terminology
Last reviewed 01/2018
The terms used for description in the realm of squints include:
- binocular single vision - the ability to use both eyes to create a common perception
- orthophoria - perfect ocular balance in the binocular state
- porphoria - the eyes move out of the aligned state when they are dissociated - latent squint
- exophoria - the eyes diverge
- esophoria - the eyes converge
- hyperphoria - the visual axis of one eye moves vertically with respect to the other one
- manifest squint - if, in the binocular state, the eyes have different visual directions
- non-paralytic squint - the angle of the squint remains unaltered regardless of the direction of gaze
- paralytic squint - if the angle of non-alignment varies with a change in direction of gaze, the squint is incompetent and the causes is usually an infranuclear muscle palsy. This situation can also occur in a mechanical restriction of eye movement