Levator palpebrae superioris muscle

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Levator muscle of upper eyelid

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

Sagittal section of right orbital cavity.
Latin	musculus levator palpebrae superioris
Gray's	subject #227 1021
Origin:	sphenoid bone
Insertion:	tarsal plate, upper eyelid
Artery:	ophthalmic artery, superior ophthalmic vein
Nerve:	oculomotor nerve
Action:	retracts//elevates eyelid
Antagonist:	orbicularis oculi muscle
Dorlands/Elsevier	m_22/12549616

The levator palpebrae superioris (or levator muscle of upper eyelid) is the muscle in the orbit that elevates the superior (upper) eyelid.

1 Structure
2 Innervation
3 Actions
4 Pathology
5 Additional images
6 See also
7 External links

[edit] Structure

The levator palpebrae superioris originates on the lesser wing of the sphenoid bone, just above the optic foramen. It 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.

[edit] Innervation

As with most of the muscles of the orbit, it is innervated by the superior division of the oculomotor nerve (Cranial Nerve III). An adjoining smooth muscle, the superior tarsal muscle, is sympathetically innervated and is occasionally considered to be part of the levator palpebrae superioris.

[edit] Actions

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

[edit] Pathology

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.

[edit] Additional images

The sinuses at the base of the skull.	Nerves of the orbit. Seen from above.	Dissection showing origins of right ocular muscles, and nerves entering by the superior orbital fissure.	The right eye in sagittal section, showing the fascia bulbi (semidiagrammatic).
Sagittal section through the upper eyelid.