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Simultaneous and Update Methods
Use of combination modes affects both the TI and MI through the combination of pulse types.
During simultaneous mode, the TI is additive. During auto-update and duplex, the TI will display
the dominant pulse type. The displayed MI will be from the mode with the largest peak pressure.
Sample Volume Depth
When Doppler sample volume depth is increased, the Doppler PRF may automatically decrease.
A decrease in PRF will decrease the TI. The system may also automatically decrease the pulse
voltage to remain below the system maximum. A decrease in pulse voltage will decrease the MI.
▐ Doppler, CW, M-Mode, and Color Imaging Controls
When a new imaging mode is selected, both the TI and the MI will change to default settings.
Each mode has a corresponding pulse repetition frequency and maximum intensity point. In
combined or simultaneous modes, the TI is the sum of the contribution from the modes enabled
and the MI is for the focal zone and mode with the largest derated intensity. If a mode is turned
off and then reselected, the system will return to the previously selected settings.
Probes
Each probe model available has unique specifications for contact area, beam shape, and center
frequency. Defaults are initialized when you select a probe. Factory defaults vary with probe,
application, and selected mode. Defaults have been chosen below the FDA limits for intended
use.
Depth
An increase in 2D-mode depth will automatically decrease the 2D-mode frame rate. This would
decrease the TI. The system may also automatically choose a deeper 2D-mode focal depth. A
change of focal depth may change the MI. The MI displayed is that of the zone with the largest
peak intensity.
Application
Acoustic output defaults are set when you select an application. Factory defaults vary with
probe, application, and mode. Defaults have been chosen below the FDA limits for intended
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