cranial nerves Flashcards
CNI
name?
function?
name: olfactory
function: sense of smell
CNII
name?
Function?
name: optic nerve
func: vision
CN III
name?
func?
name: occulomotor
func: pupillary constriction, opening the eye (lid elevation) and most extraoccular movements
CN IV
name?
func?
Name: trochlear
func: downward, internal rotation of the eye
CN V
name?
func?
name: Trigeminal
func:
1. Motor- temporal and masseter muscles (jaw clenching), lateral pterygoids (lateral jaw movement)
2. sensory- facial. Three divisions (opthalmic, maxillary and mandibular)
three sensory divisions of CN5 (trigeminal)
opthalmic, maxillary and mandibular
CN VI
name:
func:
name: Abducens
func: lateral deviation of the eyes
CN VII
name:
func:
name: facial nerve
func:
1. motor: facial mvmt, including facial expresion, closing the eye and closing the mouth
2. sensory: taste for salty, sweet, sour and bitter substances on the ant. 2/3 of the tongue
CN VIII
name:
func:
name: acoustic (vestibulocochlear nerve)
func: hearing (cochlear division) and balance (vestibular division)
CN IX
name:
func:
NAME: glossapharyngeal
func:
motor: pharynx
sensory: posterior portions of the eardrum and ear canal, the pharynx, and the posterior tongue (including taste (salty, sweet, sour and bitter)
CN X
name:
Func:
name: vagus
func:
motor: palate, pharynx and larynx
sensory: pharynx andlarynx
CN XI
name:
func:
name: spinal accessory nerve
func: motor- sternocleidomastoid and upper portion of hte trapezius
CN XII
name:
func:
name: hypoglossal
func: motor: tongue
what two nerves are in the cerebellopontine angle and are therefore vulnerable to tumors there?
CN VII (facial) and VIII (vestibulocochlear)
what is the cerebellopontine angle and what two optic nerves come out of it?
traingle formed by the cerebellum, upper medulla and midle cerebral peduncle.
- the facial and cestibulocochlear nerve emerge from the brainstem here
what are the two most common tumors in the cerebellopontine angle (and therefore affect the facial and vestibulocochlear nerves?)
acoustic neuromas (805) and meningiomas
the glossapharyngeal nerve (CN9) and vagus nerve (10) emerge from the brainstem where?
at the post-olivary sulcus (caudal to the cerebellopontine angle)
the optic nerve exits from…
the optic chiasm on the ventral surface of the diencephalon- rostral to the cerebellopontine angle
the trigeminal nerve emerges from the brainstem….
at the anerolateral surface of the pons (rostral and ventral to the cerebellopontine angle)
painless loss of central vision in both eyes, even if it’s worse in one eye than the other, in an 83 year old is likely due to…
age-related macular degeneration
two forms of age-related macular degeneration
1) atrophic macular degeneration (dry form)- pigmentary changes in maculae with no hemorrhage/scarring
2) exudative macular degeneration (wet form)- there’s a network of new vessel formation below the retina —> source of intraretinal hemorrhage and subretinal fluid (can contract with scar formation)
unlike age-related macular degeneration, central artery occlusion leading to central blindness would present…
as a sudden, unilateral, painless visual loss (age related would be bilateral, painless and either sudden or progressive)
nonproliferative diabetic retinopathy is characterized by…
microaneurysms, hemorrhages and exudates of the retina
like non proliferative diabetic retinopathy, proliferative diabetic retinopathy is characterized by microaneurysms, hemorrhages and exudates of the retina. But it also has…
neovascularization with extension of vessels into the vitreous
can a retinal detachment be seen?
yes, as a raised area of retina (unless there’s been hemorrhage into the vitreous)
what CN leaves the cribiform plate?
CN 1 olfactory
what CN + artery leaves the optic canal?
CN II (optic) + opthalmic art.
what CNs leaves the superior orbital fissure?
III (occularmotor), IV (trochlear), VI (abducens), V- V1 (ophthalmic of trigem)
what CN leaves the foramen rotondum
V- V2 (maxillary branch of the trigem.)
what CN leaves the foramen ovale?
V- V3 (mandibular branch of trigem)
what art enters the foramen spinosum?
middle meningeal art
what cn leaves the internal auditory meatus?
VII- facial
VIII- vestibulocochlear
what CNs leave the jugular foramen?
IX (glossopharyngeal) X (vagus), XI (spinal accessory)
what CN leaves the hypoglossal canal?
CN XII (hypoglossal)
what CN enters via the foramen magnum? what else enters there?
XI (spinal accessory). spinal cord and vertebral arts also enter there
recurrent larngeal nerve is a branch of the…
vagus
the recurrent laryngeal nerve innervates…
all intrinsic laryngeal muscles EXCEPT the cricothyroid, which is innervated by the external laryngeal nerve
what is the one intrinsic laryngeal muscle that the recurrent laryngeal nerve doesn’t innervate?
the cricothyroid- which is attached to the cricoid cartilage and thyroid cartilage
what does the cricothyroid, the one intrinsic laryngeal muscle that the recurrent laryngeal nerve doesn’t innervate, do?
contraction of this muscle stretches and adducts the vocal ligament
the chorda tympani branch of the facial nerve controls salivation from which glands?
submandibular and sublingual
the parotid gland is controlled by…
glossapharyngeal (IX)
which nerve innervateds the submandibular and sublingual glands?
Facial (VII)- specifically the chorda tympani branch
