Eye Movements Flashcards
Why do we have binocular vision?
Wider field of vision,
Depth perception,
Element of redundancy (though not really).
what does misalignment of visual axes cause?
Diplopia (double vision?)
where do the 6 muscles that move the eyeball insert?
The sclera
Where do the extra ocular muscles originate from?
Apex of the orbit, apart from inferior oblique which arises from the floor of the orbital cavity anteriorly.
What is the common origin of the 4 recti?
Common tendinous ring
What does the pneumonic LR6SO4 signify?
Lateral rectus is supplied by cranial nerve VI,
Superior oblique is supplied by cranial nerve IV.
Why do some muscles end up attaching to the eye at an oblique angle?
Extraocular muscles run in line with the axis of the orbit, which runs at an oblique angle to the visual axis of the eye.
How is primary resting gaze maintained?
Antagonism of muscles provides equal and opposite pull. Without this, deviation occurs.
What movements is the eye capable of?
Elevation, depression, abduction, adduction, intorsion, extorsion.
What movement is caused by the medial rectus?
What about the lateral rectus?
Adduction.
Abduction.
What movements are completed by the superior rectus?
Elevation (most powerful when eyes are lateral) slight adduction, slight intorsion.
Where does the superior rectus originate?
How does it insert?
Arises from the apex of the orbit.
Inserts obliquely into superior anterolateral surface of the globe.
What actions is the inferior rectus responsible for?
Depression (stronger if eyes lateral), adduction, extorsion.
Where does the inferior rectus muscle originate?
How does it insert?
Originates at the apex of the orbit.
Inserts obliquely into anteroinferior surface of the globe.
What movements is the superior oblique responsible for?
Intorsion, depression (stronger when eye medial), slight abduction
