Lecture 1/25 Flashcards
the 3 functions of the intraocular nerves are:
- motor
- sensory
- vasomotor
motor function of the intraocular nerves is
to muscles in the iris and ciliary body (autonomic NS: parasympathetic and sympathetic)
sensory function of the intraocular nerves is
sensation to the cornea and anterior segment of the uveal tract
vasomotor function of the intraocular nerves is
autonomic nerves involved with vessels of the urea tract (vascular tunic) and vessels supplying the retina
where is the entrance of the intraocular nerves?
at the posterior part of the eye, called ciliary nerves
how many short ciliary nerves are there
about 6-10
short ciliary nerves arise from
a small body called the ciliary ganglion (which is behind the eye in the orbit)
function of the short ciliary nerves
sensory and autonomic
how many long ciliary nerves
2 (1 on each side of the optic nerve)
long ciliary nerves arise from
a nerve way back in the orbit towards the apex called the nasociliary
function of long ciliary nerves
mainly sensory, but some sympathetic fibers go to iris dilator
where on the ciliary ganglion do the filaments for the short ciliary nerves arise?
filaments on the “corners” of the rectangular ciliary ganglion supply the short ciliary nerves
path of short ciliary nerves/ long ciliary nerve after they pierce the sclera
go to perichoroidal space and destination is anterior in the ciliary plexus
the short ciliary nerves pierce the sclera in a circle along with the ____
with posterior short ciliary arteries
other branches off the short and long ciliary nerves are
given off to sclera and choroid along its path
the long ciliary nerves enter the sclera alongside the _____
long posterior ciliary arteries
long ciliary nerves enter on the side of the optic nerve about _____ from the optic nerve
4mm
where is the ciliary plexus located?
in the pericilliary space
2 branches of the ciliary plexus are
- to the ciliary body and iris
2. to the sclera behind the (posterior) limbus
the ciliary plexus branch to the ciliary body and iris is what kind of nerve
sympathetic, parasympathetic, and some sensory
the ciliary plexus branch to the sclera forms the _____
episcleral network
from episcleral network, sensory nerves go anterior and form the:
pericorneal plexus
sensory innervation to the cornea
from episclera network, sensory nerves move posterior to supply:
the anterior half of the cornea
definition of a ganglion
a group of nerve cell bodies outside the CNS
shape of the ciliary ganglion
small, rectangular, and flat
location of the ciliary ganglion
posterior to the globe between the optic nerve and the lateral rectus
the ciliary ganglion receives (posteriorly) what 3 roots
- sensory root from naso-ciliary nerve
- sympathetic root from internal carotid plexus
- parasympathetic root from cranial nerve III
the ciliary ganglion gives off what and its anterior corners
the short ciliary nerves
which of these has a synapse in the ciliary ganglion (parasymp, symp, or sensory)
parasympathetic has a synapse in the ciliary ganglion
the 3 cranial nerves involved in EOMs
oculomotor (III)
trochlear (IV)
abducens (VI)
entrance and passing of oculomotor nerve (III)
enters into SOF and both branches (superior and inferior) pass through oculomotor foramen
superior branch of oculomotor nerve (III) supplies:
- superior rectus
- levator
inferior branch of oculomotor nerve (III) supplies:
- medial rectus
- inferior rectus
- inferior oblique
entrance and passing of trochlear nerve (IV)
enters through SOF, but goes OVER the top of the oculomotor foramen
trochlear nerve (IV) supplies the
superior oblique
abducens (VI) nerve passes and enters:
enters into the orbit through SOF and goes through oculomotor foramen
abducens (VI) innervates the
lateral rectus
sensory nerves are derived from:
CN V: trigeminal
CN V, trigeminal nerve, is the primary nerve for what structures?
face, nasal cavity, teeth, and mouth
trigeminal (V) nerve comes out as what 2 roots
large sensory root and small motor root
path of the sensory root of the trigeminal nerve (V)
comes out of the brainstem, travels on the floor of the cranium, and makes its way to the trigeminal ganglion (Gasserian)
3 branches that come off the trigeminal ganglion
- ophthalmic
- maxillary
- mandibular
ophthalmic branch of the trigeminal ganglion
passes through the SOF, and innervates the eye with sensory
maxillary branch of the trigeminal ganglion
goes into skull through foramen rotunda and goes to pterygoid-palatine fossa and supplies sensory to middle portion of the face
mandibular branch of the trigeminal ganglion
goes downward through the foramen ovale to the infratemporal fossa and supplies sensory to the lower face
ophthalmic branch of trigeminal nerve passes along _____ of cavernous sinus
lateral wall
what is the only sensory innervation to the globe?
ophthalmic branch of trigeminal nerve
just before this ophthalmic branch of trigeminal nerve goes into the SOF, it gives off what 3 branches?
- lacrimal
- frontal
- nasociliary
path of the lacrimal branch of the ophthalmic branch of trigeminal nerve
enters through SOF, goes over oculomotor foramen, passes along upper boarder of LR to the lacrimal gland, conjunctiva, and skin of the lid
path of the frontal branch of the ophthalmic branch of trigeminal nerve
enters through SOF, goes over oculomotor foramen, and supplies conjunctiva, skin of the brow, and skin of upper lid
supply from the nasociliary branch of the ophthalmic branch of trigeminal nerve
sensory supply to the globe from ciliary ganglion to short ciliary nerves to the eye and long ciliary nerves which come directly off nasociliary
parasympathetic preganglion fibers which travel where?
travel in CN III (oculomotor)
parasympathetic fibers synapse where?
in the ciliary ganglion right behind the globe
parasympathetic fibers enter the globe as:
short ciliary nerves (post ganglionic fibers)
parasympathetic fibers involved in
innervation of ciliary body for accommodation (90%) of the iris sphincter muscle for miosis (10%)
sympathetic fibers derived from
ganglion near spinal cord called superior cervical ganglion
sympathetic fibers then travel to the
internal carotid plexus
what is the internal carotid plexus
a network of these sympathetic nerves around internal carotid in carotid canal
from the internal carotid plexus to the eye, the sympathetic fibers have what 2 pathways
- trigeminal ganglion-> nasociliary -> long posterior ciliary nerves -> globe
- ciliary ganglion -> short ciliary nerves -> dilator of the iris
