CLINICAL OPTOMETRY III PROBLEM SET

Assume a 40 cm working distance.

1. A patient with a 60 mm PD has a distance phoria of 2 exo and a near phoria of 3 eso. Assuming no proximal convergence, calculate the AC/A ratio.

2. The above patient has a - 1.00 gradient near point phoria of 5 eso. Calculate the PC/A ratio.

3. The above patient has a PRC of x/ 12/3 and an NRC of 6/10/-3. Calculate the amount of prism correction necessary to meet Sheard's criterion for visual comfort.

4. Calculate the magnitude of the above patient's PFC and NFC ranges.

5. The PRC is re-tested while the above patient is looking through a total of 5pd BO prism. Calculate the repeated PRC value.

6. Another patient with a 60 mm PD has a distance phoria of 2 exo. If the AC/A ratio is 3/1 and the PC/A ratio is 2/1, calculate the near point phoria.