GE LOGIQ E9 Service Manual page 212

GE
D 5535208-100, R
IRECTION
5-2-8-6-1 4D Data Collection and Reconstruction
2D (B-Mode) (B-Mode) gray scale images may be reconstructed. The acquisition of volume data sets
is performed by sweeping 2D (B-Mode) (B-Mode)-scans with special transducers (called 4D-
transducers) designed for the 2D (B-Mode)-scans and the 4D-sweep.
Images are spatially registered, using internal probe position sensing and a position control to ensure
geometric accuracy of the 4D data.
2D (B-Mode) ultrasound imaging modes are used to view a two dimensional cross-sections of parts of
the body. For example in 2D (B-Mode) gray scale imaging, a 2 dimensional cross-section of a 3-
dimensional soft-tissue structure such as the heart is displayed in real time. Typical, the user of an
ultrasound machine manipulates the position and orientation of this 2D (B-Mode) cross-section in real
time during an ultrasound exam.
By changing the position of the cross-section, a variety of views of the underlying structure are obtained,
and these views can be used to understand a 3-dimensional structure in the body.
To complete survey a 3-dimensional structure in the body, it is necessary to collect 2D (B-Mode) images
which span a volume containing the structure. One way is to sweep the imaging cross-section by
translating it in a direction perpendicular to the cross-section. Another example method is to rotate the
cross section about a line contained in the cross section. The LOGIQ E9 Ultrasound System uses the
automated so called C-Scan for the motion perpendicular to automated B-scan. Once a representative
set of 2D (B-Mode) cross-sections are obtained, standard reconstruction techniques can be used to
construct other 2D (B-Mode) cross-sections, or to view the collection of the cross-sections as a 4D
images.
5-2-8-6-2 4D Image Presentation
The basic technique for 4D image presentation is to combine the 2D (B-Mode) cross–sections into an
image which represents how the volume of the data would appear from a particular viewing direction.
The mathematics behind this feature is called 4D-rendering. Such combined images are called
projections, because the data from the volume is projected onto a flat 2-dimensional surface, e.g. the
ultrasound system display. This technique can be applied to any 2D (B-Mode) ultrasound mode.
Several techniques can be used to aid the human observer in understanding the resulting 2D (B-Mode)
image as a representation of a three-dimensional object. One is to rotate the volume of data, and
present the resulting sequence of 2D (B-Mode) projections to the observer. The changing direction of
observation helps the observer to separate the features in the volume according to their distance from
the observer.
5-2-8-7 Volume Navigation
Using a position sensor attached to the probe, Volume Navigation Fusion (V Nav) lets you import a pre-
acquired Ultrasound, CT or MR DICOM volume dataset and register it to the live Ultrasound image. As
a result, you can view live Ultrasound scanning simultaneously with the corresponding multi-planar
reformatted (MPR) slice from the pre-acquired dataset.
In addition, you can use V Nav as a type of "GPS" positioning marker to track an anatomy of interest.
V Nav is available in B-Mode, Color Flow, PDI, and Contrast Modes; it is not available while in 3D/4D
or when timeline modes are active. Biopsy capability is available while in V Nav.
5-2-8-8 Contrast Imaging
The LOGIQ E9 is designed for compatibility with commercially available Ultrasound contrast agents.
Because the availability of these agents is subject to government regulation and approval, product
features intended for use with these agents may not be commercially marketed nor made available
before the contrast agent is cleared for use. Contrast related product features are enabled only on
ultrasound systems for delivery to an authorized country or region of use. It is not currently approved for
use in the United States.
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Section 5-2 - LOGIQ E9 description
LOGIQ E9 S M
ERVICE ANUAL