Anatomy of Cranial Nerves Flashcards
CNI is what kind of nerve?
special sensory
CNII is what kind of nerve?
special sensory
CN III is what kind of nerve?
motor and parasympathetic
CN IV is what kind of nerve?
motor
CN V is what kind of nerve?
CN V1= sensory
CN V2= sensory
CN V3 = sensory & motor
CN VI is what kind of nerve?
motor
CN VII is what kind of nerve?
special sensory, motor & parasympathetic
CN VII is what kind of nerve?
special sensory, motor and parasympathetic
CN X is what kind of nerve?
Sensory motor and parasympathetic
CN XI is what kind of nerve?
motor
CN XII is what kind of nerve?
motor
Where is the extra cranial part of the olfactory nerve?
within olfactory mucosa in nasal cavity
Which cranial foramina does the olfactory nerve pass through?
cribriform plate of the ethmoid bone
Where does the olfactory nerve connect with the CNS?
Synapse in the olfactory bulb
Pass through the olfactory tract to cortical areas
Where is the extra cranial part of the optic nerve?
Neurons of the retina travel posteriorly via optic nerve from the posterior hemisphere of eye through the orbit
Which cranial foramina does the optic nerve pass through?
Optic nerve passes through the optic canal in the middle cranial fossa
What is the intracranial part of the optic nerve?
Travels around the pituitary stalk to optic chiasm to form the optic tract
Where does the optic nerve connect with the CNS?
Diencephalon
How would you test CN I?
ask a patient to smell a familial smell while covering the contralateral nostril
How can you test CN II?
- acuity (snellen charts)
- colour (Ishihara plates- colour blindness)
- fields (four quadrants)
- reflexes (pupillary light reflexes)
- fundoscopy
Where is the oculomotor nerves connection to the midbrain?
midbrain (mesencephalon)
Where is the intracranial part of the oculomotor nerve?
Travels towards the orbit in the lateral wall of the cavernous sinus
What cranial foramina does the oculomotor nerve travel through?
superior orbital fissure (SOF)
What is the extra cranial part of the oculomotor nerve?
Passed through SOF into orbit and supplies ALL extra ocular muscles except two.
Parasympathetics synapse in the ciliary ganglion.
How would you test CNIII parasympathetics?
Use a light to check for pupillary constriction
Where does the trochlear nerve connect with the CNS?
Midbrain (mesencephalon)
Describe the intracranial part of the trochlear nerve
Travels towards the orbit in the lateral wall of the cavernous sinus
Which cranial foramina does the trochlear nerve pass through?
SOF
Describe the extra-cranial path of the trochlear nerve
Passed through the SOF into orbit and supplies only the superior oblique muscle
Where is the abducent nerves connection with the CNS?
Pontomedullary junction
Describe the intracranial part of the abducent nerve?
Travels towards the orbit within the cavernous sinus
Which cranial foramina foes the abducent nerve pass through/
SOF
describe the extra cranial path of the abducent nerve?
Passed through SOF into orbit and supplies only the lateral rectus muscle
Which cranial nerves does the H test look at?
CNs III, IV, VI
Describe the extra-cranial part of the vestibulocochlear nerve?
Axons from cochlear and vestibular apparatus
Which cranial foramina does the vestibulocochlear nerve pass through?
Internal acoustic meatus
In posterior cranial fossa
Describe the intracranial part of the vestibulocochlear nerve?
Travels posteromedially from the internal acoustic meatus to the pontomedullary junction
Where does the vestibulocochlear nerve connect with the CNS?
Pontomedullary junction
How can the vestibulocochlear nerve be tested clinically?
Rinne and Weber tests
Where does CN XI connect with the CNS?
Cervical spinal cord