cranial nerves for dentists Flashcards
cranial nerves
olfactory optic oculomotor trochlear trigeminal abducens facial vestibule cochlear glossopharyngeal vagal accessory hypoglossal
olfactory
smell
nasal epithelium to olfactory bulb
optic nerve
vision
symptoms - loss vision blurry loss of colour/field
signs - reduced visual acuity, visual defects, impaired colour vision
common aetiologies for optic nerve issues
inflammation
nutrition
vascular
raised ICP
oculomotor
eye movement
parasympathetic innervation of pupil
signs and symptoms for oculomotor nerve
symptoms - double vision, droopy eyelid signs - ptosis down and out eye pupillary dialtion
trochlear nerve
eye movement
intorsion
superior oblique muscle
symptoms and signs of trochlear nerve
symptoms - double vision
signs - head tilt, eye movements normal
aetiologies - head injury
microvascular
trigeminal
3 branches
opthalmic
md
mx
function and symptoms for trigeminal
sensation of skin mucous membranes and face
motor to masseter and temporalis
symptoims
- facial pain or sensory disrtubance
abducens nerve
longest cranial nerve eye movement (lateral rectus) symptoms - double vision signs - reduced abduction
aetiologies for abducens
raised ICP
ischaemia
inflammation
facial nerve divisions
temporal zygomatic
buccal
mandibular
cervical
function facial nerve
muscles of facial expression
taste to anterior 2/3
parasympathetic to lacrimal, sub m and sub lingual glands
symptoms of facial nerve
facial weakness
upper - weakness of forehead
lower - weakness of hemiface
common aetiologies for facial nerve
upper - stroke
lower
- inflammation
vestibulocochlear
balance and hearing symptoms loss of hearing vertigo signs positive impulse test
glossopharyngeal nerve
funciton
sensation from tonsils pharynx, middle ear poster 1/3 tongue
symptoms and signs of glossopharyngeal nerve
Symptoms - loss of taste at back of tongue - impaired swallowing signs - loss of gag reflex - loss of taste in posterior 1/3 tongue
aetiologies for glossopharyngeal nerve
- vascular (stroke)
- inflammation
- skull base pathology eg masses or meningeal infiltration
vagal nerve - function signs and symptom
Funciton - motor supply to pharynx and larynx (motor arm of gag reflex) - palatoglossus ( of tongue) - palatoglossus - parasympathetic supply to all organs except adrenals Symptoms - change ins speech and swallowing Signs - dysphonia (quiet/hoarse voice) - impaired cough - loss of gag relef
accessory nerve
motor supply to trapezius and SCM
weakness of shoulder shrug and head turn
hypoglossal nerve
motor supply to tongue except palatoglossal
altered speech and swallowing
tongue weakness, wastimg
aetiologies
- stroke
degenerative
cavernous sinus
presence of multiple nerve palsies may lead to involvement of cavernous sinus
eg abnormal; eye movement may indicate involvement of several of the nerves in this area
skull base
pathology involving the skull base
inflammation may start to affect adjacent cranial nerves
important to consider when there are several palsies found on examination
