Peripheral organisation of cranial nerves Flashcards
Name cranial nerve I
Olfactory nerve
Where in CNI derived from?
The olfactory bulb, which sits just under the frontal cortex over the frontal bone and ethmoid bone
Function of CN I?
Sensory for smell
Name CN II
Optic nerve
What foramen does CN I pass through?
Olfactory foramen
What is the optic canal a foramen for?
Optic nerve and ophthalmic artery
What passes through the superior orbital fissure?
Cranial nerves III,IV, VI and the first part of V
Ophthalmic vein
Where do the extraocular eye muscles attach?
The outside of the eye
What are the 6 extraocular eye muscles?
4 rectus muscles: superior, inferior, medial and lateral
2 oblique muscles: superior and inferior
Where do the four rectus muscles originate and attach?
Originate from common tendinous ring and attach to the sclera, anterior to the equator of the eye
Describe the passage and attachment of the superior oblique muscle
Travels up the medial side of eye and goes to trochlea which is a pulley. Goes through pulley to insert in sclera posterior to equator
Where does the inferior oblique muscle emerge from and insert into?
Emerges from maxilla inserts into sclera posterior to equator of the eye
What is the name of CN III?
Occulomotor
Which two muscles does the occulomotor nerve NOT supply
Superior oblique and lateral rectus
What cranial nerves supply superior oblique and lateral rectus?
Superior oblique= IV
Lateral rectus= VI
Where do oculomotor parasympathetic fibres supply?
Pupil/ intrinsic muscles of the eye
Oculomotor parasympathetic fibres travel to ciliary ganglion
What is the action of medial rectus?
Adducts (turns eye in)
What is the action of lateral rectus?
Abduct (turns eye out)
What is the action of superior rectus?
Elevation and adduction
What is the action of inferior rectus?
Depression
What is the action of superior oblique
Intorts