Duction
A duction is an eye movement involving only one eye.[1] There are generally six possible movements depending upon the eye's axis of rotation:
- Abduction refers to the outward movement of an eye.
- Adduction refers to the inward movement of an eye
- Supraduction / sursumduction / elevation
- Infraduction / deorsumduction / depression
- Incycloduction / intorsion
- Excycloduction / extorsion
Forced duction test
[edit]The forced duction test is performed in order to determine whether the absence of movement of the eye is due to a neurological disorder or a mechanical restriction.[2]
The anesthetized conjunctiva is grasped with forceps and an attempt is made to move the eyeball in the direction where the movement is restricted. If a mechanical restriction is present, it will not be possible to induce a passive movement of the eyeball.[3]
Notes
[edit]- ^ Kanski, JJ. Clinical Ophthalmology: A Systematic Approach. Boston:Butterworth-Heinemann;1989.
- ^ Forced duction - definition from Biology-Online.org
- ^ Kunimoto D, Kanitkar K & Makar M. The Wills Eye Manual. Office and Emergency Room Diagnosis and Treatment of Eye Disease. Fourth Edition. Lippincott Williams & Wilkins; 2004