GE Vivid 7, Руководство по обслуживанию

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GE H
EALTHCARE
D
IRECTION
FC091194, R
EVISION
11 V
IVID
7 S
ERVICE
M
ANUAL
4 - 48 Section 4-3 - Functional Checks
4-3-8-8 Check Frequency, Radial Averaging, Lateral Averaging, Power
4-3-8-9 Adjust ROI
Table 4-17 Color-Mode Soft Menu Controls Check
Step Task Expected Result(s)
1. Adjust Frequency
Enables the adjustment of the transmission frequency to
control the sensitivity or the level of penetration.
The selected frequency is displayed in the status
window.
Adjusting Frequency may affect Sample Volume and
LVR settings.
2. Adjust Radial Averaging
Smooths the image by averaging collected data along
the same radial line.
An increase of the radial averaging will reduce noise, but
this will also reduce the radial resolution.
3. Adjust Lateral Averaging (Color 2D only)
Smooths the image by averaging collected data along
the same horizontal line.
An increase of the lateral averaging will reduce noise,
but this will also reduce the lateral resolution.
4. Adjust Power
Controls the amount of acoustic power applied in all
modes.
When power is set to maximum, it is equal to or less than
the maximum acoustic power permitted by the FDA.
The Thermal Index (TI) and the Mechanical Index (MI)
are displayed on the screen.
Table 4-18 Adjust ROI
Step Task Expected Result(s)
1. Adjust Sample volume
Adjusts the size of the color flow Doppler sampling area.
Lower setting gives better flow resolution while a higher
setting increases sensitivity and helps to locate
disturbed flows.