Mindray DC-80A, Руководство оператора

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Acoustic Output 15-3
15.4.2 MI/TI Display
TI and MI values are displayed in the top part of the screen in real time. The operator should
monitor these index values during examinations and ensure that exposure time and output values
are maintained at the minimum amounts required for effective diagnosis.
NOTE: If a value of MI or TI exceeds 1.0, the ALARA principle must be practiced.
The display precision is 0.1.
Display accuracy of MI is
≤
14.7%, and TI is
≤
28.5%.
15.5 Acoustic Power Setting

Acoustic power adjustment
Click the [A.power] on the soft menu to adjust the acoustic power percentage. Its value is
displayed on the corresponding item, as well as at the top of the screen. The greater the
acoustic power percentage, the greater the current acoustic output. When the image is frozen,
the system stops transmitting acoustic power.

Default acoustic power setting
Selection of diagnostic applications is the most important factor in controlling ultrasound output.
The permissible level of intensity of ultrasound differs depending on the region of interest. For
fetal examinations, in particular, much care must be exercised.
Within this system, imaging setups can be created using the ultrasound output set by you.
Once you set the preset settings, the system's default setting values may be changed
and invalid. The user is responsible for any change to the default settings.

Adjusting range
Initial power: 3.2% to 100%*
Definition of 100%: the maximum acoustic power of a probe determined by the increase in
probe surface temperature in the selected mode and the acoustic power restrictions specified
by the FDA.
Default settings of the acoustic power value refer to the best image quality for the probe. The
larger the acoustic power value, the better the image quality.
In the DC-80A series product, to obtain optimum images for applications under the
requirements of safety and ALARA principle, we set acoustic power default values in factory to
be maximum 96.6% in all exam modes for a better image quality. The user can make
adjustments according to the imaging effect in practical use.
NOTE: This system automatically returns to the settings whenever changes are made to the
values (when you turn on the power, switch between probes, press <End Exam>, or
select OK or Cancel in the Setup menu). In the factory default settings, the Acoustic
Output is limited to below 100%. Following the ALARA restriction, you are allowed to
increase the acoustic power under FDA 510(k) Guidance-Track 3 limits and to set it in
the image preset screen.
The system's acoustic output has been measured and calculated in accordance with
IEC60601-2-37: 2015, FDA 510(K) GUIDANCE, IEC 62359, Ultrasonics-Field
characterization-Test methods for the deter mination of thermal and mechanical indices related
to medical diagnostic ultrasonic fields, 2017 and Medical electrical equipment-Part 2-37:
Particular requirements for the basic safety and essential performance of ultrasonic medical
diagnostic and monitoring equipment issued by IEC in 2015.