definitions
Last reviewed 01/2018
- ductions - all uniocular rotations
- vergences - all synchronous simultaneous movement of the eyes in opposite directions.
- versions - synchronous simultaneous movement of the two eyes in the same direction.
Versions can be:
- voluntary e.g. in response to commands, or,
- involuntary e.g. in response to stimuli (optical or auditory)
Examination of eye movements for supranuclear disorders must test these 3 modalities
- command saccades
- fixation saccades
- pursuit These three modalities may be affected together or separately in supranuclear eye movement disorders, and diagnosis often rests on this differentiation.