FujiFilm VisualSonics Vevo MD, Руководство пользователя

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varying depth. Decisions that support prudent use are based on the type of patient,
exam type, patient history, ease or difficulty of obtaining diagnostically useful
information, and potential localized heating of the patient due to transducer surface
temperature. See
"Transducer surface temperature rise" on page 383. In the event of
a device malfunction, there are redundant controls that limit transducer power. This is
accomplished by an electrical design that limits both power supply current and voltage
to the transducer.
The sonographer uses the system controls to adjust image quality and limit ultrasound
output. The system controls are divided into three categories relative to output:
controls that directly affect output, controls that indirectly affect output, and receiver
controls.
Acoustic artifacts
An acoustic artifact is information, present or absent in an image, that does not
properly indicate the structure or flow being imaged. There are helpful artifacts that aid
in diagnosis and those that hinder proper interpretation. Examples of artifacts include
shadowing, through transmission, aliasing, reverberations, and comet tails.
For more information on detecting and interpreting acoustic artifacts, see the following
reference:
Kremkau, Frederick W. Sonography: Principles and Instruments. 8th ed., W.B.
Saunders Company, (2011).
Guidelines for reducing MI and TI
The following are general guidelines for reducing MI or TI. If multiple parameters are
given, the best results may be achieved by minimizing these parameters
simultaneously. In some modes changing these parameters does not affect MI or TI.
Changes to other parameters may also result in MI and TI reductions.
Please note the MI and TI values on the left side of the clinical display monitor under
Transmit .
Acoustic artifacts 379