Biomedical Engineering Reference
In-Depth Information
Three-dimensional fetal surface images are very attractive. But they are
not always obtained due to lack of amniotic fluid around the fetus or an
inadequate fetal position.
There are some artifacts in 2D ultrasound [22]. Multiple reverberation
causes a band-like artifact image under the abdominal wall. The side lobes of
an ultrasonic beam causes artifact images from one side of a strong reflector
to the other. An acoustic shadow appears under a strong reflector. These
artifacts also exist in 3D ultrasound and sometimes hide a fetal image or
cause a false deformity on a 3D fetal image.
2.2.5
The Future Development of Three-Dimensional Ultrasound
Three-dimensional ultrasound is still immature and has to be developed much
more. Two main developments are expected in future 3D ultrasound. One is
real time and the other is tissue characterization.
Real-time 3D ultrasound will resolve the motion artifact problem, one
of the major problems in 3D ultrasound. Figure 2.14 shows 3D fetal images
obtained at a frame rate of 3.2 frame/s by a specially designed high-speed
3D ultrasound scanner with a real-time ultrasonic beam tracing method.
The fetus opened its mouth for a split second in conjunction with its finger
bending. Fetal movement or fetal behavior can be observed in this way. Fetal
behavior is expected to be used as the basis of a method for evaluating the
development of the motor and nervous system of the fetus. It is necessary to
Fig. 2.14.
3D fetal images obtained at the frame rate of 3.2 fps (
left
to
right
)by
a specially designed high-speed 3D ultrasound scanner. Note the mouth opening
(
center
) and an index finger bending (
right
)
