Trigeminal Nerve Flashcards
what are the 3 branches of the trigeminal nerve?
ophthalmic, maxillary and mandibular
what are the 3 exit points of the CN V branches?
supra-orbital notch, infra-orbital foramen, mental foramen
what bones make up the hard palate?
maxilla and palatine bone
where is the mandibular foramen?
on the inner surface of the mandible next to the lingula
where does the trigeminal nerve emerge from in the brainstem?
mid pons
where are the CN V nuclei located?
midbrain, pons and medulla
which CN V nuclei is located in the midbrain
general somatic afferent (sensory)
which CN V nuclei is located in the pons?
special visceral efferent and general somatic afferent
which CN V nuclei is located in the medulla?
general somatic afferent
where is the only location of the special visceral efferent nuclei of CN V?
pons
what type of sensory nuclei does the CN V have?
mesencephalic, chief sensory nucleus, spinal nucleus
what type of innervation does CN V have?
general sensory for most of the face, special motor for muscles of mastication
once the nerve roots of CN V emerge from the mid-pons where do they go?
they pass onto the apex of the petrous temporal bone where the trigeminal ganglion lies in a cave of dura mater (Meckels cave)
once in the trigeminal ganglion where does CN V1 exit?
superior orbital fissure
where does CN V2 exit the trigeminal ganglion?
foramen rotundum
where does CN V3 exit the trigeminal ganglion?
foramen ovale
what are the branches of CN V1
frontal, lacrimal and nasociliary
where does the frontal nerve come from and what does it divide into?
CN V1 and divides to supraorbital and supratrochlear
what does the frontal nerve (CNV1) supply?
skin of vertex and upper eyelid/forehead
where does the lacrimal nerve come from and what does it supply?
CN V1 and supplies lacrimal gland, skin of lateral upper eyelid and forehead
what does the nasociliary nerve come from and what does it give off
CN V1 and long ciliary nerve, anterior and posterior ethmoidal nerves, infratrochlear nerve
what does the anterior ethmoidal nerve supply and where does it come from?
comes from nasociliary nerve of CN V1 and continues as external nasal nerve to supply skin at tip of nose
what does shingles at the tip of the nose warn of?
disease developing into cornea
what does CN V2 reach once it goes through the foramen rotundum?
pteryogpalatine fossa
where does the pterygopalatine fossa lie?
just lateral to the upper aspect of the nasal cavity and nasopharynx behind the orbit and above the hard/soft palate
what are the branches of CN V2
ZYGOMATIC AND INFRA-ORBITAL , nasopalatine, greater and lesser palatine, pharyngeal, alveolar to upper teeth
where does the zygomatic nerve come from and what does it split into?
CN V2 and splits to zygomaticotemporal and zygomaticofacial
where does the infraorbital nerve come from and where does it exit?
comes from CN V2 and exits through infra orbital foramen
when CN V2 divides, what branches does it divide into and where do they go?
zygomatic and infraorbital braches to the orbit through the inferior orbital fissure
what does the infraorbital nerve supply
lower eyelid, cheek, nose and upper lip
where are the branches of the zygomatic nerve?
anterior temple and zygoma
where does the nasopalatine nerve enter the nasal cavity and where does it go from there
sphenopalatine foramen and passes via incisive canal to reach anterior hard palate
what are the alveolar branches of CNV2
posterior superior alveolar, middle superior alveolar and anterior superior alveolar
what are the 2 types of palatine nerves?
greater and lesser
where do the palatine nerves go
through the palatine canal
what CN V2 nerves supply the gingivae?
nasopalatine, greater palatine nerve through greater and lesser palatine foramen
what nerve supplies the soft palate?
lesser palatine nerve
once CN V2 has passed through the foramen ovale where does it go next?
to the infratemporal fossa
where does the infratemporal fossa lie in relation to the mandible?
posteriorly
what are the main branches of CN V3
auriculotemporal, buccal, mental, lingual, muscular
what are the trunks of CN V3
main, anterior, posterior
which nerves are part of the main branch of CNV3
meningeal branch, branch to tensor tympani, bransh to tensor veli palatini, nerve to medial pterygoid
which nerves are part of the anterior branch of CN V3
deep temporal nerves, nerve to lateral pterygoid, buccal nerve, masseteric nerve
which nerves are part of the posterior branch of CN V3
auriculotemporal nerve, lingual nerve, inferior alveolar nerve
what is the distribution of CN V3?
auricle, temple, lower lip, chin, cheek
which nerve supplies general sensation to the floor of mouth along with lower teeth and gums?
CN V3
which nerve supplies general sensation to the anterior 2/3rd of the tongue?
CN V3 via lingual nerve
where does trigeminal neuralgia occur?
in CN V3 (occasionally CN V2)
what does the buccal nerve supply?
cheek and lateral gum
what does the inferior alveolar nerve supply?
lower teeth, skin of chin and lower lip as mental nerve
what is the motor component of the inferior alveolar nerve?
supplying motor function to the mylohyoid and anterior belly of digastric
which nerve supplies the incisors and where does it come from
incisive nerve from the inferior alveolar nerve
what is the sensory supply of the anterior 2/3rds of tongue?
general sensory = mandibular division of CN V
taste = facial nerve
which nerve has the motor root for muscles of mastication
CN V3
explain the jaw jerk reflex
sensory information being passed through the trigeminal nerve into mesencephalic nucleus of trigeminal nerve into brainstem, connect to motor nucleus in pons and go to muscles
which area of the face does the trigeminal nerve never supply?
angle of mandible
with shingles, what is a Hutchinsons signs
cutaneous involvement of the tip of the nose
what does a positive hutchinsons signs mean?
increases likelihood of ocular complications
