GE Voluson 730, Руководство по обслуживанию

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GE M
EDICAL
S
YSTEMS
- K
RETZTECHNIK
U
LTRASOUND
D
IRECTION
105844, R
EVISION
1 V
OLUSON
® 730 S
ERVICE
M
ANUAL
5-8 Section 5-2 - General Information
5-2-2-2 3D Image Presentation:
The basic technique for 3D image presentation is to combine the 2D 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 3D-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 ultrasound mode.
Several techniques can be used to aid the human observer in understanding the resulting 2D image as
a representation of a three-dimensional object. One is to rotate the volume of data, and present the
resulting sequence of 2D 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.
5-2-2-3 3D Rendering:
The 3D (volume) rendering is a calculation process to visualize certain 3D-structures of a scanned
volume by means of a 2D-image. The gray value for each pixel of the 2D-image is calculated from the
voxels along the corresponding projection path (analyzing beam) through the volume. The render
(calculation) algorithm, surface or transparent mode, determines how 3D-structures are visualized.
With the MagiCut function it is possible to cut off “3D artifacts” which hide regions that are of interest for
the diagnostic purpose.
Figure 5-4 Principle of Volume Rendering
PIXEL
VOXEL
Y
X
Z
PRINCIPLE: VOLUME RENDERING
PROJECTION WAY
2D - D
ISPLA
Y
VOLUME -
BLOCK
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