Eye Movement Flashcards
Action of the superior rectus? Innervation?
Elevates, rotates and adducts eyeball medially
(Inserts slightly medially to eye’s vertical axis of rotation)
Oculomotor nerve
Name the muscles of eye movement
Superior, inferior, lateral, medial rectus Superior oblique Inferior oblique
Action of the inferior rectus?
Innervation?
Depresses, adducts and rotates eyeball laterally
(Inserts slightly medially)
Oculomotor nerve
Action of the medial rectus?
Innervation?
Adducts eyeball
Oculomotor nerve
Action of the lateral rectus?
Innervation?
Abducts eyeball
Abducens nerve
Attachements and course of the superior oblique?
Originates from body of sphenoid bone. Tendon passes through trochlea, changes direction to go laterally, attaches to posterior surface of eye
What are the actions of the superior oblique?
Primary action: Intorsion (internal rotation)
Secondary action: Depression in adducted position (reading)
Tertiary action: Abduction
What does the superior oblique muscle do when acting alone?
Innervation?
Moves eye down and out
Trochlear
Attachments of the inferior oblique?
Originates from anterior part of the floor of the orbit and attaches deep to the lateral rectus, comes underneath the eye.
Actions of the inferior oblique?
Abducts, elevates and laterally rotates the eyeball
What is the equation for the innervation of the eye muscles?
LR6 SO4 R3
Innervation of the eye muscles?
Lateral rectus = CN VI - abducens nerve
Superior oblique = CN IV - trochlear nerve
All the rest = CN III - oculomotor nerve
What protects the cornea and eyeballs from injury, irritation and drying out?
Eyelids and lacrimal glands
Layers of the upper eyelid?
Skin
Areolar tissue
Fibres of orbicularis ori
Levator palpebrae superioris
Superior tarsus
Tarsal glands
Ciliary glands
Palpebral conjunctiva
What is the superior tarsus?
Dense connective tissue, a strengthening skeleton
Called the inferior tarsus on the lower lid
Superior tarsus muscle connects to it