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Diagnostic Ultrasound Imaging Technology

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					Diagnostic ultrasound is an ultrasound-based diagnostic medical imaging
technique used to visualize muscles, tendons and many internal organs to
capture their size, structure and any pathological lesions using real-
time tomographic images.       Ultrasound has been used by radiologists
and sonographers to image the human body for many years and has become
one of the most widely used diagnostic tools in modern medicine. The
technology is relatively inexpensive and portable, especially when
compared with other techniques, such as digital radiography magnetic
resonance imaging and computed tomography.


  Diagnostic ultrasound is a noninvasive medical test that helps
physicians diagnose and treat medical conditions. Ultrasound images of
the musculoskeletal system provide pictures of muscles, tendons,
ligaments, joints and soft tissue throughout the body.       Diagnostic
ultrasound is also used to visualize fetuses during routine and emergency
prenatal care. Such diagnostic applications used during pregnancy are
referred to as obstetric sonography.      The diagnostic ultrasound
involves exposing a targeted part of the body to high-frequency sound
waves to produce pictures of the inside of the body. Ultrasound exams do
not use ionizing radiation. Nonetheless, care should be taken to use low
power settings and avoid pulsed wave scanning of the fetal brain, unless
specifically indicated in high-risk pregnancies.       Because ultrasound
images are captured in real-time, they can show the structure and
movement of the body's internal organs, as well as blood flowing through
blood vessels.       Diagnostic ultrasound scanners have different
Doppler-techniques to visualize arteries and veins. The most common is
color Doppler or power Doppler, but also other techniques are used to
show blood flow in an organ. By using pulsed wave Doppler or continuous
wave Doppler blood flow, velocities can be calculated.        Diagnostic
ultrasound has the advantage of not needing direct contact with the inner
limbs of the body. Consequently, the transducer diagnostic ultrasound
part can be moved and angulated for the best possible scan view. Typical
diagnostic ultrasound parts consist of front-end, beam former, back-end
and application blocks.       The front-end block diagnostic ultrasound
part contains the transducer, the transducer elements switching system,
the transmitter power amplifier, the low noise input amplifier and the
analog to digital converter. The beam forming is achieved by a factory
programmed integrated circuit diagnostic ultrasound part.        The back-
end diagnostic ultrasound part includes various imaging reconstruction
and enhancement algorithms. Color Doppler, harmonic, deconvolution, non-
linear processing, frequency, special compound, and scan conversion with
interpolation are the most commonly used technologies.        The
applications become more and more important in the current trend of
ultrasound imaging systems. PC-based applications are adopted in current
commercial systems. They provide friendly user interface, easy-access
database, remote diagnostic, and data-storage for later analysis. Phased
array is widely used in the transducers of diagnostic ultrasound systems.
The beam-former diagnostic ultrasound part of the transmitter determines
the delay pattern and pulse train that set the desired transmit focal
point. The outputs of the beam-former are then amplified by high-voltage
transmit amplifiers that drive the transducers. These amplifiers may be
controlled digitally to shape the transmit pulses for better energy
delivery to the transducer diagnostic ultrasound part elements.
Typically, multiple transmit focal regions are used.      The field to be
imaged is divided up, by focusing the transmitted energy at progressively
deeper points in the body. The main reason for doing this is to increase
the transmitted energy to points that are deeper in the body, because the
signal becomes thinner and weaker as it travels into the body.        In
diagnostic ultrasound systems, the echo signal sampling is the start of
the back-end process. The acquired signals can be combined to extract the
useful part of the signal. Next, a user-controlled amplifier sets the
information signals amplitude, in order to achieve the best image.
The application block of the diagnostic ultrasound is designed to process
the basic information in various ways. It can, for example, generate 2D,
3D and 4D images, harmonic imaging (the second harmonic image has greater
clarity, contrast and detailing than the fundamental frequency range) and
color Doppler. It can also improve the image quality by filtering out
noise and artifacts.       Last, but not least, the scan conversion takes
the filtered data of the diagnostic ultrasound and puts it into a
presentable form for display. It converts the polar coordinates to
rectangular pixel positions. Normally this interpolation is done at the
same time during conversion. MedWOW medical Equipment offers medical
systems & parts for hospitals and clinics all around the world. To learn
more about Diagnostic Ultrasound Parts please visit our site medwow.com.
Related Articles - Diagnostic Ultrasound, Ultrasound, Ultrasound Scanner,
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posted:10/19/2011
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