Anatomy - Cranial Nerves Flashcards
what are the three parts of the course of a cranial nerve?
CNS
intracranial
extra cranial
what is the intracranial part of the course of a cranial nerve?
between the connection with the CNS and its base of skull foramina
what nerve exits the skull via the cribriform plate of the ethmoid bone?
CN I
what nerve exits the skull via the optic canal?
CN II
what nerve exits the skull via the superior orbital fissure?
CN III
CN IV
CN V1
CN VI
what nerve exits the skull via the foramen rotundum?
CN V2
what nerve exits the skull via the foramen ovale?
CN V3
what nerve exits the skull via the internal acoustic meatus?
CN VII
CN VIII
what nerve exits the skull via the jugular foramen?
CN IX
CN X
CN XI
what nerve exits the skull via the hypoglossal canal?
CN XII
what are the three divisions of the trigeminal nerve?
ophthalmic
maxillary
mandibular
where does the trigeminal nerve connect to the CNS?
pons
describe the intracranial part of the course of the trigeminal nerve?
passes inferior to the edge of the tentorium cerebella between the posterior and middle cranial fossae
where does CN V1 exit the skull?
superior orbital fissure
where does CN V2 exit the skull?
foramen rotundum
where does CN V3 exit the skull?
foramen ovale
what nerve supplies the skin over the angle of the mandible?
great auricular nerve
where does the facial nerve connect to the CS?
anterolaterally at the pontomedullary junction
describe the intracranial part of the facial nerve course
goes directly into the internal acoustic meatus in the posterior cranial fossa
what two base of skull foramina does the facial nerve exit the skull via?
internal acoustic meatus
stylomastoid foramen
where does the glossopharyngeal nerve connect to the CNS?
the lateral aspect of the superior medulla oblongata
where does the glossopharyngeal nerve exit the skull?
jugular foramen
where does the vagus nerve connect to the CNS?
lateral aspect of the medulla oblongata
inferior to CN IX
where does the vagus nerve exit the skull?
jugular foramen
what is the most distal structure supplied with parasympathetics by the vagus nerve?
splenic flexure of the colon
where do you touch to test the sensory supply of CN V1?
forehead
upper eyelid
tip of the dose
where do you touch to test the sensory supply of CN V2?
mid cheek
lower eyelid
upper lip
nostrils
where do you touch to test the sensory supply of CN V3?
lower cheek
lower lip
chin
how do you test the motor function of the trigeminal nerve?
ask the patient to clench their teeth and then open their jaw against resistance
how do you test the motor function of the facial nerve?
frown
close eyes tightly
smile
puff out cheeks
what fibres are carried in the spinal accessory nerve?
motor
how does the spinal accessory nerve connect with the CNS?
via cervical spinal nerve anterior rootlets
connects to the spinal cord
describe the intracranial part fo the course of the spinal accessory nerve
ascends through the foramen magnum
travels towards the jugular foramen
what is the base of skull foramen for the spinal accessory nerve?
the junction between the temporal bone and occipital bone
what muscles are supplied by the spinal accessory nerves?
SCM
trapezius
what fibre type is carried in the hypoglossal nerves?
motor fibres
how does the hypoglossal nerve connect to the CNS?
via rootlets that attach laterally to the pyramids of the medulla oblongata
what is the base of skull foramen for the hypoglossal nerve?
hypoglossal canal
