5-36 Image Optimization 
5.10 3D/4D 
NOTE:  3D/4D imaging is largely environment-dependent, so the images obtained are 
provided for reference only, not for confirming diagnoses. 
5.10.1 Overview 
Ultrasound data based on three-dimensional imaging methods can be used to image any 
structure where a view can’t be achieved by standard 2D-mode to improve understanding 
of complex structures. 
4D provides continuous, high volume acquisition of 3D images. 4D adds the dimension of 
“movement” to a 3D image by providing continuous, real-time displays. 
 Mode definition 
z  Smart 3D 
The operator manually moves the probe to change its position/angle when 
performing the scanning. After the scanning, the system carries out image 
rendering automatically, and then displays a frame of 3D image. 
z  Static 3D 
Posit the probe at a fixed place; the probe automatically performs the scanning. 
After the scanning is completed, the system carries out image rendering, and 
then displays a frame of 3D image. 
z  4D 
The probe performs the scanning automatically. During the scanning, the system 
renders 3D images in real time, and all 3D images are displayed in real time. 
 Ter ms 
z  VR: a three-dimensional content. 
z  Volume data: the image data set of a 3D object rendered from 2D image 
sequence. 
z  3D image: the image displayed to represent the volume data. 
z  View point: a position for viewing volume data/3D image. 
z  Section image: tangent planes of the 3D image obtained by algorithm. As shown 
in the figure below, XY-paralleled plane is C-section, XZ-paralleled plane is B-
section, and YZ-paralleled plane is A-section. The probe is moved along the X-
axis. 
z  ROI (Region of Interest): a volume box used to determine the height and width of 
scanning volume. 
z  VOI (Volume of Interest): a volume box used to determine the area of a sectional 
plane for 3D imaging.