Neurology Flashcards
1
Q
Neural tube development
A
1) Notochord induces ectoderm to differentiate into neuroectoderm and form neural plate
2) Neural plate gives rise to neural tube and neural crest cells
3) Notochord becomes nucleus pulposus of intervertbral disc
Alar plate- dorsal, sensory
Basal plate- ventral, motor
2
Q
Regionalization of the brain
A
PRimary vesicles: prosencephalon (forebrain), mesencephalon (midbrain), rhombencephalon (hindbrain)
Secondary vescles
-prosencephalon – telencephalon (cerebral hemispheres and lateral venticles) and diencephalon (thalamus and third ventricle)
-mesencephalon – midbrain and cerebral aqueduct
rhombencephalon –metencephalon (pons and cerebellum) and myelencephalon (medulla); both contribute to fourth ventricle
3
Q
Neuroectoderm derivatives
A
CNS neurons, epednymal cells that line the ventricles and make CSF, oligodendroglia, astrocytes
4
Q
Neural crest derivatives
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PNS neurons and schwann cells
5
Q
mesoderm derivatives
A
microglia (hematopoietic lineage)
6
Q
Testing for neural tube defects
A
Elevated AFP in maternal serum and amniotic fliud
Elevated AChE in amniotic fluid
7
Q
Spina bifida occulta
A
Failure of bony spinal canal to close without any structural herniation and with dura intact. AFP is normal. Least severe neural tube defect.
8
Q
Meningocele and Meningomyelocele
A
Meningocele: meninges only herniate through bony defect
Meningomyelocele: meninges and nural tissue hernate through bony defect; associated with chiari II malformation
both have risk of ascending infection
Look like plaquode on skin
9
Q
Holoprosencephaly
A
Not a neural tube defect. Failure of left and right hemispheres to separate. Can be caused by sonic hedgehog mutations. Associated with Patau syndrome and FAS. Associated with cleft palate/lip, cyclopia
10
Q
Chiari II
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Hernation of cerebellar tonsils and vermis through foramen magnum. Aqueductal sternosis and hydrocephalus as result. Meningomyelocele (neural tube defect) is associatd
11
Q
Dandy Walker malformation
A
Agenesis of cerebellar vermis with cystic enlargement of the fourth ventricle. Associated with hydrocephalus and spina bifida
12
Q
Syringomyelia
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Cystic cavity in spinal cord. Typicall damages corssing anterior spinal commisurral fibers leading to cape like loss of pain and temp in upper extremities. Associated with chiari I
13
Q
Chiari I malformation
A
Cerebellar tonsils herniate. Associated with syringomyelia. Usually asymptomatic in childhood
14
Q
Tongue development
A
1st and second branchial arches: anterior 2/3 with sensation from V3, taste from VII
3rd and 4th arches form posterior 1/3 with sensation and taste from IX and X
Motor from X (palatoglossus) and XII (all others)
15
Q
Nissl stain
A
Stains RER and can be used to visualize cell bodies and dendrites of neurons. Doesn’t stain axon as RER is not present: proteins are synthesized in the cell body and transported down the axon
16
Q
Wallerian degeneration
A
In response to axonal injury, the nerve degenerates distal to the injury and the axon retracts proximally, allowing for regeneration if in the PNS. Regeneration occurs slowly over weeks to months.
17
Q
Astrocytes
A
Functions: physical support, repair, potassium metabolism, removal of excess neurotransmitter (take up glutamate and convert to glutamine), component of BBB, reactive gliosis in response to neuronal injury, match cerebral blood flow to synaptic activity
Marker: GFAP
Derivative of neuroectoderm
18
Q
HIV in the brain
A
Infect microglia, which fuse to form multinucleated giant cells in the CNS
19
Q
Scwann cells
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Each Schwann cell myelinates 1 PNS axon. Promote axonal regeneration. Derived from neural crest
20
Q
Oligodendroglia
A
Myelinate axons of CNS. Each oligodendrocyte can myelinate many axons. Derived from neuroectoderm. Fried egg appearance
21
Q
Types of sensory receptors: free nerve endings, meissner corpuscles, pacinian corpuscles, merkel discs, ruffini corpuscles
A
Free nerve endings: Carry pain on C fibers, temp on Adelta fibers. Located in skin and seome viscera
Meissner corpuscles: Carry fine touch and position on large myelinated fibers that adapt quickly. Found on hairless skin
Pacinian corpuscles: Carry vibration and pressure on large myelinated fibiers that adapt quickly. Found in deep skin layers, ligaments, and joints.
Merkel discs: Carry pressure, deep touch, and position on large myelinated fibers that adapt slowly. Found in fingertips and superficial skin
Ruffini corpuscles: Carry pressure information on slow adapting dendritic endings within the capsule
22
Q
Layers of a peripheral nerve
A
Endoneurium: surrounds single nerve fibers
Perineurium: surround fasicle of nerve fibers
Epineurium: dense connective tissue surrounding entire nerve
23
Q
Location of neurotransmitter synthesis: NE, DA, 5-HT, ACh, GABA
A
NE: locus ceruleus of the pons Dopamine: ventral tegmentum and substantia niagra of midbrain 5-HT: Raphe nuclei in brainstem ACh: Basal nucleus of Meynert GABA: nucleus accumbens
24
Q
Components of BBB
A
- Tight junctions between nonfenestrated capillary endothelial cells
- Basement membrane
- Astrocyte foot processes
25
OVLT
Area of hypothalamus not protected by BBB that senses changes in osmolarity.
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Area postrema
Area of hypothalamus not protected by BBB that responds to emetics
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Supraoptic nucleus
Part of hypothalamus that makes ADH
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PAraventricular nucleus
Part of hypothalamus that makes oxytocin
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Hypothalamus: lateral, ventromedial, anterior, posterior, suprachiasmic nucleus
Lateral area: hunger, inhibited by leptin
Ventromedial area: Satiety, stimulated by leptin
Anterior hypothalamus: Cooling, parasympathetic
Posterior hypothalamus: Heating, sympathetic
Suprachiasmic nucleus: Circadian rhythm
30
Circadan rhythm
Controlled by suprachiasmic nucleus. Drives nocturnal release of ACTH, prolactin, melatonin, norepinephrin.
31
Effect of CNS depressants on sleep
EtOH, benzos, and barbs decrease REM sleep and delta wave sleep
32
Pathology of different sleep stages
Non-REM stage N2: bruxism (teeth grinding)
| Non-REM stage N3: sleepwalking, night terrors, bed wetting
33
Thalamic nuclei
VPL: Spinothalamic tract and dorsal column relay to sensory cortex
VPM: Trigeminal and taste relat to sensory cortex
LGNL Received vision info from CNII and sends to calcarine sulcus
MGN: Reveives auditory info from sup olive and inf collicular and sends to auditory cortex
VL: Reveives motor info from basal ganglia and cerebellum and relays to motor cortex
34
Limbic system
Includes hippocampus, amygdala, fornix, mamillary bodies, and cingulate gyrus
35
Central pontine myelinolysis
Result of overly rapidly correcting hyponatremia. Results in acute paralysis, LOC, locked in syndrome
36
Pathways through basal ganglia
Excitatory: Cortical inputs stimulate striatum; striatum stimulates release of GABA which disinhibits the thalamus via GPi/SNr
Inhibitors: Cortical inputs stimulate striatum, disinhibits STN via GPe, STN stimulates GPI/SNr to inhibit thalamus.
37
Dopamine receptors
D1: stimulates excitatory pathway
D2: inhibits inhibitory pathway
both increase motion
38
Hemiballismus
Decreased activity of subthalamic nucleus decreasing GPint activity, increasing thalamic activity and causing flailing. Sudden wild flailing of 1 arm and sometimes ipsilateral leg due to damage to contralateral subthalamic nucleus
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Athetosis
Slow writhing movements of the fingers seen with lesions to basal ganglia, such as in Huntington
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Treatment of essential tremor
beta blcokers
| primidone
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Myoclonus
Sudden, brief, uncontrolled muscle contraction seen iwth metabolic abnormalities
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Pathology of PD
Lewy bodies of alpha synuclein which have intracellular eosinophilic inclusions. Loss of dopaminergic neurons of substantia niagra
43
Neurotransmitters in HD
DA increased
GABA decreased
ACh decreased
44
Broca aphasia
Nonfluent aphasia with intact comprehension, impaired repetition.
Broca area in inferior frontal gyrus of frontal lobe
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Wernicke aphasia
Fluent aphasia with impaired comprehension and repetition.
Wernicke area is in superior temporal gyrus of termporal lobe
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Conduction aphasia
Poor repetition but fluent speech and intact comprehension
Can be caused by damage to arcuate fasciculus
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Global aphasia
Nonfluent aphasia with impaired comprehension
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Transcortical motor aphasia
Nonfluent, good comprehension, intact repetition
49
Transcortical sensory aphasia
Poor comprehension, fluent speech, intact repetition
50
Mixed transcortical aphasia
Nonfluent speech, poor comprehension, intanct repetition
51
Kluver Bucy syndrome
Bilateral damage to amygdalae. Disinhibited behavior with hyperphagia, hypersexuality, hyperorality. Associated with HSV-1
52
Frontal lobe lesions
Cause disinhibition, problems with concentration, orietnation, judgement, possible reemergence of primitive reflexes
53
Parietal-temporal cortex lesions
Nondominant: hemispatial neglect syndrome
Dominant: Gerstmann syndrome of agraphia, acalculia, finger agnosia, left-right disorientation
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Reticular activating system lesions
Reduced levels of arousal and wakefulness
55
Wernicke-Korsakoff syndrome
Pathology: affects mammillary bodies
Presentation: confusion, ophthalmoplegia, ataxia, memory loss, personality changes, confabulation
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Basal ganglia lesions
Resting tremor, chorea, athetosis
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Cerebellar lesions
Hemisphere: Intention tremor, limb ataxia, loss of balance. Ipsilateral defects; fall toward side of lesion
Vermis: Truncal ataxia, dysarthria
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Hippocampal lesions
Anterograde amnesia
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Defects to paramedian pontine reticular formation vs frontal eye fields
Paramedian pontine reticular formation: eyes look away from side of lesion
Frontal eye fields: eye look toward lesion
60
Regulation of cerebral perfusion
Driven by Pco2. Po2 modulates only in severe hypoxemia. Increased Pco2 increases cerebral perfusion pressure. Decreased O2
61
Therapeutic hyperventilation
Decreases Pco2 which helps to decrease intracranial pressure in acute cerebral edema via vasoconstrtion (brain thinks it has plenty of oxygen if CO2 is low). Hypventilation in panic attacks decreases perfusion leading to fainting.
62
Cerebral perfusion pressure
CPP = MAP - ICP
So, hypotension or incresaed intracranial pressure can decrease cerebral perfusion
63
Presentation of MCA stroke
Can get contralateral paralysis of upper limb and face due to effect on motor cortex
Can get contralateral sensory loss of uppper limb and face due to effect on sensory cortex
Can get aphasia or hemineglect due to effect on ermporal lobe and frontal lobe
64
Presentation of lenticulostriate artery stroke
Affects striatum and internal capsule. Contralateral hemiparesis/hemiplegia. Often lacunar infarct secondary to unmanaged hypertension
65
Presentation of anterior spinal artery stroke
Affects lateral corticospinal tract: contralateral hemiparesis of upper and lower limbs
Affects medial lemniscus: loss of contralateral proprioception
Affects caudal medulla: ipsilateral hypoglossal dysfunction with tongue deviating ipsilaterally
66
Presentation of PICA stroke
Affects lateral medulla: vomiting, vertigo, nystagmus due to cerebellar dysfunction and effect on vestibular nuclei. Decreased pain and temp sensation from ipsilateral face, contralateral body due to effect on lateral spinothalamic tract. Dysphagia and hoarseness due to effect on nucleus ambiguus. Ipsilateral horner syndrome due to effect on sympathetic fibers
67
Presentation of AICA stroke
Affects lateral pons including middle and inferior cerebellar peduncles. Presents with vomiting, vertigo, nystagmus, face paralysis, ataxia, dysmetria
68
Presentation of PCA stroke
Affects occipital cortex and visual cortex. Contralateral hemianopia with macular sparing
69
Presentation of basilar artery stroke
Locked in syndrome. Preserved consciousness and blinking with quadriplegia and loss of mouth, face, tongue movements
70
Presentation of anterior communicating artery stroke
Most often due to aneurysm. Presents with visual field defect
71
Presentation of posterior communicating artery stroke
Saccular aneurysms. CNIII palsy.
72
Saccular aneurysms
Also called berry aneurysms. Occur at bifurcations of circle of willis, most commonly junction of ACA and ant comm a. Rupture leads to SAH or hemorrhagic stroke. May compress optic chiasm.
73
Diseases associated with saccular aneurysms
ADPKD, Ehlers-danlos
74
Charcot-Bouchard microaneurysm
Associated with chronic HTN. Affects small vessels of basal ganglia and thalamus
75
Central post-stroke pain syndrome
Neuropathic pain due to thalamic lesions. Parasthesias followed by allodynia and dysesthesia
76
Epidural hematoma
Caused by middle meningeal artery rupture secondary to fracture. Classic lucid interval followed by expansion and transtentorial herniation with CNIII palsy. Biconvex blood collection that doesn't cross suture lines, can cross falx, tentorium
77
Subdural hematoma
Caused by rupture of bridging veins. Slow venous bleeed over time. Seen in eldery, alcoholics, blunt trauma, shaken baby. Crescent shaped hemorrhage that crosses suture lines. Cannot cross tentorium
78
SAH
Caused by rupture of an aneurysm or AVM. Rapid ime course. Worst headache of life. Bloody or yellow spinal tap. Risk of vasospasms 2-3 days afterward due to blood breadown and rebleed
79
Intraparenchymal hemorrhage
Associate dwith systemic HTN or amyloid angiopathy, vascultitis, neoplasm. Basal ganglia and internal capsule are most common locations
80
Ischemic brain diesease
irreversible damage 5 mins of hypoxia. Hippocampus, neocorex, and cerebellum most vulnerable.
Imaging: noncontrats CT to exclude hemorrhage. Will detect ischemic changes in 6-24 hours. Diffusion-weighted MRI can detect ischemia much sooner
81
Histologic changes seen after ischemic stroke
```
12-48 hrs: red neurons
24-72 hrs: necrosis and neutrophils
3-5 days: macrophages/microglia
1-2 weeks: reactive gliosis and vascular proliferation
over 2 wks: glial scar
```
82
CSF flow
Made by ependymal cells of choroid plexus. Flows from lateral ventricles through R and L interventricular foramina of monroe into 3rd ventricle, through cerebral aqueduct to 4th ventricle, into subarachnoid space through foramina of luschka (lateral) and foramen of magendie (medial). Reabsorbed by arachnoid granulations. Drains into dural venous singuses
83
Idiopathic intracranial HTN
Also called pseudotumor cerebri. Increased ICP without apparent cause on imaging. Presents with headaches and diplopia without mental status change. Papilledema present. Increased opening pressure on LP.
Risk factors: woman of childbearing age, vitamin A excess, danazol
Treatment: weight los, acetazolamide, topiramate
84
Normal pressure hydrocephalus
Idiopathic condition seen in elderly. CSF pressure elevated episodically. Expansion of ventricles, distorting fibers of corona radiata. Wet, wobbly, and wacky: urinary incontinence, ataxia, cognitive dysfunction
85
Ex vacuo ventriculomegaly
Appearance of increased CSF on imaging due to decreased brain tissue. Normal ICP
86
Spinal nerve naming
C1-C7 exit above corresponding vertebra. C8 exits below C7. Rest exit below their corresponding vertebra
87
Vertebral disc herniation
Nucleus pulposus herniates through annulus fibrosus.
88
Lower extension of spinal cord
Adults: lower border of L1-L2 vertebra. Subarachnoid space to loer border of S2. LP performed between L3/L4 or L4/L5
89
Medial lemniscus
Carries sensory fibers from the nucleus gracilis and cuneatus to LGN
90
Poliomyelitis
Destruction of anterior horns. LMN lesions only (flaccid paralysis). Replicates in oropharynx and sm intestine; then spreads to CNS by blood stream
CSF: increased WBCs and slight increased protein
91
Spinal muscular atrophy
congenital degeneration of anterior hormones. LMN lesions only (flaccid paralysis). Floppy baby with tongue fasciculations. AR inheritance
92
Multiple sclerosis effect on spinal cord
Demyelination mostly of white matter in cervical region. Random and asymmetric lesions
93
Riluzole
Glutamate antagonist used to treat ALS
94
Tabes dorsalis
Caused by tertiary syphilis. Degeneration of dorsal columns and nerve roots resulting in impaired sensation and proprioception and poor coordination. Absent DTRs, pos romberg
95
Vitamin B12 def - effect on spinal cord
Subacute combined degeneration: demyelination of dorsal columns, lateral corticospinal tracts, spinocerebellar tracts resulting in ataxic gait, paresthesia, impaired pos and vibration sense
96
Friedreich ataxia
AR GAA repeat on chromosome 9. Gene encodes iron binding protein frataxin. Leads to impairment of mitochondrial function.
Degeneration of spinal tracts resultingin weakness, loss of DTRs, vibratory sense, and proprioception.
Associated with diabetes and hypertrophic cardiomyopathy. Also kyphoscoliosis
97
Brown Sequard syndrome
Hemisection of cord. If above T1 can cause Horner syndrome as well as spinal cord findings
98
Key dermatomes: C2, C3, C4, T4, T7, T10, L1, L4, S2, S3, S4
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C2: posterior half of skull cap
C3: high turtleneck shirt
C4: low collar shirt
T4: nipple
T7: xiphoid process
T10: umbilicus
L1: inguinal ligament
L4: kneecap
S2, S3, S4: erection and sensation of penis and anus
```
99
Pineal gland
Located above the superior colliculi. Responsible for melatonin secretion and circadian rhythms
100
Supeiror and inferior colliculi
Superior: conjugate vertical gaze
Inferior: auditory function
101
Locations of cranial nerve nuclei
Midbrain: III and IV
Pons: V, VI, VII, VIII
Medulla: IX, X, XII
Spinal cord: XI
Latearl nuclei are sensory, originating from alar plate
Medial nuclei are motor, originating from basal plate
102
Optic canal: what travels through
CNII, ophthalmic artery, central venous vein
103
Superior orbital fissure: what passes through
CNIII, IV, V1, VI (all nerve to eye except optic) + opthalmic vein and sympathetic fibers
104
Foramen rotundum
Carries CN V2
105
Foramen ovale
Carries CN V3
106
Foramen spinosum
Holds middle meningeal artery
107
Internal auditory meatus
Carries CN VII and VIII
108
Jugular foramen
Carries CN IX, X, XI, jugular vein
109
Hypoglossal canal
Carries CN XII
110
Foramen magnum
Carries spinal roots of CN XI, brainstem, vertebral arteries
111
Function of CN IV and XI
IV (trochlear) innervates superior oblique
| VI (abducens) innervates lateral rectus
112
Sensation of tongue
Somatosensory for anterior 2/3: CNV
Taste for anterior 2/3: CNVII
Taste and somatosensory for posterior 1/3: CNIX
Taste from epiglottic region: CNX
113
Carotid and aoritc body monitoring
CNIX monitors carotid body and sinus chemo and baroreceptors
| CNX monitors aortic arch chemo and baroreceptors
114
Nucleus solitarius
Visceral sensory information for CNVII, IX, X - taste, baroreceptors, gut distention
115
Nucleus ambiguus
Motor information for pharynx, larynx, upper esophagus. CNIX, X, XI
116
Dorsal motor nucleus
Autonomic fibers of CNX to heart, lungs, upper GI tract
117
Gag reflex
Afferent: IX
Efferent: X
118
Cavernous sinus
Collection of venous sinuses on either side of pituitary. Blood from eye and superficial cortex drains into cavernous sinus which drains into internal jugular vein.
CN III, IV, V1, VI pass through to get to orbit
119
Cavernous sinus syndrome
Ophthalmoplegia, decreased corneal sensation, Horner syndrome due to pituitary tumor mass effect, fistula, cavernous sinus thrombosis affecting nerves that pass through
120
Tonotopy of basilar membrane
Low freq heard at apex which is wide and flexible
| High freq heard at base of cochlea which is thin and rigid
121
Test results for conductive vs senorineural hearing loss
Conductive hearing loss: Rinne test abnormal with bone greater than air. Weber test localizes to affected ear
Sensorineural hearing loss: Rinne test normal wiht air greater than bone conduction. weber localizes to unaffected ear
122
Noise induced hearing loss
Damages hair cells. Leads to loss of high freq hearing loss first
123
Cholesteatoma
Overgrowth of desquamated keratin debris within middle ear. May errode ossicles and mastoid air cells leading to conductive hearing loss
124
UMN vs LMN lesion of face
UMN: causes contralateral paralysis of the face. upper face is spared because it gets bilateral UMN innervation
LMN: causes ipsilateral paralysis of upper and lower face
125
Muscles of mastication
Masseter, temporalis, and medial pterygoid close the jaw
Lateral pterygoid opens
126
Aqueous humor pathway
Produrced by ciliary epithelium. Collected by trabecular meshwork, then goes into canal of schlemm to drain
127
Refractive errors: hyperopia, myopia, astigmatism, presbyopia
Hyperopia: eye too short; light focused behind retina
Myopia: eye too long; light focused in front of retina
Astigmatism: abnormal curvature of cornea
Presbyopia: age-related impaired acommodation due to decreased lens elasticity
128
Glaucoma
Opitc disc atrophy with cupping. Elevated IOP, progressive peripheral vision loss
129
Open angle glaucoma
Painless and more common. Associated with age, african america, famiy history. Can be secondary to blocked trabecular meshwork with WBCs, RBCs, retinal elements
130
Tetrodotoxin
Toxin found in puffer fish. Binds to NA+ channels, inhibiting influx
131
Morphine effect on ion channels
Binds to mu receptors and causes G protein coupled acivation of K+ channels to increase K+ efflux, hyperpolarizing post-synatpic neurons and terminating pain transmission
132
Kinesin
MT associated motor protein that does anterograde transport of intracellular vesicles and organelles toward plus end of MTs.
133
Valproate during pregnancy
Increases risk of neural tube defects because inhibits folic acid absorption
134
Length constant vs time constant
Length constant: How far long an axon an impulse can propagate. Increased by myelin so that conduction occurs faster.
Time constant: How long it takes for a change in membrane potential to occur. Reduced by myelination so that conduction occurs faster.
135
POMC
Polypeptide precursor that goes through enzymatic modification to produce beta endorphins, ACTH, and MSH
136
Tetrahydrobiopterin
BH4. Cofactor in synthesis of serotonin, DOPA, and tyrosine
137
CSF findings in MS
Increased protein in CSF - oligoclonal bands diagnostic
138
Treatment of MS
Disease modifying therapies: beta-interferon, natalizumab
Acute flares: IV steroids
139
Treatment of Guillan Barre
Respiratory support. Plasmapheresis. IVIG
140
Acute disseminated encephalomyelitis
Multifocal periventricular inflammation and demyelination after infection or certain vaccinations. Commonly seen after measles or VZV
141
Charcot-Marie-Tooth disease
Progressive hereditary nerve disorders due to defective protein production. AD inheritance. Associated with scoliosis and foot deformities
142
Krabbe disease
AR lysosomal storage disease due to def of galactocerebrosidase. Causes galactocerebroside to build up and destroy myelin. Presents with peripheral neuropathy, developmental delay, optic atrophy, globoid cells
143
Metachromatic leukodystrophy
AR lysosomal storage disease. Arylsulfatase A def. Central and peripheral demyelination with ataxia and dementia
144
Progressive multifocal leukoencephalopathy
Demyelination of CNS due to oligodendrocyte destruction. Associated with JC virus - seen in AIDS patients. Radpily progressive and fatal.
145
Adrenoleukodystrophy
X-linked genetic disorder. Disupted metabolism of VLCFA causing build up in NS, adrenal, testes.
146
Positional testing for nystagmus
Delayed horizontal nystagmus suggests peripheral (inner ear) vertigo
Immediate nystagmus in any direction suggests central vertigo
147
Sturge-Weber syndrome
Congenital anomaly of neural crest derivatives due to acivating GNAQ mutation. Affects capillaries leading to port-wine stain on face. Ipsilateral leptomeningeal angioma causes seizures. Intellectual disability. Episcleral hemangioma leads to elevated IOP and early onset glaucoma
148
Tuberous sclerosis
```
Hamartomas in CNS and skin.
Angiofibromas
Mitral regurg
Ash-leaf spots
Cardiac rhabdomyoma
mental retardation
renal angiomylolipoma
seizures
shagreen patches
Autosomal dominant inheritance
```
149
Cancers seen with von hippel lindau
hemangioblastomas of retina, brain stem, cerebellum, and spine
angiomatosis
bilateral renal cell carcinoma
pheochromocytoma
150
Glioblastoma multiforme pathology
Found in cerebral hemispheres and can cross the corpus callosum. Stains positive for GFAP. Pseudopalisading, pleomorphic tumors cells: tumor cells border areas of necrosis and hemorrhage
151
Meningioma presentation and pathology
Presentation: Seizures or focal neurologic signs due to compression of brain tissue
Pathology: spindle cells in whorled paterns; psammoma bodies
152
Hemangioblastoma
Associated with VHL syndrome. Usually cerebellar. Can make EPO leading to polycythemia.
153
Schwannoma: location and tumor marker
Found at cerebellopontine angle. S-100 positive.
154
Oligodendroglioma
Slow growing, usually in frontal lobes. Fried egg cell appearance. Often calcified
155
Pilocytic astrocytoma
Well circumscribed posterior fossa tumor of childhood. GFAP +. Benign with good prognosis. Rosenthal fibers
156
Medulloblastoma histology
Homer-Wright rosettes. Solid small blue cells
157
Ependymoma
Ependymal cell tumor found in 4th ventcile. Can cause hydrocephalus. Poor pronosis. Perivascular rosettes on histology
158
Craniopharyngioma
Benign tumor of childhood in sella turcica. Presents with bitemporal hemianopia. Derived from Rathke pouch remnants. Commonly calcified
159
Cingulate herniation
Cingulate gyrus herniates under falx cerebri. Can compress ACA
160
Transtentorial herniation
Can displace brain stem leading to duret hemorrhages; usually fatal
161
Uncal hernation
Uncus herniates downward and compresses CNIII and PCA
162
Cerebellar tonsilar herniation
Herniates into foramen magnum. Can compress brainstem resulting in coma and death
163
MOA of opioids
Agonize opioid recetpors. Open K+ channels and close Ca++ channels to reduce synaptic transmission. Inhibit release of ACh, NE, 5-HT, glutamate, substance P
164
Butorphanol
MOA: kappa opioid agonist, mu opioid partial agonist
Less resp depression than full opioid agonist
Can cause withdrawal in someone also taking full agonist due to competition at mu receptor
165
Tramadol
MOA: weak opioid agonist; inhibits 5-HT and NE reuptake
Toxicity: decreased seizure threshold, serotonin syndrome
166
Ethosuximide toxicity
Itching, stevens johnson syndrome
167
Phenytoin: MOA, pharmacokinetics, side effects, use
MOA: Increases Na+ channel inactivation
Kinetics: 0 order kinetics
Side effects: gingival hyperplasia, P450 induction, stevens johnson
Use: First line for tonic-clonic seizures and prophylaxis of status epilepticus; can be used for everything except absence
168
Carbamazepine: MOA, side effects, use
MOA: Increases Na+ channel inactivation
Side effects: agranulocytosis and aplastic anemia, teratogenic, P450 induction, SJS
Use: First line for partial seizures and tonic-clonic seizures, first line for trigeminal neuralgia
169
Valproic acid: MOA, side effects, use
MOA: Increases Na+ channel inactivation, increases GABA
Side effects: hepatotoxicity, neural tube defects
Use: First line for tonic clonic seizures, effective against all seizure types. Myoclonic seizures, bipolar
170
Gabapentin: MOA, side effects, use
MOA: inbhits VG Ca++ channels
Side effects: sedation and ataxia
Use: Partial seizures, peripheral neruopaty
171
Phenobarbitol for seizures: MOA, side effects, use
MOA: Increases GABAa action
Side effects: sedation, tolerance and dependence, resp depression, P450 induction
Use: First line in neonatal seizures
172
Topiramate: MOA, side effects, use
MOA: blocks Na+ channels, increases GABA
Side effects: Sedation, mental dulling
Use: Partial and tonic-clonic seizures. Migraine prophylaxis
173
Lamotrigine
MOA: blocks VG Na+ channels
Side effects: SJS
Use: All seizure types, including absence
174
Levetiracetam use
Partial and tonic-clonic seizures
175
Tiagabine MOA and use
Inhibits GABA reuptake. Used for partial seizures
176
Vigabatrin
Increases GABA. Used for partial seizures
