Intermediate
Technical
IVT
duction
Pronunciation: DUK-shun
Monocular eye movement with the fellow eye covered or occluded.
Full Definition
Ductions are isolated movements of one eye while the other is covered, allowing assessment of individual extraocular muscle function without the influence of binocular reflexes. The six primary ductions correspond to the six cardinal directions of gaze: adduction, abduction, elevation, depression, and the oblique movements. Duction testing is particularly valuable in distinguishing between paralytic and restrictive causes of ocular motility limitation. Reduced ductions may indicate muscle weakness, nerve palsy, or mechanical restriction from orbital pathology.
Usage
Usage note: Always specify which eye and direction; distinguish from binocular version movements.
In Context
- "Forced duction testing confirmed mechanical restriction rather than muscle weakness as the cause of limited elevation." — Orbital fracture evaluation
- "Individual duction assessment revealed asymmetric abduction consistent with internuclear ophthalmoplegia." — Neurological motility examination
Also known as
monocular movement
Contrasted with
version
Don't confuse with
version
vergence