Neuro - First Aid Flashcards Preview

► USMLE 1 > Neuro - First Aid > Flashcards

Flashcards in Neuro - First Aid Deck (597):
1

The notochord induces...

overlying ectoderm to differentiate into neuroectoderm and form the neural plate.

2

The neural plate gives rise to...

the neural tube and neural crest cells.

3

The notochord becomes...

nucleus pulposus of the intervertebral disc in adults.

4

The alar plate is...

dorsal/sensory.

5

The basal plate is...

ventral/motor.

6

During development, forebrain/prosencephalon includes...

the telencephalon and diencephalon.

7

Adult derivatives of the telencephalon are...

the cerebral hemispheres and the lateral ventricles.

8

Adult deriatives of the diencephalon are..

the thalamus and third ventricle.

9

During development the midbrain/mesencephalon includes...

the mesencephalon.

10

Adult derivatives of the mesencephalon are...

the midbrain and aqueduct.

11

During development, the hindbrain/rhombencephalon includes..

the metencephalon and the myelencephalon.

12

Adult derivatives of the metencephalon are...

the pons, cerebellum and upper part of the 4th ventricle.

13

Adult derivatives of the myelencephalon are...

the medulla and lower part of the 4th ventricle.

14

Neuroectoderm derivatives (4)

1. CNS neurons 2. ependymal cells 3. oligodendroglia 4. astrocytes

15

Neural crest derivatives (2)

1. PNS neurons 2. Schwann cells

16

Mesoderm derivative (1)

Microglia (like Macrophages, derived from Mesoderm)

17

If neuroporses fail to fuse in the 4th week, there is....

persisten connection between the amniotic cavity and spinal canal. (neural tube defects)

18

Neural tube defects are associated with....

low folic acid intake before conception and during pregnancy.

19

Labs indicative of neural tube defects

-increased alpha-fetoprotein (AFP) -increased AChE in amniotic fluid

20

Spina bifida occulta is due to...

failure of the bony spinal canal to close but there is no structural herniation. The dura is intact.

21

Spina bifida occulta is associated with...

a tuft of hair or skin dimple at the level of bony defect. (usually lower vertebral levels)

22

Meningocele

Meninges (but not spinal cord) herniates through the spinal canal defect; normal AFP.

23

Meningomyelocele

Meninges and spinal cord herniate through spinal canal defect.

24

Anencephaly is...

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

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).