Week 5 Flashcards

(174 cards)

1
Q

Dura mater

A

Most superficial covering; double layer of collagenous tissue; forms venous sinuses; adhered to skull

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2
Q

Epidural space

A

potential space that can fill with blood after skull fracture

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3
Q

arachnoid mater

A

fibroblasts and meningothelial cells; adhered to dura; villi (granulations) penetrate dural venous sinuses to conduct CSF into circulation

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4
Q

subdural space

A

potential space between dura and arachnoid maters; veins pass through, can be torn in minor trauma

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5
Q

pia mater

A

layer of cells tightly adhered to brain surface; anchors strands of arachnoid trabecular

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6
Q

subarachnoid space

A

arachnoid trabecular passes through; with aging, collagen is deposited; also subject to infection, neoplasm infiltration, and hemmorages

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7
Q

Virchow-Robinson space

A

perivenular space between arterial tunica and pia; continuous with subarachnoid space

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8
Q
A

Neuron. Large perikaryon; lots of nissl substance (RER), but abscent at axon hillock; large nucleus with prominant nucleolus and dispersed chromatin

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9
Q

Reactive Astrocytes

A

Response to brain injury. hyperplasia and hypertrophy

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10
Q
A

Astrocyte. Glial cell; major function is to wrap foot processes around the basement membrane of blood vessels and non-synaptic parts of neurons–nutrient exchange; short and highly branched in gray matter, sparse and straighter in white matter.

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11
Q

protoplastic astrocyte

A

capillary processes; heavily stained with GFAP

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12
Q
A

astrocyte stained for GFAP

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13
Q

(cells around neuron)

A

oligodendrocytes; myelinate CNS; smalelr, rounder, darker nucleus than astro; 2-3 normally found around neuron (excess is perineuronal satellitosis)

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14
Q
A

ependymal cells. glial-derived epithelium lining ventricles and spinal canal. no basement membrane. absorptive/secretory/propulsive functions

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15
Q
A

choroid plexus. gilal-derived secretory epithelium; long microvilli with few cells. many mitochondria, golgi, and basal nuclei

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16
Q

layers of neocortex and motor/sensory attributes

A

molecular (mostly pi), ext granular, ext pyramidal, int granular, int pyramidal, plexiform. motor areas are thicker, pyramidals more prominant in motor areas vs sensory.

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17
Q
A

red neurons. response to ischemic injury (12-24 hrs). shrunken soma, eosinophilia, loss of Nissl. nuclei often darker w/o nucleolus.

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18
Q
A

lipofuscin. normal age-related process of oxidized fatty acid accumulation. don’t confuse with SN, DMX, or locus ceruleus of rostral pons (pigmented areas)

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19
Q
A

flame-shaped cytoplasmic inclusions = neurofibrillary tangle in AD

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20
Q
A

Lewy Body inclusions

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21
Q

gliosis

A

common response to diverse injury. Astrocyte hypertrophy and hyperplasia. increased GFAP, larger cytoplasm

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22
Q

Routes of pathogen entry to CNS

A

Hematogenous, local extension (paranasal sinus, middle ear), retrograde transport form PNS, direct implantation (trauma, surgery)

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23
Q

most common predisposing factor to CNS infection

A

immunosuppression!

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24
Q

pachymeningitis

A

infection of dura

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25
encephalitis
inflammation of brain parencyhma with mononuclear cells (usually viral)
26
cerebritis
inflammation of brain parenchyma with PMNs (bacterial)
27
Acute Bacterial Meningitis (Organisms)
Most common CNS infection. (\<6mos: GBS; 6mos-60ys: S pneum, N meningitidis, H flu(less); \>60ys: S pneum, Listeria)
28
Bacterial CNS abscesses (sources, organisms, Sx, imaging, path)
Sources: local or hematogenous (2ndry to septic emboli), S aureus, Strep, polymicrobial, present w/ fever and focal deficits related to localization, ring-enhancing lesion, central liquefaction with fibrotic capsule and mass effect.)
29
Mycobacterial infection of CNS (organism, localization, presentation, path)
TB! (often miliary), TB meningitis affects basal brain with CN involvement, necrotizing granulomas w/ lymphocytes syncytia and fibrosis
30
neurosyphilis
tertiary disease; presents as meningovascular, parenchymal, or tabes dorsalis; immunosuppression increases risk
31
neuroborreliosis
Lyme disease; aseptic lymphocytic meningitis; CNVII palsy; encephalopathyw
32
Asceptic meningitis (organism)
enterovirus in 80%
33
Acute Viral Encephalitis (organisms, path)
Seasonal: Arbovirus; nonseasonal: HSV, Rabies, CMV; path: perivascular inflamm infiltrate, microglial nodules and neuronophagia, intranuclear inclusions
34
hemorrhagic necosis of temporal lobes
HSV1
35
two settings of CNS pathology from CMV
congenital, immunosuppression
36
Fungal CNS infection general manifestations
Diffuse encephalitis, leptomeningitis, space-occupying lesions, septic infarcts, hemorrhages
37
aspergillosis (route, presentation, path)
often hematogenous (ACA, MCA pattern); mimics hemorrhagic infarcts; infiltration of blood vessels by hyphae (silver stain), thrombosis and infarct, variable inflammatory infiltrate.
38
Zygomycosis (presentation, path)
Diabetic ketoacidosis, Rhinocerebral disease; similar to Asper but wider non-septate hyphae
39
Amebic encephalitis (Organism, tropism, path, source)
Naegleria fowleri; frontal hemorrhagic necrosis with cerebral swelling; unicellular organisms in subarachnoid space with vesicular nucleus and prominant nucleolus; from contaminated water
40
cysticercosis
ingestion of contaminated pork, caused by Taenia solium, multiple small disseminated cysts, leading cause of epilepsy
41
CNS infections of immunocompromised host
Crypto meningitis, toxoplasmosis, HIV encephalopathy, progressive multifocal encephalopathy (JC virus)
42
Cryptococcal meningitis (organism, path, presentation)
Crypto neoformans; pseudocystic dilations of V-R space ("bubbles") postivie india ink; variable presentation (slow-evolving with remission/relapse)
43
Toxoplasmosis (type of organism, pattern of infection, path)
obligate intracellular; ring-enhancing brain abscess; best seen with IHC
44
HIV encephalitis (tropism, path)
less common with HAART; subcortical white matter; widespread low-grade inflammation, multinucleated giant cells, patchy demyelination and variable gliosis.
45
Progressive Multifocal Leukoencephalopathy (organism, tropism, path)
JC virus, oligodendroglia, ill-definied demyelinating lesions, lipid-laden macrophages, intranuclear inclusions, bizarre astrocytes
46
early abcess: PMN infiltration
47
late abcess: PMN debris surrounded by fibroblastic collagenous
48
49
Acid-fast stain shows TB organisms
50
microglial nodules (acute viral encephalitis)
51
intranuclear inclusions (acute viral encephalitis)
52
microglial nodule and neuronophagia (acute viral encephalitis)
53
perivascular infiltrate (actue viral encephalitis)
54
aseptic meningitis
55
Negri bodies (circumscribed eosinophilic cytoplasmic inclusions). Rabies
56
cysticercosis (taenia solium). from ingesting eggs. Parenchymal, meningeal, ventricular, spinal (rare) cysts
57
naegleria fowleri. Primary amebic encephalitis. Fulminant, acute meningoencephalitis with swelling, hemorrhagic necrossis of frontal lobes. Path: unicellular organisms with vesicular nucleus in subarachnoid space
58
zygomycosis (mucor). Classically DKA, rhinocerebral disease. wider, non-septate hyphae
59
silver stain of aspergillus (thin, branching hyphae). Infiltrate blood vessels, causing vasculat thrombosis, hemorrhage, infarct with variable inflamm infiltrate. multiple lesions, early resemble hemorrhagic infarct, form abscesses, rarely fibrous ca[sule. Direct seeding of cranial cavity results in chronic, localized ingection with fibrosis/granuloma
60
Glasgow Coma Scale
\<9=severe; 9-12 = Moderate; 13-15 = Minor. Motor is predictive of overall score.
61
management of TBI in the field
Stabilize ASAP (not "scoop and run"). Hypotension/hypoxia bad!
62
Contact Loading TBI
focal injury --\> contusion/hematomas and inertial loading. Animal model: pump fluid into rat brain.
63
Inertial Loading TBI
Results in Diffuse axonal injury (DAI)--most damaging!
64
Molecular/Morphological events after TBI
Necrosis/apoptosis (months); Inflammation (good and bad outcomes); Atrophy (year--cortex and hippocampus CA1)
65
Recovery after TBI
Plasticity (new/stronger synapses) and neurogenesis (hippocampus septal fibers regenerated).
66
Path of DAI
Axonal bulbs/undulations. Stretch injury breaks MTs. primary mechanical damage, 2ndry chemical damage --\> MT catastrophe! --\> relaxation of undulations but transport interruption. Taxol can improve by inhibiting axon degeneration
67
ionic dysregulation in DAI
Massive sodium influx reverse Na-Ca exchanger leading to Ca++ influx. NaCH proteolysis of inactivation gate.
68
repeat TBI
mild DAI (below threshold for Ca++ influx) predisposes to Ca++ influx on repeat injury
69
Imaging for TBI
Diffusion tensor imaging
70
Long-term consequences of TBI
Chronic Traumatic Encephalophaty (after moderate to severe TBI or repetitive mTBI). Amyloid-beta plaques and Neurofibrillary tangles. chronic microgliosis/atrophy of corpus callosum
71
General rules of head trauma
External lesions not a reliable indicator of deeper lesions. Lethal lesions of skull/brain may be small or absent.
72
Linear fracture
contact with flat object...can heal on its own.
73
compound fracture
associated with scalp laceration
74
complex fractures
fracture involving multiple bones of skull
75
depressed fracture
2ndry to small object impact
76
countrecoup Fracture
located distant from point of injury
77
Basal/Hinge Fracture
Serious! associated with occipital impact Hinge: along entire base of skull. Serious trauma
78
Epidural hemorrhage
Between skull and dura. Arterial bleeding. Often temporal bone fracture with middle meningeal artery laceration Results in flat compression of brain and herniation
79
Subdural hemorrhage
caused by motion of brain wrt to skull/dura and tearing of bridging veins typically occurs over cerebral convexities increased risk w/ brain atrophy often accompanied by subarachnoid blood "currant jelly" clot Gray-blue appearance of overlying dura if not evacuated and patient survives, membrane forms...newly formed vessels susceptible to tear
80
Contusion
surface injury to brain
81
laceration
tear of brain
82
Fracture C/L
at site of fracture; tend to be severe
83
Coup contusions
Caused by bending/rebounding of skull at site of injury with or without fracture Moving obhect strujes stationary but movable head
84
Contrecoup contusions
Distant, usually opposite point of impact. 1. Moving head strikes fixed object (eg ground) or 2. Impuslive loading -- Head set in motion or moving head is stopped without being struck or impacted (eg blow to face) Most common in orbito-frontal surfaces and temporal poles
85
Older C/L
golden discoleration (hemosiderin) and tissue retraction. Can cause post-traumatic seizures.
86
Closed Head Injury
Severe angular acceleration forces Pedestrian-bicycle/vehicle impacts, helmeted cyclists, shaken babies Paramedian lesions diffuse axonal injury, concussion, swelling
87
Primary pontine trauma
common after motor vehicle accident ~12 hrs : retraction balls and axonal swelling
88
Abusive trauma in I/C
With/without evidence of trauma with/without fracture of skull or long bones
89
shaken baby trauma
often small SDH spinal cord, root, ganglia trauma corp cllosum transection optic nerve sheath hemorrhages deep galeal or periosteal hemorrhages when head is struck against something
90
Black Brain
total brain necrosis 2ndry to shock and/or severe concussion
91
Chronic infant brain damage
extensive necrosis, white matter, hydrocephalus in child surviving abuse.
92
Choroid Plexus
"Kidney of the brain": tightly regulates CSF composition. highly vascularized fenestrated capillaries --\> ultrafiltrate --\> choroid epithelium (cuboidal glial cells with TJs)
93
CSF composition
much more stable than blood. less amino acids, K+, glucose. Very little protein. low osmolality
94
CSF reabsorption
Pressure gradient drives CSF from ventricles to subarachnoid space. absorbed by arachnoid granulations and villi into superior sagital sinus and spinal veins (possibly by transctosis of large vacuoles)
95
4 physiologic roles of CSF
Physical support--reduces effective weight of brain Protection -- shock absorber supply--brain has strict demands and no supplies Waste removal
96
3 features of brain capillaries that contribute to blood-brain barrier
Tight junctions between non-fenestrated capillary epithelial cells Thick basement membrane astrocyte endfood
97
Two CNS barriers
blood-brain: regulated by capillaries blood-CSF: regulated by choroid plexus
98
BBB restrictions
can cross: uncharged/lipid-soluble molecules, water, some biomolecules (glucose, amino acids, nucleic acid precursers), some drugs can't cross: large charged molecules, many drugs
99
circumventricular organs
not as subject to BBB since have some interaction w/ blood pituitary, pineal, subcommissural organ, etc
100
Lumbar puncture: procedure, contra-indications, complications, gross exam
Subarachnoid space sampling L3/L4 or L4/L5 contra: raised ICP--herniation! Complications: headache gross exam: first vial often bloody (traumatic tap) Cloudy: leukocytosis. bloody: SAH. Orange: high carotine ingestions. Brown: metastatic melanoma. Viscous: metastic mucinous adenocarcinoma. Yellow: billirubin breakdown, remote SAH.
101
CSF lab findings normal vs bacterial vs viral vs fungal meningitis
normal: glucose 60 mg/dL; protein 30 mg/dL Bacterial: Pressure inc, glucose \<40 (PMN metabolism), WBC \>1000 (PMNs), protein \>100 Viral: normal pressure, glucose normal, WBC 10-200 (lymphocytes), protein normal Fungal: variable pressure, glucose \<60, WBC 10-200 (lymphos), protein \>50
102
meningitis Sx
fever, headache, altered mental status, stiff neck, photophobia
103
Bacterial meningitis organisms (by age)
neonates: GBS, E Coli, Listeria Children and aduls: Strep pneum, Neisseria meningitis, H flu \>60 yrs: Strep pneum, Listeria monocytogenes
104
Viral meningitis organisms
Enterovirus: seasonal, carried by kids, fecal-oral or respiratory Herpesviruses: less common but significant morbidity/mortality Arboviruses: RNA viruses spread by arthropods
105
HIV-associated meningitis
Fungal: crypto, coccidioides immitis, histoplasma Bacterial: listeria, treponema pallidum, M TB viral: CMV, VZV
106
means for crossing BBB
Attachment/transcytosis of endothelial cells (bacteria) trojan horse--inside circulating cells diruption of barrier (trauma/surgery)
107
seizure, provoked, unprovoked, epilepsy
seizure: sudden and transient dysfunction of part of brain due to excessive discharge provoked: immediate precipitant (NOT EPILEPSY) unprovoked: no immediate precipitant recurren unprovoked = epilepsy
108
7 classes of CNS tumors
neuroepithelial, cranial/spinal nerves, meninges, lymphomas/haematopoietic, germ cell, sellar tumors, metastatic
109
importance of histological grading of tumors
predicts biological behavior, influences therapy
110
types of neuroepithelial tumors
astrocytoma, oligodendroglioma, ependymoma, embryonal, neurocytoma, mixed neuronal-glial
111
Non-infiltrating astrocytomas
pilocytic astrocytoma: mainly children, rarely progress, better prognosis, 7q34 BRAF mutx plepomorphic xanthoastrocytoma (PXA) subependymal giant cell astrocytoma: only in familiar tumor (tuberos sclerosis)
112
grading of diffuse, infiltrating astrocytomas
Atypia (pleiomorphism, angulated/hyperchromatic nuclei) w/o mitosis = Grade II (diffuse astrocytoma). 75% progression Atypia + mytosis + foci of increased density/pleomorphism = Grade III (anaplastic astrocytoma) . Almost all progress Atypia + mytosis + neovascularization or pseudopallisading necrosis = Grade IV (Glioblastoma)
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diffuse astrocytoma. scattered, pleomorphic, angulated, hypochromatic nuclei w/o mitoses
114
gemistocytic variant diffuse astrocytoma (grade II). plump cells with glassy cytoplasm
115
anaplastic astrocytoma (grade III): atypia + mitoses. foci of increased density/pleomorphism
116
(tumor type and genetics)
glioblastoma (grade IV astrocytoma): high cellularity, atypia, mitoses, areas of necrosis and neovascularization. IDH 1/2 = 2ndry GBM. IDH 1 = better prognosis EGFR = probably primary TP53 = probably secondary
117
(tumor type and genetics)
spony-cystic type pilocytic astrocytoma (non-infiltrating). 7q34 BRAF fusion
118
(tumor type and genetics)
compact type pilocytic astrocytoma (non-infiltrating) with Rosenthal fibers 7q34 BRAF fusion
119
oligodendroglioma (grading, histology, genetics)
highly infiltrating = always grade II fried egg and chicken wire 80% 1p/19q loss of heterozygosity (favorable: respond to chemo/rad)
120
ependymoma (histology, prognosis)
tend to cluster around blood vessels, forming pseudorosettes, prognosis bad for children (brain), OK for adults (spinal)
121
embryonal tumors (demoraphics, grading, most common type)
children, all grade IV--infiltrative/invasive, medulloblastoma most common
122
Medulloblastoma (grading, location, histology, consequences of therapy)
All grade IV, arise from cerebellar vermis, well-circumscribed but invasive, densely-packed cells with round/ovoid nuceli and frequent mitoses; homer-wright rosettes ~40% considered signs of differentiation. neuronal differentiation can be detected with antibody to neurofilament therapy associated with cognitive impairment
123
homer wright rosettes (medulloblastoma--differentiated)
124
dense round/ovoid nuceli = medullablastoma
125
pseudorosettes surrounding blood vessels = ependymoma
126
ependymoma
127
fried egg + chicken wire = oligodendroglioma
128
tumors of cranial and paraspinal nerves (types)
129
Schwannomas
Slow-growing Schwann cell neoplasm. Usually benign but effect CN due to compression (displaces normal elements of the nerve). Most commonly CN VIII, 2nd most common CN V genetics: NF2 --\> bilateral CNVIII schwannoma
130
Neurofibroma
usualy seen with NF1 infiltrate entire nerve, incorporating axons technically benign but hard to treat Dermal--\>nodular lesion of skin
131
meningioma (demographics, cell of incedence, common locations, imaging, histo, immuno)
15% intracranial neoplasms. More common in females, increases with age arise from arachnoid granulations convexity, para-sagittal (falx), sphenoid ridge, sella, etc even enhancement on contrast-MRI transitional: whorls and cords; psammamatous: whols with psammoma bodies (10 ys post-radiation); fibrous stain EMA
132
metastatic CNS tumors (prevalence, common primaries, imaging, prognosis)
15% intracranial neoplasms lung, breast, skin, kidney, colon sometimes (?) ring-enhancing can often be removed, but prognosis depends on location
133
whorls with psammoma bodies = psammomatous meningioma
134
whorls and cords = transitional meningioma
135
General brain tumor incidence
2% malignant neoplasms; 20% in children (2nd to leukemia) bimodal distribution (\<5yo, 45-70 yo) Males: gliomas and embryonal. Females: meningiomas
136
tumor type by age/sex
Males: gliomas and embryonal. Females: meningiomas kids: embryonal/pilocytic astrocytoma 2-34: pituitary and meningioma 34-44: meningioma and nerve sheath 45+: meningioma and GBM
137
etiology of brain tumors
mostly sporadic/unknown \<5% associated with hereditary syndromes: NF1, NF2, tuberous sclerosis ~10 yrs after X-irradiation (meningioma) immunodeficiency pre-disposes (AIDS)
138
Sx of brain tumor
epilepsy (focal or generalized) focal neurologic deficit mental changes (variable depending on location eg apathy/depression for frontal lobes) obstructive hydocephalus --\> headache
139
Sx of Brain tumor due to raised ICP
Headache (postural, nocturnal, early morning) Vomiting (children) Papilledema Clouding of conciousness and coma Can lead to arterial compression, vascular insufficiency, necrosis
140
Herniation sites and consequences
Subfalcine (ACA compression/lhemorrhage) Transtentorial (parahippocampal gyrus)--\>Duret hemorrhages in brainstem ... Uncal if only the anteromedial part of temporal --\> CNIII palsy Tonsillar--\>respiratory arrest
141
ILAE epilespsy classification (4 items)
MEEE: Mode of onset (focal, generalized) Epilepsy syndromes (complex of signs that define a recognizable type) Etiology (genetic, structural/metabolic, unknown) Evolution (Self-limiting, treatment-responsiveness)
142
Generalized seizures
no motor asymmetry--bilateral EEG symetrical rapidly engage bilateral networks (corical, subcortical, both) lots of focal-spreading seizures look generalized diverse: absence, myoclonic, tonic-clonic, tonic, clonic, atonic
143
Focal seizures
Arise within networks limited to one hemisphere, preferential propogation With or without impairment of awareness Can evolve to bilateral convulsive asymmetrical EEG
144
Frontal lobe onset focal seizure
Motor strip-clonic shaking of contra limbs Anterior to motor strip near midline--complex, bilatteral hypermotor activity Broca's -- expressive language dysfunction Fronto-polar -- arrest of activity, hypomotor (can look like absence seizure). Can progress to motor faster than temporal.
145
Temporal lobe onset focal seizure
characteristic look: aura, arrest of activity, unresponsiveness, motor automatisms("pointless fiddling")!!
146
Parietal lobe onset focal seizure
difficult to localize. often clinically silent then present with lobe of propogation
147
Occipital lobe onset focal seizure
Visual signs (positve or negative) often present as temporal
148
Epilepsy etiology
Genetic (presumed or proven) -- often manifest 5-20 yo Structural/metabolic (aquired: stroke, trauma, infection, tumor; developmental: malformations of development) Unknown
149
epilepsy Tx
60% respond to first or second AED. Then surgical assessment or rational duotherapy Different Rx for focal vs general--importance of characterizing!
150
long-term consequences of epilepsy
Even if controlled, comorbid with many psychiatric and social problems--unplanned pregnancy, repeated grades, behavioral problems.
151
general seizure pathophys
disruption of excitiation/inhibition balance increased excitation: mossy fiber sprouting, changes in EAA receptors, presynaptic changes decreased inhibition: GABA receptor, loss of interneurons, change of interneuron activity.
152
epileptogenesis model
insult + genetics/age etc --\> acute damage --\> progressive damage --\> hyperexcitability --\> seizures --\>progressive damage
153
focal seizure pathophys
Paroxysmal depolarization shift sustained repetitive firing mediated by v-gated Na+ channels (can occur w/o Ca++ current)
154
paroxysmal depolarization shift
functional unit of focal seizure prolognue Ca-dependent depolaruzation leading to sodium-mediated action potentials prominant hyperpolarization after due to calcium-dependent K channels
155
Generalized seizure mechanism
disturbance in thalamo-cortical network. T-type / Na+ channel spike-wave pattern.
156
age-related pathophys of seizures
infants are in hyper-excitable state intracellular Cl- is high during development --\> GABA is excitatory (switch from NKCC1 activity to KCC2 changes this) NMDA develop before AMPA GDPs (GABA-mediated)
157
General principles of pharmacological Tx of seizures
treats symptoms, not underlying epileptic condition Does not prevent epilepsy Maximize QOL: minimize seizures and adverse drug effects
158
Types and mechanisms of AEDs
Na+ channel blockers -- block repeptitive firing only. used for focal epilepsies GABA enhancers -- replace "lost" inhibition. Barbituates and benzos Glutamate modulators -- EAA antagonists Ca++ channel blockers -- modulate T-type Ca++ Syaptic transmission modulators -- GABA reuptake inhibitors, GAD activators etc
159
MS definition and presentation
diagnosis of exlusion primary demyelinating disease of CNS characterized by episodic neurological dysfunction and may result in progressive course of defects Problems of white matter tracts -- optic neuritis, UMN weakness/uncoordination, vertigo, speech, gait, bladder spasticity, INO sensory dyesthesia waxing/waning
160
pathogenesis of MS
immune activation of T cells (CD8) in periphery, migration to CNS (molecular mimicry, self antigen) neuroinfalmmation, oligodendrocytes targetted demyelination and axonal degerneration gross brain atrophy
161
general criteria for MS diagnosis
Lesions disseminated in time and space T2/FLAIR hyperintenities and T1 "black holes": subacute/chronic lesions (eg Dawson's Fingers) Gd-enhancing lesions on T1: markers for inflammation and BBB breakdown. acute lesions. Also oligoclonal IgG bands in CSF
162
DMTx for MS
suprression of relapses is goal All act in periphery to prevent CNS entry/activation of T cells and monocytes Tysabri: anti-T cell integrin mab
163
DDx excessive sleepiness
Narcolepsy, sleep apnia, insufficient sleep, medication effect
164
DDx insomnia
Mood disturbance, circadian rhythm disturbance, RLS
165
DDx unusual movement/behavior during sleep
Parasomnia emerging from REM or non-REM sleep, nocturnal seizure, movement disorder
166
Narcolepsy tetrad
hypersomnolence cataplexy hypnogogic/hypnopompic hallucinations sleep paralysis (sleep quality often impaird also)
167
Narcolepsy pathogenesis
deficiency in hypocretin/orexin (responsible for sleep/wake switch)
168
REM sleep behavior disorder
dissociated state: dream enacting behavior, increased tonic or phasic EMG in REM sleep, absence of epileptiform activity
169
REM sleep Behavior Disorder etiology/associations
normally, pon neurons inhibit motor idiopathic, narcolepsy, neurodegenerative (PD, LBD), medications
170
RLS vs PLM
RLS = awake sensory phenomenon with volitional motor response PLM = involuntary sleep-related motor phenomenon most RLS patients have PLM, but not vice-versa
171
RLS pathophys
impairment of dopamine transmission? iron def, pregnancy, renal failure
172
basic biology of circadian clock
SCN = master clock VLPO = switch (inhibits monoamine systems) pineal gland secretes melatonin
173
REM sleep
v different fro SWS. EEG looks almost like awake EEG but muscle atonia
174