Neuropathology Flashcards
(185 cards)
1
Q
what do glial cells do
A
regulate homeostasis
provide support and protection to neurons
2
Q
what does an astrocyte do
A
maintain blood barrier
3
Q
what does an oligodendrocyte do
A
myeline CNS axons
4
Q
what does a microglial cell do
A
act as a phagocyte
5
Q
what do ependymal cells do
A
produce CSF
6
Q
what are the 5 changes seen in acute neural injury (red neurons)
A
1.) shrinkage of cell body
2.) pyknosis of nucleus
3.) lack of nucleolus
4.) loss of Nissl substance
5.) eosinophilia of cytoplasm
7
Q
what is the best indicator of neuronal injury
A
reactive glial cell changes
8
Q
what is the most important histopathologic marker of CNS injury
A
gliosis
9
Q
what is gliosis
A
injury of astrocytes that leads to hypertrophy and hyperplasia
10
Q
what are the two hallmarks of gliosis
A
Rosenthal fibers and corpora amylacea
11
Q
what is corpora amylacea
A
brain sand - polyglucosan aggregates from waste products
12
Q
what are the 4 steps of microglia response to injury
A
1.) proliferate
2.) formation of elongated nuclei (rods)
3.) formation of aggregates around tissue necrosis
4.) congregation around cell bodies of dying neurons
13
Q
what can be seen histologically in oligodendrocyte injury
A
nuclear viral inclusions or cytoplasmic inclusions
14
Q
what are ependymal granulations
A
small irregularities on the ventricular surfaces caused by astrocyte proliferation
15
Q
which condition can cause ependymal injury with viral inclusions
A
cytomegalovirus (CMV)
16
Q
what are the three main causes of increased intracranial pressure
A
1.) brain edema
2.) hydrocephalus (increased CSF)
3.) expanding masses
17
Q
what are the two types of cerebral edema
A
1.) vasogenic edema
2.) cytotoxic edema
18
Q
what is vasogenic edema
A
blood brain barrier disruption causes increase in extracellular fluid
only affects white matter
19
Q
what is cytotoxic edema
A
injury to cells causes secondary increase in intraceullar fluid
common in cases of obesity and diabetes
affects white and gray matter
20
Q
what are the three changes associated with generalized cerebral edema
A
1.) flattening of gyri
2.) narrowing of sulci
3.) compression of ventricles
21
Q
what is the main change associated with interstitial cerebral edema
A
lateral ventricle compression
22
Q
which structure generates the CSF
A
choroid plexus
23
Q
what is hydrocephalus
A
accumulation of successive CSF in the ventricular system of the brain
most commonly cause by impaired flow and resorption of CSF
24
Q
what is hydrocephalus ex vacuo
A
compensatory increase in ventricular volume secondary to loss of brain parenchyma
ex. Alzheimer’s
25
what is a subfalcine herniation
asymmetric expansion of cerebral hemisphere that displaces the cingulate gyrus under the falx
can cause compression of anterior cerebral artery
26
what causes a red neuron
lack of oxygen (hypoxia)
27
what is a transtentorial herniation
compression of medial temporal lobe against free margin of tentorium
can cause compression of third cranial nerve (oculomotor) or the posterior cerebral artery which would affect the eyes
28
what is a tonsillar herniation
displacement of cerebellar tonsils through the foramen magnum
can cause brainstem compression - most deadly
29
what are duret hemorrhages
secondary hemorrhagic lesions in the midbrain and pons due to progression herniation
30
what is the most common form of CNS malformation
neural tube defects
31
the most common neural tube defect involves what
the spinal cord
32
what is a well-known risk factor for a neural tube defect
folate deficiency
33
what is the most common type of neural tube defect
spina bifida occulta
34
what is a meningoencephalocele
neural tube defect where a large portion of the occipitoparietal brain tissue protrudes through the posterior fontanel
35
a meningoencephalocele is associated with which condition
Meckel-Gruber syndrome
36
what is iniencephaly
lack of occipital bone and cervicothoracic spinal fusion
37
what is anencephaly
absence of scalp, cranium, and most of brain
38
what is craniorachischisis
combination of ancenphaly and boney spinal defect
39
what are the three main causes of macrocephaly and microcephaly
1.) chromosome abnormalities
2.) fetal alcohol syndrome
3.) HIV infection in utero
40
what is the main consequence of agenesis of the corpus callousum
prevents both sides of brain from communicating
41
which three malformations are associated with posterior fossa anomalies (malformations of brainstem and cerebellum)
1.) Arnold-Chiari
2.) Chiari Type 1
3.) Dandy-Walker
42
what is Arnold-Chiari (type 2) malformation
abnormally small posterior fossa and misshapen midline extensions of vermis through foramen magnum
causes hydrocephalus and lumbar myelomeningocele
43
Arnold-Chiari (type 2) malformation is associated with what
spina bifida
44
what is Chiari type 1 malformation
low-lying cerebellar tonsils that extent into the vertebral canal
45
what is Dandy-Walker malformation
enlargement of posterior fossa leads to absence of cerebellar vermis and replacement by midline cyst
46
what Cerebral Palsy
neurologic motor deficit due to injury in prenatal and perinatal periods of development
47
what three things can be seen in Cerebral Palsy
1.) hemorrhage
2.) periventricular leukomalacia
3.) multi cystic encephalopathy
48
what is periventricular leukomalacia
infarcts in the periventricular white matter seen in Cerebral Palsy
49
what is multicystic encephalopathy
large, destructive cystic lesions in the brain caused by ischemic damage
seen in Cerebral Palsy
50
what is a displaced skull fracture
one that extends beyond the thickness of the cranium
51
conscious falls tend to affect which area of the skull
occipital fractures
52
unconscious falls tend to affect which area of the skull
frontal fractures
53
what is a diastatic fracture
skull fracture whose line transverses one or more suture of the skull and lead to its widening
most common in infants an young children
54
contusions and lacerations of the brain are most common in which two regions
1.) frontal
2.) temporal
55
what is a plaque jaune
remote contusion of the brain which is a yellow color
56
what is an epidural hematoma
pooling of arterial blood between the dura and periosteum
57
what is a subdural hematoma
pooling of venous blood between the dura and brain parenchyma
58
what is the gross appearance of an acute subdural hematoma
collection of freshly clotted blood along the brain's surface that doesn't go down into the sulci
59
what are the three steps to the breakdown of a subdural hematoma
1.) lysis of clot (1 week)
2.) growth of fibroblasts into hematoma (2 weeks)
3.) development of hyalinized connective tissue (1-3 months)
60
cord injury at and below the level of the thoracic vertebrae often causes what
paraplegia
61
cord injury at the level of the cervical vertebrae often causes what
quadriplegia
62
cervical lesions above C4 can often causes what
respiratory compromise and paralysis of the diaphragm
63
what is a stroke and what are the two types
sudden interruption of blood flow to the brain
types: ischemic and hemorrhagic
64
what is an ischemic stroke
hypoxia, ischemia, and infarction caused by impairment of blood supply
65
what is the most common cause of an ischemic stroke
embolism
66
which two things can cause a hemorrhagic stroke
1.) hypertension
2.) vascular anomalies like aneurysms
67
what is a hemorrhagic stroke
rupture of blood vessel leads to hemorrhage
68
the brain receives about ____% of the body's resting cardiac output
15%
69
what are the three survival factors in regards to a cerebrovascular brain injury
1.) collateral circulation
2.) duration of ischemia
3.) magnitude of event and timeliness of onset
70
what is global cerebral ischemia (diffuse ischemic/hypoxic encephalopathy)
reduction of cerebral perfusion caused by cardiac arrest, shock, or severe hypotension
71
which brain cell, neurons or glial cells, are most sensitive to hypoxia
neurons
72
which three types of neurons are most sensitive to hypoxia
1.) pyramidal cells of hippocampus
2.) purkinje cells of cerebral cortex
3.) pyramidal neurons in cerebral cortex
73
which area of the brain is at most risk for watershed infarct
area between anterior and middle cerebral artery
74
what is the border (watershed) zone
regions of brain/spinal cord most distal to the anterior blood supply
damage here produces sickle-shaped band of necrosis
75
the major source of collateral flow in the brain is what
the circle of Willis
76
which three locations have the least amount of collateral flow within the brain
1.) thalamus
2.) basal ganglia
3.) deep white matter
77
which artery is most at risk for a cerebral infarct caused by embolus
middle cerebral artery
78
what are the three main causes of a paradoxical emboli
1.) cardiac anomalies in children
2.) cardiac surgery
3.) tumor, fat, or air
79
fat embolism syndrome is a common occurrence after what
after fractures and trauma to the bone marrow
80
what are the three most common locations of a cerebral infarct caused by thrombus
1.) bifurcation of carotid arteries
2.) origin of middle cerebral artery
3.) end of basilar artery
81
cerebral infarct caused by thrombus is often associated with which two conditions
1.) hypertension
2.) diabetes
82
what are the two main causes of a cerebral infarct caused by inflammation of blood vessels
1.) infectious vasculitis
2.) non-infectious vasculitis
83
what are the two main causes of infectious vasculitis
1.) syphilis
2.) TB
84
what are the three main causes of non-infectious vasculitis
1.) polyarteritis nodosa
2.) primary angitis of the CNS
3.) granulomatous angitis
85
what are three causes of cerebral infarcts caused by "other" things
1.) hypercoagulation states
2.) dissecting aneurysm of arteries in the neck
3.) drug abuse
86
which two conditions can cause lacunar infarcts
1.) diabetes
2.) hypertension
87
what is seen histologically in the beginning stages of acute ischemic injury of the brain
diffuse eosinophilia of shrinking neurons
88
what is seen histologically 10 days after an acute cerebral infarct
foamy macrophages and reactive gliosis with neovascularization
89
what are Charcot-Bouchard microaneurysms
minute aneurysms seen in an intracranial hemorrhage
90
what is the most common cause of a subarachnoid hemorrhage
rupture of a berry aneurysm in a cerebral artery
91
what is the most common type of intracranial aneurysm
saccular
92
what is the most common location for a saccular aneurysms
anterior communication artery
93
which two things increase your risk for a saccular aneurysms
1.) smoking
2.) hypertension
94
what are the four main types of vascular malformations
1.) arteriovenous
2.) cavernous
3.) capillary telangiectasias
4.) venous angiomas
95
what is an arteriovenous malformation
tangled network of vasculature with arteriovenous shunting
96
what is the most common type of significant venous malformation
arteriovenous
97
what is the most common site of an arterivenous malformation
middle cerebral artery
98
what is a cavernous malformation
tightly packed, low flow vessels not associated with arteriovenous shunting
99
what are the three most common locations for a cavernous malformation
1.) cerebellum
2.) pons
3.) subcortical region
100
what is capillary telangiectasis
microscopic dilated, thin walled vascular channels within normal brain parenchyma
101
what is the most common location for capillary telangiectasis
pons
102
what is the most common spread type of a CNS infection
hematogenous
103
what are the four spread pathways of CNS infections
1.) hematogenous
2.) retrograde venous
3.) direct implantation
4.) local extension
104
what is retrograde venous spread
spread via anastomoses with veins of the face
105
what is direct implantation spread
microorganisms gain access through traumatic opening or congenital malformation
106
what causes acute pyogenic meningitis
bacterial infection
107
what cases aseptic meningitis
viral infection
108
what causes chronic meningitis
TB, spirochete, or cryptococcal infections
109
what will an aseptic meningitis spinal tap reveal
high lymphocyte count
protein elevation
normal glucose
110
which two organisms most commonly cause acute pyogenic meningitis in neonates
1.) E. coli
2.) group B strep
111
which organism most commonly causes acute pyogenic meningitis in adolescents and young adults
neisseria
112
which two organisms most commonly cause acute pyogenic meningitis in older adults
1.) strep. pneumo
2.) listeria
113
which vaccine can lower the risk of acquiring acute pyogenic meningitis
flu vaccine
114
what are the 5 main symptoms of acute pyogenic meningitis
1.) headache
2.) fever
3.) photophobia
4.) neck stiffness
5.) irritability
115
which syndrome is associated with acute pyogenic meningitis
Waterhouse-Friderichsen syndrome
116
what are the two most common organisms to cause acute focal suppurative infections (brain abscesses)
strep and staph
117
what usually causes a subdural empyema
bacterial infections of skull or air sinuses like sinusitis or osteomyelitis
118
an extradural abscess is most commonly associated with which condition
osteomyelitis
119
which three organisms most commonly cause chronic bacterial meningoencephalitis
1.) TB
2.) syphilis (treponema)
3.) borrelia (Lyme disease)
120
what is the most frequent clinical presentation of meningovascular syphilis
stroke
121
what is Heubner arteritis
thickening and lymphocytic infiltration of intima seen in neurosyphilis
122
how is an aseptic case of meningitis diagnosed
through absence of bacteria in culture
123
what will a bacterial meningitis spinal tap reveal
high neutrophil count
high protein
low glucose
124
what are the two main things seen histologically in aseptic meningitis
1.) perivascular cuffs of lymphocytes
2.) microglial nodules
125
what is arthropod-borne viral meningoencephalitis
viral infections that have animal hosts and insect vectors (mosquitos and ticks)
ex. West Nile encephalitis
126
which regions of the brain are most affected by HSV-1
inferior and medial regions of temporal lobes
orbital gyri of frontal lobes
127
HSV-2 causes what in adults
meningitis
128
HSV-2 causes what in neonates
severe encephalitis
129
who is most affected by cytomegalovirus (CMV)
immunosuppressed individuals (HIV) and fetuses
130
15% of those with CMV develop what
hearing loss
131
CMV affects the brain in which three ways
1.) periventricular necrosis
2.) microcephaly
3.) periventricular calcification
132
what is poliomyelitis
nervous system involvement due to infection with the poliovirus
133
what are pathognomonic to rabies
Negri bodies - inclusions found in pyramidal neurons of hippocampus and Purkinje cells of cerebellum
134
what are the three neuropathologic effects seen in HIV with antiviral therapy
1.) aseptic meningitis
2.) mild lymphocytic meningitis
3.) HIV encephalitis
135
which two things are common to see histologically in HIV cases
1.) microglial nodule
2.) multinucleated giant cell
136
what causes progressive multifocal leukoencephalopathy encephalitis
JC polyomavirus
137
what is progressive multifocal leukoencephalopathy encephalitis
JC polyomavirus infection of oligodendrocytes causes demyelination
138
which fungal infection is common in those with AIDS
cryptofoccus neoformans
139
fungal infections most often cause which three forms of CNS injury
1.) chronic meningitis
2.) vasculitis
3.) parenchymal invasion
140
what are two examples of protozoal diseases that can affect the nervous system
1.) malaria
2.) toxoplasmosis
141
what are two examples of Rickettsial infections that can affect the nervous system
1.) typhus
2.) Rocky Mountain spotted fever
142
what are two examples of Metazoal disease that can affect the nervous system
1.) cysticercosis
2.) echinococcosis
143
which four types of pathologic processes can result in loss of myelin
1.) immune-mediated
2.) viral
3.) drug
4.) inherited disorders
144
what is the most common demyelinating disorder
multiple sclerosis
145
what is multiple sclerosis
autoimmune demyelinating disorder that mostly affects the myelin sheath and white matter
146
CSF tap of multiple sclerosis would show which two things
1.) mildly elevated protein
2.) elevated IgG levels
147
which stain is used to diagnose multiple sclerosis
Luxol fast blue periodic acid-Schiff stain
148
what is the pathologic process of neurodegenerative diseases
accumulation of protein aggregates (proteinopathy)
149
what is a prion
type of abnormally formed cellular protein that can trigged normal proteins in the brain to fold abnormally
150
what is the most common prion disease
Creutzfeldt-Jakob disease (CJD)
151
what is seen histologically in someone with Creutzfeldt-Jakob disease (CJD)
Kuru plaques (deposits of abnormal PrP)
may have halo of spongiform change in mad cow disease variant
152
what is the most common cause of dementia in older adults
Alzheimer disease
153
what are the two key features of Alzheimer's
accumulation of Amyloid beta and tau proteins
154
what is seen grossly in an Alzheimer brain
cortical atrophy of frontal, temporal, and parietal lobes
155
what are the two key microscopic features of Alzheimer's
1.) neuritic (senile) amyloid plaques
2.) neurofibrillary tangles (contain Tau)
156
what is the main cause of Parkinson disease
loss of dopaminergic neurons from the substantia nigra
157
what is the histologic hallmark of Parkinson disease
alpha-synuclein that forms Lewy bodies and Lewy inclusions
158
what is the main cause of Huntington disease
degeneration of striatal neurons in basal ganglia
159
what is seen grossly in someone with Huntington disease
atrophy of caudate nucleus and putamen
160
what is the most common form of motor neuron disease
amyotrophic lateral sclerosis (ALS)
161
what is amyotrophic lateral sclerosis (ALS)
loss of upper and lower **motor** neurons with evidence of toxic protein accumulation
162
what is seen grossly in the brain of someone with chronic carbon monoxide poisoning
ischemic or hemorrhage necrosis in globus pallidus
demyelination in white matter that doesn't affect arcuate fibers
163
what is seen grossly in the brain of someone with ethanol poisoning (chronic alcoholism)
1.) cerebral dysfunction
2.) atrophy and loss of granule cells in vermis
164
what is the most important factor in the outcome of a patient with a CNS tumor
location of tumor
165
which lobe of the brain is most commonly affect by tumor
frontal
166
what is the most common type of primary brain tumor in adults
grade 4 glioblastoma multiforme
167
what is the most common primary glioma
astrocytoma
168
what are the two main types of astrocytomas
1.) diffusely infiltrating
2.) localized
169
what is the most common type of localized astrocytoma
pilocytic
170
what is the most common location of a diffusely infiltrating astrocytoma
cerebral hemispheres
171
which types of glial tumor has the best prognosis
oligodendroglioma
172
what is the gross appearance of an oligodendroglioma
gelatinous with cysts, focal hemorrhage, and calcification
173
what is the histologic appearance of an oligodendroglioma
anastomosing capillaries resembling chicken wire and granular chromatin
174
chicken wire appearance is associated with which condition
oligodendroglioma
175
what are the three main histologic features of a pilocytic astrocytoma
1.) hairlike processes
2.) Rosenthal fibers
3.) mulberry like granular bodies
176
which stain is used for the hairlike processes seen in a pilocytic astrocytoma
GFAP+
177
what is the microscopic feature of an ependymoma
perivascular pseudorosettes
178
what is the most common type of embryonal neoplasm of the brain
medulloblastoma within the cerebellum
179
what is the most common neoplasm in immunocompromised patients
primary CNS lymphoma
180
what is seen histologically in primary CNS lymphoma
malignant cells around vessels and necrosis
181
what is a risk factor for the development of a meningioma
radiation therapy to head and neck
182
what is the most common genetic abnormality to cause a meningioma
loss of chromosome 22
183
what is the gross appearance of a meningioma
rubbery and bosselated
184
what is seen histologically in a meningioma
psammoma bodies
185
what are the 5 most common primary metastasis sites of brain tumors
1.) lung
2.) breast
3.) skin
4.) kidney
5.) GI
