Head 3 (nerves) Flashcards
Which cranial nerves carry parasympathetic pre-ganglionic fibers with them
3, 7, 9 (to the head)
10 (to cervical, thoracic, and abdominal viscera)
which cranial nerves are sensory
1, 2, 8
Which cranial nerves are mixed
5, 7, 9, 10
Which cranial nerves are motor
3, 4, 6, 11, 12
List the cranial nerves
1 - olfactory
2 - optic
3 - oculomotor
4 - trochlear
5 - trigemal
6 - abducent
7 - facial
8 - vestibulocochlear
9 - Glossopharyngeal
10 - Vagus
11 - Accessory
12 - Hypoglossal
Which cranial nerves are involved in eating/eliminating
5, 7, 9, 10, 12
which is the largest cranial nerve
Trigeminal n
List the branches of the trigeminal nerve and if they are sensory, motor, or mixed and which foramen each exits
V1 = Opthalmic, sensory (to eye and adnexa), orbital fissure
V2 = Maxillary, sensory, round foramen
V3 = Mandibular, mixed, oval foramen
Origin of Trigeminal n
Motor nucleus: pons
Sensory larger root: trigeminal ganglion
Describe the shape and location of the trigeminal ganglion
aka semilunar ganlion
crescent shape
locates in cranial cavity, outside the brain
What is in the trigeminal ganglion
Is a sensory ganglion containing cell bodies of pseudounipolar sensory neurons, similar to the dorsal root ganglion of the spinal cord. Gives the V1, V2 & the sensory part of V3 (mandibular)
Maxillary nerve origin
Trigeminal ganglion
Maxillary nerve course
Runs on cavernous sinus (with ophthalmic and 3) and passes through round foramen (orbitorotundum in Ru.)
Then goes to alar canal (in canine and equine) and rostral alar f.
to Ptyerygopalatine fossa to maxillar foramen to infraorbital canal and infraorbital f.
Maxillary nerve branches
Zygomatic, Pterygopalatine, infraorbital (continuation of maxillary n)
What are the branches of the zygomatic n
Zygomaticotemporal
Zygomaticofacial
What are the branches of the pteryogopalatine and what do they supply
Lesser palatine - soft palate
Greater palatine - hard palate
Caudal nasal - nasal cavity and maxillary sinus
What does the infraorbital n do
Runs in infraorbital canal and supplies the upper dental arcade via the caudal, middle, and rostral superior alveolar branches and continues outside the canal
What does the infraorbital n divide into and when does it divide
Outside the canal → divides into:
External nasal
Internal nasal
superior labial
What runs in the infraorbital canal and name its two openings
Infraorbital VAN
Caudal opening = maxillary foramen
Rostral opening = infraorbital foramen
Mandibular n course
Passes through oval foramen (foramen lacerum in horse)
short course ventrally to enter mandibular foramen of mandible
passes through mandibular canal and emerges at mental foramina as mental n.
Which main group of muscles does the mandibular n supply?
muscles of mastication (except caudal belly of digastric)
also supplies mylohyoideus, tensor veli palatini, and tensor tympani
List the motor branches of the mandibular n and what muscle they innervate
masticator -> massester m and rostral belly of digastric
deep temporal -> temporalis m
deep pterygoid -> pterygoid mm
mylohyoid -> mylohyoid m
tensory veli palatini -> tensory veli palatini m
tensor tympani n -> tensor tympani n m
List the sensory branches of the mandibular and what area they supply
Auriculotemporal - skin near rostral part of ear and eye (note: Gives sensation to same field for which the dorsal buccal of 7 provides motor innervation)
buccal - inside cheek
lingual - general and special sense of tongue
inferior alveolar - all lower teeth
mental - skin of chin
Describe the auriculotemporal n branches
Branches to transverse facial n and communicating br with dorsal buccal of 7
Facial nerve course
Origin: medulla oblongata at lateral part of trapezoid body
through Stylomastoid foramen
Very superficial under skin on lateral side of face
Which nerve passed through middle ear and can be affected by otitis media
Facial n
What does facial nerve do
Muscles of facial expression
Taste, rostral 2/3 of tongue
secretions (saliva, lacrimal, nasal)
Note: it is the only parasym supply to lacrimal gland
Name the three main branches of the facial nerve
Auriculopalpebral
Dorsal buccal
Ventral buccal
What does auriculopalpebral n do
Motor to orbicular oculi - muscle that closes eyelid
What does supraorbital n do and what is it a branch of
Sensory to upper eyelid
Branch of CN 5 ophthalmic nerve
Glossopharyngeal n origin and foramen
Lateral aspect of medulla oblongata and goes through jugular foramen
Glossopharyngeal n function
motor to pharynx
sensory to pharynx and carotid sinus (baro and chemo receptors)
Special sense for tastes in caudal 1/3 of tongue
parasympathetic to zygomatic and parotid salivary glands
Vagus n origin and foramen
Lateral aspect of medulla oblongata and goes through jugular foramen
note: longest CN
What does vagus n do
parasymp. innervation to viscera of pharynx, nech, thorax, and abdomen
motor and general sensory to soft palate, pharynx, larynx, trahea, esophagus, thoracic viscera, and abdominal viscera
Few special sense (taste from epiglottis)
What are the important branches from the vagus and what do they do
Cr laryngeal n: motor to one laryngeal n, sensory to laryngeal mucosa
Ca. laryngeal n: continuation of the recurrent laryngeal n and motor to laryngeal mm
What does the man’s face represent?
Otic Ganglion
1) Sensory branches (buccal n, lingual n, inf. alveolar n)
2) tensor veli palatini n
3) Temporalis m
4) medial pterygoid m
5) masseter m
6) Lateral pterygoid m
7)Tensor tympani n
How is accessory n unique
only cranial n that does not take part in innervation of head structures
What can occur with a trigeminal nerve injury
Trigeminal Neuritis: Results in sensory deficit of the face and dropped jaw (paralysis of the muscles of mastication).
Note: Wear gloves on dealing with any acute neurologic
disease (like trigeminal neuritis) as rabies is a
differential diagnosis, especially in unvaccinated
animals.
Accessory n course
Passes through F. magnum to join medullary root and exit via jugular. foramen
What are differentials for temporalis and masseter muscle atrophy
Masticatory muscle myositis
Trigeminal neuropathy
What does accessory n do
Motor to omotransversarius, cleidocephalicus, trapezius, and sternocephalicus
1) Auriculotemporal n
2) Mylohyoid n
3) Inferior alveolar
4) Lingual n
Hypoglossal n function
motor to all muscles of tongue
Describe the path of the inferior alveolar n
Enters the mandibular canal → lower dental
arcade
It exits the mental foramina as the mental
nerves.
Hypoglossal n course
Origin: Ventral(not lateral!!) aspect of medulla oblongata (motor nucleus of hypoglossa)
exits hypoglossal canal and runs lateral to ext. carotid a. with linguofacial trunk (horse and ruminant) or lingual a (dog)
Facial nerve sensory innervation
inner pinna
special sensory for taste for rostral 2/3 of tongue