neuro exam and pathology

basal ganglion purpose

affects movement and maintains muscle tone

diencephalon includes

thalamus, hypothalamus

thalamus purpose

process sensory impulses and relays to cerebral cortex

hypothalamus purpose

maintains homeostasis and regulates temp, HR, BP

also plays role in endo secreting hormones that act on pituitary

brain stem purpose

connect upper part of brain with spinal cord

cerebellum purpose

coordinates all movement and maintains body in upright space

ascending tract

transmit sensory info from receptors to brain

descending tract

send signals from brain to muscles to enable voluntary and involuntary movements

somatic NS

regulates muscle movements and response to sensations touch and pain

autonomic NS

connects internal organs to control of automatic functions like digestion and BP

number of spinal nerves

31

CN 1

olfactory

CN 2

optic

CN 3

oculomotor

CN 4

trochlear

CN 5

trigeminal

CN 6

abducens

CN 7

facial

CN 8

vestibulocochlear

CN 9

glossopharyngeal

CN 10

vagus

CN 11

accessory

CN 12

hypoglossal

upper neurons of corticospinal tract

cell bodies in motor strip of cortex and axons project impulses down brain stem to synapse with lower motor neurons

lower neurons of corticospinal tract

cell bodies in anterior horn and axons project impulses through cranial nerves or anterior roots of spinal cord and spinal nerves terminating at NMF mediating muscle contractions

where upper neurons cross over

medulla and spinal cord junction

damage to upper motor neurons effect

increased muscle tone or hyperreflexia

damage to lower motor neurons effect

decreased muscle tone and hyporeflexia

corticospinal tract function

voluntary movement and integration of skilled, complicated, or delicate movements

meds causing tremors

bronchodilators, SSRIs, anticonvulsants, ADHD meds

meds causing weakness

statins, steroids

meds causing neuropathy

chemo, dilantin, amiodarone

meds causing rebound headaches

aspirin, NSAIDs, triptans

mental status exam components

LOC, orientation, attention/concentration, language, memory, higher intellectual fxn, mood affect

LOC types

awake, confused, lethargic, obtunded, stupor, comatose

lethargic

drowsy but easily aroused with minimal stimuli

stupor

unresponsive, motor response with painful stimuli

obtunded

aroused with constant stimulation OTHER than pain

comatose

no motor response to any stimuli

attention/concentration test

spell world and in reverse, serial 7s (count back from 100)

language ability types

fluent, aphasia, dysarthria

aphasia

loss of ability to understand or express speech

dysarthria

poor articulation d/t motor function

language exam

name objects, repeat “no ifs ands or buts,” follow verbal/written commands, write complete sentence

olfactory nerve test

odor identification

optic nerve test

snellen eye chart, visual fields with finger wiggle

oculomotor nerve test

follow finger with eyes, opening eyes, pupillary constriction

trochlear nerve test

follow finger with eyes down and in

abducens nerve test

follow finger with eyes to the side

trigeminal nerve test

facial muscle strength by raising eyebrows against resistance, sharp, dull, and light sensation, corneal reflex with light

facial nerve test

facial expressions with smile and puff cheeks, taste

vestibulocochlear nerve test

hearing test, rinne/weber

glossopharyngeal nerve test

say “ah,” observe swallowing

vagus nerve test

gag reflex, swallowing

accessory nerve test

shrug and turn head against resistance

hypoglossal nerve test

stick out tongue

anosmia

loss of sense of smell

anosmia causes

sinusitis, virus, obstruction, tumor, MS, parkinsons’s trauma, radiation, chemo

visual acuity test

snellen chart

visual field test

finger wiggle

ocular fundus exam

fundoscopic exam

anopsia

defect in visual field

location of temporal retinal fibers

ipsilateral optic tract

location of nasal retinal fibers

contralateral optic tract

papilledema

swelling of optic disc

papilledema cause

increased intracranial pressure

pupillary reflex pathway

retina → optic nerve → optic chiasm → optic tract → midbrain → oculomotor nerve → pupillary sphincter

light reaction test

in dim light pt looks into distance while provider shines light obliquely into pupil

near reaction test

hold finger 10cm from eye and tell pt to look alternately at it and into distance

lateral rectus CN

CN 6 abducens

superior oblique CN

CN 4 trochlear

superior rectus CN

CN 3 oculomotor

medial rectus CN 

CN 3 oculomotor

inferior rectus CN

CN 3 oculomotor

inferior oblique CN

CN 3 oculomotor

strabismus

lazy eye

ptosis

droopy eyelid

nystagmus

rhythmic oscillation of eyes

nystagmus causes

ocular disease, drugs, disorders of labyrinth and cerebellar system

central nystagmus

from CNS dysfunction, low frequency but high amplitude, vertical MC, no affect from gaze fixation, does not exhaust

peripheral nystagmus

from vestibular system, high frequency but low amplitude, horizontal, may suppress with gaze fixation, can exhaust

CN 3 palsy

EOM weakness, ptosis, pupil involvement determines partial or complete

CN 3 palsy causes

PCOM aneurysm, stroke, tumors, trauma, myasthenia gravis

CN 4 palsy

eye rotates up and laterally

CN 4 palsy CP

diplopia worse with downward gaze, may tilt head to opposite side to compensate

MCC CN 4 palsy

trauma

CN 6 palsy CP

diplopia, inability to ABduct affected eye

causes of CN 6 palsy

increased ICP, tumor, ischemia, trauma, demyelinating disease

CN 5 motor function

mastication

CN 5 sensory function

sensory to face

CN 5 corneal reflex test

touch eye with cotton or gauze

trigeminal neuralgia CP

sharp, shocking pain along one branch of CN 5

trigeminal neuralgia population

middle aged women

MCC trigeminal neuralgia

superior cerebellar artery compression

bell’s palsy

unilateral CN 7 facial nerve palsy leading to hemifacial weakness and paralysis

bell’s palsy RF

pregnancy, DM, post URI

bell’s palsy CP

ear pain, high pitched sound intolerance, facial droop, loss of taste, unable to close eye

bell’s palsy PE

weakness and paralysis affecting UNILATERAL FACE ONLY

central facial palsy

upper motor neurons; upper forehead sparing, spastic muscles (increased DTR)

central facial palsy causes

stroke, MS, cerebral palsy, SCI