Virtual Touch Applications; Acoustic Radiation Force Impulse Technology - Siemens Acuson S1000 Instructions For Use Manual

Acoustic Radiation Force Impulse Technology

WARNING: To prevent the possibility of inadvertently heating tissue, avoid repeated image
acquisitions near the interface of bone and tissue within a short period of time.
The following features use acoustic radiation force impulse (ARFI) technology to obtain
qualitative visualizations or quantitative measurements of tissue stiffness:
Virtual Touch Imaging

Virtual Touch Quantification

Virtual Touch IQ

ARFI technology uses a time-controlled sequence of "push pulses" from the transducer, rather
than manual compression or palpation cycles, to induce a small displacement of tissue. The
image qualitatively depicts the relative stiffness of tissue within a selected region of interest
compared to surrounding tissue. The system can also provide a quantitative measurement of
shear velocity (Vs) or elasticity (E) at a specific anatomical location.
During acquisition, ARFI technology combines a period of pulse sequences with a temporary
freeze period of no transmit power. A timer indicates the remaining time in seconds until the
transducer is available for imaging. This duration is typically a few seconds depending on the
transducer and imaging conditions. The cooling timer prevents possible heating of the
transducer surface from the momentary shear wave generation pulses.
Cooling 5
Example of Virtual Touch timer.
The system uses an optimization algorithm to ensure acceptable levels for the I
Mechanical Index (MI), and the Thermal Index (TI) during use. When imaging is activated, you
cannot adjust imaging parameters that affect the transmit power output until the acquisition is
complete.
I n s t r u c t i o n s f o r U s e
1 0 V i r t u a l T o u c h A p p l i c a t i o n s
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