Mindray Ana, Operator'S Manual

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H Acoustic Output
Operator’s Manual H - 3
Although the output power is automatically controlled for the selected applications, high TI values
should be kept to a minimum or avoided in obstetric applications. WFUMB (World Federation for
Ultrasound in Medicine and Biology) guidelines: state that temperature increase of 4 degree C for 5
min or more should be considered as potentially hazardous to embryonic and fetal tissue.
The smaller the MI/TI values, the lower the bioeffects.
H.4.2 MI/TI Display
TI and MI values are displayed in the upper 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 needed for effective diagnosis.
NOTE:
If there is a value of MI or TI exceeds 1.0, you must be careful to practice the ALARA
principle.
The display precision is 0.1.
Real-time Display accuracy: MI
≤ 28.5%, TI ≤ 38.7%
H.5 Acoustic Power Setting
Acoustic power adjustment
Use the [A.power] to adjust the acoustic power percentage, and 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 setting of acoustic power
Selection of diagnostic applications is the most important factor for 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.
In this system, imaging setups can be created using the ultrasound output set by you.
Once you perform preset settings, default setting values of the system may be changed and invalid.
It is the user’s responsibility for any change to the default settings.
Adjusting range
Initial power: 0.13% 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 acoustic power value refer to the best image quality of the probe. The larger the
acoustic power value, the better the image quality.
93.33
NOTE:
This system automatically returns to the settings whenever changes are made to the values
(when you turn on the power, switch between probes, end the exam, or select OK or Cancel in
the Setup menu). In the factory default settings, the Acoustic Output is limited below 100%.