1.1 Scan acquisition and user interface basics
Table 1: Scan acquisition and user interface terms
Generic description
GE names
The portion of the user interface where scans are prescribed
Scan Settings
Other portions of the user interface, such as where reconstructed
images are viewed
Patient tabs or File Man‐
ager
CT localizer radiograph (i.e. the scanned projection radiograph, of‐
ten acquired by the CT system to allow the user to prescribe the
start and end locations of the scan range)
Scout
Axial scan mode: Data acquisition while the patient table remains
stationary; the table position may be incremented between X-ray
exposures to collect data over a longer z axis range.
Axial
Helical or Spiral scan mode: Data acquisition while the patient ta‐
ble is continuously moving along the z axis.
Helical
Dynamic scan mode - single detector width: Data acquisition at
multiple time points over the same anatomic location(s) while the
patient table remains stationary; X-ray exposure can be continuous
or intermittent
Cine or zero interval Axial
Dynamic scan mode - multiple detector widths: Data acquisition at
multiple time points over the same anatomic location(s) while the
patient table cycles back and forth between designated start and
end locations in order image a region wider than the detector
Not used on this system
Interventional CT - Intermittent X-ray exposures
Not used on this system
Interventional CT - Continuous X-ray exposures
Not used on this system
Table increment (mm) per 360 degree rotation of the X-ray tube
(axial scan mode)
Scan Interval
Table feed per 360 degree rotation of the X-ray tube (helical scan
mode)
Speed (mm/rot)
Field of measurement: Diameter of the circular region within the
scan plane over which projection data are collected. Nominally
equal to the diameter of the primary beam at isocenter in the axial
plane.
Scan Field of View (SFOV,
cm)
Tube current: Number of electrons accelerated across an X-ray
tube per unit time, expressed in units of milliampere (mA)
mA
Tube current-time product: The product of tube current and expo‐
sure time per rotation, expressed in units of milliampere • seconds
(mAs). In axial scan mode, this is equal to tube current × (scan an‐
gle ÷ 360) × rotation time. In helical scan mode, this is equal to
tube current × rotation time.
Shown as read only in the
mA mode menu under Re‐
lated Settings
Revolution CT User Manual
Direction 5480385-1EN, Revision 1
682
1 Lexicon
