Neuro Unit one

CN orginations

• 1&2 from the cerebrum

• 345 are from the midbrain

• 5678 are from the pons

• 9,10,11,12, and ish 5,7,8 from then medulla

spinal nerves

• cervical C1-C8

• thoracic is T1-T12

• Lumbar L1-L5

• Sacral nerve S1-S5

• coccygeal is one nerve

CN1

olfactory

• orginated from the cerebrum and is sense of smell

• sensory

CN 2

optic nerve

• sesnory

• orginates from the cerebrum

• sesnory part of pupil reflex

• VA, feilds,

CN3

occulomotor

• orginated from the midbrain

• test by EOMS

• motor part of the pupillary reflex

monocular vision loss causes

one eye gone bye bye

optic neuritis, optic atrophy, glaucoma, RD, CRVO/CRAO

bitemporal hemianopia

is an optic chiasm lesion can be from pituitary tumor or craniopharyngioma

homonymous hemianopia cause

(same side vision loss so nasal one one side and temporal on the other is from contralateral optic tract lesion ex MCC occlusion

homonymous inferior quadrantanopia

contralateral parietal (upper) optic radiation lesion

homonymous superior quadrantanopia

contralateral temporal optic raditation lesion ex MC occlusion

homonymous hemianopia with macular sparing

contralateral occipital visual cortex lesion ex posterior cerebral artery occlusion

relative afferent pilillary defect

defect in the direct response

marcus gun pupil

dilation of pupils

could be RD, ischemia, or optic neuritis

argyll robertson pupil

no constriction to light but will with accommodation testing

hallmark of tertiary syphilis

what muscles does the CN 3 control

(all but lateral rectus and superior oblique)

Medial Rectus ▪ Inferior Rectus ▪ Superior Rectus ▪ Inferior Oblique ▪ Pupil Constriction ▪ Accommodation

what would occur with oculomotor nerve injury

• diplopia

• dilated pupil

• fixed lateral position

• ptosis

skippied 4 and 6

CN 5

trigeminal nerve

• sensory division: light tough and sharp-dull

• motor division: putriod muscle and masserter muscle plus temporalis

3 divisions= opthalmic, maxillary, and mandibular

CN 7

facial

• motor: muscles of expression

• ssensory: anterior 2/3 of the tongue

UMN injury

• lower part of the face on contralateral side and there is contralateral weakness of facial muscles below level of the eye but you can still raise eyebrows

lower motor neuron injury to facial nerve

ipsilateral upper and lower facial weakness - unable to raise eyebrows

CN 8

vestibulchlear nerve

• vistibular nerve for balancer : test via caloric stimulation looking for nystagmus can also test via rromberg, past poiting test, dix hall pike

• cochlear nerve for hearing: weber/ rene/ whisper

weber test

• conductive hearing loss = sound goes to bad ear

• sensory hearing loss= sound goes to good ear

rinne test

• normal or sensineural hearing test is AC greater than BC

• is BC greater than there is conductive hearing loss

CN 9

glossopharyngeal

• motor stylopharyngeus muscle (muscle used in swallowing)

• sensory= posterior taste of 1/3, sensory part of the gag reflex

• plus PNS input to create siliva

CN 10

vagus

• motor: elevates the soft palat and posterior tongue, along with control of the intrinsic muscle of larynx for sound production

• sensory= Somatic sensory to the external auditory canal, posterior ear, and throat ▪ Visceral sensory to the larynx, esophagus, lungs, trachea, heart, and GI tract

efferent part of the gag reflex

damage to vagus nerve

• GERD

• hoarse voise

• increase in BP and HR

skipped last two CN

frontal lobe

• planning, problem slving, and judgement also impulse control and personality

injury to frontal lobe

• paralysis due to damage to motor cortex

• broca aphasia

• loss in flex thinking

• emotional lability

parietal lobe

• process and interprert somatosensory input such as touch and priprioception

injury in the parietal lobe

• inability to tell right and left ( gerstmann syndrome)

• apraxia

• loss of balance

• alexia (hard time reading)

temporal lobe

Process auditory info ▪ Process affect, emotion, language and visual perception ▪ Dominant side—understands language and learning ▪ Non-dominant side—Visual-Spatial material, music, non-verbal info ▪ Encodes memory

temporal lobe injury

Receptive aphasia (Wernicke’s aphasia) ▪ Incoherent sentences that are grammatically correct ▪ Impaired long-term memory ▪ Increased aggression

▪Vision loss/blindness ▪Hallucinations ▪Agnosia ▪Color disturbance or identification of objects`

damage to occipital lobe

cerebellum

Coordinates gait ▪ Maintains posture ▪ Cannot initiate muscle contraction but… ▪ Controls muscle tone and voluntary muscle activity

cerebellar injury

Symptoms • Loss in the ability to control fine movements • Maintain posture • Motor learning Most common causes of injury • Alcohol poisoning • Trauma • Multiple sclerosis • Tumors • Thrombosis of the cerebellar arteries

physical exam for cerebellar injury

Gait pattern, heel to toe walking ▪ Romberg Test ▪ Rapid alternating movements– hand flip and toe taps ▪ Check Speech ▪ Slurred speech or staccato voice ▪ Visual tracking looking for nystagmus ▪ Bilateral finger to nose testingPast pointing ▪ Reflex testing ▪ Hyporeflexia ▪ Heel to shin testing ▪ Trunk strength

overview of the brainstem

Gateway for neural impulses ▪ Receives input from motor cortex, cerebellum, basal nuclei, and afferent neurons ▪ Influences motor neurons in spinal cord ▪ Routes sensory information to the thalamus ▪ Regulates postural reflexes, coordinates eye/head movements ▪ Performs vegetative functions

is a pt had Ataxia ▪ Broad based gait with lean to affected side ▪ Tremor with fine motor movement (intention tremor) ▪ Horizontal Nystagmus ▪ Slurred speech ▪ Hypotonia ▪ Dysdiadochokinesia ▪ Inability to perform rapid alternating movements

think cerebellar injury

Midbrain

• regulated eye movement

• visual and auditory processing

• regulates arosal and conisciosness

• motor control via the substania nigra

• pain modulation

• sleep wake via reticular formation

• connection of pons and diencephalon

pons

Coordinates facial movement, hearing, and balance ▪ Site for lacrimation stimulation/mastication ▪ Controls rate and depth of breathing ▪ Transmits sensory information from PNS to thalamus ▪ Relay station between cerebrum and cerebellum ▪ Sleep Regulation ▪ REM sleep ▪ Pontine infarction can lead to locked-in Syndrome

medulla oblongata

▪ Regulates breathing ▪ Diaphragm control ▪ Regulates HR and rhythm ▪ Autonomic nervous system ▪ Regulates Bp ▪ Autonomic nervous system ▪ Swallowing, coughing, sneezing, vomiting control center ▪ Infarction can lead to respiratory dysfunction, irregular HR and Bp instability

brain stem injury

MCC is motor vehicle collision ▪ Signs and Symptoms ▪ Dizziness ▪ Uncoordinated movement ▪ Swallowing difficulties ▪ Nystagmus ▪ Cranial Nerve Palsies—III-XII ▪ Injury typically requires lifelong care/rehabilitation

below is lecture 3 i am not sure if i finsihed lecture 2

what are the three branches of the aorta

• left common cartiod

• left subclavain

• brachiocephalic

what does the brachiocehphalic branch into

right subclavain and right common cartiod

the right cartiod becomes the

internal caratiod and the veretebral

the internal carotid becomes the

anterior and MCA

where do the basilar artery come from

the basilar artery comes from the verterbral artery at the level of the pons as the end of the pons basilar becomes the posterior arterys

the vertebral arteries travel along cervical spine through

foramen magnum to become the basilar artery

what does the anterior cerebral artery innervate

• medial frontal and parietal lobes

• the cingulate gyrus

what does the middle cerebrala artery innervate

• frontal and pariteral lobe

• temporal lobe

• optic nerve

right carotiod artery occlusion

• upper and lower extermity weakness on contralateral side

• vision changes

left carotid artery occlusion

• aphasia caue wernikes and broacs area

• contralateral weakness of extermities

what does the vertebral arteries innervate

• brainstem

• cerebellum

• posterior cerebrum: occipital lobe, posterior temporal lobes

vertebral artery occlusion

• ataxia

• N/V

• vertigo

• diplopia

• swallowing difficulties

• facial numbness

• drop attacks (loss of muscle movement without any loss of conciousness

what does the cerevral artery innervate

• medial and inferior temporal lobe

• upper midbrain

• thalamus

• corpus callosium

posterior cerebral artery occlusion would cause

• homogenous hemianopa (same side vision loss will be contralateral to the occlusion)

• alexia (inability to read)

• visual agnosia (can not see fimilar objects and shapes)

• prospagonsia face blindness

• hemisensory loss

• hemiparesis: muscle weakness of one side of the body

• thalamic pain syndrome

• ataxia

what is posterior cerebral artery occlusion in b/l

corticol blindness

aneurysm of the posterior communicating arteries

CN 3 damage (expands on to the midbrain and therefore compresses the exit of CN 3

mengies superfical to deep

• dura

• arachniod

• pia

the dura levels

has tow layers the peropsteal and the meningeal they run down the length of the spinal cord

periosteal connects to the

calvarium

the meningeal layer connects to

arachniod mater

falx cerebi

fold in the dura mater that seperates cerebral hemispheres creates a channel for dural sinues

tentorium cerebri

sheilds the superior cerebellum and supports the occipital lobe

falx cerebeli

seperates the cerebellar hemisphers

diaphragma sellae

forms roof of sella turica opening and allows for stalk of pituitary gland

epidural space

above the dura and the skull supplies the the middle meningeal artery

epidural hematoma is more common in

younger adults

epidural hematoma is from

• mcc is skull fracture

• infection, abcess,

• tumor

• AVM

• and coagulopathy

what are the signs and sx of epidural hematoma

• confusion

• dizziness

• HA

• unilateral dilated pupil compression of CN III (compressed cause arterial bleed that in high pressure)

• N/V

epidural hematoma can have what presentations

• rapid neurological deterioration: altert to drowzy to confused to deep coma

• cushings reflex

what is cushings reflex

• widen pulse pressure

• bradycardia

• iregualr respirations (slow deep breaths- preiods of apnea- no respirations

epidural hematoma tx

• main goal is to decrease the ICP

• give mannotiol or hypertonic saline

• elevate the head

• drainage v craniotomy

when is craniotomy preformed

when ofer 30cm, focal deficits, or when GCS is less than 9

subdural hematoma

• collection of blood under the dural and above the arachniod level

• venous blood

acute cause of subdural hematoma

trauma in peds looks for signs of abuse

what are chronic causes of subdural hematoma

in elderly look for alcholo use disorder

sx of subdural hematoma

• HA

• N/V

• confusion

• personality changes

• slurred speech

acute tx of subdural hematoma

hypertonic perffered over mannitol

when to do surgery for sibdural hematoma

greater than 10mm thickness of clot

greater than 3 mm midline shift

GCS less than 9

what is the function of the arachnoid mater

avascular layer that primary function is cerebrospinal fluid metab: tranports CSF venous circulation

subarachnoid hem

blood between the arachnoid and pia mater

MCC aneurysm in circle of willis

signs and sx of subarcniod hem

worst HA of my life

diplopia

meningismus: HA, neck stiffnes, photophobia N/V

CN deficits

subarachnoid hem tx

• nimodipine for 21 days as vasospaasm prevention

• surgical endovascular clipping withint 24 hrs '

• monitor for hydrocephalus

• BP control less than 180

info on the pia mater

follows the contor of he gyrus and sulci

protective sheatha round blood vessels that enter and exit the brain

highly vascularized

dural sinuses

all sinues are valvless which means they have foward and backward flow (means pathogens can move around easily)

this flow pattern can lead to cavernous sinus thrombosis

wht CN injury is seen first when there is an issue with the dural sinuses

CN 6 means you can see pulsatile proptosis or opthalmoplegia of eye muscle (when there is a nsystagmus)

supedrior sagittal sinus lies

mideline within the falx cerebri

function of the superior sgittal sinus

function is to maintain CSF and homeostasis

carries waste and fluid away from cerebrum, falx cerebri and meninges

what happens if the superior sagittal sinus is imppaire

leads to an increase ICP and papiledema

cavernous sinus locations

sits on either side of sella turcica (the superior orbital fissure to petrous part of temporal bone posterioly

cavernous sinus contains

CN III, 4, opthalmic and maxillary nerve and CN 6

what venous supply does caernous sinus get

from opthalamic veins, superfical middle cerebral vein and sphenoparietal sinus

transervese sinus drains

cerebrum and inferior surface of the brain

when would you see transberse sinus complications

ear infections

cerebrospinal fluid is secreted by

choriod plexus

what is the largest sinus

superior sagittal sinus ( is for super )