Cross Cylinder; Examination For Astigmatism - Ametek Reichert Phoroptor VRx User Manual

Performing an Exam

Cross Cylinder

1. Tap XCyl in the menu bar at the bottom of the main screen, or Press both the C and A buttons to
activate the Cross Cylinder function.
2. If the XCyl Mode setting is set to "User Select," three test options display: Manual, Smart, or Split Cyl.
• Manual - Refines Axis in 1°, 5°, or 10° increments, and adjust Cylinder in ±0.25 D, ±0.50 D, or
±1.00 D increments.
• Smart - Automatically brackets Axis and Cylinder based on patient response.
• Split Cyl- Use a Split Cyl lens to present two targets simultaneously to refine Axis and Cylinder.

Examination for Astigmatism

If the Cross Cylinder Mode (XCyl) is activated and the current Cylinder value is zero, an Astigmatism
check will automatically start, and a 0.50 D JCC lens will be placed in the Phoroptor head.
1. Turn the CONTROL KNOB to present the Cross Cylinder target at 0° and 90°.
2. Ask the patient "which is better, 1 or 2?"
If the patient states a preference, turn the CONTROL KNOB to that number and press the knob,
•
or tap 1 or 2 on the screen.
• If the patient does not see a difference between the two charts, press the ENTER button or tap
Equal on the screen.
3. Ask the patient to compare two charts at 45° and 135°.
If the patient states the charts are equal, no astigmatic correction is needed. Press the ENTER
•
button or tap Equal on the screen.
• If the patient has a preference, turn the CONTROL KNOB to that number and press the knob, or
tap 1 or 2 on the screen.
4. If any patient preference was indicated, the test automatically advances to axis adjustment for the
XCyl test that was selected.
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