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B–Mode
LOGIQ 500 Basic Users Manual
2276612–100 Rev. 0
5–12
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Controls (cont’d)
Depth B/M Gain
Description
Controls the distance over which the
B-Mode images anatomy. Display depth
may be changed according to the
anatomical size or to the region of interest.
Minimum/maximum values available
depend on the probe. Select from 4, 5, 6,
7, 8, 10, 12, 14, 16, 18, 20, 22, and 24 cm
for the desired depth.
Increases or decreases the amount of
echo information displayed in an image. It
has the effect of brightening or darkening
all displayed echoes at any depth.
Accessing/
Changing To reduce depth (look at a shallower
image), turn the Depth rotary encoder
clockwise.
To increase depth (look at a deeper
image), turn the Depth rotary encoder
counterclockwise.
NOTE: It is not possible to change the
gain on a frozen image.
Changing the gain while in another mode
does not affect the B-Mode image gain.
The Angle knob controls B-Mode gain in
B/M and CFM-B/M-Modes.
Benefits Depth adjusts the field of view. Increase
the field of view to look at larger or deeper
structures; decrease the field of view to
look at structures near the skin line. Allows for the balance of echo contrast so
that cystic structures appear echofree and
reflecting tissue fills in.
Values Depth increments vary by probe. Values
may be preset for each probe. Depth
displays on the monitor in centimeters. Gain displays on the monitor in dB. Gain
increments are available every 2 dB within
the range of 0 to 98 dB, depending on the
selected probe.
Affects on
Other Controls After adjusting the depth, it may be
necessary to adjust the TGC, focus, frame
rate and edge enhance.
Changing depth while scanning clears
Cine memory, but not Timeline Replay. A
bar is displayed in the timeline at which
point it is not possible to scroll past this
change.
After adjusting acoustic output, there may
be a need to adjust the gain. Generally
speaking, if acoustic output increases, the
gain may need to decrease; a decrease in
acoustic output may require an increase in
gain.
Gain and TGC interact together. Gain
changes overall echo amplification while
TGC changes amplification at specific
depths.
Bioeffects
Acoustic
Increasing the depth tends to decrease the
MI and TI because the frame rate slows
down. Gain has no affect on Acoustic Output.
However, with increased Gain, the output
level can usually be reduced to produce
equivalent image quality.
Acoustic
Output
Hazard
q g q y
Hints
Make sure enough space is left below the
anatomy of interest to demonstrate
shadowing or enhancement.