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
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Sagittal section of right orbital cavity.
Details
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
Identifiers
Latin Musculus levator palpebrae superioris
Dorlands
/Elsevier
m_22/12549616
TA A15.2.07.020
FMA 49041
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[edit]

The levator palpebrae superioris originates on the lesser wing of the sphenoid bone, just above the optic foramen. It broadens and decreases in thickness (becomes thinner) 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[edit]

As with most of the muscles of the orbit, the levator palpebrae receives somatic motor input from the ipsilateral superior division of the oculomotor nerve (Cranial Nerve III). An adjoining smooth muscle, the superior tarsal muscle, which is occasionally confused to be a portion of the levator palpebrae superioris, is actually only attached, and it is separately innervated by sympathetic fibers that originate in the cervical spinal cord.

Function[edit]

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

Clinical signifiance[edit]

Damage to this muscle or its innervation can cause ptosis, which is drooping of the eyelid. Lesions in CN III can cause ptosis because without stimulation from the oculomotor nerve, the levator palpebrae cannot oppose the force of gravity, and the eyelid droops.

Ptosis can also result from 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. It is important to distinguish between these two very different causes of ptosis. This can usually be done clinically without issue, as each type of ptosis is accompanied by other distinct clinical findings.

Additional images[edit]

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