Extraocular Muscles (extrinsic muscles) - move superior eyelid and eyball Flashcards
What are the Extraocular Muscles?
Superior Rectus, Medial Rectus, Lateral Rectus, Inferior Rectus, Superior Oblique, Inferior Oblique, Levator Palpebrae Superioris
What is the origin of the Superior Rectus muscle?
common tendinous ring
What is the insertion of the Superior Rectus muscle?
sclera of eyeball
What is the innervation of the Superior Rectus muscle?
CN III oculomotor nerve
What is the blood supply of the Superior Rectus muscle?
ophthalmic artery
What is the action of the Superior Rectus muscle?
rotate pupils superiorly and medially
What is the origin of the Medial Rectus muscle?
common tendinous ring
What is the insertion of the Medial Rectus muscle?
sclera of eyeball
What is the innervation of the Medial Rectus muscle?
CN III oculomotor nerve
What is the blood supply of the Medial Rectus muscle?
ophthalmic artery
What is the action of the Medial Rectus muscle?
rotate the pupils medially
What is noteworthy about the Medial Rectus muscle?
opposes Lateral Rectus muscle
What is the origin of the Lateral Rectus muscle?
common tendinous ring
What is the insertion of the Lateral Rectus muscle?
sclera of eyeball
What is the innervation of the Lateral Rectus muscle?
CN VI abducent nerve
What is the blood supply of the Lateral Rectus muscle?
ophthalmic artery
What is the action of the lateral rectus muscle?
rotate pupils laterally
What is noteworthy about the lateral rectus muscle?
loss of function will cause eye to be abducted
What is the origin of the Inferior Rectus muscle?
common tendinous ring
What is the insertion of the Inferior Rectus muscle?
sclera of eyeball
What is the innervation of the Inferior Rectus muscle?
CN III oculomotor nerve
What is the blood supply of the Inferior Rectus muscle?
ophthalmic artery
What is the action of the Inferior Rectus muscle?
rotate pupils inferiorly and medially
What is the origin of the Superior Oblique muscle?
apex of orbit above optic canal
What is the insertion of the Superior Oblique muscle?
sclera of eyeball
What is the innervation of the Superior Oblique muscle?
CN IV trochlear nerve
What is the blood supply of the Superior Oblique muscle?
ophthalmic artery
What is the action of the Superior Oblique muscle?
abducts, depresses and rotates pupils laterally
What is noteworthy about the Superior Oblique muscle?
passes through the trochlea (pulley)
What is the origin of the Inferior Oblique muscle?
floor of orbit lateral to lacrimal groove
What is the insertion of the Inferior Oblique muscle?
sclera of eyeball
What is the innervation of the Inferior Oblique muscle?
CN III oculomotor nerve
What is the blood supply of the Inferior Oblique muscle?
Ophthalmic artery
What is the action of the Inferior Oblique muscle?
abducts, elevates and rotates pupils laterally
What is the origin of the Levator Palpebrae Superioris muscle?
apex of orbit above optic canal
What is the insertion of the Levator Palpebrae Superioris muscle?
skin and fascia of upper eyelid
What is the innervation of the Levator Palpebrae Superioris muscle?
CN III oculomotor nerve
What is the blood supply of the Levator Palpebrae Superioris muscle?
ophthalmic artery
What is the action of the Levator Palpebrae Superioris muscle?
elevates superior eyelid