Session 8: Extra-Ocular Eye Muscles And Their Actions Flashcards
What cranial nerves supply muscles that move the eyeball?
CN III, CN IV and CN VI
Which division of the nervous system are the intrinsic muscles of the eye innervated by?
Autonomic
What type of nerves supply the extra-ocular muscles?
Somatic motor nerves
Where on the eye do the extra ocular muscles attach?
The sclera
Which two extra-ocular muscles are not innervated by CN III?
Lateral rectus and superior oblique
What muscles move the eyes directly upwards?
Superior rectus and inferior oblique
What muscles move the eyes directly downwards?
Superior oblique and inferior rectus
What is the action of the superior oblique muscle?
Moves the eyeball down and out and intorts the eyeball
What is the action of the inferior oblique muscle?
Rolls the eye up and out and extorts the eyeball
What is the action of the superior rectus muscle?
Rolls the eye up and in
What is the action of the inferior rectus muscle?
Rolls the eye down and in
How do you examine the eye movements of lateral and medial rectus?
Test abduction and adduction of the eye
How do you test the action of the superior oblique?
Move the eye to the medial position then ask the patient to move the eye down
How do you test the action of inferior rectus?
Move the eye laterally and then move the eyeball down
How do you test the action of the inferior oblique muscle?
Move the eye into the medial position them move the eyeball upwards