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A step-by-step procedure to check for proper function of the necessary parts of the device.


NOTE: A credit card and a drop of water or saline is required for this test. 


  1. Place a drop of water or saline on a credit card.
  2. Press the ON button (unit will defer to RK mode).
  3. Press the READ button (CAL will display).
  4. Gently depress the probe tip on the credit card through the water droplet. Hold the probe perpendicular to the credit card.
  5. Readings will continuously be displayed as long as contact and orientation is maintained. Three beeps will be heard each time a reading is taken.
  6. Remove the probe from the water drop , dry the clear tip with a tissue, wipe down the entire hand piece and tip with alcohol, air-dry, and replace protective white rubber tip and return.
  7. Press the PRINT button for the printout.
  8. When the printout is completed, press the RESET button.
  9. Press the MODE button until ‘OFF’ displays.
  10. Press the ENTER button to switch the device off.

The Corneo-Gage Plus housing should be cleaned periodically with a slightly detergent dampened cloth.


The probe and cord should be routinely cleaned and disinfected with alcohol, Pantasept, Cidex or an equivalent antiseptic agent.


PRECAUTION: Never use solvents such as acetone, thinner, benzine or abrasive cleaners on the housing and probe tip as these will damage the device.

PRECAUTION: Do not soak the probe in saline solution, alcohol, or hydrogen peroxide as these will damage the device.



  1. Remove printer cover as in Fig 1 & 2.
  2. Remove the spindle and empty paper spool form printer. Discard the paper spool.
  3. Slide the spindle through the spool of the new roll (Fig 3)
  4. Orient the roll of paper so that the paper feeds from under the roll and towards the front of the instrument (Fig. 4). Mount the spindle with the paper roll into the printer by inserting the mounting tips (located at each end of the spindle (Figs 5 & 6)
  5. Insert the end of the paper through the horizontal slot located under the printer cartridge (Fig. 7).
  6. Press the ON key.
  7. Press the mode key repeatedly until ‘PF’ is displayed. Then press the = key to advance the paper until approximately 2-3 inches emerges from the exit slot (Figs. 8 & 9)
  8. Thread the paper through the bottom of the printer cover/cutter slot (Fig. 10)
  9. Replace the printer cover (Fig. 10)


Misalignment Error

If the probe is not absolutely perpendicular to the cornea, an error of increased thickness will result. Corneo-Gage Plus allows only a 5 degree angulation margin to permit the best measurements IF you are not within this margin, you will not get readings.

Wet Probe Error

If the probe tip is wet, a false reading of the water (tear) droplet may occur before the cornea is indented and upon removal.