Central nervous system Flashcards
Acute-hypoxic injury - causing soma shrinking, pyknosis, eosinophilia “Red neurons” are all associated with what kind of neuronal injury
irreversible
Swelling of soma, peripheral dispersal of Nissl substance, and decreased axonal transport are all associated with what kind of neuronal injury
reversible
True or false; following neuronal injury, CNS fibrosis (gliosis) from astrocytes
true
true or false; oligodendrocytes produce myelin in CNS
true
What is considered the “macrophage” of CNS
Microglia
Is there ever a time when blood in the brain is normal?
no - if blood is in brain when contacts neurons = neuron death - BBB usually stops this from happening
Where would you expect to find ependymal cells? What is a common infection?
They line ventricles and spinal cord
Common infection would be cytomegalovirus (CMV)
What is the main function of choroid plexus?
produce CSF
What is the common histological finding in rabies? What about CMV (cytomegalovirus)?
Rabies - Negri body
CMV - Owl’s eye
Why do dogs with rabies “foam at mouth”
On top of causing neurological effects (aggression/delusions) dogs “foam at mouth” because virus effects swallowing reflex - more like drooling than foaming
What neurodegenerative disease causes “Lewy bodies” histologically? Which one causes neurofibrillary tangles and beta-amyloid plaques?
Lewy body - Parkinson disease
beta-amyloid - Alzheimer’s
True or false; Severe trauma, tumors, infections or inflammation are all examples of possible causes of extracellular edema
true
True or false; Cytotoxic (neuronal/glial membrane injuries) in brain would cause intracellular edema
true
What is hydrocephalus? What phenotypic change is associated with it?
Increased volume of CSF in ventricles in children
Causes very large skull (increased pressure coupled with non-ossified sutures)
True or false; hydrocephalus (increased CSF volume within ventricles) is MC caused by overproduction of CSF
false; overproduction is rare - typically caused by disturbed flow/reabsorption
What is the main difference between hydrocephalus in a patient 2 years old
< 2 years old - cranial enlargement
> 2 years old - increased intercranial pressure - ventricular enlargement
How can a positive feedback loop start in a brain herniation?
Increased intercranial pressure (hemorrhage, pus, tumor, edema) this causes compression on neurons and vessels - decreasing blood supply - leading to infaction - necrosis - inflammation- furthering swelling
Of the 3 kinds of brain herniation: Subfalcine (cingulate), Transtentorial (uncinate), and Tonsillar - which is MC
Subfalcine (cingulate) - displaced cingulate gyrus under falx cerebri
A brain herniation displaced temporal lobe - under anterior tentorium is called what? What is the common CN effected and what does it cause?
Transtentorial (uncinate) - CN 3 - causes “brown pupil” and causes Duret hemorrhage (flamed shaped hemorrhage in pons)
Displaced cerebellar tonsils through the Foramen magnum is describing what kind of brain herniation
tonsillar
A displaced cingulate gyrus - under the falx cerebri is describing the MC brain herniation
Subfalcine (cingulate)
A Duret hemorrhage is “flamed shaped” hemorrhage associated with which kind of brain hemorrhage
Transtentorial (uncinate)
What are Arnold-Chiari malformations? Is there more than one kind?
Cerebellar tonsils pushing into foramen magnum
Yes - Type 1 and 2 -
What is the difference between type 1 and type 2 Arnold-Chiari malformations
Type 1 - MC, Milder - low-lying cerebellar tonsils - in Adults
Type 2 - Less common, more severe - small posterior fossa - in infants - misshapen midline cerebellum
What is the difference between Decorticate and Decerebrate rigidity
Decorticate - injury between cortex and red nuclei (mid brain)
Decerebrate - injury in brainstem - between red nuclei (mid brain) and vestibular nuclei
What is the difference in patient presentation between decorticate and decerebrate rigidity
Decorticate - Brachial flexion - extension of legs - internal rotation
Decerebrate - extension all 4 limbs - pronation of arms - plantar flexion
What is the 3rd leading cause of death in US
Cerebrovascular disease (CVA)
What is the MC cause of neurologic morbitity and 3rd leading cause of death in US
Cerebrovascular disease (CVA)
Strokes can be caused by 3 things : Thrombotic occlusion, Embolic occlusion, Vascular rupture. What is the difference between them?
Thrombotic (narrowing of vessel)
Ebolic ("piece of ice coming into straw")
Vascular rupture ("bent straw while getting paper off")What is scientific name for “mini-stroke”
Transient ischemic attack (TIA)
True or false; in a TIA (“mini stroke”) infarction occurs
false
of the total cardiac output, how much does the brain receive?
15%
After a cerebral infarction, how long until you see neutrophils? Macrophages? Gliosis?
Neutrophils - 48 hours
Macrophages - 10 days
Gliosis - weeks to months
true or false; primary brain parenchymal hemorrhages are spontaneous and non-traumatic
true
of the total cardiac output, how much does the brain receive?
15%
After a cerebral infarction, how long until you see neutrophils? Macrophages? Gliosis?
Neutrophils - 48 hours
Macrophages - 10 days
Gliosis - weeks to months
true or false; primary brain parenchymal hemorrhages are spontaneous and non-traumatic
true
of the total cardiac output, how much does the brain receive?
15%
After a cerebral infarction, how long until you see neutrophils? Macrophages? Gliosis?
Neutrophils - 48 hours
Macrophages - 10 days
Gliosis - weeks to months
true or false; primary brain parenchymal hemorrhages are spontaneous and non-traumatic
true
