Ametek Reichert Phoroptor VRx User Manual page 82

Instructions for Use
Prism Testing
(continued)
Horizontal Phorias Test
1. Select an appropriate test chart of a single vertical line of optotypes or a single optotype.
(Please refer to Figure IU-27.)
2. Verify that the patient can see two images, one up and one down.
3. Enter BO Prism or add more BI Prism, if the patient cannot see two targets.
4. Enter BO Prism, until the two images align, like buttons on a shirt.
5. Press the CONTROL KNOB, or touch ALIGNED.
Note: The magnitude of lateral Phoria is the power of the Prism when the images are aligned.
Note: The power of horizontal Phoria appears in the dialog box in the section labeled "H".
Vertical Phorias Test
After the horizontal phoria is determined, the Prism power is restored to 10 BI Prism in the left eye, as a
starting value for the vertical phoria test. (Please refer to Figure IU-28.)
1. Select an appropriate test chart of a single horizontal line of optotypes or a single optotype.
2. Verify that the patient can see two images.
3. Enter BU Prism until the two images align horizontally, like headlights on a car to measure the
vertical phoria.
4. Press the CONTROL KNOB, or touch ALIGNED.
Note: The magnitude of the vertical Phoria is the power of the Prism when the images are
aligned.
Note: The power of the vertical Phoria appears in the dialog box in the section labeled "V".
82
(continued)
Figure IU-28, Vertical Phoria Test Screen
16241-101 Rev. D