PET/CT EXAM 1 QUESTIONS AND
ANSWERS (GRADED A)
The basic premise of computed tomography is to create images in a variety of anatomic
planes that show ____. - ANSWER-internal structures free of superimposition
These display the patient's anatomy in full and precise detail - ANSWER-Slices
Pivotal point where no motion occurs in conventional tomography is called _________. -
ANSWER-fulcrum
Divides the body into an inferior and superior plane? - ANSWER-transverse
Areas of high density in CT image appear ______________ - ANSWER-white
These control brightness and contrast __________and _________. - ANSWER-window
width; window level
Hounsfield unit is based on ____________ - ANSWER-density
These improve the relevance and diagnostic quality of a scan for each patient's
condition__________. - ANSWER-axial and coronal images
What generation of scanner made spiral or helical motion possible? - ANSWER-Sixth
generation
Before the data acquired in the scan can be used, the ____must be processed through
a series of steps to produce what we recognize as a useable CT image. - ANSWER-raw
data
Refers to the way in which the x-ray beam is emitted from the x-ray tube housing,
passes through the patient, and is acquired by the CT detectors - ANSWER-Beam
geometry
In what kind of scanning is an entire volume of data is acquired without the motion of
the x-ray tube stopping? - ANSWER-Spiral or helical scanning
The ________ is the mounted framework that surrounds the patient as the table moves
during acquisition. - ANSWER-gantry
The impact of the _____on the anode during x-ray production generates an enormous
amount of heat. - ANSWER-high energy electrons
, The ___setting of the CT scanner controls the movement of the table through the gantry
and is the distance the table travels during one revolution of the x-ray tube. - ANSWER-
pitch
"beam pitch" and is calculated as...... - ANSWER-table mvmt per rotation/beam width
When the pitch ________, patient dose ________ because of shorter exposure to the x-
ray beam. - ANSWER-increases; decreases
Tomography - ANSWER-a technique for displaying a representation of a cross-section
through a human body or other solid object using x-rays or ultrasound
Characteristic xrays - ANSWER-when an atom in the target of the x-ray tube has been
ionized and then the inner shell electron is removed, leaving the atom ionized; when
outer shell electrons drop in to fill this lower shell vacancy
Trans axial tomography - ANSWER-a type of view in CT that distinguishes between
body tissue
The________, ________, and ____________are found inside the gantry, as well as the
generator, in most systems. - ANSWER-x-ray tube, cooling system, and data acquisition
system
Measure the x-ray attenuation after the beam has passed through the patient, are
located in a panel array opposite the x-ray tube. - ANSWER-Gas ionization/ scintillation
detectors
Collimation limits the amount of x-ray exposure to the patient by focusing the beam to
only the __ and _________to improve image contrast. - ANSWER-anatomy of interest
and reduce scatter
A localizer image is essential for every CT scan, and is also called a___, ______,
_____, _______, or _________. - ANSWER-scout, topogram, pilot, scanogram, or
survey
22. Scout lengths are measured in ___________. - ANSWER-millimeters
Where is AP scout tube positioned? - ANSWER-Above patient
Where is lateral scout tube positioned? - ANSWER-90 degrees from AP
A _____reduces the likelihood of patient motion during the scan, as well as problems
that arise when patients must hold their breath multiple times. - ANSWER-helical scan
25. The _______must be slightly larger than the anatomical area of interest. -
ANSWER-scan FOV
ANSWERS (GRADED A)
The basic premise of computed tomography is to create images in a variety of anatomic
planes that show ____. - ANSWER-internal structures free of superimposition
These display the patient's anatomy in full and precise detail - ANSWER-Slices
Pivotal point where no motion occurs in conventional tomography is called _________. -
ANSWER-fulcrum
Divides the body into an inferior and superior plane? - ANSWER-transverse
Areas of high density in CT image appear ______________ - ANSWER-white
These control brightness and contrast __________and _________. - ANSWER-window
width; window level
Hounsfield unit is based on ____________ - ANSWER-density
These improve the relevance and diagnostic quality of a scan for each patient's
condition__________. - ANSWER-axial and coronal images
What generation of scanner made spiral or helical motion possible? - ANSWER-Sixth
generation
Before the data acquired in the scan can be used, the ____must be processed through
a series of steps to produce what we recognize as a useable CT image. - ANSWER-raw
data
Refers to the way in which the x-ray beam is emitted from the x-ray tube housing,
passes through the patient, and is acquired by the CT detectors - ANSWER-Beam
geometry
In what kind of scanning is an entire volume of data is acquired without the motion of
the x-ray tube stopping? - ANSWER-Spiral or helical scanning
The ________ is the mounted framework that surrounds the patient as the table moves
during acquisition. - ANSWER-gantry
The impact of the _____on the anode during x-ray production generates an enormous
amount of heat. - ANSWER-high energy electrons
, The ___setting of the CT scanner controls the movement of the table through the gantry
and is the distance the table travels during one revolution of the x-ray tube. - ANSWER-
pitch
"beam pitch" and is calculated as...... - ANSWER-table mvmt per rotation/beam width
When the pitch ________, patient dose ________ because of shorter exposure to the x-
ray beam. - ANSWER-increases; decreases
Tomography - ANSWER-a technique for displaying a representation of a cross-section
through a human body or other solid object using x-rays or ultrasound
Characteristic xrays - ANSWER-when an atom in the target of the x-ray tube has been
ionized and then the inner shell electron is removed, leaving the atom ionized; when
outer shell electrons drop in to fill this lower shell vacancy
Trans axial tomography - ANSWER-a type of view in CT that distinguishes between
body tissue
The________, ________, and ____________are found inside the gantry, as well as the
generator, in most systems. - ANSWER-x-ray tube, cooling system, and data acquisition
system
Measure the x-ray attenuation after the beam has passed through the patient, are
located in a panel array opposite the x-ray tube. - ANSWER-Gas ionization/ scintillation
detectors
Collimation limits the amount of x-ray exposure to the patient by focusing the beam to
only the __ and _________to improve image contrast. - ANSWER-anatomy of interest
and reduce scatter
A localizer image is essential for every CT scan, and is also called a___, ______,
_____, _______, or _________. - ANSWER-scout, topogram, pilot, scanogram, or
survey
22. Scout lengths are measured in ___________. - ANSWER-millimeters
Where is AP scout tube positioned? - ANSWER-Above patient
Where is lateral scout tube positioned? - ANSWER-90 degrees from AP
A _____reduces the likelihood of patient motion during the scan, as well as problems
that arise when patients must hold their breath multiple times. - ANSWER-helical scan
25. The _______must be slightly larger than the anatomical area of interest. -
ANSWER-scan FOV
