Neuro - First Aid Flashcards
1
Q
The notochord induces…
A
overlying ectoderm to differentiate into neuroectoderm and form the neural plate.
2
Q
The neural plate gives rise to…
A
the neural tube and neural crest cells.
3
Q
The notochord becomes…
A
nucleus pulposus of the intervertebral disc in adults.
4
Q
The alar plate is…
A
dorsal/sensory.
5
Q
The basal plate is…
A
ventral/motor.
6
Q
During development, forebrain/prosencephalon includes…
A
the telencephalon and diencephalon.
7
Q
Adult derivatives of the telencephalon are…
A
the cerebral hemispheres and the lateral ventricles.
8
Q
Adult deriatives of the diencephalon are..
A
the thalamus and third ventricle.
9
Q
During development the midbrain/mesencephalon includes…
A
the mesencephalon.
10
Q
Adult derivatives of the mesencephalon are…
A
the midbrain and aqueduct.
11
Q
During development, the hindbrain/rhombencephalon includes..
A
the metencephalon and the myelencephalon.
12
Q
Adult derivatives of the metencephalon are…
A
the pons, cerebellum and upper part of the 4th ventricle.
13
Q
Adult derivatives of the myelencephalon are…
A
the medulla and lower part of the 4th ventricle.
14
Q
Neuroectoderm derivatives (4)
A
- CNS neurons 2. ependymal cells 3. oligodendroglia 4. astrocytes
15
Q
Neural crest derivatives (2)
A
- PNS neurons 2. Schwann cells
16
Q
Mesoderm derivative (1)
A
Microglia (like Macrophages, derived from Mesoderm)
17
Q
If neuroporses fail to fuse in the 4th week, there is….
A
persisten connection between the amniotic cavity and spinal canal. (neural tube defects)
18
Q
Neural tube defects are associated with….
A
low folic acid intake before conception and during pregnancy.
19
Q
Labs indicative of neural tube defects
A
-increased alpha-fetoprotein (AFP) -increased AChE in amniotic fluid
20
Q
Spina bifida occulta is due to…
A
failure of the bony spinal canal to close but there is no structural herniation. The dura is intact.
21
Q
Spina bifida occulta is associated with…
A
a tuft of hair or skin dimple at the level of bony defect. (usually lower vertebral levels)
22
Q
Meningocele
A
Meninges (but not spinal cord) herniates through the spinal canal defect; normal AFP.
23
Q
Meningomyelocele
A
Meninges and spinal cord herniate through spinal canal defect.
24
Q
Anencephaly is…
A
malformation of the anterior neural tube resulting in no forebrain and an open calvarium (“frog-like” appearance).
25
Clinical findings of Anencephaly
increased AFP polyhydramnios (no swallowing center in brain)
26
Anencephaly is associated with...
maternal diabetes. Maternal folate supplementation decreases risk.
27
Holoprosencephaly is...
failure of the left and right hemispheres to separate usually during weeks 5-6.
28
Holoprosencephaly has a complex etiology that may be related to mutations in...
sonic hedgehog signaling pathway.
29
Moderate form of holoprosencephaly has...
cleft lip/palate and more severe form results in cyclopia.
30
Chiari II (Arnold-Chiari malformation) is...
significant herniation of cerebellar tonsils and vermis through the foramen magnum with aqueductal stenosis and hydrocephalus.
31
Chiari II often presents with...
lumbosacral myelomeningocele and paralysis below the defect.
32
Dandy-Walker is...
agenesis of the cerebellar vermis with cystic enlargement of the 4th ventricle.
33
Dandy-Walker is associated with...
hydrocephalus and spina bifida.
34
Syringomyelia is a...
cystic cavity within the spinal cord that typically damages the crossing anterior spinal commissural fibers.
35
Syringomyelia presents with a...
"cape-like" bilateral loss of pain and temperature sensation in the upper extremities.
36
Syringomyelia is most common at...
C8-T1.
37
Syringomyelia is associated with...
Chiari I malformation (\> 3-5 mm cerebellar tonsillar ectopia; congenital and manifests with HAs and cerebellar symptoms)
38
The anterior 2/3 of the tongue are formed by...
1st and 2nd branchial arches (thus sensation via CN V3 and taste via CNVII).
39
The posterior 1/3 of the tongue is formed by...
the 3rd and 4th branchial arches (thus sensation and taste mainly from CN IX)
40
Motor innervation to the tongue is via...
CN XII.
41
Muscles of the tongue are derived from...
occipital myotomes.
42
Neurons are...
permanent cells; they do not divide in adulthood and generally do not have a progenitor stem cell population.
43
Cell bodies and dendrites of axons can be stained via...
Nissl substance (stains RER). RER is not present in the axon.
44
If an axon is injured, it undergoes...
Wallerian degeneration which is degeneration distal to the injury and axonal retraction proximally; this allows for potential regeneration.
45
Astrocyte Functions (6)
-physical support -repair -K+ metabolism -removal of excess NT -component of BBB -glycogen fuel reserve buffer
46
In response to neural injury, astrocytes cause...
reactive gliosis.
47
Astrocyte marker
GFAP
48
Microglia features
-CNS phagocytes (scavenger cells) -not readily discernible in Nissly stains -small, irregular nuclei and little cytoplasm
49
Microglia respond to tissue damage by...
differentiating into large phagocytic cells.
50
HIV-infected microglia will...
fuse to form multinucleated giant cells in the CNS.
51
Myelin in the CNS is formed by...
oligodendrocytes. And by Schwann cells in the PNS.
52
Myelin increases both...
space constant and conduction velocity.
53
Each oligodendrocyte can....
myelinate many axons. It is the predominant glial cell in white matter.
54
On H&E, oligodendroglia have a..
"fried egg" appearance.
55
Oligodendroglia are injured in...
MS, progressive multifocal leukoencephalopathy (PML) and leukodystrophies.
56
Each Schwann cell myelinates...
only 1 PNS axon and they promote axonal regeneration.
57
Scwhann cells are destroyed in...
Guillain-Barre.
58
Acoustic neuroma is a...
type of schwannoma typically located in the internal acoustic meaturs (CN VIII).
59
If acoustic neuroma is bilateral, it is strongly associated with...
neurofibromatosis type 2.
60
Freen nerve endings description
C fibers - slow, unmyelinated Adelta fibers - fast, myelinated
61
Free nerve endings are located in the...
skin, epidermis
62
Free nerve endings sense...
pain and temperature.
63
Meissner corpuscles are..
large, myelinated fibers that adapt quickly.
64
Meissner corpuscles are located in...
glabrous (hairless) skin.
65
Meissner corpuscles sense...
dynamic, fine/light touch; position sense
66
Pacinian corpuscles are...
large, myelinated fibers that adapt quickly
67
Pacinian corpuscles are in the...
deep skin layers, ligaments and joints.
68
Pacinian corpuscles sens..
vibration and pressure.
69
Merkel discs are...
large, myelinated fibers that adapt slowly.
70
Merkel discs are located in..
the basal epidermal layer and hair follicles.
71
Merkel discs sense...
pressure, deep static touch; position sense
72
The endoneurim surrounds...
a single nerve fiber layers. This is the inflammatory infiltrate in Guillain barre.
73
The perineurium surrounds...
a fascicle of nerve fibers; must be rejoined in microsurgery for limb reattachment; permeability barrier.
74
The epineurium is a...
dense CT that surrounds the entire nerve (fascicles and blood vessels).
75
NE is synthesized in...
the locus ceruleus (pons).
76
Dopamine is synthesized in...
the ventral tegmentum and SNc (midbrain).
77
5-HT is synthesized in...
the raphe nucleus (pons, medulla, midbrain)
78
ACh is synthesized in...
the basal nucleus of Myenert.
79
GABA is synthesized in...
the nucleus accumbens.
80
NE change in disease (2)
increased in anxiety decreased in depression
81
Dopamin change in disease (3)
increased in Huntington decreased in Parkinson decreased in depression
82
Serotonin change in disease (3)
increased in Parkinson decreased in anxiety decreased in depression
83
ACh change in disease (3)
increased in Parkinson decreased in Alzheimer decreased in Huntington
84
GABA change in disease (2)
decreased in anxiety decreased in Huntington
85
The BBB is formed by 3 structures:
1. tight junctions between nonfenestrated capillary endothelial cells 2. basement membrane 3. astrocyte foot processes
86
Glucose and amino acids cross the BBB via...
slow, carrier-mediated transport.
87
Nonpolar/lipid-soluble substances cross the BBB via...
rapid diffusion.
88
Areas of the brain w/o BBB allow for special brain functioning (3):
1. area postrema (vomiting after chemo) 2. OVLT (osmotic sensing) 3. neurohypophysis (ADH release)
89
In regards to the BBB, infarction or neoplasm can destroy...
endothelial cell tight junctions leading to vasogenic edema.
90
Functions of the Hypothalamus (7)
TAN HATS 1. Thirst and water balance 2. Adenohypophysis control 3. Neurohypophysis regulates hormones produced in the hypothalamus 4. Hunger 5. Autonomic regulation 6. Temperature regulation 7. Sexual urges
91
ADH is made in the...
supraoptic nucleus.
92
Oxytocin is made in the...
paraventricular nucleus.
93
ADH and oxytocin are both made by...
the hypothalamus but stored and released by the posterior pituitary.
94
Lateral area of the Hypothalamus
Hunger (destruction leads to anorexia and FTT) inhibited by leptin
95
Ventromedial area of the hypothalamus
Satiety (destruction leads to hyperphagia) stimulated by letin
96
Anterior hypothalmus
cooling, parasympathetic
97
Posterior hypothalamus
heating, sympathetic
98
Suprachiasmatic nucleus
circadian rhythm
99
Circadian rhythm controls the nocturnal release of...
ACTH, prolactin, melatonin, and NE.
100
The SCN releases...
NE to the pineal gland which releases melatonin.
101
SCN is regulated by...
the environment (light).
102
Extraocular movements during REM sleep are due to...
activity of PPRF (paramedian pontine reticular formation).
103
Alcohol, benzodiazapenines, and barbituates are associated with...
decreased REM sleep and delta wave sleep.
104
Bedwetting should be treated with...
oral desmopressin (DDAVP) which mimics ADH.
105
Treat night terrors and sleepwalking with...
benzodiazepines.
106
Awake (eyes open) EEG
beta waves (high frequency, low amplitude)
107
Awake (eyes closed) EEG
alpha
108
Stage 1 NREM is...
light sleep with theta waves.
109
Stage 2 NREM is...
deeper sleep with sleep spindles and K complexes that makes up 45% of sleep.
110
Bruxism occurs during...
Stage 2 sleep.
111
Stage 3 NREM is...
deepest slow-wave sleep with delta waves (low frequency, high amplitude).
112
Sleepwalking, night terrors and bedwetting occur during...
stage 3 sleep.
113
REM sleep features
-loss of motor tone -increased brain O2 use -increased pulse/bp -memory processing function? -Beta waves
114
Dreaming and clitoral/penile tumescence occurs during...
REM.
115
The posterior pituitary (neurohypophysis) receives...
hypothalamic axonal projections from supraoptic (ADH) and paraventricular (oxytocin) nuclei.
116
The thalamus is the major relay for...
all ascending sensory info except olfaction.
117
VPL input
spinothalamic and dorsal columns/medial lemniscus
118
VPL info
pain/temp, pressure, touch, vibration and proprioception
119
VPL destination
primary somatosensory cortex
120
VPM input
trigeminal and gustatory pathway
121
VPM info
face sensation and taste
122
VPM destination
primary somatosensory cortex
123
LGN input
CN II
124
LGN info
vision
125
LGN destination
calcarine sulcus
126
MGN input
superior olive and inferior colliculus of tectum
127
MGN info
hearing
128
MGN destination
auditory cortex of the temporal lobe
129
VL input
basal ganglia and cerebellum
130
VL info
motor
131
VL destination
motor cortex
132
Cerebellum input
1. contralateral cortex via middle cerebellar peduncle 2. ipsilateral proprioceptive info via inferior cerebellar peduncle from the spinal cord
133
Cerebellum outputs information to the contralateral cortex to...
modulate movement. It starts at the purkinje cells then to the deep nuclei then to the contralateral cortex via the superior cerebellar peduncle.
134
Deep nuclei (from lateral to medial)
Dentate, Emboliform, Globose, Fastigial
135
Lateral lesions of the cerebellum affect...
voluntary movement of the extremities; when injured, there is a propensity to fall toward the injured side
136
Medial lesions of the cerebellum involve...
vermal cortex, fastigial nuclei and flocculonodular lobe resulting intruncal ataxia, nystagmus and head tilting.
137
Pts with medial lesions of the cerebellum may present with...
a wide-based gait and deficits in truncal coordination.
138
The basal ganglia is important in...
voluntary movements and making postural adjustments.
139
Basal ganglia receives...
cortical input and provides negative feedback to the cortex to modulate movement.
140
The exicatory pathway receives cortical inputs that...
stimulate the striatum to release GABA which disinhibits the thalamus via the GPi/SNr (leading to increased motion).
141
The inhibitory pathway receives cortion inputs that..
stimulate the striatum which disinhibits STN via GPe and then STN stimulates GPi/SNr to inhibit the thalamus (decreased motion).
142
In the excitatory pathway, dopamine binds to...
D1 stimulating the excitatory pathway. (increases motion)
143
In the inhibitory pathway, dopamine binds to...
D2 inhibiting the inhibitory pathway (increased motion).
144
Parkinson is a degenerative disorder of the CNS associated with...
Lewy bodies and loss of dopaminergic neurons in the substantia nigra pars compacta.
145
Lewy bodies are composed of..
alpha-synuclein - intracellular eosinophilic inclusions.
146
Clinical findings of Parkinson (5)
1. tremor (pill-rolling) 2. cogwheel rigidity 3. Akinesia 4. postural instability 5. shuffling gait
147
Huntington Disease features
-autosomal dominant -trinucleotide repeat of CAG on chr 4 -20-50 yrs old
148
Huntington is characterized by...
choreiform movements, aggression, depression and dementia.
149
Huntington pathology is due to...
decreased levels of ACh and GABA in the caudate. (atrophy of caudate on imaging)
150
In Huntington, neuronal death is via...
NMDA-R binding and glutamate toxicity.
151
Hemiballismus presentation
sudden, wild flailing of 1 arm +/- ipsilateral leg
152
Characteristic lesion of hemiballismus
contralateral subthalamic nucleus (ex. lacunar stroke)
153
Chorea presentation
sudden, jerky, purposeless movements
154
Characteristic lesion of chorea and athetosis
basal ganglia
155
Athetosis presentation
slow, writhing movements (esp in fingers)
156
Myoclonus (sudden, brief, uncotrolled muscle contraction) is common in...
metaboic abnormalities such as renal and liver failure.
157
Dystonia is...
sustained, involuntary muscle contractions. Ex. writer's cramp, blepharospasm
158
Essential tremor (postural tremor) is an..
action tremor; exacerbated by holding posture/limb position
159
Treatment for essential tremor
beta-blockers primidone
160
Resting tremor is an...
uncontrolled movement of distal appendages; tremor is alleviated by intentional movement
161
Intetion tremor is a...
slow, zigzag motion when pointing/extending toward a target.
162
Characteristic lesion of intention tremor...
cerebellar dysfunction.
163
Lesion to the bilateral amygdala causes...
Kluver-Bucy syndrome (hyperorality, hypersexuality, disinhibited behavior); associated with HSV-1.
164
Lesions to the frontal lobe cause...
disinhibition and deficits in concentration, orientation and judgement; may have reemergence of primitive reflexes.
165
Lesions to the right parietal-temporal cortex cause...
spatial neglect syndrome (agnosia of the contralateral side of the world)
166
Lesions to the left parietal-temporal cortex cause...
agraphia, acalculia, finger agnosia and left-right diorientation (aka Gerstmann syndrome)
167
Lesion to the reticular activating system (midbrain) causes...
reduced levels of arousal and wakefulness
168
Lesion to the mamillary bodies causes...
Wernicke-Korsakoff syndrome (confusion, ophthalmoplegia, ataxia, memory loss, confabulation and personality changes.
169
Mamillary body lesions are associated with...
thiamine deficiency and excessive EtOH use; can be precipitated by giving glucose w/o B1 to a B1 deficient pt.
170
Basal ganglia lesion may result in...
tremor at rest, chorea or athetosis.
171
Cerebellar hemisphere lesions lead to..
intention tremor, ataxia and loss of balance
172
Cerebellar vermis lesions lead to...
truncal ataxia and dysarthria.
173
Lesions in the subthalamic nucleus lead to...
contralateral hemiballismus.
174
Lesions to the hippocampus cause..
anterograde amnesia.
175
Lesions to the paramedian pontine reticular formation lead to...
eyes looking away from the side of the lesion.
176
Lesions to the frontal eye fields lead to...
eyes looking toward the lesion.
177
Central pontine myelinolysis causes...
acute paralysis, dysarthria, dysphagia, diploplia and loss of consiousness. Can cause "locked-in syndrome".
178
Central pontine myelinolysis pathology is due to...
massive axonal demyelination in pontine white matter tracts secondary to osmotic forces and edema.
179
Central pontine myelinolysis is commonly iatrogenic caused by...
overly rapid correction of hyponatremia.
180
Broca's aphasia
nonfluent aphasia with intact comprehension
181
Broca's area is located in the...
inferior frontal gyrus of the frontal lobe.
182
Wernicke's aphasia is...
fluent aphasia with impaired comprehension and repetition.
183
Wernicke's area is located in the...
superior temporal gyrus of the temporal lobe.
184
Global aphasia is...
nonfluent aphasia with impaired comprehension; both broca and wernicke areas are affected.
185
Conduction aphasia
poor repetition but fluent speech; intact comprehension
186
Conduction aphasia can be caused by damage to..
left superior temporal lobe and/or left supramarginal gyrus.
187
Transcortical motor aphasia
nonfluent aphasia with good comprehension and repetition
188
Transcortical sensory aphasia
poor comprehension with fluent speech and repetition
189
Mixed transcortical aphasia
nonfluent speech, poor comprehension, and good repetition
190
Watershed zones of the brain are damaged in severe...
hypotension leading to upper leg/arm weakness and defects in higher-order visual processing.
191
Cerebral perfusion is primarily driven by...
PCO2 (PO2 can help in severe hypoxia).
192
Therapeutic hyperventilation (decreases PCO2) helps to decrease...
intracranial pressure in cases of acute cerebral edema via decreased cerebral perfusion by vasoconstriction.
193
If there is a lesion in the MCA supply to the motor cortex, this causes...
contralateral paralysis of the upper limb and face.
194
If there is a lesion in the MCA supply to the sensory cortex, this causes....
contralateral sensation of the upper and lower limbs and face.
195
If there is a lesion in the MCA supply to Wernicke's or Broca's area regions, this causes...
aphasia if in the dominant hemisphere (usually left) and hemineglect if it affects the nondominant side.
196
If there is a lesion in the ACA supply to the motor cortex, this causes...
contralateral paralysis in the lower limb.
197
If there is a lesion in the ACA supply to the sensory cortex, this causes...
contralateral loss of sensation in the lower limb.
198
If there is a lesion in the lenticulostriate artery to the striatum and internal capsule, this causes...
contralateral hemiparesis/hemiplegia.
199
A lesion in the ASA to the lateral corticospinal tract will cause...
contralateral hemiparesis (arms and legs).
200
A lesion of the ASA to the medial lemniscus will cause...
decreased contralateral proprioception.
201
A lesion of the ASA to the caudal medulla will cause...
ipsilateral hypoglossal dysfunction (causing the tongue to deviate ipsilaterally).
202
Medial Medullary syndrome is caused by...
infarct of paramedian branches of ASA and vertebral arteries.
203
A lesion to the PICA will affect the...
lateral medulla (vestibular nuclei, lateral spinothalamic tract, spinal trigeminal nucleus, nucleus ambiguus, sympathetic fibers, and inferior cerebellar peduncle).
204
Symptoms of a PICA lesion include...
vomiting, vertigo, nystagmus decreased pain and temp sensation from ipsilateral face and contralateral body dysphagia hoarseness decreased gag reflex ipsilateral Horner ataxia dysmetria (Lateral Medullary Syndrome - Wallenberg)
205
AICA lesion affects the...
lateral pons (cranial nerve nuclei, vestibular nuclei, facial nucleus, spinal trigeminal nucleus, cochlear nuclei, sympathetic fibers). (Lateral Pontine Syndrome)
206
AICA lesion affecting the lateral pons causes...
vomiting, vertigo, nystagmus paralysis of the face decreased lacrimation and salivation decreased taste from 2/3 anterior tongue decreased corneal reflex decreased pain/temp in face ipsilateral decreased hearing and Horner
207
AICA lesions can also affect the middle and inferior cerebellar peduncles leading to...
ataxia and dysmetria.
208
PCA lesion affects the...
occipital cortex and visual cortex causing contralateral hemianopia with macular sparing.
209
Lesion to the basilar artery affects...
the pons, medulla, lower midbrain, corticospinal and corticobulbar tracts, ocular crainal nerve nuclei, and PPRF.
210
Basilar artery lesion causes...
"locked in syndrome": quadriplegia, loss of voluntary facial, mouth and tongue movements. (preserved consciousness and blinking)
211
Most common lesion of the anterior communicating artery is...
an aneurysm which can lead to visual field defects and stroke.
212
Saccular aneurysms can cause...
cranial nerve impingment.
213
The posterior communicating artery is a common location of...
saccular aneurysms where they cause CNIII palsy (pupil is down/out with ptosis and dilation).
214
Aneurysms are...
abnormal dilation of the artery due to weakening of the vessel wall.
215
Berry aneurysms occur at...
the birfucations of the circle of willis, most commonly the junction of the ACA and anterior communicting a.
216
Rupture of berry aneurysms leads to...
subarachnoid hemorrhage (worst HA of life) or hemorrhagic stroke. Can also cause
217
Berry aneurysms can also cause bitemporal hemianopia due to..
compression of the optic chiasm.
218
Berry aneurysms are associated with...
ADPKD Ehlers-Danos Marfan
219
Risk factors of Berry aneurysms include...
advanced age HTN smoking race (AA)
220
Charcot-Bouchard microaneurysms are associated with..
chronic HTN and they affect small vessels (in basal ganglia, thalamus).
221
Central post-stroke pain syndrome is...
neuropathic pain due to thalamic lesions. Initial sense of numbness and tingling followed by allodynia and dysaesthesia.
222
Epidural hematoma is ususally due to..
rupture of the middle meningeal artery secondary to fracture of the temporal bone.
223
Rapid expansion is seen in epidural hematoma leading to...
transtentorial herniation and CN III palsy.
224
CT of an epidural hematoma shows...
convex (lentiform), hyperdense blood collection.
225
Epidural hematoma does not cross...
suture lines. It can cross falx and tentorium.
226
Subdural hematomas are usually due to...
rupture of bridging veins casuing slow venous bleeding.
227
Subdural hematomas are seen in...
elderly individuals, alcoholics, blunt trauma, shaken baby.
228
CT of a subdural hematoma shows...
crescent-shaped hemorrhage that crosses suture lines. Cannot cross falx, tentorium.
229
Time course of a subarachnoid hemorrhage is...
rapid and pts complain of worst HA of life. Due to rupture of aneurysm.
230
Spinal tap of subarachnoid hemorrhage shows...
bloody or yellow (xanthochromic) spinal tap.
231
2-3 days after a subarachnoid hemorrhage, there is risk of..
vasospasm due to blood breakdown (not visible on CT, treat with nimodipine) and rebleed (visible on CT).
232
Intraparenchymal (hypertensive) hemorrhage is most commonly caused by...
systemic HTN. Also seen with amyloid angiopathy, vasculitis and neoplasm.
233
Intraprenchymal hemorrhages typically occur in...
basal ganglia and internal capusle but can be lobar.
234
Irreversible damage from stroke begins after...
5 minutes of hypoxia.
235
Most vulnerable brain regions to stroke (ischemia) are:
-hippocampus -neocortex -cerebellum -watershed areas
236
Histology 12-48 hrs after ischemic event
red neurons
237
Histology 24-72 hrs after ischemic event
necrosis + neurtrophils
238
Histology 3-5 days after ischemic event
macrophages
239
Histology 1-2 wks after ischemic event
reactive gliosis + vascular proliferation
240
Histology more than 2 weeks after ischemic event
glial scar
241
Hemorrhagic strokes are...
intracerebral bleeds often due to HTN, anticoagulation and cancer. May be secondary to ischemic stroke followed by reperfusion.
242
Most common site of hemorrhagic stroke
basal ganglia
243
Ischemic stroke is...
acute blockage of vessels leading to disruption of blood flow and subsequent ischemia resulting in liquefactive necrosis.
244
3 types of ischemic stroke:
1. thrombotic 2. embolic 3. hypoxic
245
Thrombotic stroke is typically due to...
a clot forming directly at the site of infarction (commonly MCA), usually over an atherosclerotic plaque.
246
Embolic stroke is due to...
an embolus from another part of the body that obstructs a vessel; can affect multiple vascular territories.
247
Hypoxic stroke is due to..
hypoperfusion or hypoxemia. Common during CV surgeries; tends to affect watershed areas.
248
Treatment for ischemic stroke
tPA if within 3-4 hours of onset and no risk of hemorrhage.
249
Ischemic stroke risk can be decreased with...
aspirin or clopidogrel, bp control, and control of sugars and lipids.
250
A transient ischemic attack (TIA) is...
a brief, reversible episode of focal neurologic dysfunction lasting \<24 hrs w/o acute infarction causing deficits due to focal infarction.
251
The dural venous sinsues drain blood from...
cerebral veins and empty into the internal jugular vein. They receive CSF from arachnoid granulations.
252
The lateral ventricle empties to the...
3rd ventricle via the interventricular foramina of Monro.
253
The 3rd ventricle empties to the...
4th ventricle via the cerebral aqueduct.
254
The 4th ventricle empties to the...
subarachnoid space via the foramina of Luschka (Laterally) and the foramen of Magendie (medially).
255
CSF is made by...
ependymal cells of choroid plexus. It is reabsorbed by arachnoid granulations and then drains into dural venous sinuses.
256
A communicating hydrocephalus is due to...
decreased CSF absorption by the arachnoid granulations which can lead to increased intracranial pressure, papilledema and herniation. (ex. from arahnoid scarring post-meningitis)
257
Normal pressure hydrocephalus does not result in...
increased subarachnoid volume.
258
Normal pressure hydrocephalus is due to expansion of the...
ventricles that distorts the fibers of the corona radiata and leads to clinical triad of urinary incontinence, ataxia and cognitive dysfunction.
259
Hydrocephalus ex vacuo has the appearance of...
increased CSF that is actually the result of decreased neural tissue due to atrophy. Intracranial pressure is normal. Seen in Alzheimer, advanced HIV and Pick disease.
260
A noncommunicating hydrocephalus is caused by...
a structural blockage of CSF circulation within the ventricular system (ex. stenosis of the cerebral aqueduct).
261
There are 31 spinal nerves:
8 cervical 12 thoracic 5 lumbar 5 saccral 1 coccygeal
262
Nerves C1-C7 exit...
above their corresponding vertebra and all other nerves exit below. Ex. C3 exits above the 3rd cervical vertebra and L2 exits below the 2nd lumbar vertebra.
263
Vertebral disc herniation
nucleus pulposus herniates through the annulus fibrosus; usually occurs posterolaterally at L4-L5 or L5-S1
264
The spinal cord extends to...
the lower border of L1-L2 vertebrae.
265
The subarachonid space (contains CSF) extends to...
lower border of S2 vertebra so lumbar puncture is usually performed between L3-L4 or L4-L5 (level of cauda equina).
266
In the spinal cord, the legs are...
lumbosacral and lateral in the lateral corticospinal tract and spinothalamic tract.
267
The dorsal column is for...
ascending pressure, vibration, fine touch and proprioception.
268
1st order neuron of the dorsal column
sensory nerve ending leads to the cell body in the DRG which enters the spinal cord and ascends ipsilaterally in the dorsal column
269
1st synapse of the dorsal column
ipsilateral nucleus cuneatus or gracilis in the medulla
270
2nd order neuron of the dorsal column
decussates in the medulla and ascends contralaterally in the medial lemniscus
271
Synapse 2 of the dorsal column
VPL of the thalamus
272
3rd order neuron of the dorsal column
sensory cortex
273
Spinothalamic tract function
-ascending -lateral: pain/temp -anterior: crude touch/pressure
274
1st order neuron of the spinothalamic tract
sensory nerve ending has cell body in DRG and enters spinal cord
275
Synapse 1 of spinothalamic tract
ipsilateral gray matter in spinal cord
276
2nd order neuron of the spinothalamic tract
decussates at the anterior white commissure and then ascends contralaterally
277
Synapse 2 of the spinothalamic tract
VPL (thalamus)
278
3rd order neuron of the spinothalamic tract
sensory cortex
279
Lateral corticospinal tract fxn
descending: voluntary movement of contralateral limbs
280
1st order neuron of the corticospinal tract
UMN: cell body in primary motor cortex that descends ipsilaterally (through internal capsule), and most fibers decussate at the caudal medulla (pyramidal decussation) and then descend contralaterally
281
Synapse 1 of the lateral corticospinal tract
cell body of the anterior horn
282
2nd order neuron of the lateral corticospinal tract
LMN: leaves spinal cord
283
synapse 2 of the lateral corticospinal tract
NMJ
284
Weakness sign
+ UMN lesion + LMN lesion
285
Atrophy sign
- UMN lesion +LMN lesion
286
Fasciculations sign
- UMN lesion + LMN lesion
287
Reflexes sign
increased UMN lesion decreased LMN lesion
288
Tone sign
increased UMN lesion decreased LMN lesion
289
Babinski sign
+ UMN lesion - LMN lesion
290
Spastic paralysis sign
+ UMN lesion - LMN lesion
291
Flaccid paralysis sign
- UMN lesion + LMN lesion
292
Clasp knife spasticity
+ UMN lesion - LMN lesion
293
Werdnig-Hoffman Disease (poliomyelitis and spinal muscular atrophy) characteristics
-LMN lesions only -due to destruction of anterior horns -flaccid paralysis
294
Multiple Sclerosis characteristics
-due to demyelination -mostly affects white matter of the cervical region -random and asymmetric lesions -scanning speech -intention tremor -nystagmus
295
Amyotrophic lateral sclerosis characteristics
-combined UMN adn LMN deficity w/ no sensory, cognitive or oculomotor deficits
296
ALS can be caused by a defect in...
superoxide dismutase 1.
297
ALS commonly presents as...
fasciculations with eventual atrophy and weakness of hands; fatal.
298
Treatment for ALS
riluzole can modestly increase survival by decreasing presynaptic gluatamate release.
299
Complete occlusion of the anterior spinal artery characteristics
-spares dorsal columns and Lissauer tract -upper thoraic ASA territory is a wather shed area bc artery of Adamkiewicz supplies ASA below T8
300
Tabes dorsalis is caused by...
tertiatry syphilis and results from degeneration of the dorsal columns and roots leading to impaired sensation adn proprioception and progressive senosry ataxia (cant feel legs = poor coordination).
301
Tabes dorsalis is associated with...
Charcot joints, shooting pain, Argyll Robertson pupils.
302
Argyll Robertson pupils are...
small, bilateral pupils taht further constrict to accomodation and convergence but not to light.
303
Exam of Tabes dorsalis will demonstrate...
absence of DTRs and + Romberg.
304
Syringomyelia causes damage to...
the anterior white commissure of the spinothalamic tract (2nd order neurons) leading to bilateral loss of pain and temp.
305
Vit B12 or E deficiency leads to...
subacute combined degeneration (demyelination of the dorsal columns, lateral corticospinal tracts and spinocerebellar tracts) leading to ataxic gait, paresthesia, impaired position and vibration sense.
306
Poliomyelitis is caused by...
poliovirus which replicates in the oropharynx and small intestine before spreading via the bloodstream to the CNS.
307
Poliovirus infection causes destruction of...
cells in the anterior horn of the spinal cord (LMN death).
308
Symptoms of poliomyelitis
LMN lesion signs (weakness, hypotonia, flaccid paralysis, fasciculations, hyporeflexia, and muscle atrophy) -infection signs (fever, malaise, nausea, etc.)
309
Findings of poliomyelitis
-CSF w/ increased WBCs and slight increase in protein - virus recovered from stool or throat
310
Spinal muscular atrophy (Werdnig Hoffmann disease)
congenital degeneration of anterior horns of the spinal cord leading to a LMN lesion; autosomal recessive inheritance
311
Spinal muscular atrophy presents as...
a "floppy baby" with marked hypotonia and tongue fasciculations
312
Friedreich ataxia is due to...
an autosomal recessive trinucleotide repeat (GAA) on chr 9 that encodes frataxin (iron binding protein).
313
Friedreich ataxia causes...
degeneration of multiple spinal cord tracts leading to muscle weakness, loss of DTRs, vibratory sense and proprioception
314
Friedreich ataxia presents in childhood with...
kyphoscoliosis. -staggering gait -frequent falling -nystagmus -dysarthria -ps cavus -hammer toes -hypertrophic cardiomyopathy (cause of death)
315
Brown-Sequard syndrome is due to...
hemisection of the spinal cord.
316
Findings of Brown-Sequard
-ipsilateral UMN signs -ipsilateral loss of tactile, vibration and proprioception -contralateral pain and temp loss -ipsilateral loss of all sensation at the level of the lesion -ipsilateral LMN signs at the level of the lesion
317
If a brown-sequard lesion occurs above T1, a pat may present with...
Horner syndrome due to damage of the oculosympathetic pathway.
318
Horner syndrome
Sympathectomy of the face: -Ptosis -Anhidrosis (and flushing) -Miosis (pupil constriction)
319
Horner syndrome is associated with...
lesion of the spinal cord above T1. (Pancoast tumor, Brown-Sequard syndrome, late-stage syringomyelia)
320
The 3-neuron oculosympathetic pathway projects from...
the hypothalamus to the intermediolateral column of the spinal cord then to the superior cervical (sympathetic) ganglion and finally to the pupil, smooth muscle of the eyelid and sweat glands.
321
C2 dermatome
posterior half of skull cap
322
C3 dermatome
high turtlenck shirt
323
C4 dermatome
low-collar shirt
324
T4 dermatome
at the nipple
325
T7 dermatome
at the xiphoid process
326
T10 dermatome
at the umbilicus
327
L1 dermatome
at the inguinal ligament
328
L4 dermatome
includes the kneecaps
329
S2, S3, S4 dermatomes
erection and sensation of penile and anal zones
330
Diaphragm and gallbladder pai is referred to the...
right shoulder via the phrenic nerve.
331
Biceps reflex
C5 nerve root
332
Triceps reflex
C7 nerve root
333
Patella reflex
L4 nerve root
334
Achilles reflex
S1 nerve root
335
Cremaster reflex
L1, L2
336
Primitive reflexes are inhibited by...
a mature/developing frontal lobe and may reemerge in adults with frontal lobe lesions.
337
Moro reflex
"hang on for life" reflex - abduct/extend limbs when startled and then draw them together
338
Rooting reflex
movement of head toward one side if cheek or mouth is stroked
339
Sucking reflex
sucking response when roof of mouth is touched
340
Palmar reflex
curling of fingers if palm is stroked
341
Plantar reflex
dorsiflexion of large toe and fanning of others with plantar stimulation (Babinski sign)
342
Galant reflex
stroking along one side of the spine while the newborn is in ventral suspension causes lateral flexion of the lower body toward the stimulated side
343
CNs that lie medially at the brain stem
III VI XII (motor = medial)
344
Pineal gland
-melatonin secretion -circadian rhythm
345
Superior colliculi
conjugate vertical gaze center
346
Inferior colliculi
auditory
347
Parinaud syndrome
paralysis of conjugate vertical gaze due to a lesion in the superior colliculi (pinealoma)
348
CN I
Olfactory - smell \*\*only CN w/o thalamic relay
349
CNII
Optic - sight
350
CNIII
Oculomotor - eye movement (SR, IR, MR, IO), pupillary constriction, accomodation, eyelid opening
351
CN IV
Trochlear - eye movemetn (SO)
352
CN V
Trigeminal - mastication, facial sensation (ophthalmic, maxillary, mandibular divisions), somatosensation from the anterior 2/3 of the tongue
353
CN VI
Abducens - eye movement (LR)
354
CN VII
Facial - facial movement, taste from anterior 2/3 of tongue, lacrimation, salivation, eyelid closure, stapedius muscle in ear
355
The facial nerve courses through...
the parotid gland but does not innervate it.
356
CN VIII
vestibulocochlear - hearing and balance
357
CN IX
Glossopharyngel - taste and somatosensation from posterior 1/3 of tongue, swallowing, salivation, monitoring carotid body and sinus chemo/baro receptors and stylopharyngeus.
358
The stylopharyngeus acts to...
elevate the pharynx and larynx. Innervated by CN IX.
359
CN X
Vagus - taste from epiglottic region, swallowing, soft palate elevation, midline uvula, talking, coughing, thoracoabdominal viscera, monitoring aortic arch chemo/baro receptors
360
CN XI
Accessory - head turning, shoulder shrugging (SCM, Trapezius)
361
CN XII
Hypoglossal - tongue movement
362
Cranial nerve nuclei are located in..
the tegmentum portion of the brainstem.
363
Midbrain contains cranial nerve nuclei for:
CN III and IV
364
Pons contains cranial nerve nuclei for:
CN V, VI, VII, and VIII
365
Medulla contains cranial nerve nuclei for:
CN IX, X, and XII
366
Spinal cord contains cranial nerve nucleus for:
CN XI
367
Corneal reflex afferent
V1 ophthalmic
368
Corneal reflex efferent
VII
369
Lacrimation reflex afferent
V1
370
Lacrimation reflex efferent
VII
371
Jaw jerk afferent
V3 (senosry - muscle spindle from masseter)
372
Jaw jerk efferent
V3 (motor - masseter)
373
Pupillary reflex afferent
II
374
Pupillary reflex efferent
III
375
Gag reflex afferent
IX
376
Gag reflex efferent
X
377
Vagal nuclei (3)
1. nucleus solitarius 2. nucleus ambiguus 3. dorsal motor nucleus
378
Nucleus solitarius
visceral sensory information (taste, baroreceptors, gut distention) VII, IX, X
379
Nucleus ambiguus
motor innervation of pharynx, larynx and upper esophagus (swallowing, palate elevation) IX, X, XI
380
dorsal motor nucleus
sends autonomic (PNS) fibers to the heart, lungs and upper GI X
381
CN 1 pathway entrance
cribiform plate
382
CN II - VI pathway entrance
middle cranial fossa through the sphenoid bone
383
Optic canal carries...
CN II ophthalmic artery central retinal vein
384
Superior orbital fissure carries...
CN III, IV, V1, and VI ophthalmic vein sympathetic fibers
385
Foramen Rotundum carries..
CN V2
386
Foramen Ovale carries...
CN V3
387
Foramen spinosum carries...
middle meningeal artery
388
CN VII- XII pathway entrance
posterior cranial fossa through teh temporal or occipital bone
389
Internal auditory meatus carries...
CN VII and VIII
390
Jugular foramen carries...
CN IX, X, XI and jugular vein
391
Hypoglossal canal carries...
CNXII
392
Foramen magnum carries...
spinal roots of CN XI brain stem vertebral arteries
393
The cavernous sinus is a collection of...
venous sinuses on either side of the pituitary.
394
The cavernous sinus collects blood from the....
eye and superficial cortex and sends it to the internal jugular vein.
395
Structures that pass through the cavernous sinus include...
CN III, IV, V1, V2 and VI and postganglionic sympthetic fibers. Also the internal carotid artery.
396
Cavernous sinus syndrome is...
ophthalmoplegia and decreased corneal and maxillary sensation with normal visual acuity. CN VI is commonly affected.
397
Cavernous sinus syndrome is due to...
mass effect, fistula, thrombosis, etc.
398
CN V motor lesion causes...
the jaw to deviate toward the side of the lesion due to unopposed force from the opposite pterygoid muscle.
399
CN X lesion causes...
the uvula to deviate away from the side of the lesion. The weak side collapses and the uvula points away.
400
CN XI lesion casues...
weakness turning the head to the contralateral side of the lesion (SCM). Should droop on the side of the lesion (trapezius).
401
CN XII lesion
tongue deviates toward side of the lesions due to weakened muscles on the affected side
402
Outer ear is the...
visible portion of the ear (pinna) that includes the auditory canal and eardrum. Transfers sound waves via vibration of the ear drum.
403
Middle ear is...
an air-filled space with three bones called the ossicles (malleus, incus, stapes).
404
The ossicles act to...
conduct and amplify sound from the eardrum to the inner ear.
405
The inner ear is...
the fluid-filled cochlea. It contains the basilar membrane the vibrates secondary to sound waves.
406
In the inner ear, vibration is transduced via...
specialized hair cells sending an auditory nerve singal to the brainstem.
407
Each frequency leads to vibration at a specific location on the basilar membrane (tonotopy):
-low frequency is heard at the apex near the helicotrema (wide and flexible) -high frequency is heard best at the base of the cochlea (thin and rigid)
408
Conductive Hearing Loss test findings
Rinne - abnormal (bone \> air) Weber - localizes to affected ear
409
Sensorineural Hearing loss test findings
Rinne - normal (air \> bone) Weber - localizes to unaffected ear
410
Noise-induced hearing loss is due to...
stereocilliated cells in the organ of Corti; loss of high-frequency hearing first.
411
Sudden, extremely loud noises can produce hearing loss due to...
tympanic membrane rupture.
412
UMN facial lesion
contralateral paralysis of lower face; forehead spared due to bilateral UMN innervation
413
LMN facial lesion
ipsilateral paralysis of upper and lower face
414
Facial nerve palsy is due to...
complete destruction of the facial nucleus itself or its branchial efferent fibers.
415
Symptoms of facial nerve palsy
peripheral ipsilateral facial paralysis (drooping smile) with inability to close eye on involved side
416
Facial nerve palsy is associated with...
Lyme disease, HSV, herpes zoster, sarcoidosis, tumors and diabetes.
417
Treatment of facial nerve palsy
corticosteroids
418
3 muscles that close the jaw
1. Masseter 2. teMporalis 3. Medial pterygoid M's Munch
419
1 muscle that closes the jaw
lateral pterygoid
420
The masseter, temporalis, medial pterygoid and lateral pterygoid are all innervated by...
the trigeminal nerve (V3).
421
Refractive errors are...
impaired vision that improves with glasses: 1. hyperopia 2. myopia 3. astigmatism 4. presbyopia
422
Hyperopia is when the eye is...
too short for the refractive power of the cornea and lens causing light to be focused behind the retina.
423
Myopia is when the eye is...
too long for the refractive power of the cornea and lens and light is then focused in front of the retina.
424
Astigmatism is an...
abnormal curvature of the cornea resulting in different refractive power at different axes.
425
Presbyopia is...
a decrease in focusing ability during accomodation due to sclerosis and decreased elasticity.
426
Uveitis is...
inflammation of the anterior uvea and iris with hypopyon (sterile pus) accompanied by conjunctival redness.
427
Uveitis is often associated with...
systemic inflammatory disorders (sarcoid, RA, TB, etc.)
428
Retinitis is...
retinal edema and necrosis leading to a scar.
429
Retinitis is often...
viral (CMV, HSV, HZV) and associated with immunosuppression.
430
Central retinal artery occlusion is...
blockage of central or branch retinal vein due to compression from nearby arterial atherosclerosis. This causes retinal hemorrhage and edema in the affected area.
431
Non-proliferative diabetic retinopathy
damaged capillaries lead blood leading to lipids and fluid seeping into the retina leading to hemorrhages and macular edema
432
Treatment for Diabetic retinopathy
blood sugar control and macular laser
433
Proliferative diabetic retinopathy
chronic hypoxia results in new blood vessel formation with resultant traction on the retina
434
Treatment for proliferative diabetic retinopathy
peripheral retinal photocoagulation and anti-VEGF injections
435
Glaucoma is...
optic disc atrophy with characteristic cupping, usually with increased intraocular pressure and progressive peripheral visual field loss
436
Open angle glaucoma is associated with...
increased age, AA race, family history. It is painless and more common in US.
437
Secondary open angle glaucoma is due to...
blocked trabecular meshwork from WBCs, RBCs and retinal elements
438
Primary closed angle glaucoma is due to...
enlargement of the lens against the centril iris leadings to obstruction of normal aqueous flow through the pupil leading to fluid building up behind the iris, pushing the peripheral iris against the cornea and impeding flow through the trabecular meshwork
439
Secondary closed angle glaucoma is due to..
hypoxia from retinal disease that induces vasoproliferation in the iris that contracts the angle
440
Chronic closure (glaucoma) is often...
asymptomatic with damage to the optic nerve and peripheral vision.
441
Acute closure (glaucoma) is a true...
ophthalmic emergency. Increased intraocular pressure pushes the iris forward leading to abrupt angle closure.
442
Acute closure glaucoma presents with...
extreme pain, sudden vision loss, halos around lights, rock-hard eye, and frontal HA.
443
Epinephrine should not be given for acute closure glaucoma due to...
it mydriatic effect.
444
A cataract is...
a painless, often bilateral, opacification of the lens leading to a decrease in vision.
445
Risk factors for Cataract
-increased age -smoking -alcohol -excessive sunlight -prolonged corticosteroid use -classic galactosemia -galactokinase deficiency -diabetes -trauma -infxn
446
Papilledema is...
optic disc swelling due to increased intracranial pressure
447
Findings of Papilledema
enlarged blind spot and elevated optic disc with blurred margins seen on fundoscopic exam
448
CN III damage
eye looks down and out; ptosis, pupillary dilation and loss of accomodation
449
CN IV damage
eye moves upward (especially w/ contralateral gaze and head tilt)
450
People with CN IV damage may have problems with...
going down the stairs and will present with a compensatory head tilt in the opposite direction.
451
CN VI damage
medially directed eye that cannot abduct
452
Miosis is...
pupil constriction controlled parasympathetically.
453
Miosis nerve pathway
1st neuron: Edinger-Westphal nucleus to ciliary ganglion via CN III 2nd neuron: short ciliary nerves to pupillary sphincter muscles
454
Mydriasis is...
pupil dilation controlled sympathetically.
455
Mydriasis nerve pathway
1st neuron: hypothalamus to ciliospinal center of Budge 2nd neuron: exit at T1 to superior cervical ganglion 3rd neuron: plexus along the internal carotid, through the cavernous sinus; enters orbit as long ciliary nerve to pupillary dilator muscles
456
The pupillary light reflex is when light in...
the retina sends a signal via CN II to pretectal nuclei in the midbrain that activates bilateral Edinger-Westphal nuclei.
457
Result of the pupillary light reflex
illumination of 1 eye results in bilateral pupillary constriction
458
Marcus Gunn pupil is an...
afferent pupillary defect due to optic nerve damage or severe retinal injury leading to decreased bilateral pupillary constriction to light is in the affected eye.
459
Marcus Gunn pupil can be tested with the...
"swinging flashlight test".
460
Motor output of CN III to the ocular muscles is affected primarily by..
vascular disease due to decreased diffusion of oxygen adn nutrients to the interior fibers from compromised vasculature that resides on the outside of a nerve
461
Signs of damage to the motor portion of CN III
ptosis; down and out gaze
462
Damage to the parasympathetic output of CN III is due to..
compression (ex. posterior communicting artery aneurysm or uncal herniation).
463
Signs of damage to the parasympathetic output of CN III
diminished or absent pupillary light reflex, "blown pupil" often with down and out gaze
464
Retinal detachment is...
separation of neurosensory layer of retina (photoreceptor layer w/ rods and cones) from the outermost pigmented epithelium leading to degerenration of photoreceptors and vision loss.
465
Retinal detachment may be secondary to...
retinal breaks, diabetic traction and inflammatory effusions.
466
Retinal breaks are more common in pts with...
high myopia and are often preceded by posterior vitreous detachment (flashes and floaters) and monocular loss of vision like a "curtain drawn down".
467
Age-related macular degeneration causes...
distortion (metamorphopsia) and eventual loss of central vision (scotomas).
468
Dry macular degeneration
deposition of yellowish extracellular material in and beneath the Bruch membrane and retinal pigment epithelium (drusen) with a gradual decrease in vision
469
Dry macular degeneration progress can be prevented with...
multivitamin and antioxidants.
470
Wet macular degeneration is...
rapid loss of vision due to bleeding secondary to choroidal neovascularization.
471
Wet macular degeneration can be treated with...
anti-VEGF or laser.
472
When an image hits the visual cortex, it is...
upside down and left-right reversed.
473
The Meyer loop carries signals from the...
inferior retina and loops around the inferior horn of the lateral ventricle.
474
The Dorsal optic raiation carries signals from the..
superior retina and takes the shortes path via the internal capsule.
475
The medial longitudinal fasciculus (MLF) is a...
pair of tracts that allows for crosstalk between CN VI and CN III nuclei.
476
The MLF coordinates...
both eyes to move in the same horizontal direction.
477
The MLF is highly...
myelinated so lesions are seen in pts with demyelination (MS).
478
A lesion in the MLF causes..
Internuclear ophthalmoplegia (INO).
479
Lesions in the MLF (aka INO) causes a lack of communication such that when the CN VI nucleus activates the ipsilateral lateral rectus, the...
contralateral CN III nucleus does not stimulate the meddial rectus. Thus, the abducting eye gets nystagmus (bc CN VI overfires to stimulate CN III).
480
Dementia is a...
decrease in the cognitive ability, memory or function w/ intact consciousness.
481
The most common cause of dementia in the eldely is...
Alzheimer disease.
482
The familial form (10%) of Alzheimer is associated with the following proteins:
-Early onset: APP, presenilin-1, presenilin-2 -Late onset: ApoE4
483
ApoE2 is...
protective for Alzheimer.
484
Gross findings of Alzheimer
-cortical atrphy -narrowing of gyri -widening of sulci
485
Histologic findings of Alzheimer
-senile plaques -neurofibrillary tanlges (also decreased ACh)
486
Senile plaques have an...
extracellular beta-amyloid core. They may cause amyloid angiopathy leading to intracranial hemorrhage.
487
Abeta (amyloid-beta) is synthesized by..
cleaving amyloid precursor protein (APP).
488
Neurofibrillary tangles are...
intracellular, hyperphosphorylated tau protein = insoluble cytoskeletal elements. The number of tangles correlates with the degree of dementia.
489
Pick disease (frontotemporal dementia) presents with...
dementia, aphasia, parkinsonian aspects, and change in perosnality. Frontotemporal atrophy.
490
Pick disease spares the...
parietal lobe and posterior 2/3 of the temporal gyrus.
491
Pick bodies are...
spherical tau protein aggregates.
492
Lewy body dementia presents with...
initial dementia and visual hallucinations followed by parkinsonian features.
493
Lewy body dementia is due to a defect in...
alpha-synuclein.
494
Cretuzfeldt-Jakob disease is...
rapidly progressive dementia with myoclonus.
495
Findings of Creutzfeldt-Jakob
-spongiform cortex -prions (PrPsc sheet = beta-pleated sheet resistant to proteases)
496
Other causes of dementia (7)
-multi infarct -syphilis -HIV -vitamins -B1, B3, B12 deficiency -Wilson disease -NPH
497
Multiple sclerosis is...
autoimmune inflammation and demyelination of the CNS.
498
MS pts present with...
-optic neuritis (sudden loss of vision resulting in Marcus Gunn pupils) -internuclear ophthalmoplegia (INO) -hemiparesis -hemisensory symptoms -bladder/bowel incontinence
499
MS most often affects...
whites, women in 20s or 30s.
500
MS findings (4)
-increased protein (IgG) in the CSF -oligoclonal bands (diagnostic) -periventricular plaques -multiple white matter lesions separated in time and space
501
Periventricular plaques are...
areas of oligodendrocyte loss and reactive gliosis.
502
Gold standard for diagnosis MS is...
MRI.
503
Treatment for MS
-beta-interferon -immunosuppression -Natalizumab
504
Symptomatic treatment for MS
-bladder: cath, muscarinic antagonists -spasticity: baclofen, GABA receptor agonist -pain: opioids
505
Acute inflammatory demyelinating polyradiculopathy is an..
autoimmune condition that destroys schwann cells leading to inflammation and demyelination of peripheral nerves and motor fibers.
506
Acute inflammatory demyelinating polyradiculopathy results in...
symmetric ascending muscle weakness/paralysis beginning in the lower extremities. Facial paralysis in 50%. Autonomic function affected (cardiac irregularities, bp change).
507
Acute inflammatory demyelinating polyradiculopathy is the most common variant of...
Guillain barre.
508
Findings of acute inflammatory demyelinating polyradiculopathy
-increased CSF protein w/ normal cell count -papilledema
509
Acute inflammatory demyelinating polyradiculopathy is associated with...
infections (Campylobacter jejuni and CMV) leading to an autoimmune attack of peripheral myelin due to molecular mimicry. Also, inoculations and stress.
510
Treatment for acute inflammatory demyelinating polyradiculopathy
-respiratory support -plasmapheresis -IVIG
511
Progressive multifocal leukoencephalopathy (PML) is...
demyelination of the CNS due to destruction of oligodendrocytes.
512
PML is associated with...
JC virus and seen in 3% of AIDS pts.
513
PML is rapidly...
progressive and usually fatal. Increased risk with Natalizumab.
514
Acute disseminated encephalomyelitis is...
multifocal perivenular inflammation and demyelination after infxn (measles/VZV) or certain vaccinations (rabies/smallpox).
515
Metachromatic leukodystrophy is an...
autosomal recessive lysosomal storage disease due to arylsulfatase A deficiency.
516
In metachromatic leukodystrophy, deficiency of arylsulfatase A leads to a...
buildup of sulfatides causing impaired production of myelin.
517
Findings of metachromatic leukodystrophy
central and peripheral demyelination with ataxia, dementia
518
Charcot-Marie-Tooth disease is a group of...
progressive, hereditary nerve disorders related to the defective production of proteins involved in the structure and fxn of peripheral nerve or the myelin sheath.
519
Charcot-Marie-Tooth disease is associated with...
scoliosis and foot deformities. AD inheritance.
520
Krabbe disease is a...
autosomal recessive lysosomal storage disease due to deficiency of galactocerebrosidase leading to buildup of galactocerebroside and psychosine which destroys the myelin sheath.
521
Findings of Krabbe disease
-peripheral neuropathy -developmental delay -optic atrophy -globoid cells
522
Adrenoleukodystrophy is an...
X-linked disorder affecting males that disrupts the metabolism of very-long-chain fatty acids leading to excessive buildup in the nervous system, adrenal gland and testes.
523
Partial seizures affect...
1 area of the brain. Most commonly originate in the medial temporal lobe.
524
Partial seizure are often preceded by...
seizure aura.
525
Types of partial seizure
1. simple partial 2. complex partial
526
Simple partial seizures
consciousness intact; affect motor, sensory, autonomic and psychic factors
527
Complex partial seizures have..
impaired consciousness.
528
Generalized seizures are...
diffuse. Types: 1. Absence 2. Myoclonic 3. Tonic-Clonic 4. Tonic 5. Atonic
529
Absence seizure features
-3 hz -no postictal confusion -blank stare
530
Myoclonic seizure features
-quick, repetitive jerks
531
Tonic-clonic featuers
-alternating stiffening and movement
532
Tonic seizures
stiffening
533
Atonic seizures
"drop" seizures (falls to floor)
534
Epilepsy is a disorder of...
recurent seizures.
535
Status epilepticus
continuous seziure for \> 30 min or recurrent seizures w/o gaining consciousness for \> 30 min
536
Causes of seizure in children
genetic infection trauma congenital metabolic
537
Causes of seizure in adults
tumors trauma stoke infection
538
Causes of seizure in the elderly
stroke tumor trauma metabolic infection
539
Localization and duration of cluster headaches
unilateral 15 min-3 hr; repetitive
540
Description of cluster HAs
repetitive brief HAs; excruciating periobrital pain w/ lacrimation adn rhinorrhea; may induce Horner; more common in males
541
Treatment of Cluster HAs
inhaled oxygen sumatriptan
542
Localization and duration of tension headaches
bilateral \>30 min (usually 4-6 hrs)
543
Description of tension HAs
-steady pain -no photophobia or phonophobia -no aura
544
Treatment of tension HAs
-analgesics, NSAIDs, acetaminophen -amitriptyline (for chronic pain)
545
Migraine localization and duration
-unilateral -4-72 hrs
546
Description of Migraine
-pulsating pain w/ nausea, photophobia or phonophobia -may have "aura"
547
Migraine is due to...
irritation of CN V, meninges, or blood vessels (release of substance P, CGRP, vasoactive peptides).
548
Migraine treatment
-abortive (triptans, NSAIDs) -prophylactic (propranolol, topiramate, calcium channel blcokers, amitriptyline)
549
Cluster HAs can be differentiated from trigeminal neuralgia based on...
duration. trigeminal neuralgia produces repetitive shooting pain that lasts for less than one minute.
550
Vertigo is...
a sensation of spinning while actually stationary.
551
Peripheral vertigo etiology is...
inner ear (semicircular canal debris, vestibular nerve infxn, meniere)
552
Positional testing of peripherla vertigo shows...
delayed horizontal nystagmus
553
Central vertigo etiology is...
brainstem or cerebellar lesion (stroke, etc).
554
Findings of central vertigo
directional change of nystagmus skew deviation diploplia dysmetria
555
Positional testing of central vertigo shows...
immediate nystagmus in aany direction; (focal neurologial findings are also present)
556
Sturge-Weber Syndrome
congential, non-inherited, developmental anomaly of neural crest derivatives (mesoderm/ectoderm) due to an activating mutation of GNAQ gene
557
Sturge-Weber affects...
small blood vessels causing port-wine stain on face, ipsilateral leptomeningeal angioma (causing seizures/epilepsy); intellectual disability; and episcleral hemangioma (leading to increased IOP and early onset glaucoma).
558
Tuberous sclerosis
HAMARTOMAS -Hamartomas -Angiofibromas -Mitral regurgitation -Ash-leaf spots -cardiac Rhabdomyoma -Tuberous sclerosis -autosomal dOminant -Mental retardation -renal Angiomyolipoma -Seizures, Shagreen patches
559
Tuberous sclerosis pts have an increased incidence of...
subependymal astrocytomas and ungual fibromas.
560
Neurofibromatosis type I findings
-cafe-au-lait spots -Lisch nodules (pigmented iris hamartomas) -neurofibromas in skin, optic gliomas, pheochromocytomas
561
Neurofibromatosis type I is due to...
a mutated NF1 tumor suppressor gene (neurofibromin, negative regulator of Ras).
562
Skin tumors of NF1 are derived from..
neural crest cells.
563
von Hippel-Lindau disease findings
-cavernous hemangiomas in the skin, mucosa, organs -bilateral RCC -hemangioblastoma in retina, brain stem and cerebellum -pheochromocytoma
564
von Hippel-Lindau inheritance and pathology
-autosomal dominant -mutated VHL tumor suppressor which results inconstitutive activity of HIF and activation of angiogenic growth factors
565
Glioblastoma multiforme is a common...
highly malignant primary brain tumor with about one year survival. It is a grade IV astrocytoma.
566
Glioblastoma multiforme is found in the...
cerebral hemisphers anc can cross the corpus callosum ("butterfly glioma").
567
Glioblastoma multiforme stains with...
GFAP (for astrocytes).
568
Histology of glioblastoma multiforme
pseudopalisading pleomorphic tumor cells that border a central area of necrosis and hemorrhage
569
Meningioma is a common...
benign, primary brain tumor.
570
Meningioma most commonly occurs in the...
convexities of the hemispheres.
571
Menigiomas arise from...
arachnoid cells, is extra-axial and may have a dural attachment.
572
Meningioma is often asymptomatic but may present with..
seizures or focal neurological signs. Can treat with resection or radiosurgery.
573
Histology of meningioma
spindle cell concentricall arranged in a whorled pattern; psammoma bodies
574
Hemangioblastoma is most often...
cerebellar. It can produce erythropoietin leading to secondary polycythemia.
575
Hemangioblastoma is associated with...
von Hippel-Lindau syndrome when found with retinal angiomas
576
Hemangioblastoma histology
closely-arranged, thin-walled capillaries with minimal interleaving parenchyma
577
Schwannoma is ususally found at...
the cerebellopontine angle and has schwann cell origin.
578
Schwannoma is positive for..
S-100.
579
Schwannoma is often localized to...
CN VIII causing acoustic schwannoma.
580
Oligodendroglioma is relatively...
rare and slow growing. It is most often in the frontal lobes.
581
Oligodendroglioma featuers
-chicken-wire capillary pattern -often calcified
582
Oligodendroglioma histology
-fried egg cells (round nuclei w/ clear cytoplasm)
583
Pituitary adenoma is most commonly a...
prolactinoma.
584
Pituitary adenomas cause...
bitemproal hemianopia (due to pressure on optic chiasm). and hyper/hypo pituitarism.
585
Childhood primary brain tumors (4)
1. pilocytic astrocytoma 2. medulloblastoma 3. ependymoma 4. craniopharyngioma
586
Pilocytic astrocytoma features
-well-circumscribed -found in posterior fossa -GFAP + -benign
587
Pilocytic astrocytoma histology
-rosenthal fibers (eosinophilic, corkscrew fibers)
588
Medulloblastoma is a highly...
malignant cerebellar tumor (form of primitive neuroectomderm)
589
Medulloblastoma can...
compress the 4th ventricle causing hydrocephalus and can send "drop metastases" to the spinal cord.
590
Medulloblastoma histology
Homer-Wright rosettes small blue cells
591
Ependymoma is most commonly found in..
the 4th ventricle and can cause hydrocephalus. Poor prognosis.
592
Histology of ependymoma
-perivascular rosettes -rod-shaped blepharoplasts found near nucleus
593
Craniopharyngioma is a...
benign tumor. Most common childhood supratentorial tumor. Calcification is common. Can cause bitemporal hemianopia.
594
Craniopharyngioma is derived from...
remnants of Rathke pouch.
595
Cingulate herniation is under the...
falx cerebri and can compress the anterior cerebral artery.
596
Uncal herniation compresses...
the ipsilateral CN III, ipsilateral PCA, and the contralateral crus cerebri (ipsilateral paralysis; false localization sign).
597
Cerebellar tonsiallar herniation is into the...
foramen magnum. Coma and death result when these herniations compress the brain stem (and inhibit respiration).
