Cranial Nerves Flashcards
What cranial nerves are associated with the eye and ocular structures?
2,3,4,V1,V2,6,7
What does the afferent pathway do?
Take sensory information away from the organ.
-carry sensory information from cornea,iris,conjunctiva, and sclera
What areas give sensory information to the infratraochlear nerve?
- caruncle
- canaliculi
- lacrimal sac
- medial aspect of eye lid
- skin on side of the nose
How does the infratrochlear nerve run after it enters the orbit?
- it runs under the trochela
- runs along the upper border of the medial rectus then joins nasociliary nerve
What areas give sensory information to the anterior ethmoid nerve?
- skin from the center of the nose
- nasal mucosa
- ethmoid sinuses
What areas give sensory information to the posterior ethmoid nerve?
-ethmoid and sphenoid sinuses
How do the ethmoid nerves run?
–enter the orbit with their arteries then through a foramen within the frontoethmoid suture to join the nasociliary nerve
Where does sensory innervation exist in the cornea? Where does it not exist?
Yes: epithelium, anterior stroma, mid stroma
No: post stroma, Decemets membrane, endothelium
How many long ciliary nerves are there?
- 1 medial and 1 lateral
Describe the path of the long ciliary nerves
- go between sclera and the choroid to the back of the eye
- leave the globe 3mm on each side of the optic nerve
- then join nasocilary nerve
Aside from sensory information, what else do the long ciliary nerves do?
-transmit sympathetic fibers to dilator muscle of the iris
How many short ciliary nerves are there?
Many
Describe the path of the short ciliary nerves
- enter choroid and join choroidal nerves
- go to the back of the eye and leave as 6-10 short ciliary nerves
- exit the sclera as a ring around the optic nerve with the short ciliary arteries
- enter ciliary ganglion
- DO NOT SYNAPSE
- join nasociliary nerve
Name all of the nerves that join/ form the nasociliary nerve
- infratrochlear
- anterior and posterior ethmoid
- long ciliary nerves
- short ciliary nerve (sensory root from ciliary ganglia)
What is the path of the nasociliary nerve after it gets all of its input from the other nerves?
-pass through oculomotor foramen within common tendonous ring and superior orbital fissure to enter cranial cavity
Herpes zoster is associated with what sign? What does that indicate?
- Hutchinson’s sign
- nasociliary nerve is effected through infratrochlear nerve
- if posterior ciliary nerve is effected, the cornea is likely to be effected
What nerves make the frontal nerve?
Supraorbital and Supratrochlear
What areas give information to the supratrochlear nerve?
-skin, muscles of the forehead and upper eyelid