CABS Topics Flashcards
What neuroglia cell is an important part of the blood brain barrier?
Astrocytes
Can your CNS or PNS regenerate?
PNS
What virus is associated with causing or triggering MS?
Epstien Barre Virus (EBV)
What cell mediated process drives MS?
B-cell mediated
How will MS typically start?
Clinically isolated syndrome that occurs for at least 24 hours
m/c symptom is optic neuritis
Can you repair myelin?
Yeah, you can
Can you repair axons?
No
What does the limbic system mediate?
Emotional response with memory and learning
What systems are being inhibited with Tourettes disorder?
Factors of the limbic and motor system
What is intracranial pressure?
BP in the brain (pressure excreted by fluids in the brain, CSF etc.)
What is the triad presentation for normal pressure hydrocephalus?
Dementia, gait alteration, and incontinence
(wacky, wobbly, and wet)
Gait alteration presents first m/c
In M. Gravis, what muscles are going to be attacked?
ocular, respiratory, head/neck, and limb muscles
What type of hypersensitivity is M. Gravis?
Type II
Why do you require surgery when your eye is injured?
Nerve, or structures get caught in sinus cavity
What are the cavities in the skull?
Cranial cavity, ethmoid sinus, nasal cavity, maxillary sinus, oral (buccal) cavity
Why are your occipital condyles important?
Articulates with C1, allows us to say “yes”
What is the thinnest part of the skull?
Pterion
What lies across the pterion?
Middle minningeal artery
What score requires intubation on GCS?
Score of 8 or less, they don’t have their gag reflex (there are exceptions)
What do you see (sign) on imaging in brain herniation?
Light bulb sign - lack of activity and metabolism
What is Cushing’s Triad?
Elevated ICP
Hypertension, Bradycardia, Irregular breathing
What is the most common type of brain herniation?
Uncal transtentorial herniation
What structure is being compressed in an Uncal Transtentorial Herniation and what are the physiologic signs?
Compression of CN III (oculomotor) causing ipsilateral fixed, dilated pupil
What type of posturing will be seen in a central transentorial herniation?
Decorticate posturing or decerebrate posturing (medical emergency)
What is happening in a cerebellotonsillar herniation?
Cerebellar tonsils are pushed through the foramen magnum (pushing on your life stick)
Sx - pinpoint pupils, flaccid paralysis, death!
What are the H-BOMBS?
Hypotension
Hypoxia
Hypo/Hypercarbia
Hyper/Hypothermia
Hypoglycemia
What is the respiration mediator in the brain?
CO2
Where is the bleed in an epidural hemorrhage?
Bleeding between the skull and dura mater, m/c in the temporal fossa (middle meningeal artery)
What is being torn in a subdural hemorrhage?
Tearing of the veins between the dura and arachnoid leading to collection of blood
What are common patient cohorts at risk for subdural hemorrage?
Elderly, ETOH abuse
What type of bleed has an interval where someone looses consciousness then has a a period of consciousness, and what is it called?
Epidural bleed, Lucid interval
What is an intraparenchymal hematoma?
Bleeding within the tissue of the brain (not a dural space), may have a single bleed or multiple
Maybe from penetrating or shearing trauma which break local vessels - m/c in the temporal or frontal lobes
Can diffuse axonal injuries heal?
No, because of the tearing of axons and vessels
If a patient has a neurologic change in status after initial imaging what would be your next management step?
Repeat imaging (always)
Will an initial (first injury) concussion cause structural damage?
No, structural damage only occurs with repeat concussions
How is an autonomic lesion going to present?
Can’t control what your supposed to - heart, bladder, breathing
What nerve is like the godfather of the autonomic nervous system?
Vagus Nerve
What is neurogenic shock?
Hemodynamic compromise resulting from autonomic dysfunction
When does spinal shock typically resolve?
24-73 hours, makes initial assessment of cord injury difficult (will I walk again?)
What level of the spine is neurogenic shock most commonly seen?
Thoracic spine
What structures are part of the limbic system?
Hypthalamus, Amygdala, Hippocampus, Thalmus
What is the role of the Hippocampus within the limbic system?
Memory conversion, episodic memory
What is the role of the Thalamus within the limbic system?
Relays information
What is the role of the Hypothalamus within the limbic system?
Homeostasis (parasympathetic/sympathetic nervous system balance) via mammillary bodies
What is the Amydala’s role within the limbic system?
Emotion
What is the basal ganglia?
Part of the limbic system, group of nuclei that help with motor, emotional, learning reward
Includes the caudate and the putamen (together = stratium)
What type of sensory are free nerve endings responsible for?
Temperature
Touch
Noxious
What type of sensory are meissner corpusles responsible for?
Shape and texture
What type of sensory are Ruffini endings responsible for?
Pressure and Heat
What are the two major pathways that lead to altered mental status?
Diffuse dysfunction (metabolic, cardiovascular, uremia, toxins)
Focal lesions
What are the red flags in altered mental status presentation?
Sudden Onset
Elderly
Headache
Drug Use
Trauma
Fever
Is altered mental status a diagnosis?
No, it is a symptom
Why does carbon monoxide cause delirium?
Decreased oxygen to the brain
What can’t be regulated in delirium?
Inability to regulate the arousal system (RAS) and alteration of the reticular activating system with the midbrain, thalamus, and hypothalamus
What does increased excitability with change in neurotransmitters cause in hyperactive delirium?
Inflammation
Decreased BBB function
Change in CBF
CNS metabolic derangements
What can cause agitated delirium?
Cocaine (increases dopamine)
Thyroid storm
Methamphetamines
Is agitated delirium life threatening?
Yes, can lead to death
What can cause hypoactive delirium?
CNS depressants
Metabolic disorders (liver or kidney disease)
What are the Wernicke’s encephalopathy acute phase clinical features?
Confusion
Opthalmoplegia
Ataxia
Thiamine (low)
What are the Korsakoff’s psychosis chronic phase characteristic findings?
Retrograde amnesia
Anterograde amnesia
Confabulation
Korsakoff’s psychosis
Where are plaques and tangles found most commonly in Alzheimer’s Disease?
Cerebral Cortex and Hippocampus
Who commonly gets diagnosed with frontotemporal dementia?
Younger adults, <60 years
What do prions cause within humans?
Neuronal loss
Increased proliferation of glial cells
No inflammatory response
Spongiform appearance of the tissue
What are prions?
(Infectious) misfolded protein particles that replace normal prion proteins - thought to have a role in memory and sleep
Why can Schwann cells repair?
Have Dynein protein (growth factor) that will encourage increased protein synthesis to the nucleus
What can block Dynein from repairing a Schwann cell?
Either scar tissue or damaged soma
What are two common electrolytes that can cause seizures?
Sodium and glucose
What can lower someones seizure threshold?
Physical and environmental stressors
What is epileptogenic focus?
Collection of neurons that are more sensitive, more readily stimulated to begin rapid, unnecessary firing (where seizure starts)
In relation to seizures, what is the major excitatory neurotransmitter and inhibitory neurotransmitter?
Glutamate = excitatory
GABA = inhibitory
If a seizure occurs for a long period of time what is can develop?
Mirror focus - this is when the epileptogenic focus can mirror image onto the other side of the brain (same location on opposite side)
What time of day do idiopathic seizures most likely occur?
In the morning
What is the most common age of onset for juvenile myoclonic epilepsy?
College age
Where do neoplasms classically present in children?
Infratentorial
Where do neoplasms classically present in adults?
Supratentorial
What is the most common presenting symptom of a CNS neoplasm and when does it most likely occur?
HA, in the morning
What are common signs and symptoms when the lesion is in the brainstem?
CN findings, elevated ICP (N/V, blurry vision, papilledema, CN VI palsy)
What are common signs and symptoms when the lesion is in the cerebellum?
Ataxia, falls, balance issues, elevated ICP
What are common signs and symptoms when the lesion is in the frontal lobe?
Weakness, personality change, cognitive symptoms, psychiatric sxs
What are common signs and symptoms when the lesion is in the occipital lobe?
Homonymous hemianopia
What are common signs and symptoms when the lesion is in the parietal lobe?
Numbness, paresthesia
What are common signs and symptoms when the lesion is in the temporal lobe?
Amnesia
What are common signs and symptoms when the lesion is in the dominant hemisphere?
Aphasia
What is the primary neurotransmitter int he sympathetic nervous system?
Norepinephrine (adrenergic)
What do splanchnic nerves assist with?
Help with vasoconstriction allowing BP to increase, assist vasculature
What is the primary neurotransmitter in the parasympathetic nervous system?
Acetylcholine (cholinergic)
What nervous system is going to be impacted in neurogenic shock?
Sympathetic because they are located primarily in the thoracic and lumbar spine
What are the catecholamines?
Epinephrine, norepi, dopamine
What is the number one job of the autonomic nervous system?
Vascular tone
What needs to occur for it to be defined as syncope?
loss of postural tone
What are the major types of syncope?
Reflex syncope (the neurologic source)
Orthostatic syncope
Cardiac arrhythmia
Structural cardiopulmonary disease
What is the #1 test you must order for a patient who suffered a syncopal episode or experienced pre-syncope?
EKG
What is subclavian steal syndrome?
The subclavian artery is stenosed proximal to the vertebral artery and causes reverse flow during times of exertion
What test should be completed when diagnosing and typing vertigo?
HINTS Exam
Head Impulse
Nystagmus
Test of Skew
What two divisions join to make the sciatic nerve?
Posterior and Anterior Divisions
What will result when the common fibular (peroneal) nerve is severed?
Foot drop
What will result when the tibial nerve is severed or compressed?
Leads to tarsal tunnel and will result in pain and neuropathy in the foot
What nerve can be compromised during a traumatic childbirth?
Pudendal nerve
Is there evidence of peripheral nerve injury on EMG in Type 1 Complex Regional Pain Syndrome?
No
What is the pain in Complex Regional Pain Syndrome caused by?
Neurologic inflammation causes release of neuropeptides causing pain
What sensation is impaired with small nerve fiber damage?
Decreased perception of pain, decreased temperature perception, burning, numbness, tingling
What sensation is impaired with large nerve damage?
Decreased light touch, loss of vibration or position sense
How does Vitamin B12 deficiency typically present with first?
Anemia, then neurologic symptoms (neuropathy)
What is Vitamin B12’s role related to the myelin sheath?
Maintain the sheath
When does Guillain-Barre Syndrome present?
After a respiratory or GI illness (4 weeks)
What is Guillain-Barre Syndrome?
Post infectious autoimmune peripheral demyelinating disease
What is the classic presentation symptom seen in Guillain-Barre Syndrome?
Symmetrical muscle weakness usually beginning in the legs and ascends
What is Brodmann’s area 17 primary responsible?
Primary visual cortex
What lobe is the Primary Visual Cortex (Brodmann’s area 17) located?
Occipital Lobe
What is within grey matter?
Neurons
What is within the white matter?
Axons
What causes cortical dysplasia?
Either a mutation during in-utero development (congenital) or injury/infection during birth
How many layers of cortical lamination are typical?
6
How will cortical dysplasia appear on imaging?
Less dense areas within the white matter
What layer of the cortical lamination is responsible for receiving information from the thalamus?
Layer 4 (Stellate cells)
What layer of the cortical lamination layers are responsible for output of information?
Layer 5 (Dendrites) and 6 (Descending axon)
What is the organization of the somatosensory cortex?
Cortical Columnar Organization
How many units can your working memory hold at one time?
about 7, why phone numbers are 7 numbers long (executive function)
How does the orbitofrontal cortex associate an experience of fear?
It associates the subjective experience of fear with the “context” of the other information present even if it wasn’t directly associated with the fear provoking sound, object etc.
Workplace example
In regards to lateralization (hemispheric specialization) which side does language primarily lateralize too?
The left hemisphere
What is Broca’s aphasia?
impairment in speech production with spared comprehension
speaking, writing, and singling impaired
What is Wernicke’s aphasia?
Impairment in speech comprehension with spared production (word salad- sentences have no meaning)
What causes Conduction (associative) aphasia?
Caused by severing the arcuate fasciculus (the connection between Broca’s and Wernicke’s area)
What structures are damaged and therefore leading to the confusion and disorientation seen in Wernicke-Korsakoff’s syndrome?
Diancephalon damage (hypothalamus and thalamus)
What structure is responsible for developing our learned fear emotion?
Amygdala
What is Kluver-Bucy syndrome?
Happens when there is bilateral damage to the temporal lobe or removal of the amygdala - loss of fear, increased/inappropriate sexual arousal
Researched in Monkey’s (removal of amygdala)
What is Urbach-Wiethe disease?
Calcification of the medial temporal lobe - patient will demonstrate the associated symptoms of Klover-Bucy syndrome and have a loss of fear of social cues (emotional memory), doesn’t recognize emotions on faces
What structure does Alzheimer’s disease effect?
Hippocampus
