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The extraocular muscles execute eye movements and are innervated by three cranial nerves. Contraction of the medial rectus pulls the eye towards the nose (adduction or medial movement). Contraction of the lateral rectus pulls the eye away from the nose (abduction or lateral movement).
In this manner, what does it mean to abduct the eye?
Strabismus is a position of the eyes where they are not directed at the same target (in some parts of the country this is termed a "squint"). Abduction is bringing the pupil away from the nose. Adduction is bringing the pupil toward the nose. Elevation is moving the pupil above the horizon.
| Muscle | Innervation | Primary action |
|---|---|---|
| Inferior rectus | Oculomotor nerve (inferior branch) | Depression |
| Superior oblique | Trochlear nerve | Incyclotorsion |
| Inferior oblique | Oculomotor nerve (inferior branch) | Excyclotorsion |
| Levator palpebrae superioris | Oculomotor nerve | Elevation/retraction of the upper eyelid |
In respect to this, what is Intorsion of the eye?
Eye Movements. Elevation and depression of the eye are termed sursumduction (supraduction) and deorsumduction (infraduction), respectively. Incycloduction (intorsion) is nasal rotation of the vertical meridian; excycloduction (extorsion) is temporal rotation of the vertical meridian. (See the image below.)
Secondary positions are up, down, right, and left gaze. These are achieved by pure rotations about the horizontal (x) or vertical (z) axes. Tertiary positions are oblique positions: up and right, up and left, down and right, and down and left [ 4 ].