30
USER MANUAL RETEVET™ PORTABLE ERG
T +49 7461 96 580 0 | F +49 7461 96 580 90 | export@eickemeyer.com | www.eickemeyer.com
8. TROUBLESHOOTING HINTS
The RETevet™ device runs internal tests and self-checks frequently. Device failures are obvious; the device will stop functioning
and warn the user rather than producing erroneous or unexpected results.
If the device displays an error message, follow the instructions on the screen to remediate the error, or contact the
EICKEMEYER® customer service. Note any error number shown in your email message.
Charge the Battery when the Charge is low
When the RETevet™ device battery charge is low, a warning message is shown on the device screen. Return the device to the
docking station and let it charge. Do not try to test a patient after seeing this message.
A full charge permits testing of approximately 70 patients, depending on the protocol used. The device takes approximately
4 hours to charge completely.
The battery’s state of charge can be seen on most screens via the battery icon in the upper right corner. The amount of green
in the icon represents the remaining capacity.
Measure the Patient’s Right Eye First
The RETevet™ device is designed to measure the patient’s right eye fi rst. If you only want to measure a patient’s left eye, use
the skip button to proceed past the right eye screen without testing the patient. The default is to test both eyes. Using the
skip button you can test only the right eye or only the left eye.
The Device doesn’t Show the Next Button after I connect the Electrode or after pressing the Start Test Button, I get an “The
Electrodes have been disconnected” Error
The RETevet™ device monitors the electrical impedance of the connection between the electrodes. If the impedance is too
high, the Next button won’t be displayed. During a test, if the electrical impedance gets too high or the inputs saturate the
analog to digital converter, the “electrodes disconnected” message is displayed. The impedance and / or electrode noise can
be too high because of the following reasons:
1. 3-plug lead is not correctly connected to the electrodes. Check the connection and try reconnecting the lead. Don’t pull on
wires as the connection can break at either end without being visible.
2. The electrodes are poorly connected to the patient. Ensure the active electrode is well placed on the cornea and secured
with viscous solution (typically hydroxypropyl methylcellulose 2.5), and both, reference and ground electrodes are inserted
all the way in.
3. Any of the electrodes may be defective, try another electrode when in doubt.
The Device Shows “Excessive electrode noise”
The RETevet™ device monitors the electrical noise of the connection between electrodes. The electrode noise (including
power-line interference) is found by computing 2√2 times the standard deviation of the electrical response in the bandwidth
48 – 186 Hz to robustly estimate the peak-to-peak noise. If the electrode noise exceeds 5,600 µV for fl icker tests, the noise
level is displayed. It is recommended that you try to reduce the noise before pressing the Next button to ensure quality
recordings. The noise may be high for the following reasons:
1. The patient may be generating excessive electromyogram noise by moving or not being deeply anesthetized.
2. The impedance of the electrodes is too high. Check the placement of the corneal electrode, add gonioscopic solution, make
sure needles are fully inserted and were not bend, change electrodes if nothing else works.
To Next Page
Loading...
Need help?
General