Gilras GRU-5000 A, Руководство по эксплуатации

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Chapter 4 Operation
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selection, then the input or selected acoustic velocity will disappear. Click OK key to save the set
acoustic velocity; or click CANCEL key to exit (no parameter in this mode will be saved).
The Default Acoustic Velocity set is shown below:
Unit: m/s
IOL PMMA ACRYLIC SILICONE CATARACT
Acoustic Velocity (m/s) 2718 1946 1050 1629
4.3.2.3 Measurement under AUTO Mode
1) CONTACT Method
Switching on the instrument will enter AUTO mode automatically, or select AUTO mode according
to the description of
Mode Selection
in section §4.3.2.2a, the default measuring method is
CONTACT, and the operation procedure is as follows ：
a) Let the patient lie down, open his/her eye to perform surface anesthesia.
b) Step onto the foot switch or click SCAN/FREEZE key to start measuring.
c) Place the probe gently onto the patient's cornea vertex, and tell the patient to look at the probe
straightly.
d) Generally, it is not necessary to adjust the gain and threshold. For some special cases (e.g.
severe cataract patients), low retina reflective amplitude or poor waveform maybe appear, adjust
the gain or threshold then to get the clear reflective waveform of the tissue interface, sharp front
edge is preferred.
e) When the probe is properly aligned, you will hear a series of beep sounds, the waveform is
automatically frozen and data will be displayed on the screen. The GRU-5000A supports
displaying up to eight groups of data, and there will be a long beep sound after all eight groups of
data are acquired. The instrument will stop measuring automatically after the data displays on the
screen, and the probe can be removed then. The average value of each group and standard
deviation display on the upper side of the waveform display area.
f) If the data are not acquired, please move the probe slightly until getting the measurement. Keep
the probe stably in the position found, eight groups of data will be acquired.
g) If the standard deviation is big, it may caused by the moving of probe during measurement.
Move the cursor with keys and observe each group of data and its corresponding
waveform. Click MARK key to mark unreliable data, click again to cancel the mark. The marked
data will not be calculated. Or click DEL key to delete the inaccurate data.
Note: 1) The deleted data will not be calculated and are unrecoverable, so please
operate cautiously.
2) Since the results of each automatic measurement will subject to multiple
sampling averages, the operator is required to perform the scanning gently