The Orbit

What are the bones of the orbit?

1. Maxilla

2. Zygomatic

3. Frontal

4. Ethmoid

5. Lacrimal

6. Sphenoid

7. Palatine

What 2 structures pass through the optic canal?

The optic nerve (CN II) and ophthalmic artery

Why does the optic nerve pass through the optic canal?

To connect the eye to the brain

What structures pass through the superior orbital fissure?

Oculomotor nerve (CN III)

Trochlear nerve (IV)

Abducent nerve (VI)

Ophthalmic nerve (CN V1 = 1st branch of trigeminal nerve)

Superior ophthalmic vein

What structures pass through the inferior orbital fissure

Inferior ophthalmic vein

What does the levator palpebrae superioris do?

raises eyelid

What does the superior rectus do?

Elevates and adducts the eye

What does the inferior rectus do?

Depresses and adducts the eye

What does the medial rectus do?

Adducts

What does the lateral rectus do?

Abducts

What does the superior oblique do?

Depresses and abducts the eye

What does the inInferior oblique do?

Elevates and abducts the eye

Where does most of the blood supply in the face come from?

external carotid artery

What artery does the ophthalmic artery branch from?

internal carotid artery

What are the orbital branches of the ophthalmic artery

Lacrimal

Muscular

Supra-orbital

Anterior ethmoidal

Posterior ethmoidal

Medial palpebral

Supratrochlear

Dorsal nasal

What does the lacrimal branch supply?

glands and lateral eye lids

What does the muscular branch supply?

extraoccular muscles of the eye

What does the supra-orbital branch supply?

forehead

What dose the Anterior ethmoidal branch supply

Nasal septum

What does the posterior ethmoidal branch supply?

sinuses

What does the medial palpebral branch supply?

Eyelids

What does the supratrochlear branch supply?

forehead and scalp

What does the dorsal nasal branch supply?

Upper nose

Where is the area that the ocular branches go?

structures within the eye

What provides blood supply to inside the eyeball?

Posterior ciliary

What are the two ocular branches?

Central retinal and posterior ciliary

What are the muscles innervated by the Occulomotor nerve (CN III)

1. Levator palpebrae superioris

2. Superior rectus

3. Inferior rectus

4. Medial rectus

5. Inferior oblique

What innervates the lateral rectus?

Abducens CN VI

What innervates the superior oblique?

Trochlear CN IV