© MEDISTIM 2015
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5.10 Other adjustments
For adjustments such as setting the time and date, name of
surgeons, editing the vessel names, deselecting automatic
vessel pop-up and adjusting the number of thumbnails visible
in the “Archive” screen.
There are two system modes: advanced and clinical. The
advanced mode contains options such as derived curves and
trend recordings. The clinical mode is tailored for common
cardiac and vascular surgeries, and only the most frequently
used options are available. The advanced and clinical user
modes are activated in the system settings menu.
5.11.1 Advanced Doppler mode
If the probe controls are not visible in the Doppler display
there are two options:
1.
Press the button reading “DP V 45°” and adjust the
settings in the screen that appears.
2.
Press the button reading “DP V 45°”, select “Show
Probe Controls in Curve View” and adjust the gain in
the Doppler display. The selection will be active until
it is de-selected.
Optimizing display gain
When the Doppler spectrum appears faint or saturated, the
gain can be adjusted.
1.
Press the ”+”button (1) in the lower right part of the
Doppler display to increase the gain if the spectrum
appears faint.
2. Press the ”-”button (2) in the lower right part of Dop-
pler display to decrease the gain if the spectrum
appears noisy.
Change of sample volume
By default the system measures all velocities at depths
between 2 mm and 8 mm. The field of measurement and the
sample volume can be changed.
To change sample volume
1.
Press the ”+”button (3) in the Doppler display to in
-
crease the sample volume
2. Press the ”-” button (4) in the Doppler display to de-
crease the sample volume.
3. To increase or decrease depth, press the top or bot-
tom of the scale respectively.
As shown in the figure above, the number on the right indi
-
cates the depth of the measurement in mm and the number
on the left indicates the sample volume in mm.
Note
The depth is measured from the probe surface, and indicates
the real depth to the center of the sample volume. However,
since the beam is transmitted at a 45º angle, the actual mea-
sured sample is situated in front or behind the probe depend-
ing on probe direction.
Change the filter settings
Probe movements may introduce noise close to the baseline,
especially when measuring on a beating heart. Increasing the
filter setting can reduce the amount of noise. Press the ”DP
V 45º” button and select a higher filter value under ”HP Filter
Frequency”. The factory default is 100hz.
5.10.1 Tuning Doppler noise
The Doppler measurement is sensitive to noise from the
instruments nearby, possibly causing the calculated val-
ues from the measurement to be inaccurate. Therefore this
calibration should be done in an environment resembling
the working environment of the VeriQ™ in question. For the
purpose of tuning of the noise reduction, the probe can be
placed in a cup of water.
