Neuro L3

what forms the outermost layer of the brain?

gray matter

what makes up the sulci and gyri?

gray matter

what makes the central aspect of the spinal cord and looks like a horn shape structure?

gray amtter

the gray matter receives information from _____ matter

white

what forms the central aspect of the brain?

white matter

what forms the peripheral aspect of the spinal cord (ascending and descending pathways)?

white matter

white matter is mostly made up of what?

axons coated with myelin

the spinal cord receives sensory info via _____ pathways from the extremities

ascending

relays info to the brain

afferent neurons

extends from skin receptors and runs to dorsal root ganglion into posteior horn of gray matter in spinal cord

first order neuron

carries sensory impulses to subcortical areas in thalamus

second order neuron

carries impulses to cerebral cortex

third order neuron

how many ascending pathways do we have?

10

match the ascending pathway to the description: spinothalamic tract

-pain and temp

-light touch

match the ascending pathway to the description: posterior column

-proprioception and stereognosis

-light touch

-vibration

match the ascending pathway to the description: spinocerebellar tract

-unconscious proprioception

What is the spinothalamic tract order from when someone receives input and up to the brain?

1. dorsal root ganglion

2. substantia gelationosa (dorsal horn of spinal cord) (cross over)

3. contralateral spinal cord

4. brain stem

5. thalamus

6. postcentral gyrus

injury to the sPinoThaLamic tract what happens?

loss of PAIN and TEMP sensation contralaterally and some loss of LIGHT TOUCH

What can cause spinothalamic tract injury?

-trauma

-syringomyelia

-anterior spinal artery syndrome

-thalamic pain syndrome

what is syringomyelia?

cystic enlargement of central canal of spinal cord = loss of normal flow of CSF

what type of birth defect can cause syringomyelia?

chiari malformation type 1

syringomyelia can cause loss of sensation in what type of distribution?

cape-like

what is anterior spinal artery syndrome?

infarction or hyperflexion injury

what are the sx of anterior spinal artery syndrome?

-sudden onset

-loss of pain and sensation B/L

-flaccid and areflexic paraplegia

-urinary incontinence

-vibration and proprioception are PRESERVED (posterior column)

what is thalamic pain syndrome?

post stroke pain syndrome can cause burning/gnawing pain to contralateral side (first will lose all sensation to contralateral side)

posterior column crosses at the ____

brain stem (medullary tegmentum)

injury to the posterior column tends to cause______ sx

ipsilateral

spinothalamic tract crosses over at the _____

dorsal root (spinal cord)

the posterior column is involved in what functions?

-fine touch

-two point discrimination

-conscious proprioception

-pressure and vibration

what are some common posterior column injuries?

-tabes dorsalis

-vit B12 deficiency

-brown sequard syndrome

what is tabes dorsalis?

Demyelination of posterior columns (from syphilis)

What disease causes these sx:

-delay sensory input

-loss of reflexes

-dec in vibration

-charcot joints

-argyll robertson pupils

tabes dorsalis

severe b12 def causes what sx?

-compromised nerve transmission

-paresthesias

-loss of vibration senses

c spine injury that involves only ONE side of the spinal cord

brown-sequard syndrome

what are the classic sx of brown-sequard syndrome?

-loss of pain and temp (contralateral)

-hemiparesis (ipsilateral)

-loss of vibration and proprioception (ipsilateral)

what controls unconscious proprioception?

spinocerebellar tract

spinocerebellar tract: no crossover of _____ portion but crossover of the ____ portion

1. posterior

2. anterior

list the spinocerebellar tract pathway:

1. golgi tendon organs/muscle spindles

2. dorsal root ganglion (clark's nucleus)

3. cerebellum

what are some injuries to the spinocerebellar tract injury?

-tabes dorsalis

-b12 def

-vit E def

-friedreich's ataxia

-brown-sequard syndrome

what is friedreich ataxia?

Degenerative disorder of the cerebellum and spinal cord (ataxia, loss of proprioception, spastic paralysis, loss of DTR)

what chromosome is affected in friedreich ataxia?

autosomal recessive disorder on chromosome 9

what are the 2 tracts in the descending pathway?

-pyrimidal tract

-extrapyrimidal tract

descending pathway: 1st order neuron-upper motor neuron

-cerebral cortex and brain stem

-spinal cord to anterior gray horn

descending pathway: 2nd order neuron-lower motor neuron

spinal cord to skeletal muscles

the pyramidal tract is aka

corticospinal tract

the pyramidal tract functions...

-controls limb and trunk movement

-controls head, neck, and face movement

-motor cortex to LMN of cranial nerves

if you get an injury of the pyramidal tract and it is above the medulla then the sx will be

contralateral

if you get an injury of the pyramidal tract and it is below the medulla then the sx will be

ipsilateral

where is the extrapyramidal tract located?

brain stem

the extrapyramidal tract controls what?

-muscle tone

-balance

-posture

-modulator of motor response

what are the sx of an extrapyramidal tract injury?

-hypokinetic sx (slow movement, loss of pendulation with walking)

-hyperkinetic sx (athetosis, chorea, myoclonus, tremors)

what is athetosis?

writhing movements

upper or lower motor neuron injury?

-spastic paralysis

-limited muscle atrophy

-NO fasiculations

-hyperreflexia

-babinski reflex may be present

upper

upper or lower motor neuron injury?

-flaccid paralysis

-significant atrophy

-YES fasiculations

-hyporeflexia

-babinski NOT present

lower

Wernicke's area is in what cerebrum lobe?

temporal lobe

the "senses" area is in what cerebrum lobe?

parietal lobe

cerebellar injuries cause what kind of signs/sx?

-ataxia (gait distrubances)

-balance issues

-weakness

-coordination issues

-tremor

What is Amyotrophic Lateral Sclerosis (ALS)?

Also known an Lou Gherig's disease, ALS is a motor neuron disease which can lead to paralysis.

ALS includes mixed upper and lower neurons sx, which tracts in UMN and LMN might we see sx from?

UMN: corticospinal tracts

LMN: anterior horns and grey matter

ALS is fatal within how many years?

3-5years

how is ALS fatal?

pulm infx MCC of death

in ALS, there is difficulty with swallowing, chewing, coughing, talking, due to ______ involvement

bulbar (CN 9, 10, 11, 12)

what is dysarthria?

slurred speech

what dz has these sx?:

-drooping palate

-depressed gag reflex

-weak cough

-pooling of saliva in pharynx

ALS

What is the key tx of ALS?

noninvasive ventilation 4hrs/d (start with maximal inspiratory pressure less than 60cm h2o)

how do we control drooling in ALS?

-decongestants

-anticholinergics

what rx do we give for pseudobulbar effect in ALS?

dextromorphan/quinidine

what is absolutely necessary that the pt receives if they get dx with ALS?

refer to palliative care

what are the typical EMG findings in ALS?

denervation and reninnervation...

-changes in cervical, thoracic, and lumbar region

-2 spinal regions and bulbar musculature

what are the 2 types of reactions with tertiary syphilis?

-hyperproliferative gummatous reaction

-diffuse inflam that involves CNS, large arteries

gummatous lesion

CSF findings: + spinal fluid serology, lymphocytic pleocytosis, inc protein

tertiary syphilis

tertiary syphilis causes what dz?

tabes dorsalis

what tests are done to confirm syphilis?

VDRL

RPR

what is used to tx syphilis?

penicillin or ceftriaxone (if pcn allergy)

what is the Argyll Robertson pupil?

sign of tertiary syphilis - constricts with accommodation but is not reactive to light

what causes guillain barre syndrome?

Campylobacter jejuni from undercooked or raw poultry

in GBS, where does weakness start?

in the extremities and makes its way to the muscles of respiration

how to tx with GBS?

plasmapheresis or IVIG and respiratory toileting

elevated MMA and homocysteine levels, what dz?

pernicious anemia

tx for pernicious anemia?

parenteral b12 (preferred over oral)

in poliomyelitis, we see involvement of what neuro areas?

anterior horn involvement

LMN involvement

polio is highly contagious through what route?

fecal-oral

abortive/nonparalytic/paralytic polio?

-fever

-HA

-vomit

-diarrhea/constipation

-sore throat

abortive

abortive/nonparalytic/paralytic polio?

-abortive sx +

-meningeal irritation

-muscle spasms

-absence of paralysis

nonparalytic

abortive/nonparalytic/paralytic polio?

-flaccid assymetric paralysis

-bulbar involement (CN 9 and 10)

paralytic

what type of labs would we do if someone has polio?

-throat washing

-stool studies

-CSF (inc opening pressure)

which US president had polio?

Franklin D. Roosevelt

decorticate posturing

characterized by upper extremities flexed at the elbows and held closely to the body and lower extremities that are extended

(this is a sx, not a dx)

what is a pathologic response to noxious stimuli?

decorticate/decerebrate posturing

decerebrate posturing

-adduction and internal rotation at the shoulder

-extension of elbows with flexed wrist/fingers

-extension at the knees with plantar flexion of the ankle and extension of the toes

(this is a sx, not a dx)

what is a more severe presentation? decerebrate or decorticate?

decerebrate