Cranial Nerve V Flashcards
Describe the course of the trigeminal nerve from origin to its three divisions.
pons-> large sensory (great sensory nerve of the face) and small motor roots -> trigeminal (Meckel’s) cave in dura mater ->creates trigeminal (semilunar, Gasserian) ganglion which has the sensory cell bodies -> creates three divisions
- ophthalamic (sensory)
- maxillary (sensory)
- Mandibular (sensory + motor)
What kind of fibers does V have?
general sensory
branchial motor/special visceral
does NOT have parasymp fibers but CN III, VII, IX use it as a carrier
How do the three branches exit the skull?
- ophthalamic - superior orbital fissure
- maxillary - foramen rotundum
- mandibular - foramen ovale
What does the ophthalamic branch divide into?
- frontal
- lacrimal
- nasociliary
- What does the frontal branch come from?
- what does it branch into?
- what does it supply?
from ophthalamic branch (V1)
divides to:
- supratrochlear branch (medial)
- supraorbital branch (lateral, goes through supraorbital foramen)
sensory of eye muscles, scalp, and upper eyelid
What does the lacrimal branch come from? What does it do? What hitchhikes on it?
from ophthalamic branch (V1)
sensory to lacrimal gland and upper eyelid.
postganglionic parasympathetic fibers from the pterygopalatine ganglion through the zygomatic branch of maxillary nerve (V2)
What does the nasociliary branch come from? What does it branch to and what do they do?
from ophthalamic branch (V1)
- long ciliary (sensory to eyeball/cornea)
- posterior ethmodial (sensory to sphenoidal air sinuses and posterior ethmoidal air cells)
- anterior ethmodial (sensory to middle and ant ethmoidal air cells, meninges, nasal septum, inside nose and lower nose)
- infratrochlear (sensory to side of nose and medial upper eyelid) sensory root of the ciliary ganglion
Trace the posterior and anterior ethmoidal nerves.
Posterior ethmoidal: Enters the posterior ethmoidal foramen, sends sensory fibers to the sphenoidal air sinuses and the posterior ethmoidal air cells.
Anterior ethmoidal (Larger)
- Enters anterior ethmoidal foramen
- sends sensory fibers to the middle and anterior ethmoidal air cells.
- enters the cranial cavity at the side of the cribriform plate of the ethmoid and sends sensory fibers to the meninges.
- enters nasal cavity through the nasal slit; gives off sensory fibers to anterior part of the nasal septum and anterior parts of the lateral walls.
- leaves the nasal cavity as the external nasal branch, which supplies the skin of the lower half of the nose
- How does the maxillary division leave the skull and where does it end up?
- When there, what does in exchange fibers with?
- Where does it go then?
- goes from cavernous sinus. through the foramen rotundum to enter the pterygopalatine fossa
- (a) pterygopalatine ganglion (postg. parasym) (b) greater petrosal nerve (taste, preg. parasym from VII) (c) deep petrosal nerve (postg. sym from internal carotid plexus)
- proceeds through the inferior orbital fissure to the floor of the orbit becoming the infraorbital nerve. It passes along the infraorbital groove, canal, and foramen, and finally emerges on the face
In the ________, fibers get exchanged between 4 nerves/ganglion. They are, and they contribute these types of fibers.
pterygopalatine fossa
- maxillary branch (V3) - general sensory
- pterygopalatine ganglion - postg. parasym; after synapse with VII
- greater petrosal nerve - taste from VII (also preg. parasym but not mentioned in any branches)
- deep petrosal nerve - postg. sym. from internal carotid plexus 3 and 4 are nerves of the pterygoid canal
What are the branches of the maxillary nerve arising from the pterygopalatine ganglia? What types of fibers do they have?
- greater and lesser palatine (ALL types)
- posterior nasal branches and nasopalatine nerves (ALL except taste)
- pharyngeal branches (ALL except taste)
What are the branches of the maxillary nerve arising from the main trunk? What fiber types do they have?
- orbital (ALL except taste)
- zygomatic (ALL except taste)
- superior alveolar nerves (post, middle, ant) (ALL except taste)
- infraorbital nerve (no taste., no parasym)
Describe the course and innervation of the pterygopalatine ganglia maxillary nerve branches.
- greater and lesser palatine: descend through palatine canal and emerge via greater/lesser palatine foramen to reach palates of mouth
- posterior nasal/nasopalatine: pass into nasal cavity via sphenopalatine foramen to supply nasal septum and cavity
- pharyngeal branches: supplies mucus and glands of nasopharynx
Describe the course and innervation of the main branch maxillary nerve branches.
- orbital: passes through inferior orbital fissure to supply orbital wall and paranasal sinuses
- zygomatic: splits to zygomaticofacial and zygomaticotemporal; some of its postg. parasym fibers hitchhike on lacrimal nerve of V1
- superior alveolar nerves (post, middle, ant): supply maxillary sinus and top teeth, thus referred pain
- infraorbital: lower eyelid, side of nose, upper lip, front of cheek, nasal vestibule
What type of fibers is the mandibular division? What is its course?
general sensory (mostly) and branchial motor
Leaves the skull through the foramen ovale and enters the infratemporal fossa where it is connected to the otic ganglion (auriculotemporal nerve).