Ch 16 Computed Tomography Questions with
Accurate Answers
Algorithm correct answer A sequence of computer operations for accomplishing a
specific task
Annotation correct answer Printed comment or label added to the digital image
Array Processor correct answer A component of the computed tomography
computer that is dedicated to performing the calculations needed for image
reconstruction
Automatic Tube Current Modulation correct answer Essentially automatic
exposure control in CT; it provides ongoing adjustment of the mA based on
patient size and tissue characteristics, maintaining image quality while reducing
dose, especially for small patients
Beam-Hardening Artifact correct answer As the x-ray beam passes through the
patient, especially through bone, the lower-energy photons are filtered out,
resulting in beam hardening; results in inaccurate CT numbers
Bowtie Filter correct answer The filter frequently used in CT with a shape and
composition that serve to make the energy level of the photons reaching the
detectors more consistent
Cone Beam correct answer The shape of the beam in CT imaging as the number of
slices being imaged per revolution increases and the x-ray beam is opened
, Contrast Resolution correct answer Used to describe the ability of the imaging
system to distinguish between small objects that attenuate the x-ray beam
similarly in digital imaging
CT Number (or Hounsfield Unit) correct answer Value related to the attenuation
characteristic of the tissue in the voxel, not an attenuation coefficient
CT Table correct answer May be flat or curved and can be raised and lowered to
assist the patient in getting off and on; also known as a "couch"
Data Acquisition System (DAS) correct answer Amplifies the weak signal produced
by the detector-photodiode, converts to logarithmic data, converts it from analog
to digital data, and sends it to the computer
Detector Array correct answer The physical component consisting of multiple
detectors that effectively absorb the transmitted radiation and accurately convert
it to an electrical signal for display on a computer workstation
Display Field of View (DFOV) correct answer Controls the area of anatomy seen on
the monitor in CT imaging
Edge Enhancement Filter correct answer Makes all the info in the image appear
sharper, including the noise
Electron-Beam Computed Tomography (EBCT) correct answer A fifth-generation
scanner developed for cardiac imaging, the ___ reduced scan time to as little as
50 MS, fast enough to image the beating heart
Accurate Answers
Algorithm correct answer A sequence of computer operations for accomplishing a
specific task
Annotation correct answer Printed comment or label added to the digital image
Array Processor correct answer A component of the computed tomography
computer that is dedicated to performing the calculations needed for image
reconstruction
Automatic Tube Current Modulation correct answer Essentially automatic
exposure control in CT; it provides ongoing adjustment of the mA based on
patient size and tissue characteristics, maintaining image quality while reducing
dose, especially for small patients
Beam-Hardening Artifact correct answer As the x-ray beam passes through the
patient, especially through bone, the lower-energy photons are filtered out,
resulting in beam hardening; results in inaccurate CT numbers
Bowtie Filter correct answer The filter frequently used in CT with a shape and
composition that serve to make the energy level of the photons reaching the
detectors more consistent
Cone Beam correct answer The shape of the beam in CT imaging as the number of
slices being imaged per revolution increases and the x-ray beam is opened
, Contrast Resolution correct answer Used to describe the ability of the imaging
system to distinguish between small objects that attenuate the x-ray beam
similarly in digital imaging
CT Number (or Hounsfield Unit) correct answer Value related to the attenuation
characteristic of the tissue in the voxel, not an attenuation coefficient
CT Table correct answer May be flat or curved and can be raised and lowered to
assist the patient in getting off and on; also known as a "couch"
Data Acquisition System (DAS) correct answer Amplifies the weak signal produced
by the detector-photodiode, converts to logarithmic data, converts it from analog
to digital data, and sends it to the computer
Detector Array correct answer The physical component consisting of multiple
detectors that effectively absorb the transmitted radiation and accurately convert
it to an electrical signal for display on a computer workstation
Display Field of View (DFOV) correct answer Controls the area of anatomy seen on
the monitor in CT imaging
Edge Enhancement Filter correct answer Makes all the info in the image appear
sharper, including the noise
Electron-Beam Computed Tomography (EBCT) correct answer A fifth-generation
scanner developed for cardiac imaging, the ___ reduced scan time to as little as
50 MS, fast enough to image the beating heart
