "viewed" is called a ______. |
|
Definition
|
|
Term
| Each projection is made up of many xray beams called _____ |
|
Definition
|
|
Term
3d shaded surface displays are preformed on CT:
1. image data
2. raw data
3. attenuation profiles
a. 1only
b. 2only
c. 3 only
d. 1,2 & 3 |
|
Definition
|
|
Term
Which of the following is TRUE regarding the slice thickness of an image reconstruction 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 ro detector scanner the thickness can be varied retrospectively
a. 1only
b. 2only
c. 3 only
d. 1,2 &3 |
|
Definition
|
|
Term
| ________ ________ is the ability to image adjacent tissues that have similar mass density and effective atomic density. |
|
Definition
|
|
Term
Contrast resolution can be improved by 1)
2)
3)
4)
5)
6) |
|
Definition
1)smaller field of view
2) thicker slices
3)smaller matrix size
4) larger pixel size
5)high mas
6)low pass filter smooth filter |
|
|
Term
Water should always equal____
Bone Should equal ____ |
|
Definition
|
|
Term
| CT ______ refers to assigning the correct Hounsfield unit to a specific material being scanned. |
|
Definition
|
|
Term
| _______ occurs because an insufficient number of photons reach the detectors. |
|
Definition
|
|
Term
Noise is reduced by
1)
2)
3) |
|
Definition
1)increasing the mAs
2)slice thickness
3) pixel size |
|
|
Term
| ______ is the ability of the Ct scanner to assign the same housfield number to the same tissue each time |
|
Definition
|
|
Term
| A ______ _____ is created when the housfield numbers are not accurate for consistent material because of beam divergence |
|
Definition
|
|
Term
| _____ _____ represents the ability to discriminate objects of varying density, a small distance apart, against a uniform background. |
|
Definition
|
|
Term
| _____ ____ is a measure of how small and object can be imaged using CT. |
|
Definition
|
|
Term
Spatial resolution can be improved by
1)
2)
4)
5)
6) |
|
Definition
1)using thin slice thickness
2)an image matrix with small pixel size
3)reconstruction filters such as high frequency convolution
4) small detector size |
|
|
Term
| ______ _____ refers to the ability of the scanner to image moving objects effectively |
|
Definition
|
|
Term
| temporal resolution can be improved by 1) |
|
Definition
1) using a technique called half scan algorithm
2) acquiring the data set during certain heart cycles (the rest cycle or the R wave |
|
|
Term
| the _____ ____ or _____ is the area on the anode that the electrons strike and create x-radiation |
|
Definition
|
|
Term
| in third generation CT scanners the focal spot is related to ____ ____ |
|
Definition
|
|
Term
true of false
the smaller the focal spot the better the spatial resolution |
|
Definition
|
|
Term
| modern CT scanners use what is described as ___ ____ geometry |
|
Definition
|
|
Term
| modern CT scanners more often use ______ detectors |
|
Definition
|
|
Term
| ____ controls the quantity of xrays |
|
Definition
|
|
Term
| the display field of view is always ___ to or _____ than the scan field of view |
|
Definition
|
|
Term
| The thinner the slice the more _____ that is noticeable on the image because of fewer photons available when scanning the thinner slice |
|
Definition
|
|
Term
| scanning with thinner slices improves ___ ____ ____ |
|
Definition
|
|
Term
| a _____ filter or ______ is applied to the raw data to remove blurring and artifacts |
|
Definition
|
|
Term
| _____ is referred to as the quality of the xray beam |
|
Definition
|
|
Term
| typical Kvp settings in Ct are |
|
Definition
|
|
Term
| Kvp controls the _____ of the image |
|
Definition
|
|
Term
| the higher the Kvp the lower the _____ ____ |
|
Definition
|
|
Term
| the _____ _____ controls the contrast of the image and describes a range of CT number represented on a gray scale |
|
Definition
|
|
Term
| the ____ _____ determines where the range extends on the gray scale |
|
Definition
|
|
Term
| when lower energy photons are obsorbed by the patient and higher energy photons pass through the body the average power of the remaining photons increases and the beam becomes _____ |
|
Definition
|
|
Term
Beam hardening artifacts
1)
2)
3) |
|
Definition
1) affected by mAs and kvp
2) depend on the patient size and anatomy
3) affected by Ct contrast agents |
|
|
Term
| _____ _____ _____ occurs when similar tissue types share the same voxel |
|
Definition
|
|
Term
| Partial volume averaging artifacts can be reduced by |
|
Definition
| scanning with thinner slices |
|
|
Term
| _____ _____ often appear as ghosting on the image |
|
Definition
|
|
Term
| when the heart is at rest it is known as the _____ phase |
|
Definition
|
|
Term
| Diastole occurs during the __ peak wave of the ECG cycle |
|
Definition
|
|
Term
| ____ ____ appear on the CT image a s streak emanating from the object |
|
Definition
|
|
Term
| When impurities are present in the x-ray tube of a CT scanner, a short circuit can occur causing ____ ____ |
|
Definition
|
|
Term
| Tube arcing usually results from ___ ___ __ |
|
Definition
|
|
Term
| there are two types of tub arcing ___ and ___ the tube. |
|
Definition
|
|
Term
| inside tube arcing happens when the voltage arcs to ________ with in the tube |
|
Definition
| minute particles of tungsten |
|
|
Term
| Outside tube arcing occurs ___ __ ___ __ __ ___ ___ |
|
Definition
| In the oil in the tube housing |
|
|
Term
| an artifact that appears as an obvious band across the entire image or as an overall degradation of the image is ____ |
|
Definition
|
|
Term
| ____ ____ usually are seen only with 3rd generation CT scanners, and are a result of faulty detectors |
|
Definition
|
|
Term
| ___ ____ artifacts appear as streaks that originate from the body structures that vary in tissue density |
|
Definition
|
|
Term
| ____ ___ filters can enhance the edges of structures by diminishing the blur usually associated with edge gradient artifacts, although the use of high pass filter results in increased noise in the image |
|
Definition
|
|
Term
edge gradient artifacts can be reduced by
1)
2)
3) |
|
Definition
1)using thinner slices
2)increased data sampling rates
3) detectors with small apertures |
|
|
Term
| ct head - position patient ___ tuck chin so the ___ line is parallel to the axial scan plane. table height si positioned at the level of the ____ ____ __ |
|
Definition
| supine oml orbital meatal line, external auditory meatus |
|
|
Term
| when scanning a head the sfov is ___cm and a dfov is __cm |
|
Definition
|
|
Term
| head scan parameters should include anatomy from the ___ ___ through the ___ of the ___ the gantry angled to the___ |
|
Definition
foramen magnum
vertex skull
oml |
|
|
Term
| the selected KVP for Head is ____ with MA in a range from ___ to ___ the acquired slices should be _mm thick with the table mving in _mm increments |
|
Definition
|
|
Term
| for the soft tissue of the brain a ___ algorithm is applied. the WW range is __to __ with the WL is set at __ to __ |
|
Definition
standard
80 to 100
20 to 40 |
|
|
Term
| to visualize the boney detail of the head a ___ algorithm is applied and a WW of ____ to ____ and a WL of __ to __ |
|
Definition
sharp
2000 to 2500
200 to 300 |
|
|
Term
| the routine head CT scan is acquired in the ___ plain |
|
Definition
|
|
Term
Injection parameters for routine head ct exam: infused at ___/s
for a total of ___ml with and initial delay of _ to _ min |
|
Definition
|
|
Term
| routine neck - position patient ____ tell the patient not to ____ or ____ during the exam. |
|
Definition
|
|
Term
| table height for routine neck should begin the routine neck scout at the ____ and 0ed at the __ of __ the scan range should be from _____ of the ___ down through ___ ___ |
|
Definition
EAM
top of head
top of head
mid chest |
|
|
Term
| a routine neck is performed in a ____ scan mode. a ___cm head sfov is used with a Dfov of __ to __cm |
|
Definition
|
|
Term
| the scan range of the routine neck should start at the ___ to the ____ |
|
Definition
|
|
Term
| routine neck the scanner automatically sets the mA between ___ and ___. the Kvp should be set to ___ |
|
Definition
|
|
Term
| routine neck slice thickness should be ___ to ___mm |
|
Definition
|
|
Term
| the algorithm or reconstruction filter for routine neck should be set to ___ or ___ |
|
Definition
|
|
Term
| the WW for routine neck should be ___ to ___ and a WL at __ |
|
Definition
|
|
Term
| injection parameters for routine neck are ___ to __ ml of contrast and an injection rate of ___ to __ ml/s. injection delays range for __ to __s |
|
Definition
|
|
Term
| routine c_spine scout 0 the scanner at the ___. raise the table so that the lateral laser light bisects the ___ ___ plane along the cervical region |
|
Definition
|
|
Term
| the scan mode for routine cspin is set to ___ the SFOv is set to ___cm and the dfov is set to __cm |
|
Definition
|
|
Term
| the scan range for a routine neck should start at ___ of skull and ending at ____ inferiorly |
|
Definition
|
|
Term
technical factors for a routine neck
kvp is set to ___ to ___
mAs ranging from ___ to ___ utilizing auto MA |
|
Definition
|
|
Term
| routine cspine generally require a reconstruction set to __mm. trauma should be set to __mm thickness and spacing. the pitch will range from __ to ___ |
|
Definition
|
|
Term
| routine cspine reconstruction filters will be ___ or __ and an addional set of __ or ___. |
|
Definition
|
|
Term
| routine cspine requires a WW of ___ to ___ and a WL of __ to __ the bone algorithm WW is ____ with a WL of ___ |
|
Definition
|
|
Term
| routine chest positon the patient ___ arms ___. center the patient using the laser light by raising the table height to the level that bisects the ___ ___ |
|
Definition
supine
above head
midcoronal plane |
|
|
Term
| the scout of a routine chest should demonstrate anatomy from the top of ___ through the ___ bases and into the upper ___ |
|
Definition
|
|
Term
| the routine chest is acquired in the ___ mode |
|
Definition
|
|
Term
| routine chest sfov is set to ___ at __cm the dfov ___ depending on the patients size |
|
Definition
|
|
Term
| routine chest start the scan line above the ___ ___ and extend inferiorly through the lung bases into the upper abdomen stopping at the ___ ___ of the ___ |
|
Definition
lung apices
upper poles of the kidney |
|
|
Term
technical factors for routine chest
kvp ___
MA between___ and ___ |
|
Definition
|
|
Term
| routine chest image acquisition is set to __mm slice thickness with __mm interval spacing the pitch is in the range of ___ to ___ |
|
Definition
|
|
Term
| the routine chest algorithm is set to ___. if High resolution images are required select the __ or __ algorithm |
|
Definition
|
|
Term
| two different ww and WL are used when viewing a chest CT. A WW of ___ and WL of ___ display the lungs and their air filled spaces while a WW of ___ and WL of ___ display the mediastinal and other soft tissues |
|
Definition
|
|
Term
| injection parameters for routine chest. a delay of __ to __ sec common injection rate of __ to __ml p/s |
|
Definition
|
|
Term
CTA of the thoracic aorta maybe clinically indicated to rule out
1)
2)
3) |
|
Definition
dissection
surgical mapping
aneurysm eval |
|
|
Term
| cta chest is set up like __ __. the scan parameters should be set up with a max __mm slice thickness with a __mm interval |
|
Definition
|
|
Term
| chest CTA to visualize opacified vasculature of the lungs and aorta the ww is ___ and the wl ___ |
|
Definition
|
|
Term
for a chest CTA PE study the monitor location should be in the ___ ____
the trigger threshold is __ to __ HU and a post threshold of _to_ sec |
|
Definition
pulmonary artery
90-100
3 to 5 |
|
|
Term
| IV contrast for a CTA PE study should use __ to __ ml of contrast followed by a __ to __ ml of saline and an injection rate of __ml per sec |
|
Definition
|
|
Term
| for CTA of the thoracic Aorta the monitor location is the ___ ___ the trigger threshold is __ to __HU with a post threshold delay of _to _ sec |
|
Definition
ascending aorta
100 to 150
3 to 5 |
|
|
Term
| for CTA of the thoracic Aorta __ to ___ml of contrast should be used followed by __ to __ml of saline and injection rate of __ml per sec |
|
Definition
|
|
Term
| the scan mode for the abdomen is ___ |
|
Definition
|
|
Term
| set up the abdomen start the scan a few inches below the ___ |
|
Definition
|
|
Term
| the SFOV for the abdomen is set to ___ or __cm |
|
Definition
|
|
Term
| for an abdomen scan start the scan from above the ___ of the ___ and end at the ___ ___ if the scan requires the pelvis extend the scan through the ___ __ |
|
Definition
dome of the liver
iliac crest
symphysis pubis |
|
|
Term
scan parameters for the abdomen pelvis:
Kvp ___
mAs ___
slice thickness ___mm
interval ___mm |
|
Definition
|
|
Term
pitch for routine ab/pelvis is __ to __
A __ or ___ algorithm
WW of __ to__
WL of __ to __
WL ___ |
|
Definition
.56 -1.2
Standard soft
350 -400
40 - 60 |
|
|
Term
| Iv contrast for routing abd/pelvis is injected at __to __ml per sec for a total of __ to __ ml of contrast |
|
Definition
|
|
Term
| a scan delay for abd/pelvis studies requires a __ to __ sec delay for scanning the pelvis only a delay of __sec |
|
Definition
|
|
Term
| how many lobes are in the right and left lungs |
|
Definition
|
|
Term
| true or false the mediastinum is divided in to w portions |
|
Definition
| true, superior and inferior |
|
|
Term
| the arch of the aorta, the artic branches and all structures that pass from the neck into the thorax are found where? |
|
Definition
|
|
Term
| the inferior mediastinum is segmented into ____, ____ and _____ parts |
|
Definition
| Anterir , middle posterior |
|
|
Term
the anterior mediastinum contains only
1)
2)
3) |
|
Definition
1)connective tissue
2)fat
3) lymph nodes |
|
|
Term
the middle mediastinum holds
1)
2)
3)
4)
5)
6) |
|
Definition
1)heart
2)the root of the ascending aorta
3)the pulmonary arter
4)superior vena cava
5)inferior vena cava
6)four pulmonary veins |
|
|
Term
the posterior mediastinum contains
1)
2)
3)
4)
5) |
|
Definition
1)Azygos vein
2) hemiazygos vein
3)descending thoracic aorta
4)esophagus
5)thoracic duct |
|
|
Term
the great vessels assocated with the heart are
1)
2)
3) |
|
Definition
1) aorta and its branches
2)vessels of the pulmonary truck
3) vena cava |
|
|
Term
| which vessel is the larges artery in the body |
|
Definition
|
|
Term
the arch is divided into 3 sections
1)
2)
3) |
|
Definition
1)ascending aorta
2)arch
3)descending aorta |
|
|
Term
| the ascending aorta is position in the _____ mediastinum, the arch is in the ____mediastinum and the descending aorta is in the posterior mediastinum |
|
Definition
|
|
Term
| the ascending aorta begins from the outflow of the _____ _____ of the heart. the ____ _____ valve separates the aorta from the ____ ____ |
|
Definition
left ventricle
aortic semilunar valve
Left ventricle |
|
|
Term
| the ___ and _____ _____ arteries branch off the aorta almost immediatley |
|
Definition
|
|
Term
| the ___ ___ is located to the left of both the esophagus and the trachea |
|
Definition
|
|
Term
| the aortic arch travels inferiorly becoming the ____ ____. the transition occurs at the level of the __ and ____ ___ ___ |
|
Definition
descending aorta
4 and 5 thoracic vertebrae |
|
|
Term
three arteries branch from the aortic arch, 1)
2)
3) |
|
Definition
1)brachiocephalic artery
2)left common carotid artery
3)left subclavian artery |
|
|
Term
| the ______ ___ is a single artery and is the largest and most anterior branch off the aortic arch |
|
Definition
|
|
Term
| the brachiocephalic artery bifurcates into the _____ ____ and the ____ ____ |
|
Definition
right common carotid artery
right subclavian artery |
|
|
Term
| the middle branch off the aortic arch is the ____ ____ ___artery |
|
Definition
|
|
Term
| the ____ _____ artery is the third branch off the aortic arch |
|
Definition
|
|
Term
| the ____ ____ is located approximately at the level of the 8th thoracic vertebra |
|
Definition
|
|
Term
| the ____ _____ is the main pumping chamber of the heart and has the thickest walls of all the chambers |
|
Definition
|
|
Term
| the ___ ___ is the most posterior aspect of the heart |
|
Definition
|
|
Term
| Most of the anterior surface of the heart is formed by the ____ ____ |
|
Definition
|
|
Term
| the right ventricle receives blood from the ___ ___ through the ___ valve and ejects that blood into the _____ ___ through the ____ ____ ___ |
|
Definition
right atrium
tricuspid
pulmonary trunk
pulmonary semilunar valve |
|
|
Term
| the ___ and ____ ___ artery supply blood to the heart |
|
Definition
|
|
Term
| the left main coronary artery bifurcates into the ____ ____ ___ and the ___ coronary arteries |
|
Definition
left anterior descending
circumflex |
|
|
Term
| pulmonary circulation is provided by the ____ ___, which orginates from the ___ ventricle |
|
Definition
|
|
Term
| at the level of the aortic arch the pulmonary trunk bifurcates into the ___ and ____ ____ arteries |
|
Definition
|
|
Term
| the ____ ___ ___ and the ____ ___ ___ are the largest venous structures In the human body |
|
Definition
superior vena cava
inferior vena cava |
|
|
Term
| the superior vena cava orginates in the ___ ____ from the union of the __ and ____ _____ veins |
|
Definition
superior mediastinum
left and right brachiocephalic |
|
|
Term
| the larynx become the ____ at the level of C6 |
|
Definition
|
|
Term
| the main duct of the lymphatic system is the ____ ___ |
|
Definition
|
|
Term
| the ____ vein ascends within the thorax to the level of the 4th thoracic vertebrae then enters the ___ __ ___ |
|
Definition
|
|
Term
| the ____ gland is responsible for developing and maintaining the immune system |
|
Definition
|
|
Term
| the ____ nerve controls the movement of the diaphragm |
|
Definition
|
|
Term
| the _____ aorta begins at the aortic hiatus of the diaphragm . this vessel then bifurcates into the ___ ___ arteries at the level of L4 |
|
Definition
|
|
Term
the abdominal aorta produces several branches
1
2
3
4
5
6
7 |
|
Definition
1 celiac
2 superior mesenteric
3 renal
4 gonadal
5 lumbar
6 inferior mesenteric
7 median sacral |
|
|
Term
| the first branch off the abdominal aorta occurs at the superior margin of the first lumbar vertebra. this branch is the ___ artery |
|
Definition
|
|
Term
the celiac artery divides into 3 other arteries
1
2
3 |
|
Definition
1 hepatic
left gastic
splenic |
|
|
Term
| the ___ ___ artery is the smallest branch of the celiac artery. it provides blood to the ___ |
|
Definition
|
|
Term
| the ____ artery is the middle branch of the celiac artery. |
|
Definition
|
|
Term
the hepatic artery produces several other arteries
1
2
3 |
|
Definition
cystic
gastroduodenal
right gastric |
|
|
Term
| after entering the porta hepatis the hepatic artery bifurcates into the ___ and ___ ____ arteries |
|
Definition
|
|
Term
| the largest and the longest branck of the celiac is the ____ artery |
|
Definition
|
|
Term
| at approx. the superior portion of the 2nd lumbar vertebra the paired ___ arteries can be found |
|
Definition
|
|
Term
| the ____ arteries are slightly lower than the renal arteries. these arteries are referred to as ovarian arteries in women and testicular in men |
|
Definition
|
|
Term
| the ____ ___ arteries are the result of the bifurcation of the abdominal aorta at the L4 |
|
Definition
|
|
Term
| the common iliac continue inferiorly to approx. l5 into the ___ and ___ ____ arteries. |
|
Definition
|
|
Term
| the inferior vena cava is formed by the union of the ____ and ___ ___ ___ veins at the level of the L5 |
|
Definition
|
|
Term
the Inferior vena Cava contains valves
true or false |
|
Definition
|
|
Term
| the hepatic portal system of veins is responsible for transporting blood to the gastrointestinal system to the ____ |
|
Definition
|
|
Term
the veins of the hepatic portal system include
1)
2)
3) |
|
Definition
1) inferior mesenteric
2) superior mesenteric
3) splenic |
|
|
Term
| the superior mesenteric and the splenic veins merge to form the ___ vein |
|
Definition
|
|
Term
| unlike most other anatomical structures, the liver receives blood from ___ sources |
|
Definition
|
|
Term
| the ___portal vein supplies 75% and the _____ artery supplies 25% of the blood to the liver |
|
Definition
|
|
Term
the portal triad includes
1
2
3 |
|
Definition
1 portal vein
2 main hepatic artery
3 common bile duct |
|
|
Term
the small intestine is divided into 3 sections
1
2
3 |
|
Definition
|
|
Term
| after beginning at the stomach the ____ loops about 25 Cm in the shape of a C encircling the pancreas before continuing as the ___ |
|
Definition
|
|
Term
| the jejunum transitions into the ____ and empties into the ____ |
|
Definition
|
|
