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Flashcards in Steve Nash's Neuro Assists Deck (381)
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1
Q

Where does Herpes labialis go dormant

A

Trigeminal ganglia

HSV-1

2
Q

Where does Herpes genitalis go dormant

A

sacral ganglia

HSV-2

3
Q

Where does Herpes zoster go dormant

A

Dorsal root or trigeminal ganglia

4
Q

Which elements of the neural cytoskeleton form neurofibrillary tangles in alzheimer’s disease

A

Microtubules

5
Q

Notochord induces what

A

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

6
Q

Neural plate gives rise to the

A

neural tube and neural crest cells;

7
Q

Notochord becomes what

A

Notochord becomes nucleus pulposus of the intervertebral disc in adults;

8
Q

Alar plate

A

Dorsal spinal cord;

gives to sensory

9
Q

Basal plate

A

Ventral spinal cord;

Gives rise to motor

10
Q

Prosencephalon develops into

A

Telencephalon and diencephalon;

11
Q

Mesencephalon develops into

A

Mesencephalon;

12
Q

Rhombencephalon develops into

A

Metencephalon and myelencephalon;

13
Q

Telencephalon gives rise to

A

Cerebral hemispheres;

Lateral ventricles

14
Q

Diencephalon gives rise to

A

Thalamus;

Third ventricles

15
Q

Mesencephalon gives rise to

A

Midbrain;

Aqueduct

16
Q

Metencephalon gives rise to

A

Pons and cerebellum;

Upper part of fourth ventricle

17
Q

Myelencehalon gives rise to

A

Medulla;

Lower part of fourth ventricle

18
Q

In the brain, what does the neuroectoderm give rise to

A

CNS neurons;
ependymal cells (inner lining of ventricles, make CSF);
oligodendroglia;
astrocytes

19
Q

In the nervous system, what does the neural crest give rise to

A

PNS neurons;

Schwann cells

20
Q

In the nervous system, what does the mesoderm give rise to

A

Microglia (like macrophages, originate from mesoderm)

21
Q

Neural tube defects: when do they happen, what are the findings

A

neuropores fail to fuse (4th week);
Elevated alpha fetoprotein (AFP) in amniotic and maternal serum;
increased AChE in amniotic fluid confirms (fetal AChE in CSF transudates across defect into amniotic fluid)

22
Q

Spina bifida occulta

A

Failure of bony spinal canal to close, but no structural herniation;
Dura is intact;
associated with tuft of hair or skin dimple at level of bony defect

23
Q

Meningocele

A

Meninges (but not the spinal cord) herniate through spinal canal;
normal AFP

24
Q

Meningomyelocele

A

Meninges and spinal cord herniate through spinal canal defect

25
Q

Spina bifida with myeloschisis

A

Spinal cord visibly seen;

increased AFP

26
Q

Anencephaly

A

Malformation of the anterior neural tube resulting in no forebrain, open calvarium (frog like appearance);
Findings: increased AFP, polyhydramnios (no swallowing);
associated with maternal diabetes type I;
maternal folate intake decreases chances

27
Q

Holoprosencephaly

A

Failure of left and right hemispheres to separate;
Usually occurs during weeks 5 and 6;
complex multifactorial etiology that may be related to mutations in sonic hedgehog signaling pathway;
Moderate form has cleft lip/palate, most sever form results in cyclopia;
Associated with Patau

28
Q

Lissencephaly

A

smooth brain with no gyri;
lack of hemisphere sulci;
severe neurologic impairment

29
Q

Chiari II (arnold chiari malformation)

A

Significant herniation of cerebellar tonsils and vermis through foramen magnum with aquaductal stenosis and hydrocephalus;
Often presents with lumbrosacral myelomeningiocele and paralysis below the defect

30
Q

Dandy Walker

A

Agenesis of cerebellar vermis and cystic enlargement of 4th ventricle (fills the enlarged posterior fossa);
Associated with hydrocephalus and spina bifida;

31
Q

Chiari I malformation

A

Usually seen in adults;
less significant herniation of cerebellar tonsils into magnum foramen;
Valsalva makes worse;
Usually asymptomatic

32
Q

Syringomyelia

A

Cystic cavity (syrinx) within the spinal cord (if central then it is called hydromyelia);
Crossing anterior spinal commissural fibers are typically damaged first leading to cape like bilateral loss of pain and temperature sensation in upper extremities;
Mostly at C8 T1 level;
Associated with Chiari 1 malformation;

33
Q

Tongue development

A

1st and 2nd branchial arches form the anterior 2/3 (taste is CN 7 and sensation is CN V3);
3rd and 4th give rise to posterior 1/3 (taste and sensation is CN 9, very posterior taste is 10);
motor is CN12;
Muscles of the tongue are derived from occipital myotomes

34
Q

Stain used for neurons

A

Nissl Substance (Stains RER, which is only present in dendrites and cell bodies, NOT axons)

35
Q

If an axon is injured it undergoes what

A

Wallerian degeneration;
degeneration distal to injury and axonal retraction proximally;
allows for potential regeneration of axon if in PNS (CNS will never regenerate unless it is the olfactory nerve)

36
Q

Astrocyte

A

Physical support, repair, K metabolism, removal of excess neurotransmitter, foot process are component of the BBB, glycogen fuel reserve buffer;
Reactive gliosis in response to neural injury;
Astrocyte marker is GFAP;
Derived from neuroectoderm

37
Q

Microglia

A

CNS phagocytes;
derived from bone marrow bone monocytes (mesodermal origin);
not readily seen in Nissl stains;
Have small irregular nuclei and relatively little cytoplasm;
Scavenger cells of CNS;
respond to tissue damage by differentiating into large phagocytic cells;
Is an Antigen presenting cell;
Secretes free radicals;
HIV infected microglia fuse to form multi-nucleated giant cells

38
Q

Oligodendroglia

A

Myelinates neurons of the CNS;
1 oligodendroglia can myleniated around 30 to 50 nerves;
Derived from neuroectoderm;
fried egg appearance;
MS, progeressive multifocal leukoencephalopathy, and leukodystrophies attacks this cell type;

39
Q

Glial cells

A

Supporting cells of the CNS;

capable of cell division

40
Q

Schwann cells

A

myelinates PNS in a 1:1 ratio;
promotes axonal regeneration;
Derived from neural crest;
destroyed in Guillain-Barre;

41
Q

Acoustic neuroma

A

type of schwannoma;
Typically located in internal acoustic meatus (CN 8);
If bilateral think NF2 (on gene 22, affecting 2 ears)

42
Q

Sensory: Free nerve endings

A

C fibers: slow unmyelinated fibers;
A delta fibers: fast, myelinated fibers;
Located on all skin;
conveys pain and temperature

43
Q

Sensory: Meissner corpuscles

A

Large, myelinated, and adapt quickly;
Found in glabrous (hairless) skin;
Senses dynamic, fine/light touch and position sense

44
Q

Sensory: Pacinian corpuscles

A

Large, myelinated and adapt quickly;
Found in Deep skin layers, ligaments, and joints;
Senses vibration and pressure sensation

45
Q

Sensory Merkel discs

A

Large, myelinated and adapt slowly;
Found in the basal epidermal layer and in hair follicles;
Sense pressure, deep static touch (e.g. shapes, edges), and position sense

46
Q

What are the different layers/parts to a peripheral nerve and important info about them

A

Endoneurium- invests single nerve fiber layers (inflammatory infiltrate in guillain Barre syndrome);
Perineurium (permeability barrier)- surrounds a fascicle of nerve fibers, must be rejoined in microsurgery for limb reattachment;
Epineurium- dense connective tissue that surrounds entire nerve (fascicle and bleed vessels)

47
Q

Ependymal cells

A

Line ventricles of brain;
some differentiate into choroid epithelial cells;
cilia assist in CSF circulation

48
Q

Tanycytes

A

Specialized type of ependymal cells;
basal cytoplasmic processes contact CNS blood;
thought to aid in blood-CSF transport

49
Q

NE: where is it made, what disorders alter its levels

A

Made in Locus Ceruleus in pons;
increased in anxiety;
decreased in depression

50
Q

Dopamine: where is it made, what disorders alter its levels

A

Made in ventral tegmentum and SNc (midbrain);
increased in Huntington;
decreased in Parkinson;
Decreased in Depression

51
Q

5-HT: where is it made, what disorders alter its levels

A

Made in Raphe nucleus (pons, medulla, midbrain);
Increased in parkinson;
decreased in anxiety;
decreased in depression

52
Q

ACh: where is it made, what disorders alter its levels

A

Made in basal nucleus of Meynert;
Increased in Parkinson;
decreased in Alzheimer;
Decreased in Huntingtons

53
Q

GABA: where is it made, what disorders alter its levels

A

Decreased in Anxiety;
Decreased in Huntington;
Made in nucleus Accumbens

54
Q

Locus ceruleus is activated by what emotion

A

stress and panic

55
Q

Nucleus Accumbens and septal nucleus are know for being what

A

the reward center, pleasure, addiction, and fear

56
Q

Blood-Brain Barrier: made from

A

Foot process of astrocytes, tight junctions in non fenestrated capillary endothelial cells, and a Basement membrane;

57
Q

Blood-Brain Barrier: what crosses it

A

Glucose and amino acids cross slowly via carrier mediated transport;
Nonpolar/lipid soluble cross rapidly via diffusion;
Area postrema has no BBB (vomiting center, OVLT-osmotic sensing);

58
Q

Function of Hypothalamus

A
Hypothalamus wears TAN HATS;
Thirst and water balance;
Adenohypophysis control (regulates anterior pituitary),
Neurohypophysis releases hormones produced in the hypothalamus;
Hunger;
Autonomic Regulation;
Temperature Control;
Sexual urges
59
Q

what is the OVLT

A

Part of hypothalamus;
not covered by BBB;
Organum vasculosum of the lamina terminalis-senses change in osmolarity)

60
Q

Area postrema responds to

A

responds to emetics

61
Q

What nucleus makes ADH

A

Supraoptic nucleus

62
Q

What nucleus makes oxytocin

A

Paraventricular nucleus

63
Q

Lateral area of the hypothalamus

A

Hunger;
Destruction leads to anorexia and failure to thrive in kids;
Inhibited by leptin;
If you zap you lateral nucleus you shrink laterally

64
Q

Ventromedial area of the hypothalamus

A

Satiety;
Destruction (e.g. craniopharyngioma) leads to hyperphagia;
stimulated by leptin;
If you zap your ventromedial nucleus, you grow ventrally and medially

65
Q

Anterior hypothalamus

A

Cooling and parasympathetics;

Anterior Nucleus=Cooling off (A/C=anterior cooling)

66
Q

Posterior hypothalamus

A

Heating, sympathetics;

Posterior nucleus=get fired up (heating and parasympathetics)

67
Q

Suprachiasmatic nucleus of the hypothalamus

A

Circadian rhythm;
SCN releases NE on the pineal gland leading to melatonin;
SCN responds to light (or lack there of)

68
Q

Rapid Eye movement in REM sleep is caused by the

A

PPRF paramedian Pontine Reticular Formation

69
Q

Drugs that decrease REM

A

Alcohol, Benzodiazepines, and barbiturates all decrease REM and delta wave sleep as well;
NE also decreases REM

70
Q

How do you treat enuresis

A

bedwetting treated with oral desmopressin acetate (DDAVP), which mimics ADH;
Preferred over imipramine due to side effects

71
Q

What can treat night terrors and sleep walking

A

Benzodiazepines

72
Q

Awake (eyes open) what is the EEG look like

A

Beta waves (highest frequency, lowest amplitude)

73
Q

What is the EEG look like in Awake stage with eyes closed

A

Alpha waves

74
Q

Stage N1 of sleep

A

light sleep, theta wave

75
Q

Stage N2 of sleep

A

Deeper sleep;
when bruxism occurs;
Sleep spindles and K complexes

76
Q

Stage N3 of sleep

A

Deepest sleep that is non-REM;
sleepwalking, night terrors, and bedwetting occur;
delta waves (lowest frequency, highest amplitude)

77
Q

REM sleep

A
Loss of motor tone, increased Brain O2 usage, increase and variable pulse and blood pressure;
When dreaming and penile/clitoral tumescence occur;
may serve a memory processing function;
Beta waves (live awake with eyes open stage)
78
Q

Posterior pituitary

A

Receives hypothalamic axonal projections from supraoptic (ADH) and paraventricular (oxytocin) nuclei;

79
Q

input, information, destination of the VPL of the thalamus

A

Input is the spinothalamic and dorsal column/medial lemniscus;
Info is pain and temp, pressure, touch, vibration and proprioception;
destination is the primary somatosensory cortex

80
Q

input, information, destination of the VPM

A

Trigeminal and gustatory pathway;
info is Face sensation and taste;
destination is the primary somatosensory cortex;
Makeup goes on the FACE (vpM)

81
Q

input, information, destination of the LGN

A

Input is CNII;
Info is vision;
destination is the Calcarine sulcus;
Lateral=Light

82
Q

input, information, destination of the MGN

A

input is the Superior olive and inferior colliculus of tectum;
info is hearing;
Destination is the auditory cortex of the temporal lobe;
Medial=music

83
Q

input, information, destination of the VL

A

Input is the basal ganglia and cerebellum;
Info is motor;
Destination is the Motor Cortex

84
Q

Limbic system

A

Involved in emotion, long-term memory, olfaction, behavior modification, and autonomic nervous system function;
Structures include hippocampus, amygdala, fornix, mammillary bodies, and cingulate gyrus;
5 F’s-Feeding, Fleeing, Fighting, Feeling, Sex

85
Q

Cerebellum

A

Aids in coordination and balance;
Control ipsilateral side (outputs go to contralateral motor cortex, then that crosses when going down the corticospinal tract)

86
Q

Inputs into the Cerebellum

A

Contralateral cortex via the middle cerebellar peduncle;
Ipsilateral proprioceptive information via inferior cerebellar peduncle from the spinal cord (inputs nerves=climbing and mossy fibers)

87
Q

Outputs from the Cerebellum

A

Sends info to contralateral vortex to modulate movement;
Output is the purkinje cells to the deep nuclei of the cerebellum to the contralateral cortex via the superior cerebellar peduncle;

88
Q

What are the deep nuclei of the Cerebellum

A

Lateral to medial they are the Dentate, Emboliform, Globose, Fastigial (don’t eat greasy foods);

89
Q

Lateral lesions in the Cerebellum

A

Voluntary movement of the extremities;

when injured, you tend to fall toward injured (ipsilateral) side

90
Q

Medial lesions in the cerebellum

A

Lesions involve midline structures (vermal cortex, fastigial nuclei) and/or the flocculonodular lobe result in truncal ataxia, nystagmus, and head tilting;
These patients also may have a wide-based gait and deficits in truncal coordination;
Usually midline lesions result in bilateral motor deficits in axial and proximal limb muscles

91
Q

What does dopamine do in the basal ganglia

A

Binds D1 in the excitatory pathway, and to D2 in the inhibitory pathway which leads to increased motion

92
Q

Parkinson Disease

A

Degenerative disorder of CNS associated with Lewy Bodies (composed of alpha-synuclein- intracellular eosinophilic inclusion) and loss of dopaminergic neurons (i.e. depigmentation) of the substantia nigra pars compacta

93
Q

Huntington Disease

A

Autosomal dominant trinucleotide repeat (CAG) disorder on chromosome 4;
symptoms manifest between 20 and 40;
Choreiform movements, aggression, depression, dementia;
Decreased levels of GABA and ACh in the brain;
Neuronal death via NMDA-R binding and glutamate toxicity;
Atrophy of the caudate nuclie can be seen on imaging;
CAG=Caudate loses Ach and Gaba

94
Q

Hemiballismus

A

Sudden, wild flailing of 1 arm with or without leg;

Contralateral subthalamic nucleus injury (e.g. lacunar infarct);

95
Q

Chorea

A

Sudden, jerky, purposeless movements;

Lesion in the basal ganglia (think Huntington)

96
Q

Athetosis

A

Slow, writhing movements, especially seen in fingers;

lesion to the basal ganglia (think Huntington)

97
Q

Myoclonus

A

Sudden, brief, uncontrolled muscle contraction;
Jerks, hiccups;
Common in metabolic abnormalities such as renal and liver failure

98
Q

Dystonia

A

Sustained, involuntary muscle contractions;
Writer’s cramp;
blepharospasm (sustained eyelid twitch)

99
Q

Essential tremor

A

Action tremor; exacerbated by holding posture/limb position;
Genetic predisposition;
Patients often self-medicated with EtOH, which decreases tremor amplitude;
Treat using beta blockers, primidone

100
Q

Resting tremor

A

Uncontrolled movement of distal appendages (most noticeable in hands);
tremor goes away with purposeful movement;
Think Parkinson disease;

101
Q

Intention tremor

A

Slow, zigzag motion when pointing/extending arm towards target;
Cerebellar dysfunction

102
Q

Internal Capsule: what are the 3 areas and what 3 tracts go through each

A

Anterior Limb that carries the Frontopontine and thalamicortico fibers;
Genu which carries the Corticobulbar fibers;
Posterior limb which carries the Corticospinal and some corticobulbar tracts

103
Q

Lesion to the amygdala

A

Kluver-Bucy Syndrome (hyperorality, hypersexuality, disinhibited behavior);
Associated with HSV-1 infection

104
Q

Lesion to the Frontal lobe

A

Disinhibition and deficits in concentration, orientation, and judgment;
May have reemergence of primitive reflexes

105
Q

Lesion to the Right parietal-temporal cortex

A

Spatial neglect syndrome (agnosia of the contralateral side of the world);
This is the non-dominant side in most people

106
Q

Lesion to the left parietal-temporal cortex

A

Agraphia, acalculia, finger agnosia, and left-right disorientation;
Called Gerstmann syndrome

107
Q

Lesion to the Reticular activating system

A

found in the midbrain;

Reduced levels of arousal and wakefullness (e.g. coma)

108
Q

Lesion to the Mammilary bodies

A

Wernicke-Korsakoff syndrome;
Confusion, opthalmoplegia, ataxia;
memory loss (anterograde and retrograde amnesia), confabulation, personality changes;
associated with thiamine B1 deficiency, EtOH abuse;
can be precipitated by giving glucose to a B1 deficient patient;
Wernicke likes a CAN of beer (Confusion, Ataxia, Nystagmus)

109
Q

Lesion to the basal ganglia

A

May result in tremor at rest, chorea, or athetosis;

Think Parkinson

110
Q

Lesion to the Cerebellar hemispheres

A

Intention tremor, limb ataxia, and loss of balance;
damage to the cerebellum leads to ipsilateral deficits;
Fall toward side of lesion;
Cerebellar hemispheres are lateral and affect lateral limbs

111
Q

Lesion to the cerebellar vermis

A

Truncal ataxia;
Dysarthria;
Vermis is medial so it affects medial structures

112
Q

Lesion to the Subthalamic nucleus

A

Get a contralateral hemiballismus

113
Q

Lesion to the bilateral hippocampus

A

Anterograde amnesia-inability to make new memories

114
Q

Lesion to the Paramedian Pontine Reticular Formation

A

Eyes look away from side of lesion

115
Q

Lesion to the Frontal Eye Fields

A

Eyes look toward the side of lesion

116
Q

Lesion to the temporo-occipital association cortex

A

Get visual agnosia (see an object, but you can’t recognize it)

117
Q

Central Pontine Myelinolysis

A

A variant of osmotic demyelination syndrome;
Acute paralysis, dysarthria, dysphagia, diplopia, and loss of consciousness;
Can cause locked in syndrome;
Massive axonal demyelination in pontine white matter tracts secondary to osmotic forces and edema;
Usually caused by overly rapid correction of hyponatremia;
From low to high you pons will die, from high to low your brain will blow (cerebellar edema/herniation)

118
Q

Aphasia

A

Higher order inability to speak

119
Q

Dysarthria

A

motor inability to speak

120
Q

Broca aphasia

A

non-fluent aphasia with intact comprehension;
broca area is in the inferior frontal gyrus of frontal lobe;
Broca Broken Boca (mouth in spanish)

121
Q

Wernicke aphasia

A

Fluent aphasia with impaired comprehension and repetition;
Wernicke area is in the superior temporal gyrus of temporal lobe;
Wernicke is Wordy by makes no sense

122
Q

Global aphasia

A

Non-fluent with impaired comprehension;

both broca and wernicke areas affected

123
Q

Conduction aphasia

A

Poor repetition but fluent speech and intact comprehension;
Can be caused by damage to the superior temporal gyrus and/or left supramarginal gyrus;
Can’t repeat phrases

124
Q

Transcortical motor aphasia

A

Non-fluent aphasia with good comprehension and repetition

125
Q

Transcortical sensory aphasia

A

Poor comprehension with fluent speech and repetition

126
Q

Mixed transcortical aphasia

A

non-fluent speech, poor comprehension, good repetition

127
Q

Middle Cerebral Artery lesions can affect what areas

A
Motor cortex (contralateral upper limb and face paralysis);
Sensory cortex (contralateral loss of sensation of upper and lower limbs and face);
Temporal lobe (Wernicke and Broca; See aphasia if dominant side (left), See hemineglect if lesion is nondominant (right) side)
128
Q

Anterior Cerebral Artery lesion can affect what areas

A
Motor cortex (lower limb contralateral paralysis);
Sensory Cortex (Contralateral lower limb loss of sensation)
129
Q

Lenticulo-Striate Artery lesion can affect what areas

A

Striatum and internal capsule (contralateral hemiparesis/hemiplegia)

130
Q

Anterior spinal artery lesion can affect what areas

A
Lateral corticospinal tract (contralateral hemiparesis of upper and lower limbs;
Medial lemniscus (decreased contralateral proprioception);
Caudal medulla/hypoglossal nerve (ipsilateral hypoglossal dysfunction and tongue deviates ipsilaterally)
131
Q

Medial Medullary Syndrome

A

Caused by infarct of paramedian branches of the ASA and vertebral arteries;

132
Q

Posterior Inferior Cerebellar Artery lesion affects what areas

A

Lateral Medullary (Wallenberg) syndrome
Lateral medulla;
Vestibular nuclei (vomiting, vertigo, nystagmus);
Lateral spinothalamic and spinal trigeminal nucleus (decreased pain and temp from ipsilateral face and contralateral body);
Nucleus ambiguus (dysphagia, hoarsenss, decreased gag reflex);
Sympathetic fibers (ipsilateral horners syndrome);
Inferior cerebellar peduncle (ataxia, dysmetria)

133
Q

Anterior inferior Cerebellar artery lesion affects what areas

A

Lateral pontine syndrome;
Facial nucleus are specific to AICA;
Lateral pons, cranial nerve nuclei, vestibular nuclei, facial nucleus, spinal trigeminal nucleus, cochlear nuclei, sympathetic fibers;
Symptoms are vomiting, vertigo, nystagmus, Paralysis of the face, decreased lacrimation and salvation, decreased taste from ant. 2/3 tongue, decreased corneal reflex, decreased facial pain and temp, ipsilateral decreased hearing, ipsilateral horners ,ataxia and dysmetria

134
Q

Posterior Cerebral Artery lesion affects what

A

Occipital cortex and visual cortex;

contralateral hemianopia with macular sparing (visual acuity is fine, but decreased visual field)

135
Q

Basilar artery lesion affects what areas

A

Pons, medulla, lower midbrain, corticospinal and corticobulbar tracts, ocular cranial nerve nuclei, PPRF;
Symptoms are preserved consciousness and blinking with quadraplegia, loss of voluntary facial, mouth, and tongue movements (locked in syndrome where you can do vertical eye movements and blink)

136
Q

Anterior Communicating artery lesion

A

Most common lesion in aneurysm;
can lead to stroke;
Saccular (berry) aneurysm can impinge cranial nerves;
Symptoms are visual field defects;
Lesions are typically aneurysms not strokes!

137
Q

Posterior Communicating artery lesions

A

Common site for saccular aneurysms;
CN III palsy where eye is down and out with ptosis and pupil dilation;
Lesions are typically aneurysms not strokes!

138
Q

Berry Aneurysms

A

Occur at bifurcations in the circle of willis;
Mostly at the junction of the Acom and ACA;
Rupture leads to subarachnoid hemorrhage (worst headache ever) or hemorrhagic stroke;
can compress optic chiasm;
Associated with ADPKD, Ehlers-Danlos, Marfan;
Risk factors are old age, HTN, smoking, being black

139
Q

Charcot-Bouchard microaneurysm

A

Associated with chronic HTN;

affects small vessels (mostly basal ganglia and thalamus)

140
Q

Central post stroke pain syndrome

A

Neuropathic pain due to thalamic lesions;
Initial sensation of numbness and tingling followed by weeks to months of allodynia (normal stimuli cause pain) and dysaesthesia;
occurs in 10% of stroke patients

141
Q

Epidural Hematoma

A

Rupture of the middle meningeal artery (branch of the maxillary artery), often secondary to fracture of the temporal bone;
Lucid Interval;
Rapid expansion of blood since it is arterial leading to transtentorial herniation and CN III palsy;
CT shows lens like lesions, hyperdense blood collection that does NOT cross suture lines (Can cross falx, tentorium)

142
Q

Subdural Hematoma

A

Snaking Subdural;
Rupture of bridging veins;
slow venous bleeding so it takes longer;
seen in elderly individuals, alcoholics, blunt trauma, shaken baby;
Can cross suture lines but cannot cross falx or tentorium

143
Q

Subarachnoid hemorrhage

A

Rupture of an aneurysm or an AVM;
rapid time course;
Patient complains of worst headache of my life;
bloody or yellow (xanthochromic) spinal tap;
2-3 days afterward, risk of vasospasm due to blood breakdown (not visible on CT, treat with nimodipine) and rebleeding (seen on CT)

144
Q

Intraparenchymal hemorrhage

A

AKA Hypertensive hemorrhage;
Most commonly caused by systemic HTN;
Also seen with amyloid angiopathy, vasculitis, and neoplasm;
Typically occurs in the basal ganglia and internal capsule (charcot-bouchard aneurysm of lenticulostriate vessels), but can be lobar

145
Q

What is the time table of histologic events after a ischemic stroke

A

12-48 hours you get Red neurons;
24-72 hours you get necrosis + neutrophils;
3-5 days you get macrophages;
1-2 weeks you get reactive gliosis + vascular proliferation;
>2 weeks you get glial scars

146
Q

Ischemic stroke: what areas are susceptible to damage

A

irreversible damage starts at 5 minutes;

most vulnerable areas are the hippocampus, neocortex, cerebellum, watershed areas;

147
Q

Hemorrhagic stroke

A

Intracerebral bleeding, often due to HTN, anticoagulation, and cancer (abnormal vessels can bleed);
may be secondary to ischemic stroke followed by reperfusion (increased vessel fragility);
Basal ganglia are most common site of intracerebral hemorrhage

148
Q

Ischemic Stroke: what is it

A

Acute blockage of vessels leading to disruption of blood flow causing ischemia;
results in liquefactive necrosis;

149
Q

How do you treat ischemic strokes

A

Treatment- tPA (if within 3 to 4.5 hr of onset and no hemorrhage/risk of hemorrhage). Reduced risk with medical therapy (e.g. aspirin, clopidogrel)

150
Q

What are the types of ischemic strokes

A

1) Thrombotic-due to a clot forming directly at the site of infarct (commonly at MCA);
2) Embolic-an embolus from another part of the body obstructs a vessel, can affect multiple vascular territories, often cardioembolic;
3) Hypoxic-due to hypoperfusion or hypoxemia, common during cardiovascular surgery, tends to affect watershed areas;

151
Q

Transient ischemic attacks

A

Brief, reversible episode of focal neurologic dysfunction

152
Q

Ventricular system: the flow of CSF

A

Lateral ventricle dumps into the 3rd ventricle via right and left interventricular foramina of Monro;
3rd vent. dumps into 4th vent via cerebral aqueduct of Sylvius;
4th dumps in to subarachnoid space via 2 foramina of Luschka (Lateral) and 1 foramen of Magendie=Medial;

153
Q

How is CSF made and reabsorbed

A

Made by the ependymal cells of the choroid plexus;

reabsorbed by arachnoid granulations in the superior sagittal sinus

154
Q

Communicating Hydrocephalus

A

decreased CSF absorption by arachnoid granulations, which can lead to increased intracranial pressure, papilledema, and herniation (e.g. arachnoid scarring post meningitis)

155
Q

Normal pressure hydrocephalus

A

Does not result in increased subarachnoid space volume;
Expansion of ventricles distorts the fibers of the corona radiata and leads to clinical triad of urinary incontinence, ataxia, and cognitive dysfunction (wet, wobbly, and wacky);
treat with ventricle shunt

156
Q

Hydrocephalus ex vacuo

A

Appearance of increased CSF in atrophy (Alz, advanced HIV, Huntington, Pick disease);
Intracranial pressure is normal;
triad not seen;
Apparent increase in CSF observed in imaging is actually result of decreased neural tissue due to atrophy

157
Q

Noncommunicating hydrocephalus

A

Caused by structural blockage of CSF circulating within the ventricular system (e.g. stenosis of the aqueduct of Sylvius) leading to increased intracranial pressure leading to bilateral papilladema, nausea/vomiting, nuchal rigidity, mental status change

158
Q

How many spinal nerves do we have

A

31 spinal nerves;
8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal;
C1-C7 exit at corresponding vertebra, all others go out one vertebra below

159
Q

Vertebral disc herniation

A
Nucleus pulposus (soft central disc) herniates though the annulus fibrosus (outer ring);
usually occurs posterolaterally at L4-L5 or L5-S1
160
Q

Dorsal column sense what

A

sends ascending pressure, vibration, fine touch, and proprioception;

161
Q

Dorsal column first order neurons

A

1st order neurons: sensory nerve endings to the cell bodies in the dorsal root ganglia, enters the spinal cord, ascends ipsilaterally in dorsal column;
1st synapse: ipsilateral cuneatus (upper body, arms) or gracilis (lower body, legs) in medulla

162
Q

Dorsal column second and third order neurons

A

from ipsilateral cuneatus (upper body, arms) or gracilis (lower body, legs) it decussates in medulla then ascends contralaterally in medial lemniscus;
second synapse is in the VPL of the thalamus;
3rd order neuron goes to sensory cortex

163
Q

Spinothalamic tract: senses what

A

Sends ascending-lateral: pain, tempurature and medial: crude touch and pressure;

164
Q

Spinothalamic tract: 1st order neurons

A

1st order neurons are sensory nerve endings (Adelta and C fibers) to the cell body in dorsal root ganglia where it enters the spinal cord;
1 synapse is in the ipsilateral gray matter of the spinal cord (dorsal horn)

165
Q

Spinothalamic tract: 2nd order neurons

A

from the synapse in the ipsilateral dorsal horn the 2nd order neuron decussates at the anterior white commissure and ascends contralaterally to the VPL thalamus where it synapses and a 3rd order neuron goes to the sensory cortex

166
Q

Lateral corticospinal tract: sends what

A

Sends descending voluntary movement of contralateral limbs

167
Q

Lateral corticospinal tract: first order neurons

A

UMN: cell body in primary motor cortex where it descends ipsilaterally (through internal capsule), most fibers decussate at caudal medulla (pyramidal decussation) where it descends contralaterally;
First synapse is in the cell body of the anterior horn in the spinal cord

168
Q

Lateral corticospinal tract: second order neurons

A

from the anterior horn the LMN (2nd order) leaves the spinal cord and goes to the NMJ

169
Q

Romberg test looks at what

A

unconscious proprioception;

tests the spinocerebellar and dorsal column pathways

170
Q

Multiple sclerosis is destruction of what in the spinal cord

A

Due to demyelination;
mostly white matter of cervical region;
random and asymmetric lesions, due to demyelination;
scanning speech, intention tremor, nystagmus

171
Q

Amyotrophic lateral sclerosis: is damage to what

A

Combined UMN and LMN deficits with NO sensory, cognitive, or oculomotor deficits;
Can be caused by defect in superoxide dismutase 1;
Commonly presents as fasciculations with eventual atrophy and weakness of hands;
fatal;
RiLUzole (Lou Gerhrig) is given to decrease presynaptic glutamate release;

172
Q

Complete occlusion of the anterior spinal artery damages what parts of the spinal cord

A

Spares the dorsal columns and lissauer tract;
Every other tract is lesioned at and below the area of the occlusion;
The upper thoracic ASA territory is a watershed area, as artery of Adamkiewicz supplies ASA below T8

173
Q

Tabes dorsalis affects what

A

Caused by tertiary syphilis;
Results from degeneration (demyelination) of dorsal columns and roots leading to impaired sensation and proprioception and progressive sensory ataxia leading to poor coordination;
associated with Charcot joints, shooting pain, Argyll Robertson pupils;
See absent DTRs and + romberg

174
Q

Syringomyelia

A

Syrinx expands and damages anterior white commissure of spinothalamic tract (2nd order neurons) leading to bilateral loss of pain and temp sensation (usually C8 to T1);
Seen with Chiari 1 malformations;
can expand and affect other tracts

175
Q

Vitamin B12 or Vitamin E deficiency leads to problems with what parts of the spinal cord

A

Get subacute combined degeneration which is demyelination of dorsal columns, lateral corticospinal tracts, and spinocerebellar tracts;
see ataxic gate, paresthesia, impaired position and vibration sense

176
Q

Poliomyelitis;

A

Cause by polio virus (Fecal-oral);
replicates in the oropharynx and small intestine before spreading via blood to the CNS;
Infection causes destruction of cells in the anterior horn of the spinal cord (death of LMNs);
Symptoms are LMN signs and general infection signs;
Findings: CSF with increased WBCs and slight increase of protein (no glucose change);
Virus can be found in stool or throat;

177
Q

Werdnig Hoffmann Disease

A

AKA spinal muscular atrophy;
Congenital degeneration of the anterior horns of the spinal cord leading to LMN lesions;
Floppy baby with marked hypotonia and tongue fasciculations, starts eating then gets tired;
infantile type has median age of death of 7 months (corticobulbar tract damage leads to respiratory failure);
Autosomal recessive

178
Q

Friedreich Ataxia

A

Autosomal recessive trinucleotide repeat disorder (GAA) on chromosome 9 in gene that encodes frataxin (iron binding protein);
leads to impairment in mitochondrial function;
degeneration of multiple spinal tracts leads to muscle weakness and loss of DTRs, vibratory sense, proprioception;
Friedreich is Fratastic (frataxin): he is your favorite FRAT brother, always STUMBLING, STAGGERING, and FALLING, but has a big heart (hypertrophic cardiomyopathy cause of death);
Present in child with kyphoscoliosis

179
Q

Brown Sequard syndrome

A

Hemisection of spinal cord;
Ipsilateral UMN signs below level of the lesion (corticospinal damage);
Ipsilateral loss of tactile, vibration, proprioception sense 1-2 levels below lesion (dorsal column damage);
Contralateral pain and temp loss below level of lesion (spinothalamic damage);
Ipsilateral loss of all sensation at level of lesion;
Ipsilateral LMN at level of lesion;
If at level T1 will get Horners due to damage of the oculosympathetic pathway

180
Q

Horner Syndrome

A

Sympathectomy of face;
Ptosis (slightly drooping eyelid; superior tarsal muscle);
Anhidrosis (absent sweating) and flushing of affected side;
Miosis (pupil constriction);
Associated with lesion at T1;
PAM is horny

181
Q

Track the oculosympathetic pathway

A

starts in hypothalamus descends with 1st neuron to the lateral horn in T1 where it synapses on 2nd order;
2nd order leaves spinal cord and goes to sympathetic chain where it rises to C2 (at bifercation of common carotid) and synapses on 3rd order;
Exits at C2 and innervation of sweat tracts with the external carotid and innervation of eye tracts the internal carotid

182
Q

Notable Dermatomes

A

C2 is back of head (skull cap) but not face;
C3 is the turtleneck;
C4 is the low collar shirt;
T4 is nipples;
T7 is the xiphoid process;
T10 is the umbilicus;
L1 is inguinal ligament;
L4 wraps lateral thigh and covers knee cap;
S2, 3, 4; erection and sensation of penile and anal zones

183
Q

Clinical Reflexes

A
Biceps=C5;
Triceps=C7;
Patella=L4;
Achilles=S1;
Cremaster reflex=L1, L2;
Anal wink=S3, S4
184
Q

Moro reflex

A

Hang on for life reflex;

abduct/extend limbs when startled, and then draw together

185
Q

Rooting reflex

A

Movement of head toward one side if cheek or mouth is stroked;
nipple seeking

186
Q

Sucking reflex

A

sucking response when roof of mouth is touched

187
Q

Palmar reflex

A

Curling of fingers if palm is stroked

188
Q

Galant reflex

A

Stroking along one side of the spine while newborn is face down;
causes lateral flexion of lower body toward stimulated side

189
Q

Pineal gland function

A

Melatonin release;

Circadian rhythms

190
Q

Superior colliculi

A

Conjugate vertical gaze center;

Remember that your eyes are SUPERIOR to your ears

191
Q

Inferior Colliculi

A

Auditory;

Remember that your eyes are SUPERIOR to your ears

192
Q

Parinaud syndrome

A

Paralysis of conjugate vertical gaze due to lesion in superior colliculi (e.g. pinealoma)

193
Q

CN III does what

A
Oculomotor nerve;
Eye movement;
pupillary constriction (sphincter pupillae: Edinger-Westphal nucleus, muscarinic receptors);
Accommodation,
Eyelid opening (levator palpebrae)
194
Q

Cranial nerve reflexes: Corneal reflex

A

Afferent: V1 ophthalmic (nasociliary branch);
Efferent: VII (temporal branch: orbicularis oculi)

195
Q

Cranial nerve reflexes: Lacrimation

A

Afferent is the V1 (loss of reflex does not preclude emotional tears);
Efferent: VII

196
Q

Cranial nerve reflexes: Jaw Jerk

A

Afferent is V3 (sensory- muscle spindle from masseter);

Efferent is V3 (motor-masseter)

197
Q

Cranial nerve reflexes: Pupillary

A

Afferent is II;

Efferent is III

198
Q

Cranial nerve reflexes: Gag

A

Afferent is IX (ipsilateral);

Efferent is X (bilateral)

199
Q

CN VII innervates what muscles

A

Facial movement;
Orbicularis oculi (eye closing);
Stapedius of ear

200
Q

What muscles doe CN IX innervate

A

Swallowing, Stylopharyngeus (elevates pharynx, larynx)

201
Q

Nucleus Solitaris

A

Visceral Sensory information which is taste, baroreceptors and gut distention;
Sensory=Solitaris
CN VII, IX, and X

202
Q

Nucleus Ambiguus

A

Motor innervation of pharynx, larynx, and upper esophagus (e.g. swallowing, palate elevation);
CN IX, X, XI (cranial portion);
aMbiguus=Motor

203
Q

Dorsal motor nucleus

A
Sends autonomic (parasympathetic) fibers to heart, lungs, and upper GI;
CN X
204
Q

How does this structure exit the Skull: CN I

A

cribiform plate

205
Q

How does this structure exit the Skull: CN II

A

Through sphenoid bone (optic canal)

206
Q

How does this structure exit the Skull: ophthalmic artery

A

Through sphenoid bone (optic canal)

207
Q

How does this structure exit the Skull: Central retinal vein

A

Through sphenoid bone (optic canal)

208
Q

How does this structure exit the Skull: CN III

A

Superior Orbital fissure of the sphenoid bone

209
Q

How does this structure exit the Skull: CN IV

A

Superior Orbital fissure of the sphenoid bone

210
Q

How does this structure exit the Skull: V1

A

Superior Orbital fissure of the sphenoid bone

211
Q

How does this structure exit the Skull: VI

A

Superior Orbital fissure of the sphenoid bone

212
Q

How does this structure exit the Skull: ophthalamic vein

A

Superior Orbital fissure of the sphenoid bone

213
Q

How does this structure exit the Skull: parasympathetic fibers

A

Superior Orbital fissure of the sphenoid bone

214
Q

How does this structure exit the Skull: CN V2

A

Foramen Rotundum in the sphenoid bone

215
Q

How does this structure exit the Skull: CN V3

A

Foramen Ovale in the sphenoid bone

216
Q

How does this structure exit the Skull: Middle Meningeal Artery

A

Foramen spinosum in the sphenoid bone

217
Q

How does this structure exit the Skull: CN VII

A

Internal acoustic meatus

218
Q

How does this structure exit the Skull: CN VIII

A

Internal acoustic meatus

219
Q

How does this structure exit the Skull: CN IX

A

Jugular Foramen

220
Q

How does this structure exit the Skull: CN X

A

Jugular Foramen

221
Q

How does this structure exit the Skull: CN XI

A

Jugular Foramen

222
Q

How does this structure exit the Skull: Jugular Vein

A

Jugular Foramen

223
Q

How does this structure exit the Skull: CN XII

A

Hypoglossal Canal

224
Q

How does this structure exit the Skull: Spinal roots of XI

A

Foramen magnum

225
Q

How does this structure exit the Skull: Vertebral Arteries

A

Foramen Magnum

226
Q

What Passes through this structure: Optic Canal

A

CN II, ophthalamic artery, central retinal vein

227
Q

What Passes through this structure: Superior Orbital Fissure

A

CN III, CN IV, V1, VI, ophthalmic vein, sympathetic fibers

228
Q

What Passes through this structure: Foramen Rotundum

A

CN V2

229
Q

What Passes through this structure: Foramen Ovale

A

CN V3

230
Q

What Passes through this structure: Foramen spinosum

A

Middle Meningeal artery

231
Q

What Passes through this structure: Internal Auditory Meatus

A

CN VII, VIII

232
Q

What Passes through this structure: Jugular Foramen

A

CN IX, X, XI, Jugular Vein

233
Q

What Passes through this structure: Hypoglossal Canal

A

CN XII

234
Q

What Passes through this structure: Foramen Magnum

A

Spinal roots of CN XI, Brain stem, vertebral arteries

235
Q

Cavernous Sinus

A

A collection of venous sinuses on either side of the pituitary;
blood from eye and superficial cortex drains to the cavernous sinus and then into the internal jugular vein

236
Q

Cavernous Sinus: what is it in

A

CN III, IV, V1, V2 and VI and postganglionic sympathetic fibers en route to the orbit all pass through the cavernous sinus;
Cavernous portion of internal carotid artery is also here;
Think of it as the nerves of eye movement plus V1 and V2

237
Q

Cavernous sinus syndrome

A

Due to mass effect, fistula, thrombosis;
ophthalmoplegia and decreased corneal and maxillary sensation with normal visual acuity;
CN VI commonly affected

238
Q

CN V motor lesion

A

Jaw deviates toward side of lesion due to unopposed force from the opposite pterygoid muscle

239
Q

CN X lesion

A

Uvula deviates away from side of lesion;

weak side collapses and uvula points away

240
Q

CN IX lesion

A

Weakness turning head to contralateral side of lesion (SCM);
Shoulder droop on side of lesion (trapezius);
The left SCM contracts to help turn the head to the right

241
Q

CN XII lesion (LMN)

A

Tongue deviates toward side of lesion (“lick your wounds”) due to weakened tongue muscles on the affected side

242
Q

Bones of middle ear

A

Malleus, incus, and stapes

243
Q

Inner ear

A

Snail shaped, fluid filled cochlea;
contains basilar membrane that vibrates secondary to sound waves;
Vibration transduced via specialized hair cells to the auditory nerve signaling to the brainstem;
low frequency is heard at apex near helicotrema (wide, flexible);
High frequency heard best at base of cochlea (thin, rigid)

244
Q

Rinne and Weber test for Conductive hearing loss

A

Rinne test is abnormal (bone > air);

Weber Test localized to the affected side

245
Q

Rinne and Weber test for Sensorineural hearing loss

A

Normal Rinne test (Air > Bone);

Weber test localizes to unaffected ear

246
Q

Noise-induced hearing loss

A

Damage to sterocilliated cells in organ of Corti;
Loss of high frequency hearing 1st;
Sudden extremely loud noises can produce hearing loss die to tympanic membrane rupture

247
Q

Facial Lesions: UMN lesion

A

Lesion of motor cortex or connection between cortex and facial nucleus;
Contralateral paralysis of lower face;
Forehead spared due to bilateral UMN innervation

248
Q

Facial Lesions: LMN lesion

A

Ipsilateral paralysis of upper and lower face

249
Q

Facial Lesions: Facial nerve palsy

A

Complete destruction of the facial nucleus itself or its branchial efferent fibers (facial nerve proper);
Peripheral ipsilateral facial paralysis (drooping smile) with inability to close eye on affected side;
Can occur idiopathically, or with lyme disease, herpes simplex, herpes zoster, sarcoidosis, tumors and diabetes;
Treatment includes corticosteroids

250
Q

Mastication muscles

A

3 muscles Masseter, teMporals, Medial pterygoid;
1 opens the mouth-Lateral Pterygoid;
All innervated by V3;
M’s Munch and Lateral Lowers

251
Q

Hyperopia

A

Eye too short for refractive power of cornea;
Light focused behind the retina;
Farsightedness

252
Q

Myopia

A

Eye too long for refractive power of cornea and lens leading to the light focusing in front of retina;
Nearsightedness

253
Q

Astigmatism

A

Abnormal curvature of cornea resulting in different refractive power at different axes;

254
Q

Presbyopia

A

Decrease in focusing ability during accommodation due to sclerosis and decreased elasticity

255
Q

Uveitis

A

Inflammation of anterior uvea and iris, with hypopyon (sterile pus), accompanied by conjuctival redness;
Often associated with systemic inflammatory disorders (sarcoid, RA, Juvenile idiopathic arthritis, TB, HLA-B27 PAIR disorders)

256
Q

Retinitis

A

Retinal edema and necrosis leading to scar;
often viral (CMV, HSC, HZV);
associated with immunosuppression

257
Q

Central retinal artery occlusion

A

Acute, painless, monocular vision loss;

Retina cloudy with attenuated vessels and cherry-red spot at fovea

258
Q

Retinal vein occlusion

A

Blockage of central or branch retinal vein due to compression from nearby arterial atherosclerosis;
Retinal hemorrhage and edema in affected area

259
Q

Diabetic retinopathy: pathophysiology

A

Non-proliferative: damaged capillaries leak blood so lipids and fluid seep into retina and you see hemorrhages and macular edema (treat with macular laser and better glucose control);
Proliferative is chronic hypoxia results in new blood vessel formation with resultant traction on retina (treat with anti-VEGF injections)

260
Q

Glaucoma

A

Optic disc atrophy with characteristic cupping, usually with increased intraocular pressure and progressive peripheral visual field loss

261
Q

Open angle glaucoma

A

Associated with increased age, African American race, family history;
Painless, more common in U.S.;
Primary- Cause unclear;
Secondary- Blocked trabecular meshwork from WBC (e.g. uveitis), RBCs (vitreous hemorrhage), retinal elements (e.g. retinal detachment

262
Q

Closed/Narrow angle glaucoma

A

Primary- enlargement or forward movement of lens against central iris (pupil margin) leads to obstruction of normal aqueous flow through pupil so fluid builds up behind iris, pushing peripheral iris against cornea and impeding flow through trabecular meshwork;
Secondary- hypoxia from retinal disease (e.g., diabetes, vein occlusion) induces vasoproliferation in iris that contracts angle;

263
Q

Chronic closure of glaucoma

A

often asypmtomatic with damage to optic nerve and peripheral vision

264
Q

Acute angle closure of glaucoma

A

true ophthalmic emergency;
increased IOP pushes iris forward causing angle to close abruptly;
very painful, sudden vision loss, halos around lights, rock hard eye, frontal headache;
do not give epinephrine because of its mydriatic effect

265
Q

Cataract

A

Painless, often bilateral, opacification of lens leading to decreased vision;
Risk factors are increased age, smoking, EtOH, excessive sunlight, prolonged corticosteroid use, classic galactosemia, galactokinase deficiency, diabetes (sorbital), trauma, and infections

266
Q

Papilledema

A

optic disc swelling (usually bilateral) due to increased ICP;
enlarged blind spot and elevated optic disc with blurred margins seen on fundoscopic exam

267
Q

CN IV damage

A

motor to superior oblique;
patient’s eye moves upward, particularly with contralateral gaze and head tilt toward the side of the lesion (problems going down stairs, may present with compensatory head tilt in the opposite direction)

268
Q

Miosis

A

constriction, parasympathetic;
1st neuron: Edinger Westphal nucleus to ciliary ganglion via CN III;
2nd Neuron: short ciliary nerves to pupillary sphincter muscles;

269
Q

Mydriasis

A

Dilation, sympathetic;
1st neuron: hypothalamus to ciliospinal center of Budge (C8-T2);
2nd neuron: exit at T1 to superior cervical ganglion (travels along cervical sympathetic chain near lung apex, subclavian vessels;
3rd neuron: plexus along internal carotid, through cavernous sinus: enters orbit as long ciliary nerve to pupillary dilator muscles

270
Q

Pupillary light reflex

A

Light in either retina travels via CN II to pretectal nucleus in midbrain that activates bilaterally the Edinger-Westphal nuclei;
Pupils contract bilaterally;
So light in one eye causes both eyes to constrict

271
Q

Marcus Gunn Pupil

A

Afferent pupillary defect due to optic nerve damage or severe retinal injury;
decreased bilateral pupillary constriction when light is shone in affected eye relative to unaffected eye;
Tested via swinging light reflex

272
Q

Damage to CN III: what areas are affected first

A

outer layer of CN III is parasympathetic;
Inner layer is Motor;
so vascular disease that cuts off oxygen affects motor, and compression first hurts parasympathetic (think aneurysm, uncal herniation)

273
Q

Retinal detachment

A

separation of neurosensory layer of retina (photoreceptors layer with rods and cones) from outermost pigmented epithelium (normally shields excess light, supports retina) leading to degeneration of photoreceptors leading to vision loss;
May be secondary to retinal breaks, diabetic traction, inflammatory effusions;
Often Preceded by posterior vitreous detachment (flashes and floaters) and eventual monocular loss of vision

274
Q

Age related macular degeneration

A

Degeneration of macula (central area of retina);
causes distortion (metamorphopsia) and eventual loss of central vision;
Dry (nonexudative, 80%)- deposition of yellowish extracellular material in and beneath Bruch membrane and retinal pigment epithelium (drusen) with gradual decrease in vision, give antioxidants and multivitamin;
Wet (exudative, 15%)- rapid loss of central vision due to bleeding secondary to choroidal neovascularization, Treat with anti-VEGF or laser

275
Q

internuclear ophthalmoplegia (INO)

A

MLF is pair of tracts that allow for crosstalk between CN VI and CN III nuclei;
coordinates both eyes to move in same horizontal direction;
Highly myelinated;
Lesions seen in demyelination;
Lesions cause medial rectus on ipsilateral side to not tract, but eyes can converge (medial rectus is working)

276
Q

Alzheimer disease: genetics

A

old folks and increased risk in down syndrome;
Genetics: early onset in APP (Chr 21), Presenilin-1 (Chr 14), presenilin-2 (Chr 1), late onset ApoE4 (Chr 19);
ApoE2 (Chr 19) is protective;

277
Q

Histology of Alzheimer disease

A

Decreased ACh;
Extracellular beta amyloid core;
Amyloid beta synthesized by cleaving amyloid precursor protein (APP on Chr 21);
Neurofibrillary tangles are intracellular hyperphosphorylated tau protein = insoluble cytoskeletal elements, and amount correlates to degree of dementia (worst in hippocampus)’
May see amyloid angiopathy which leads to intracranial hemorrhages (parietal lobe is most common)

278
Q

Frontotemporal dementia

A

Picks disease;
dementia, aphasia, parkinsonian aspects;
change in personality;
Spares parietal lobe and posterior 2/3 of superior temporal gyrus;
Pick bodies are spherical tau protein aggregates;
Frontotemporal atrophy leading to disinhibition, impaired judgement and personality changes

279
Q

Lewy body dementia

A

Initially dementia and visual hallucinatinos followed by parkinsonian features;
Alpha-Synuclein defect;
increased ubiquitin is also present

280
Q

Creutzfeldt-Jakob Disease

A

Rapidly progressive (weeks to months) dementia with myoclonus (“startle myoclonus”);
ataxia;
Spongiform cortex;
Prions (PrPc transform into PrPsc sheet (beta pleated sheets that are resistant to proteases) AKA 14-3-3 protein;
EEG shows recurrent bursts of biphasic and triphasic periodic sharp wave complexes

281
Q

Multiple Sclerosis

A

Autoimmune inflammation and demyelination of CNS (brain and spinal cord);
Patients can present with optic neuritis (sudden loss of vision resulting in Marcus Gunn pupils) internuclear ophthalmoplegia, hemiparesis, hemisensory symptoms, or bladder/bowel incontinence;
Relapsing and remitting course;
mostly women in their 20s and 30s, most white;

282
Q

Classic triad of MS

A

Charcot classic triad of MS;

1) Scanning speech;
2) Intention tremor;
3) Nystagmus

283
Q

Multiple Sclerosis: Findings

A

Increased protein (IgG) in CSF;
oligoclonal bands are diagnostic;
MRI is gold standard;
Periventricular plaques (areas of oligodendrocyte loss and reactive gliosis) with destruction of axons;
Multiple white matter lesions separated in space and time

284
Q

Multiple Sclerosis: Treatment

A

beta-interferon, immunosuppresion, natalizumab;
Symptomatic treatment for neurogenic bladder (catheterization, muscarinic antagonists), spasticity (baclofen, GABA receptor agonist), pain (opioids)

285
Q

Acute inflammatory demyelinating polyradiculopathy

A

most common variant of Guillain-Barre syndrome;
autoimmune condition that destroys Schwann cells leading to inflammation and demyelination of peripheral nerves and motor fibers;
Results in symmetric ascending muscle weakness/paralysis beginning in lower extremities;
Facial paralysis in 50% of cases;
Autonomic function may be severely affected (e.g. cardiac irregularities, HTN, or hypotension);
Almost all patients survive;
the majority recover completely after weeks to months;

286
Q

Acute inflammatory demyelinating polyradiculopathy Findings:

A

increased CSF protein with normal cell count (albuminocytologic dissociation);
increased protein leads to papilledema

287
Q

Acute inflammatory demyelinating polyradiculopathy: associated with what

A

Associated with infections (campylobacter jejuni and CMV) leads to autoimmune attack of peripheral myelin due to molecular mimicry, inoculations, and stress, but no definitive link to pathogens;

288
Q

Acute inflammatory demyelinating polyradiculopathy: treatment

A

Treatments are respiratory support, plasmapheresis, IV immune globulins

289
Q

Progressive multifocal leukoencephalopathy

A

demyelination of CNS due due to destruction of oligodendrocytes;
associated with HC virus;
seen in 2-4% of AIDS patients (reactivation of latent viral infection);
Rapidly progressive, usually fatal;
increased risk associated with natalizumab

290
Q

Acute disseminated (postinfectious) encephalomyelitis

A

Multifocal perivenular inflammation and demyelination after infection (commonly measles or VZV) or certain vaccinations (e.g. rabies, smallpox);
MRI shows inflamed white matter of CNS;
treat with high dose IV corticosteroids

291
Q

Metachromatic leukodystrophy

A

autosomal recessive lysosomal storage disease, most common due to arylsulfatase A deficiency;
buildup of sulfatides leads to impaired production of myelin sheath;
findings are central and peripheral demyelinatino with ataxia, dementia;
no treatment

292
Q

Charcot-Marie-Tooth disease

A

also known as hereditary motor and sensory neuropathy (HMSN);
group of progressive hereditary nerve disorders related to the defective production of proteins involved in the structure and function of peripheral nerves or the myelin sheath;
typically autosomal dominant inheritance pattern and associated with scoliosis and foot deformities (high or flat arches)

293
Q

Krabbe disease

A

autosomal recessive lysosomal storage disease due to deficiency of galactocerebrosidase;
Buildup of galactocerebroside and psychosine destroys myelin sheath;
findings are peripheral neuropathy, developmental delay, optic atrophy, globoid cells

294
Q

Adrenoleukodystrophy

A

X-linked genetic disorder typically affecting males;
Disrupts metabolism of very-long fatty acids leading to excessive buildup in nervous system, adrenal gland, and testes;
progressive disease that can lead to long-term coma/death and adrenal gland crisis

295
Q

Partial (focal) seizures

A

Affect 1 area of the brain;
most commonly originate in medial temporal lobe;
often preceded by seizure aura;
can secondarily generalize;
Types: 1) simple partial (consciousness intact)-motor, sensory, autonomic, psychic 2) complex partial (impaired consciousness)

296
Q

Generalized seizures

A

Diffuse;
Absence (petit mal)- 3Hz, no postictal confusion, blank stare, no muscle tone loss;
Myoclonic-quick, repetitive jerks;
Tonic-clonic (grand mal)-alternating stiffening and movement;
Atonic-“drop” seizures (falls to floor) and mistaken fainting

297
Q

Cluster headaches

A

Unilateral;
last 15 minutes to 3 hrs;
Repetitive brief headaches, excruciating periorbital pain with lacrimation and rhinorrhea, may induce Horner syndrome, more common in males;
Treat with inhaled O2 and sumatriptan

298
Q

Tension headache

A

bilateral and constant;
>30 min (4-6 hour);
Steady pain, no photophobia, or phonophobia, no aura;
treat with analgesics, NSAIDs, acetaminophen, amitriptyline for chronic pain

299
Q

Migraine

A

Unilateral;
lasts 4-72 hrs;
Pulsating pain with nausea, photophobia, or phonophobia, may have aura, due to irritation of CN V, meninges, or blood vessels (release of substance P, CGRP, vasoactive peptides);
Treat active migraine with triptans, NSAIDs, and prophylactic with propranolol, topiramate, Ca channel blockers, amitriptyline

300
Q

Peripheral Vertigo

A

more common;
inner ear etiology (e.g. semicircular canal debris, vestibular nerve infection, Meniere disease);
positional testing leads to delayed horizontal nystagmus

301
Q

Central vertigo

A

Brain stem or cerebellar lesion (e.g. stroke affecting vestibular nuclei or posterior fossa tumor);
Findings with directional change of nystagmus, skew deviation, diplopia, dysmetria;
Positional testing leading to immediate nystagmus in any direction; may change directions;
focal neurological findings

302
Q

Sturge-Weber Syndrome

A

Congenital, non-inherited (somatic), developmental anomaly of neural crest derivatives (mesoderm/ectoderm) due to activating mutation of GNAQ gene;
Affects small (capillary-sized) blood vessels leading to port-wine stain of the face (non-neoplastic “birthmark” in CN V1/V2 distribution);
ipsilateral leptomeningeal angioma leads to seizures/epilepsy;
intellectual disability;
and episcleral hemangioma leading to increased IOP leading to early onset glaucoma;

303
Q

Tuberous Sclerosis:

A
HAMARTOMAS: Hamartomas in CNS and skin;
Angiofibromas;
Mitral regurgitation;
Ash-leaf spots;
cardiac Rhabdomyoma;
Tuberous sclerosis;
autosomal dOminant;
Mental retardation;
renal Angiomyolipoma;
Seizures and Shagreen patches;
increased incidence of subependymal astrocytomas and ungual fibromas
304
Q

Neurofibromatosis type 1 (von Recklinghausen disease)

A

Cafe-au-lait spots, Lisch nodules (pigmented iris hamartomas), neurofibromas in skin, optic gliomas, pheochromocytomas;
mutated NF1 tumor suppressor gene (neurofibromas, a negative regulator of Ras) on chromosome 17;
skin tumors of NF-1 are derived from neural crest cells

305
Q

von-hippel-Lindau disease

A

VHL= chromosome 3;
Cavernous hemangiomas in skin, mucosa, organs;
bilateral renall cell carcinomas;
hemangioblastoma (high vascularity with hyperchromatic nuclei) in retina, brain stem, cerbellum, and pheochromocytomas;
autosomal dominant;
mutated VHL tumor suppressor gene on chromosome 3, which results in constitutive expression of HIF (transcription factor) and activation of angiogenic growth factors

306
Q

Astrocytoma or gliobastoma multiforme

A

Adult tumor;
Common in adult, highly malignant primary brain tumor ~1 year median survival;
found in cerebral hemispheres;
can cross corpus callosum (butterfly glioma);
stain astrocytes for GFAP;
Pseudopalisading pleomorphic tumor cells-border central areas of necrosis and hemorrhage

307
Q

Meningioma

A

Adult tumor;
Most common benign, second most common brain tumor;
most often occurs in convexities of hemispheres (near surface of brain) and parasagittal region;
arises from arachnoid cells, is extra-axial (external to brain parenchyma), and may have a dural attachment (tail);
often asymptomatic;
may present with seizures or focal neurological signs;
resection and/or radiosurgery;
spindle cells concentrically arranged in a whorled pattern;
psammoma bodies (laminated calcifications);
has estrogen receptors and can grow during pregnancy;

308
Q

Hemangiobalstoma

A

adult tumor;
most often cerebellar;
associated with von hippel-lindau syndrome when found with retinal angiomas;
can produce erythropoietin leading to secondary polycythemia;
Closely arranged, thin-walled capillaries with minimal interleaving parenchyma

309
Q

Schwannoma

A

Adult tumor;
usually found at cerebellopontine angle;
schwann cell origin;
s-100 positive;
often localized to CN VIII leading to acoustic schwannoma (aka acoustic neuroma);
resectable or treated with stereotactic radiosurgery;
bilateral acoustic schwannomas found in NF-2;

310
Q

Oligodendroglioma

A
Adult, relatively rare, slow growing;
most often in frontal lobes;
chicken-wire capillary pattern;
oligodendrocytes=fried egg cells (round nuclei with clear cytoplasm);
often calcified in oligodendroglioma;
surgically remove but may return
311
Q

Pituitary adenoma

A

Adult cancer
most commonly prolactinoma;
bitemporal hemianopia due to pressure on optic chiasm;
hyper or hypo pituitarism are sequelae;

312
Q

Pilocytic astrocytoma

A

usually well circumscribed;
Children, most often found in posterior fossa (e.g. cerebellum);
Cystic and solid on gross exam;
may be supratentorial;
Rosenthal fibers-eosinophilic, corkscrew fibers;
GFAP +;
benign, good prognosis

313
Q

Medulloblastoma

A

highly malignant childhood cerbellar tumor;
a form of primitive neuroectodermal tumor;
can compress 4th ventricle, causing hydrocephalus;
can send “drop metastases” to spinal cord;
Homer-Wright rosettes;
solid on gross exam;
small blue cells on histology

314
Q

Ependymoma

A

Childhood Ependymal cell tumors most commonly found in 4th ventricle;
can cause hydrocephalus;
poor prognosis;
characteristic perivascular rosettes;
rod-shaped blepharoplasts (basal ciliary bodies) found near nucleus

315
Q

Craniopharyngioma

A

Benign childhood tumor, may be confused with pituitary adenoma (both can cause bitemporal hemianopia);
most common childhood supratentorial tumor;
derived from remnants of Rathke pouch;
Calcification is common (tooth enamel like)

316
Q

Effect on glaucoma: epinephrine

A

alpha agonist;
decrease aqueous humor synthesis via vasoconstriction;
Side effects are mydriasis, do not use in closed angle glaucoma

317
Q

Effect on glaucoma: Brimonidine

A

Alpha 2 agonist;
decrease aqueous humor synthesis;
side effects are blurry vision, ocular hyperemia, foreign body sensation, ocular allergic reactions, ocular pruritus

318
Q

Effect on glaucoma: timolog, betaxolol, carteolol

A

beta blockers;
decrease aqueous humor synthesis;
side effects are no pupillary or vision changes

319
Q

Effect on glaucoma: acetazolamide

A

Decrease aqueous humor synthesis via inhibition of carbonic anhydrase;
Side effects are no pupillary or vision changes

320
Q

Effect on glaucoma: direct and indirect cholinomimetics

A

direct-pilocarpine, carbachol;
indirect-physostigmine and echothiophate;
increase outflow of aqueous humor via contraction of ciliary muscle and opening of trabecular meshwork;
Use pilocarpine in emergencies-very effective at opening meshwork into canal of Schlemm;
Side effects are miosis and cyclospasm (contraction of ciliary muscles)

321
Q

Effect on glaucoma: Latanoprost (PGF2alpha)

A

Increased outflow of aqueous humor;

Side effect of darkening color of iris (browning)

322
Q

Opioid analgesics: drug names

A

morphine, fentanyl, codeine, loperamide, methadone, meperidine, dextromethorphan, diphenoxylate;

323
Q

Opioid analgesics: mechanism

A

act as agonists at opioid receptors (mu= morphine, delta= enkephalin, kappa= dynorphin) to modulate synaptic transmission- open K+ channels, close Ca2+ channels leading to decrease synaptic transmission;
Inhibit release of ACh, NE, 5-HT, glutamate, substance P

324
Q

Opioid analgesics: Clinical use

A

Pain, cough suppression (dextromethorphan), diarrhea (loperamide and diphenoxylate), acute pulmonary edema, maintenance programs for heroin addicts (methadone)

325
Q

Opioid analgesics: Toxicity

A

Addiction, respiratory depression, constipation, miosis (pinpoint pupils), additive CNS depression with other drugs;
Tolerance does not develop to miosis and constipation;
toxicity treated with naloxone or naltrexone (opioid receptor antagonist)

326
Q

Butorphanol

A

Mechanism: Mu-opioid receptor partial agonist and kappa-opioid receptor agonist, produces analgesia;
Clinical use: severe pain (migraine, labor, etc.), causes less respiratory depression than full opioid agonists;
Toxicity: can cause opioid withdrawal symptoms if patient is also taking full opioid agonist (competition for opioid receptors), overdose not easily reversed with naloxone

327
Q

Tramadol

A

Mechanism: very weak opioid agonist, also inhibits serotonin and NE reuptake (works on multiple neurotransmitters- “tram-it all” in with tramadol);
Used in chronic pain;
Toxicity: similar to opioids, decreases seizure threshold, serotonin syndrome

328
Q

Ethosuxamide

A

Used for generalized absence seizures;
mechanism- blocks thalamic T type Ca2+ channels;
side effects of GI, fatigue, headache, urticaria, steven-johnson, EFGHIJ (ethosuximide causes Fatigue, Gi distress, Headache, Itching, and steven Johnson);
SUX to have Silent Seizures

329
Q

Benzodiazepines

A

Names: diazepam, lorazepam;
used for status epilepticus;
mechanism: increased GABA-a action (increases frequency of Cl- channel opening);
Side effects: sedation, tolerance, dependence, respiratory depression;
also used for eclampsia seizure after MgSO4

330
Q

Phenytoin

A

Used for simple, complex, tonic-clonic, status epilepticus;
increased Na+ channel inactivation;
zero-order kinetics;
Side effects of nystagmus, diplopia, ataxia, sedation, gingival hyperplasia, hirsutism, peripheral neuropathy, megaloblastic anemia, teratogenesis (fetal hydantoin syndrome) SLE-like syndrome, induction of cyp P-450, lymphadenopathy, Steven Johnson, osteopenia

331
Q

Carbamazepine

A

Used for simple, complex, and tonic-clonic;
increased Na+ channel inactivation;
Side effects-Diplopia, ataxia, blood dyscrasias (agranulocytosis, aplastic anemia), liver toxicity, teratogenesis, induction of cyp P450, SIADH, steven johnson;
1st line for trigeminal neuralgia

332
Q

Valproic acid

A

Used for simple, complex, tonic-clonic, and absence seizures;
Increased Na+ channel inactivation, increased GABA concentration by inhibiting GABA transaminase;
Side effects are GI, distress, rare but fatal, hepatotoxicity (measure LFTs), neural tube defects in fetus (spina bifida), tremor, weight gain, contraindicated in pregnancy;
Also used for myoclonic seizures, bipolar disorder

333
Q

Gabapentin

A

Simple, Complex, tonic-clonic seizures;
Primarily inhibits high voltage-activated Ca2+ channels, designed as GABA analog;
side effects sedation and ataxia;
Also used for peripheral neuropathy, postherpetic neuralgia, migraine prophylaxis, bipolar disorder

334
Q

Phenobarbital

A

used for simple, complex, tonic-clonic seizures;

increased GABAa action (increases the duration of opening Cl channel)

335
Q

Topiramate

A

For simple, complex and tonic clonic;
blocks Na+ channels, increased Gaba action;
Side effects are Sedation, mental dulling, kidney stones, weight loss;
Also used for migraine prevention

336
Q

Lamotrigine

A

For simple, complex, tonic-clonic, absence;
blocks voltage-gated Na channels;
Side effects are steven johnson (titrate slowly)

337
Q

Levetiracetam

A

For simple, complex, and tonic clonic;

Mechanism is unknown, may modulate GABA and glutamate release

338
Q

Tiagabine

A

for simple, complex seizures;

increases GABA by inhibiting re-uptake

339
Q

Vigabatrin

A

Simple and complex seizures;

Increase GABA by irreversibly inhibiting GABA transaminase

340
Q

barbiturates

A

Names: phenobarbital, pentobarbital, thiopental, secobarbital;
Mechanism: facilitate GABAa action by increasing duration of Cl- channel opening, thus decrease neuron firing;
Contraindicated in porphyria;
Used for: sedative for anxiety, seizures, insomnia, induction of anesthesia (thiopental);
Toxicity: respiratory and cardiovascular depression (Can be fatal); CNS depression (can be exacerbated by EtOH use), dependence, drug interactions (induces cyp P-450), overdose treatment is supportive (assist respiration and maintain BP)

341
Q

Benzodiazepines: names

A

Diazepam, lorazepam, triazolam, temazepam, oxazepam, midazolam, chlordiazepoxide, alprazolam

342
Q

Benzodiazepines: mechanism

A

Facilitate GABAa action by increased frequency of Cl- channel opening;
decrease REM sleep;
most have long half-lives and active metabolites (exceptions: triazolam, oxazepam, and midazolam are short acting leading to higher addictive potential)

343
Q

Benzodiazepines: Uses

A

Anxiety, spasticity, status epilepticus (lorazepam and diazepam), detoxification (especially alcohol withdrawal-DTs), night terrors, sleepwalking, general anesthetic (amnesia, muscle relaxation), hypnotic (insomnia)

344
Q

Benzodiazepines: toxicity

A

Dependence, additive CNS depression effects with alcohol;
less risk of respiratory depression and coma than with barbiturates;
treat overdose with flumazenil (competitive antagonist at GABA benzodiazepine receptor)

345
Q

Benzo, barbs, and EtOH all bind what

A

bind the GABAa receptor, which is a ligand-gated Cl- channel

346
Q

Nonbenzodiazepine hypnotics: names

A

Zolpidem (ambien), Zaleplon, esZopiclone (ZZZs put you to sleep);

347
Q

Nonbenzodiazepine hypnotics: mechanism

A

act via the BZ1 subtype of the GABA receptor

348
Q

Nonbenzodiazepine hypnotics: Clinical use

A

insomnia

349
Q

Nonbenzodiazepine hypnotics: Toxicity

A

ataxia, headaches, confusion;
short duration because of rapid metabolism by liver enzymes;
unlike older sedative-hypnotics, cause only modest day after psychomotor depression and few amnestic effecs;
decreased dependence risk compared to benzodiazepines

350
Q

Nonbenzodiazepine hypnotics: treat toxicity with

A

Effects reversed by flumazenil

351
Q

Anesthetics-general principles

A

CNS drugs must be lipid soluble (cross BBB) or be actively transported;
Drugs with decreased solubility in blood=rapid induction and recovery times;
drugs with increase solubility= increased potency= 1/MAC;

352
Q

what is the minimal alveolar concentration

A

(of inhaled anesthetic) required to prevent 50% of subjects from moving in response to noxious stimulus (e.g. skin incision)

353
Q

inhaled anesthetics: names

A

halothane, enflurance, isoflurane, sevoflurane, methoxyflurane, nitrous oxide

354
Q

inhaled anesthetics: effects

A

Myocardial depression, respiratory depression, nausea/emesis, increased cerebral blood flow (decrease cerebral metabolic demand)

355
Q

inhaled anesthetics: toxicity

A

Hepatotoxicity (halothane), nephrotoxicity (methoxyflurane), proconvulsant (enflurane), expansion of trapped gas in a body cavity (nitrous oxide);
can cause malignant hyperthermia

356
Q

Malignant hyperthermia

A

rare, life-threatening hereditary condition in which inhaled anesthetics (except nitrous oxide) and succinylcholine induce fever and severe muscle contractions;
treat with dantrolene

357
Q

Barbiturates: intravenous anesthetics

A

Thiopental-high potency, high lipid solubility, rapid entry into brain;
used for induction of anesthesia and short surgical procedures;
effect terminated by rapid redistribution into tissue (i.e. skeletal muscle) and fat;
decreased cerebral blood flow

358
Q

Benzodiazepines: intravenous anesthetics

A

Midazolam most common drug used for endoscopy;
used adjunctively with gaseous anesthetics and narcotics;
may cause severe postoperative respiratory depression, decreased BP, and anterograde amnesia;
treat overdose with flumazenil

359
Q

Arylcyclohexylamines (ketamine)

A

PCP analogs that act as dissociative anesthetics;
block NMDA receptors;
cardiovascular stimulants;
cause disorietnation, hallucinations, and bad dreams;
increase cerebral blood flow;

360
Q

Opioids: intravenous anesthetics

A

Morphine, fentanyl used with other CNS depressants during general anesthesia

361
Q

Propofol: intravenous anesthetics

A

Used for sedation in ICU, rapid anesthesia induction, and short procedures;
less postoperative nausea than thiopental;
potentiates GABAa

362
Q

Local anesthetics: names

A

Esters (procaine, cocaine, tetracaine);

Amides (Lidocaine, mepivacaine, bupivacaine, (amides have 2 I’s))

363
Q

Local anesthetics: mechanism

A

Block Na channels by binding to specific receptors on inner portion of channel;
preferentially bind to activated Na channels, so most effective in rapidly firing neuorns;
Tertiary amine local anesthetics penetrate membrane in uncharged form, then bind to ion channels as charged form

364
Q

Local anesthetics: order of nerves they block

A

small diameter blocked before big;
myelinated fibers blocked before unmyelinated fibers;
overall, size matters more than myelination;
Lose 1)pain then 2) temperature then 3) touch 4) pressure

365
Q

Local anesthetics: Toxicity

A

CNS excitation, severe cardiovascular toxicity (bupivacaine), HTN, hypotension, and arrhythmias (cocaine)

366
Q

Neuromuscular blocking drugs: depolarizing

A

Succinylcholine- strong ACh receptor agonist;
produces sustained depolarization and prevents muscle contraction;
reversal of blockade: Phase 1- (prolonged depolarization)-no antidote. Block potentiated by cholinesterase inhibitors;
Phase 2- (repolarized but blocked, ACh receptors are available, but desensitized)-antidote consists of cholinesterase inhibitors;
Complication include hypercalcemia, hyperkalemia, and malignant hyperthermia

367
Q

Neuromuscular blocking drugs: Nondepolarizing

A

Tubocurarine, atracurium, mivacurium, pancuronium, vecuronium, rocuronium- competitive antagonists-compete with ACh for receptors;
Reversal of blockade-neostigmine (must be given with atropine to prevent muscarinic effects such as bradycardia), edrophonium, and other cholinesterase inhibitors

368
Q

Dantrolene

A

Prevents the release of Calcium from the sarcoplasmic reticulum of skeletal muscle;
Uses: used to treat malignant hyperthermia and neuroleptic malignant syndrome (a toxicity of antipsychotic drugs)

369
Q

Parkinson disease drugs: dopamine agonists

A

Bromocriptine (ergot), pramipexole, ropinirole (non-ergot);

non-ergots are preferred;

370
Q

Parkinson disease drugs: increased dopamine

A

Amantadine (may increase dopamine release);
also used as an antiviral against influenza A and rubella;
toxicity=ataxia;
L-dopa/Carbidopa (converted to dopamine in CNS)

371
Q

Parkinson disease drugs: Prevent dopamine breakdown

A

Selegiline (selective MAO type B inhibitor);

entacapone, tolcapone (COMT inhibitors- prevent L-dopa degradation leading to increased dopamine availability)

372
Q

Parkinson disease drugs: curb excess cholinergic activity

A

Benztropine (antimuscarinic; improves tremor and rigidity but has little effect on bradykinesia);
Park your Benz

373
Q

L-dopa(levodopa)/carbidopa: Mechanism

A

increased level of dopamine in brain;
unlike dopamine, L-dopa can cross BBB and is converted by dope decarboxylase in the CNS to dopamine;
carbidopa, an peripheral decarboxylase inhibitor, is given with L-dopa to increased the bioavailability of L-dopa in the brain and to limit peripheral side effects;

374
Q

L-dopa(levodopa)/carbidopa: Clinical use

A

Parkinson disease

375
Q

L-dopa(levodopa)/carbidopa: toxicity

A

Arrhythmias form increased peripheral formation of catecholamines;
long-term use can lead to dyskinesia following administration (“on/off” phenomenon), akinesia between doses

376
Q

Selegiline

A

Mechanism: selectively inhibits MAO-B, which preferentially metabolized dopamine over NE and 5-HT, thereby increased the availability of dopamine;
Clinic use: adjunctive agent to L-Dopa in treatment of Parkinson disease;
Toxicity: may enhance adverse effects of L-dopa

377
Q

Memantine

A

Alzheimer drug;
Mechanism: NMDA receptor antagonists, helps prevents excitotoxicity (mediated by Ca2+);
Toxicity: dizziness, confusion, hallucinations

378
Q

Donepexil, galantamine, rivastigmine

A

Alzheimer drugs;
Mechanism: AChE inhibitors;
Toxicity: nausea, dizziness, insomnia

379
Q

Neurotransmitter changes in Huntington disease

A

decreased GABA, Decreased ACh, increased dopamine

380
Q

Medications for Huntington disease

A

Tetrabenazine and reserpine- inhibit vesicular monoamine transporter (VMAT), limit dopamine vesicle packaging and release;
Haloperidol- dopamine receptor antagonist

381
Q

Sumatriptan

A

Mechanism: 5-HT(1B/1D) agonist;
inhibits trigeminal nerve activation, prevents vasoactive peptide release, induces vasoconstriction;
half life