Subjective Cover Test

Diplopia: ESOs

- ESOs have uncrosses or homonymous diplopia - the OD image is seen to the patient's right, and the OS image is seen to the patient's left

Subjective Cover Test: Eso

the patient see the object moving in the OPPOSITE direction as the paddle

Subjective Cover Test: Exo

the patient sees the object moving in the SAME direction as the paddle

When should you perform subjective cover test?

when the movement of the eyes is so small that no motion is seen or motion is questionable

Diplopia: EXOs

- EXOs have crossed or heteronymous diplopia - the OD image is seen to the patient's left, and the OS image is seen to the patient's right (think about where light hits the retina)

Why might a patient have diplopia?

1. phoric deman and not enough fusional vergence to keep fusion (intermittent tropia) 2. They have a tropia - if the tropia is recent onset, they will probably report diplopia - if the tropia is long standing, the patient will likely be suppressing and will not have diplopia