CN- tests + lesions seen Flashcards
CNI
olfactory
any changes in sense of smell
get pt to smell an object eg. peppermint [cover each nostril and test one at a time]
CNI pathology
bilateral anosmia= usually nasal not neurological
eg trauma, smoking, old age, URTI, Parkinsons disease
unilateral asnosmia- blocked nostril, head trauma, subfrontal meningioma
CNII
- pupil- size [2-4mm- and alignment [strabismus?]
- visual acquity- pt keeps glasses on if wear normally, use snellen chart, cover one eye at a time
- visual inattention [wiggle both hands, pt only sees one hand wiggle, indicates neglect]
- visual fields= map it out if pt has diff visual fields to you
- ishihara plates- test colour vision
- fundoscopy- absent red reflex= neuroblastoma/cataract.
- DISC: colour, contour, cupping;
- RETINAL VESSELS: AV nipping, neovascularisation, silver wiring;
- MACULA; anny drusen present ie. lil calcifications- seen in macular degeneration,
CNIII
H test
direct and consensual light reflex [and swinging light test to check for RAPD- seen in optic neuritis/retinal detachment/ direct optic nerve damage/infection]
accomodation reflex- should see constriction + convergence bilaterally
CNIII pathology
ptosis- damaged superior levator palpebrae
affected eye: down and out
opthalmoplegia in all directions except up and in
pupil ‘dilation’ = vital, distinguishes medical neerve palsy from surgical.
IV
trochlear nerve
supplies superior orbital muscle
IV pathology
eye is turned up and in [cos action of superior oblique is unopposed]
vertical diplopia [WORSE ON DOWNGAZE]
Person finds it hard to walk down the stairs
V
trigeminal
V1- opthalmic
V2- maxillary
V3- mandibular
sensation and motor to face esp muscles of mastication [temporalise + masseter]
inspect for any wasting above zygomatic arch
palpate masseter + temporalis
open jaw against resistance, move side to side
use cottonwool to test all sensory areas of face
pain test with neuro tip
corneal reflex/gag reflex
CN V pathology
long term V palsy- MND, myotonic dystrophy
loss of pain- = ipsilateral brainstem problem
herpes zoster in CNV ganglion
VI
abducens
inability to abduct affected eye
diplopia worse when looking in paretic muscle + worse on distance than near
CNVII
inspection - look for angles of mouth, asymmetry for peaky eyes, asymetry in patient folds.
test motor- lift eyebrows + dont lemme push down, squeeze eyes dont lemme push apart, puff out cheecks, show your teeth. purse lips together and tipp togetjer!
check for tast anterior 2/3rd of tongue
CNII pathology
UMN signs= loss of facial movement ipsilaterally but with forehead sparing [cos forehead is bilaterally innervated]. unilateral = CVA. bilateral = MND, pseudobulbar palsy.
LMN signs =loss of all movement ipsilatterally. unilateral = demyelination, bells palsy, cerebellopontine angle lesions. bilateral= GBS, MS…
Bells palsy- idiopathic, may be viral related- get unilateral LMN VII paralysis
Ramsay hunt- herpes zoster affecting geniculate ganglion, patch of herpes rash on external ear.
CNV III
changes in hearing/balance?
rinnes- tuning force against mastoid process, then put against ear opening [AC > BC = normally, also seen in sensorineural cases… BC > AC cos you’re not breath.
weber’s put it in centre of forehead, ask pt if sounds louder on one site [feels the same]
balance- stand on one leg with eyes closed/walk in straight line with eyes closed.
CN VIII pathology
AC > BC [normally]
AC > BC = normall/low in v v ultra thin peopl
BC > AC [in conductive]
webers test- is normally heard in both ears.
in neural deafness- pain heard best in intact ear
balance- if bad: consider physio…
