A duction is an
eye movement involving only one
eye
Eyes are organs of the visual system. They provide living organisms with vision, the ability to receive and process visual detail, as well as enabling several photo response functions that are independent of vision. Eyes detect light and conv ...
. There are generally six possible movements depending upon the eye's
axis of rotation:
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Abduction
Abduction may refer to:
Media
Film and television
* "Abduction" (''The Outer Limits''), a 2001 television episode
* " Abduction" (''Death Note'') a Japanese animation television series
* " Abductions" (''Totally Spies!''), a 2002 episode of an ...
refers to the outward movement of an eye.
#
Adduction refers to the inward movement of an eye
#Supraduction / sursumduction / elevation
#Infraduction / deosumduction / depression
#Incycloduction / intorsion
#Excycloduction / extorsion
Forced duction test
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.
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.
[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]
Notes
{{Reflist
See also
*
Extraocular muscles
*
Eye examination
An eye examination is a series of tests performed to assess vision and ability to focus on and discern objects. It also includes other tests and examinations pertaining to the eyes. Eye examinations are primarily performed by an optometrist, ...
*
Vergence
A vergence is the simultaneous movement of both eyes in opposite directions to obtain or maintain single binocular vision.
When a creature with binocular vision looks at an object, the eyes must rotate around a vertical axis so that the projec ...
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Version (eye)
Eye
Ophthalmology