Heterophoria Apparent squint

1. • Clinical impression of ocular deviation, when no squint is present

2. In high myopia, the fovea lies NASAL to the optic axis. So, the visual axis
crosses temporal to the optic axis at the cornea. (-ve angle alpha)

3. In high hyperopia, the fovea lies more Temporal to the optic axis than normal.
So, the visual axis crosses nasal to the optic axis at the cornea. (large +ve
angle alpha, > 5 degrees)

4. • Tendency of the eye to deviate when fusion is blocked ‫ميول‬‫انحرافية‬😂
A. Uncorrected error of refraction
B. EOM imbalance
• Exophoria ‫خفي‬ ‫وحشي‬ ‫انحراف‬
• Esophoria ‫خفي‬ ‫أنسي‬ ‫انحراف‬
1. Esophoria
2. Exophoria
3. Hyperphoria
4. Hypophoria
5. Incyclophoria
6. Excyclophoria

5. • Nothing
• Blurred vision
• Running letters
• Ocular strain
• e.g. at time of stress
or poor health

6. • The Maddox rod consists
of a series of fused
cylindrical red glass rods
that convert the
appearance of a white
spot of light into a red
streak
• Exophoria
• Esophoria
• Orthophoria

7. • The Maddox wing dissociates the eyes for near
fixation (1/3 m) and measures heterophoria.
• The instrument is constructed in such a way
that the right eye sees only a white vertical
arrow and a red horizontal arrow, whereas the
left eye sees only horizontal and vertical rows
of numbers.

8. • Pencil to nose exercise

9. • e.g. base-out prism
to exercise
exophoria

10. • The instrument consists of two cylindrical tubes
• Pictures are inserted in a slide carrier situated at the outer end of each tube

11. • for large deviations
• e.g. base in prism to relieve
exophoria