Chison SonoEye P3, Руководство пользователя

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Digital Color Doppler Palm Ultrasound System
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Pr’ is the de-rated (0.3) peak rare-fractional pressure in Mpa at the point where PII is the maximum, and
fc is the center frequency in MHz. PII is the Pulse Intensity Integral that the total energy per unit area carried
by the wave during the time duration of the pulse. The peak rare- fractional pressure is measured in
hydrophone maximum negative voltage normalized by the hydrophone calibration parameter.
Display Guideline:
For different operation modes, different indices must be displayed. However, only one index needs to be
shown at a time. Display is not required if maximum MI is less than 1.0 for any setting of the operating mode,
or if maximum TI is less than 1.0 for any setting of the operating mode. For TI, if the TIS and TIB are both
greater than 1.0, the scanners need not be capable of displaying both indices simultaneously. If the index
falls below 0.4, no display is needed.
Display and Report in Different Mode
Located on the upper middle section of the system display monitor, the acoustic output display provides the
operator with real-time indication of acoustic levels being generated by the system.
Only display and report TIS or TIB and start from 0.4 if maximum TI > 1.0, display in increments of 0.2 for
values of indices of 2.0 or less, and 0.5 for values of indices greater than 2.0.
Below is a simple guideline for the user when TI exceeds one limit exposure time to 4(6-TI) minutes based
on the ‘National Council on Radiation Protection. Exposure Criteria for Medical Diagnostic Ultrasound: I.
Criteria Based on Thermal Mechanisms. Report No.113 1992’.
Operator Control Features:
The user should be aware that certain operator controls may affect the acoustic output. It is recommended
to use the default (or lowest) output power setting and compensate using Gain control to acquire an image.
Other than the output power setting in the soft-menu, which has the most direct impact on the power; the
PRF, image sector size, frame rate, depth, and focal position also slightly affect the output power. The
default setting is normally around 70% of the allowable power depending on the exam application mode.
Controls Affecting Acoustic Output
The potential for producing mechanical bioeffects (MI) or thermal bioeffects (TI) can be influnced by certain
controls.
Direct: The Acoustic Output control has the most significant effect on Acoustic Output.
Indirect: Indirect effects may occur when adjusting controls. Controls that can influence MI and TI are
detailed under the Bioeffects portion of each control in the Optimizing the Image chapter.
Always observe the Acoustic Output display for possible effects.
Best practices while scanning
HINTS:
Raise the Acoustic Output only after attempting image optimization with controls that have no
effect on Acoustic Output, such as Gain and STC.