Pathoma Neurology Flashcards
(164 cards)
1
Q
PNS develops from?
A
neural crest
2
Q
CNS develops from?
A
wall of neural tube
3
Q
ventricles & spinal canal develop from?
A
lumen of neural tube
4
Q
neural tube defects?
A
lack of folate PRIOR to conception
detected by elevated AFP in amniotic fluid or maternal blood
5
Q
frog like appearance of fetus
A
anencephaly; lacks swallowing centers in brain - polyhydramnios
6
Q
meningocele vs meningomyeleocele?
A
meningocele = meninges alone coming out; meningomyeleocele = meninges + spinal cord
7
Q
what is spina bifida?
A
failure of posterior vertebral arch to close leading to vertebral defect, with cystic protrusion of underlying tissue through the defect
8
Q
how does spina bifida occulta present?
A
dimple or patch of hair over vertebral defect
9
Q
what is cerebral aqueduct stenosis?
A
congenital stenosis of the channel that drains cerebrospinal fluid from 3rd to 4th ventricle –> hydrocephalus
10
Q
Where is CSF produced?
A
choroid plexus lining the ventricles
11
Q
describe the flow of the CSF
A
from lateral ventricles to the 3rd ventricle via interventricular foramen of monro then to the 4th ventricle via cerebral aqueduct. The CSF then goes into the subarachnoid space via foramina of Magendie and Luschka
12
Q
How does cerebral aqueduct stenosis present?
A
enlargin head circumferance due to the dilation of the ventricles (cerebral sutures are not fused)
13
Q
massively dilated 4th ventricle w/absent cerebellum?
A
Dandy-Walker malformation; failure to develop cerebellar vermis
14
Q
congenital extension of cerebellar tonsils thru foramen magnum?
A
Arnold-Chiari malformation; associated: hydrocephalus, meningimyeleocele and syringomyelia
15
Q
what is syringomyelia
A
cystic dilation of the spinal cord from trauma or Arnold-Chiari leading to C8-T1 damage.
16
Q
How does syringomyelia present?
A
loss of pain & temperature sensation in UE, sparing of position & fine touch due to involvement of anterior white commissure of spinothalamic tract with dorsal column sparing
17
Q
syrinx expansion in syringomyelia can lead to what other symptoms?
A
can damage anterior horn (motor) & lateral horn (sympathetic to face, Horner’s syndrome)
18
Q
sx of lower motor neuron dysfxn
A
anterior horn dysfxn; poliomyelitis, Werdnig-Hoffman dz
19
Q
Poliomyelitis is the result of what neuro defects?
A
anterior horn; LMN defects
20
Q
what are lower motor neuron signs?
A
flaccid paralysis with muscle atrophy, fsciculations, weakness with decreased muscle tone, impaired reflexes and negative Babinski
21
Q
Werdnig-Hoffman has what defects?
A
inherited degeneration of anterior horn motor neurons, autosomal recessive; floppy baby”, death w/in a few years after birth”
22
Q
ALS has what defects?
A
UMN & LMN degeneration
23
Q
patient presenting with motor weakness in hands - what differentiates between ALS vs syringomyelia?
A
ALS is motor only; syringomyelia would also have pain/temp deficits
24
Q
what are the upper motor neuron signs?
A
spastic paralysis with hyperreflexia, increased motor tone and positive Babinski due to damage to the lateral corticospinal tract
25
what is defect in familial ALS?
zinc-copper superoxide dismutase mutation (important mechnaism of removing free radicals)
26
difficulty walking, loss of vibratory sense & proprioception, mm weakness in LE, loss of DTR?
Friedrich's ataxia; degenerative disorder of cerebellum
27
what are characteristics of Friedrich's ataxia?
degenerative disorder of cerebellum & spinal cord tracts; autosomal recessive, trinuc GAA repeat in frataxin gene; HYPERTROPHIC cardiomyopathy
28
what gene is defective in Friedrich Ataxia? What does it do?
frataxin gene, necessary for mitochondrial iron regulation; increase risk of free radicals
29
what is inflamed in meningitis?
leptomeninges - the pia & arachnoid matter
30
MCC meningitis in neonates?
GBS, E coli, Listeria monocytogenes
31
MCC meningitis in children & teenagers?
Neisseria meningitidis; enters thru nasopharynx
32
MCC meningitis in adults & elderly?
Strep pneumo
33
MCC meningitis in unvaccinated?
Haemophilus influenza
34
MCC viral meningitis?
Coxsackievirus
35
Meningitis in immunocompromised?
think of fungi
36
Meningitis presentation
headache, nichal rigidity, fever; photophobia, vomiting and altered mental status may present
37
doing LP what layers are pierced?
Dura & Arachnoid, NOT Pia between L4 and L5
38
LP w/lymphocytes & low CSF glucose?
Fungal
39
LP w/lymphcytes & nl CSF glucose
Viral
40
LP w/neutrophils & low glucose
Bacterial; positive gram stain & culture
41
death from meningitis occurs because of:
herniation secondary to cerebral edema; seen w/bacterial b/c of pus production, etc
42
hydrocephalus, hearing loss, & seizures w/meningitis are from?
the healing process, fibrosis; primarily seen w/bacterial meningitis
43
majority of Cerebrovascular Dz?
ischemic (85%); hemorrhagic is ~15%
44
type of CVA caused by hypoglycemia?
global ischemia; see w/repeated episodes (insulinoma)
45
what are the major etiologies of global cerebral ischemia?
low perfusion, acute decrease in blood flow, chronic hypoxia, repeated hypoglycemia
46
highly vulnerable areas of the brain?
pyramidal layers of the cortex; layers 3, 5, & 6 leading to laminar necrosis
pyramidal neurons of hippocampus
purkinje layer of cerebellum
47
cortical lamenar necrosis
lines of necrosis; pyramidal layers 3, 5, & 6
48
focal neural deficits < 24 hours?
TIA
49
what causes a thrombotic stroke?
rupture of atherosclerotic plaque
50
where does atherosclerosis usually develop?
branch points, bifurcation of internal carotid and middle cerebral artery
51
what is the MC source of emboli in an embolic stroke?
left side of heart, atrial fibrillation
52
pale vs hemorrhagic necrosis following ischemia?
```
pale = thrombotic (ruptured plaque, prevents successful lysis, periphery of cortex);
hemorrhagic = embolic (embolus comes in, causes ischemia, is lysed, periphery of cortex)
```
53
MC site of embolic stroke?
middle cerebral artery
54
what is a lacunar stroke?
results from hyaline arteriolosclerosis; this occurs w/HTN or diabetes
55
MC site of lacunar stroke?
lenticulostriate vessels (feeding deep structures of the brain) - lake like areas of infarction on gross inspection
56
order of histologic appearance following ischemic stroke?
```
eosinophillic change: red neurons (~12 hours)
coagulative necrosis (24hrs): PMNs (1-3days), microglial cells (4-7days), granulation tissue (weeks 2-3)
--> fluid-filled cystic space surrounded by gliosis (reactive astrocytes)
```
57
what is intracebral hemorrhage? What is it caused by? Complication of? MC site?
bleeding into brain parenchyma; due to ruptured Charco-Bouchard microaneurysms of lenticulostriate vessels; complication of HTN; basal ganglia MC site
58
How does an intracerebral hemorrhage present?
severe headach, nausea, vomiting coma
59
Charcot-Bouchard aneurysms?
caused by hyaline arteriosclerosis; can result in intracerebral hemorrhagic stroke
60
see a bleed on bottom of the brain?
subarrachnoid hemorrhage; really only cause
61
How does subarrachnoide hemorrhage present?
worst headach of my life with nuchal rigidity
62
What do you see on lumbar puncture with subarachnoid hemorrhages?
xanthochromia (yellow hue due to bilirubin breakdown)
63
MCC subarachnoid hemorrhage?
berry aneurysms, other cuases are AV malformation and anticoagulated state
64
MC location of berry aneurysms? Assocaited with?
cause subarachnoid hemorrhage; MC located in anterior circle of willis, specifically anterior communciating artery; associated w/marfan & ADPKD
65
histology of berry aneurysm?
thin walled, lack media layer
66
trauma w/lens shape lesion on CT?
epidural hemotoma
67
cause of epidural hematoma?
fractured temporal bone --> rupture of middle meningeal artery --> bleeding separates dura from the skull
68
cause & pathophys of subdural hematoma?
trauma; tearing of BRIDGING veins between dura & arachnoid; increased risk w/atrophy (b/c brain has shrunken back)
69
CT appearance of subdural hematoma
crescent shaped
70
clinical course of subdural hematoma?
progressive neurologic signs; herniation is lethal complication
71
sub-falcian herniation?
herniation of cingulate gyrus under falx cerebria (vertical); compress anterior cerebral artery --> infarction
72
tonsillar herniation?
cerebellum thru foramen magnum; compresses brain stem --> cardiopulmonary arrest
73
uncal herniation?
displacement of temporal lobe uncus under the tentorium derebelli leading to compression of CN III (down and out, dilated pupil), compression of PCA, rupture of paramedian artery --> Duret (brainstem) hemorrhage
74
deficiency of arylsulfatase?
metachromatic leukodystrophy; can't degrade myelin (which must be done regularly), accumulates in lysosomes of oligodendrocytes
75
Krabbe disease?
leukodystrophy; deficiency of galactocerebroside beta-galactosidase; galactocerebroside accumulates in macrophages
76
adrenoleukodystrophy?
impaired addition of CoA to long chain FA; FA accumulates damaging adrenal gland & white matter (X linked recessive)
77
what cells are destroyed in MS? What is genetic susceptibility? Environmental trigger?
oligodendrocytes; HLA-DR2; more common in regions away from equator
78
Multiple Sclerosis symptoms
Multiple Sclerosis; scanning speech - resembles drunk, brainstem; Blurred vision 1 eye - optic nerve; internuclear ophthalmoplegia - MLF, hemiparesis, lower extremity loss of sensation
79
dx of MS?
MRI - plaques; LP - increased lymphocytes, increased Ig w/oligoclonal IgG bands, myelin basic protein
80
oligoclonal IgG bands in CSF?
Multiple Sclerosis
81
gross inspection of MS brain?
grey areas in white matter (demyelinating)
82
tx MS?
acute - high dose steroids; slow progression - IFN-beta; immune suppression, natalizumab
baclofen for spasticity
catheterization, musc agonists for neurogenic bladder
opioids for pain
83
subacute sclerosing panencephalitis?
measles infection of the brain (demyelinating); slow progressing, persistent - progressive, debilitating, leading to death; infection in infancy, signs arise years later
84
viral inclusions w/in neurons (gray matter) & oligodendrocytes (white matter)?
measels; SSPE (subacute sclerosing panencephalitis)
85
immunocompromised pt w/rapidly progressing neurological signs?
Progressive Multifocal Leukoencephalopathy (demyelinating); reactivation of latent JC virus; leads to death
86
rapid IV correction of hyponatremia?
Central Pontine Myelinolysis; focal demyelination of pons; typically alcoholic / severely malnourished
87
locked in syndrome?
only eyes can move; classic for Central Pontine Myelinolysis
88
broadly, in neurodegenerative disorders where is the degeneration? Sx?
in the cortex (gray matter outside the white) - dementia; in the deeper brain, by ventricles (basal ganglia) --> movement problems
89
MCC dementia?
Alzheimer's
90
clinical features of alzheimer's
slow onset memory loss
loss of learned motor skills and language
changes in behavior and personality
mute and bedridden
91
genetic associations with alzheimer's
epsilon4 allele of APOE increases risk but epsilon2 decreases risk
familial cases: presenilin 1 and presenilin 2 mutations
92
protein pathophys of alzheimer's?
Amyloid Precursor Protein on chromosome 21; normally broken down to alpha; in alzheimer's broken down to A-beta amyloid which cannot be broken down --> deposited in the brain
93
what are neuritic plaques?
extracellular core comprised of Abeta amyloid with entangled neuritic processes
94
what are neurofibrillary tangles?
intracellular aggregates of fibers composed of hyperphosphorylated tau protein which is a microtubule associated protein
95
are there any focal neurlogic deficits with Alzheimer's?
No (no pillrolling tremor; no chorea, etc) (not early)
96
forms of alzheimer's? risk factors?
Sporadic form - age, increased with E4 & decreased with E2; Early form - younger patients, familial (presenilin 1) & down syndrome - APP on C21 x3
97
what trisomy has increased risk of alzheimer's? why?
Down's, APP (amyloid precursor protein) is on chromosome 21; most pts get AD by 40 yo
98
what is familial cause of alzheimer's?
mutation in presenilin 1
99
diffuse cerebral atrophy?
Alzheimer's; narrowing of gyri, widening of sulci; get hydrocephalus ex vacuo (dilation of ventricles)
100
histologic findings of alzheimer's?
neuritic plaques; a-beta plaques (extracellular) w/entrapped neuritic processes; & neurofibrrillary tangles (flame shaped edge") in the cytoplasm, tau (microtubule associated) protein is hyperphosphorylated"
101
where is A-beta plaque found?
extracellularly; amyloid is always extracellular
102
vascular complication of alzheimers?
cereberal amyloid angiopathy; amyloid plaques can deposit around arteries, weaken them, predispose to hemorrhage
103
characteristic of neurofibrillary tangles in alzheimer's?
hyperphosphorylated tau protein, intracellular
104
2nd MCC dementia? Pathophys?
Vascular Dementia; multifocal infarction & injury caused by HTN, atherosclerosis, or vasculitis
105
degenerative dz of frontal & temporal cortex; sparing parietal & occipital lobes?
Pick Disease (picks frontal & temporal)
106
dementia, & early behavioral & language symptoms?
Pick Disease; frontal - behavior; language - temporal
107
ROUND aggregates of tau proteins?
Pick disease (recall alzhemier's has the triangle shaped flames")"
108
effect of Dopamine on cortex thru Basal ganglia?
Increased movement; D1 - excitatory stimulus; D2 - disinhibition
109
Parkinson's disease has loss of what?
dopaminergic neurons in substantia nigra pars compacta (basal ganglia)
110
illicit drug contaminant that can result in Parkinson's?
MPTP
111
key risk factor in Parkinson's?
aging; don't know the exact cause though
112
clinical features of Parkinson's?
TRAP - tremor, rigidity, akinesia/bradykinesia, postural instability/shuffling gate
113
histological features of Parkinson's
loss of pigmented neurons in substantia nigra and round, eosinophillic inclusions of alpha-synuclein (Lewy bodies) in affected neurons
114
lewy body? Composed of?
round eosinophilic inclusions in pars compacta of substantia nigra; Parkinson's; composed of alpha-synuclein
115
does Parkinsons's have dementia?
not early (late)
116
lewy body dementia - lewy bodies are located where? Sx?
cortical lewy bodies; early onset dementia w/hallucinations & parkinson like features
117
loss of gabergic neurons in caudate nucleus?
(basal ganglia) Huntington's - chorea; lose inhibitory hold on cortex - random firing of system
118
grey matter structure indenting lateral ventricle?
caudate nucleus
119
striatum is made of:
caudate + putamen, seperated by internal capsule; caudate is by lateral ventricle, putatmen is inferolateral
120
gross inspection of huntingtons?
coronal section; loss of caudate nucleus (lateral ventricles enlarge b/c of ths)
121
when does anticipation occur w/Huntington's?
during spermatogenesis
122
slow, involuntary snake-like" movement of fingers?"
Athetosis; Huntington's
123
urinary incontinence, gait instability, & dementia
classic triad of Normal Pressure Hydrocephalus; results from stretching of Corona Radiata w/hydrocephalus; Wet, Wacky, & Wobbly""
124
how to tx Normal Pressure Hydrocephalus?
ventriculoperitoneal shunt (CSF to peritoneum); notably, NPH improves w/lumbar puncture
125
why is there increased CSF in nl pressure hydrocephalus?
decreased absorption of CSF into arachnoid granulations, unknown reason
126
stretching of corona radiata?
wet, wobbly, wacky" - urinary incontinence, gait instability, dementia; see in normal pressure hydrocephalus"
127
spongiform encephalopathy?
Prion dz; PrPc --> PrPsc; accumulates & creates vacuations in brain
128
what form is pathologic prion protein in?
beta-pleated; converted from alpha form
129
intracellular vacuoles?
spongiform encephalopathy; accumulation of pathologic proteins in vacuoles causing damage
130
MCC spongiform encephalopathy?
CJD; usually sporadic
131
EEG of CJD?
spike waves on EEG
132
course of CJD?
rapid dementia (weeks to months); death w/in year; can get ataxia & startle myoclonus
133
insomnia & exaggerated startle response?
familial fatal insomnia; inherited form of spongiform encephalopathy
134
MCC metastasis TO the brain?
Lung, Breast, Kidney cancer
135
Metastasis or primary tumors of CNS more common?
equal, 50/50
136
will primary CNS tumors metastasize?
No, not outside CNS (usually); are locally destructive
137
MCC CNS tumor in adults? Type of cell?
Glioblastoma multiforma; astrocyte derived (glial cell = GFAP positive)
138
where do CNS tumors in adults usually occur? Kids?
adults - supratentorial; kids - infratentorial
139
most common tumors in children
pilocytic astrocytoma, ependymoma, and medulloblastoma
140
tumor crossing midline of brain?
butterfly glioma, Glioblastoma Multiforma; MCC adult CNS tumor; derived from astrocytes"
141
pseudopalisading necrosis"? Other histological feature?"
histological feature of GBM; central area of necrosis w/living cells sort of" lining up around (pseudopalisading); endothelial cell proliferation; derives from glial cell (astrocyte)"
142
what is the intermediate filament present w/in glial cells? Why care?
GFAP - marker for type of tumor - eg GBM
143
MCC benign tumor in adults?
Meningioma; Females > Males (note: cell expresses estrogen receptor)
144
seizures in female woman w/round mass on imaging?
Meningioma; tumor compresses but does NOT invade the cortex
145
whorled appearance" w/psammoma bodies on histology?"
Meningioma
146
tumor of pt presenting w/tinnitus/loss of hearing - type? Marker? Association?
Schwannoma - benign; inovles CN or spinal nerves, esp CN 8 at cerebellopontine angle; S100 positive; bilateral seen in NF2
147
bilateral acoustic schwanoma?
NF2
148
calcified tumor in the white matter of frontal lobe?
Oligodendroglioma, malignant, present w/ seizures
149
fried egg appearance"?"
classic for oligodendroglioma or MS
150
cystic brain lesion w/nodule growing on wall?
pilocytic astrocytoma (piloCYSTic)
151
astrocytes w/thick eosinophilic processes?
pilocytic astrocytoma; Rosenthaal fibers; children
152
biopsy of pilocytic astrocytoma shows
rosenthaal fibers (thick eosinophillic processes of astrocytes and eosinophillic granular bodies
153
S100?
Schwannoma (benign)
154
GFAP positive?
glial derived - pilocytic astrocytoma; GBM
155
medulloblastoma?
children; derived from granular cells of cerebellum; small round blue cells & Homer-Wright rosettes; poor prognosis, spreads via CSF
156
tumor deriving from granular cells of cerebellum?
Medullablastoma (children, poor prognosis)
157
small, round blue cells & Homer-wright rosettes?
medulloblastoma (children, poor prognosis)
158
how does medulloblastoma spread?
via CSF, 4th ventricle --> spinal cord
159
drop metastasis" of CNS lesion to spinal cord?"
Medullablastoma (children, poor prognosis)
160
Ependymoma?
malignant, usually children, ependymal cells lining 4th ventricle; presents w/hydrocephalus
161
perivascular pseudorosette?
ependymoma; blue cells lining up around a vessel
162
bitemporal hemianopsia in child or young adult?
supratentorial mass --> optic chiasm compression; Craniopharyngioma, arising from epithelial remnants of Rathke's pouch
163
where do craniopharyngioma's come from?
epithelial remnants of Rathke's pouch (floor of mouth); seen in children, supratentorial mass
164
craniopharyngioma on imaging? After resection?
calcifications on imaging; tends to recur after resection
