Levator palpebrae superioris muscle

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Levator muscle of upper eyelid
Eyemuscles.png
Rectus muscles:
2 = superior, 3 = inferior, 4 = medial, 5 = lateral
Oblique muscles: 6 = superior, 8 = inferior
Other muscle: 9 = levator palpebrae superioris
Other structures: 1 = Annulus of Zinn, 7 = Trochlea, 10 = Superior tarsus, 11 = Sclera, 12 = Optic nerve
Gray888.png
Sagittal section of right orbital cavity.
Latin Musculus levator palpebrae superioris
Gray's p.1021
Origin Sphenoid bone
Insertion Tarsal plate, upper eyelid
Artery Ophthalmic artery, superior ophthalmic vein
Nerve Oculomotor nerve
Actions Retracts / elevates eyelid
Antagonist Orbicularis oculi muscle
Anatomical terms of muscle

The levator palpebrae superioris (Latin for: elevating muscle of upper eyelid) is the muscle in the orbit that elevates the superior (upper) eyelid.

Structure

The levator palpebrae superioris originates on the lesser wing of the sphenoid bone, just above the optic foramen. It broadens and becomes the levator aponeurosis. This portion inserts on the skin of the upper eyelid, as well as the superior tarsal plate. It is a skeletal muscle. The superior tarsal muscle, a smooth muscle, is attached to the levator palpebrae superioris, and inserts on the superior tarsal plate as well.

Innervation

As with most of the muscles of the orbit, it is innervated by the superior division of the oculomotor nerve (Cranial Nerve III). This is why, when one turns one's eye upward, the eyelid tends to rise with it.1 An adjoining smooth muscle, the superior tarsal muscle, is sympathetically innervated and is occasionally considered to be part of the levator palpebrae superioris.

Function

The levator palpebrae superioris muscle elevates and retracts the upper eyelid.

Clinical signifiance

Damage to this muscle, or its innervation, can cause ptosis, the drooping of the eyelid. Ptosis can also be caused by damage to the adjoining superior tarsal muscle, or its sympathetic innervation. Such damage to the sympathetic supply occurs in Horner's syndrome, and presents as a partial ptosis.

Additional images

See also

This article uses anatomical terminology; for an overview, see anatomical terminology.

References

  1. ^ "eye, human."Encyclopædia Britannica. 2008. Encyclopædia Britannica 2006 Ultimate Reference Suite DVD 5 Apr. 2008

External links








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