Week 6 Flashcards
(144 cards)
1
Q
What is the mechanism of action of benzodiazepines?
A
activate more frequently the GABA-A receptor (GABA agonists) - which functions as a Chloride ion channel
2
Q
What type of epilepsy episode is benzodiazepines used for?
A
status epilepticus(lorazepam, diazepam, midazolam)
3
Q
Most benzodiazepines have long half-lives and active metabolites except…? (remember acronym)
A
ATOM are short acting with higher addictive potential1. alprazolam2. triazolam3. oxazepam4. midazolam
4
Q
What is the common suffixes for benzodiazepines? (2)
A
-pam-lam (theres also chlordiazepoxide)
5
Q
Treat overdose of benzodiazepines with?
A
Flumazenil (competetive agonist at GABA receptor)## Footnote* But can precipitate seizures by causing acute benzodiazepine withdrawal
6
Q
How do barbiturates work against seizures?
A
- MOA: bind to allosteric site on GABA-A receptor → improving the effects of GABA
- The GABA-A receptor is a chloride channel - leads to hyper-polarization which inhibits synaptic transmission
- Barbiturates increase the duration of Chloride ion channel
7
Q
Phenobarbital
1. what type of drug is this
2. what types of seizures is this used for? (3)
A
- Barbiturate
- Focal, general tonic clonic, status epilepticus (for stat. ep. -> use other drugs first and then barbiturate is last choice)
8
Q
Phenobarbital
1. side effects
A
- sedation -> cardio and respiratory depression, CNS depressoin
9
Q
Primidone
1. what type of drug is this?
2. What disorders is this used for?
3. side effects
A
- barbiturate
- used to treat seizures and essential tremor
- sedating effects of barbiturates
10
Q
Valproate
1. what kind of drug is this
2. MOA
3. what seizure types is this used for?
A
- Broad spectrum anticonvulsant
- binds VG Na+ channels to prevent high freq. firing of neurons
- focal, generalized, absence
11
Q
Valproate
1. side effects
VALPPROaTTE
A
VALPPROaTTE:
1. Vomiting
2. Alopecia
3. Liver damage (hepatotoxic)
4. Pancreatitis
5. P-450 inhibition
6. Rash
7. Obesity (weight gain)
8. Tremor
9. Teratogenesis (neural tube defects)
10. Epigastric pain (GI distress)
12
Q
Topiramate
1. what kind of drug is this
2. MOA (2)
3. what seizure types is this used for?
A
- broad spectrum anticonvulsant
- Binds to VG Na+ channel AND binds to GABA-A to potentiate effects of GABA
- focal and generalized tonic clonic
13
Q
Topiramate
1. side effects
A
1.Sedation
2.slow cognition
3.kidney stones
4.skinny (weight loss)
5. sight threatened (glaucoma)
6. speech (wordinding) dificulties
14
Q
Lamotrigine
1. what kind of drug is this
2. MOA
3. what seizure types is this used for? (3)
A
- broad spectrum anticonvulsant
- Binds to VG Na+ channels
- Focal, generalized tonic clonic, absence (not as effective for absence as other meds)
15
Q
Lamotrigine
1. side effects
A
- SJS
- Diplopia
16
Q
Levetiracetam
1. what kind of drug is this
3. what seizure types is this used for?
4. side effects
A
- broad spectrum anticonvulsant
- Focal, generalized tonic clonic, absence
- somnolence
17
Q
Carbamazepine
1. what kind of drug is this
2. MOA
3. what situations is this used for?
A
- narrow spectrum anticonvulsant
- Increases Na+ channel inactivation duration
- partial/focal seizure BUT it is actually first line med for trigeminal neuralgia
18
Q
Carbamazepine
1. side effects
A
- Diplopia
- ataxia
- agranulocytosis
- liver toxicity
- teratogenesis (cleft lip/palate, spina biida)
- induction of cytochrome P-450
- SIADH
- SJS
19
Q
Phenytoin
1. what kind of drug is this
2. MOA
3. what situations is this used for?
A
- narrow spectrum anticonvulsant
- increases duration of Na+ channel inactivation
- given as maintenance therapy after status epilepticus + can be used for partial/focal seizures too
20
Q
Phenytoin
1. side effects
PPHENY TOIN
A
PPHENY TOIN:
1. cytochrome P-450 induction
2. Pseudolymphoma
3. Hirsutism
4. Enlarged gums
5. Nystagmus
6. Yellow-brown skin
7. Teratogenicity -cleft palate
8. Osteopenia
9. Inhibited folate absorption
10. Neuropathy
21
Q
Gabapentin
1. what kind of drug is this
2. MOA
3. what situations is this used for?
A
- narrow spectrum anticonvulsant
- blocks VG Ca2+ channels
- Peripheral neuropathy/pain but also partial/focal seizures
22
Q
Gabapentin
1. side effects
A
- sedation and ataxia
23
Q
Vigabatrin and Tigabine
1. What kind of drug is this
2. MOA
3. what situations is this used for?
A
- narrow spectrum anticonvulsants
- two methods of increasing GABA
- partial seizures
24
Q
Ethosuximide
1. What kind of drug is this
2. MOA
3. what situations is this used for?
A
- anticonvulsant
- Blocks T type Ca2+ channels in the thalamus
- 1st line treatment for absence seizures in children
25
1. What pattern is necessary for epilepsy dx?
1. atleast 2 unprovoked seizures occuring >24 hours apart
26
How do you differentiate post-ictal state vs cardiac syncope?
1. After cardiac syncope you are immediately aware of your surroundings but in post-ictal state pt is confused and lacks alertness
27
Generalized
1. What part of brain is affected?
2. What are the types? (4)
1. entire brain
2. Absence "petit mal", tonic clonic "grand mal", Atonic "drop seizure", and myoclonic
28
Generalized Tonic Clonic "grand mal"
1. presentation
1. Tonic - pt clenches their muscles
2. Clonic - muscles begin jerking
3. Involves muscle groups of arms and legs
4. It is immediate, brutal loss of consciousness
29
Absence "petit mal"
1. Common in what type of patient
2. presentation
1. common in children
2. Child stares off into space and eye rolling may be seen
*this needs to be dx*
30
Atonic "drop seizure"
1. presentation
1. pt drops to ground with flaccid muscles
31
Myoclonic seizure
1. presentation
1. Myoclonic seizures are characterized by a sudden body “jolts” or increases in muscle tone as if the person had been jolted with electricity.
32
Focal (partial) seizures
1. involves what part of brain
2. What are the two types
1. discrete part of brain - various parts
2. Simple partial (discrete part of brain with no alteration of consciousness) ;;; Complex partial (discrete part of brain with altered consciousness)
33
1. What is the most common part of the brain that is affected in focal seizures?
2. what changes are seen in the brain?
1. Temporal lobe (Mesial temporal sclerosis)
2. neuronal loss in hippocampus
34
What is secondary generalized seizures?
1. begins as focal seizures then becomes generalized
35
What sx are seen from a temporal lobe epilepsy disorder?
1. loss of consciousness
2. motor automatisms (chewing, lip smacking, etc)
3. langugae disturbances
36
Juvenile Myoclonic Epilepsy
1. common patient
2. presentation
3. Hallmark sx
1. common in children
2. Can include **absence** (around 5 years old), **myoclonic jerks**: bilateral, predominate in upper limbs and occurs WITHOUT LOC (around 15 years old), and **grand mal seizures** soon after
3. Myoclonic jerks on awakening from sleep
37
Childhood Absence Epilepsy
1. presentation
2. Classic EEG finding
3. First line treatment
1. sudden impairment of consciousness - no change in body/motor tone and lasts few seconds
2. 2.5-5Hz spike wave activity
3. Ethosuximide
38
Childhood absence epilepsy
1. How long do episodes last?
2. When does disorder remit?
1. a few seconds
2. remits by puberty
39
History, clinical exam, blood test, EEG, then MRI brain scan -> an example of evaluation of first time what? (BLANK A)
1. First seizure
40
Nodopathy (type of neuropathy)
1. Any peripheral neuropathy caused by changes restricted to the nodes of Ranvier and paranodal regions → via direct injury
41
Axonal neuropathy
1. lack of effective axonal transport. Disruption to this can cause distal axonal degeneration
2. Most axonal neuropathies start with injury of small fibers followed by arge fibers
42
Diabetes related neuropathies
1. Which nerve fibers are damaged? small or large?
2. Positive sx
3. Negative sx
1. Gradual loss of integrity of both
2. excessive sensation like prickling and tingling
3. numbness, sensory loss w/ severe pain, limitation of activities
43
How is diabetic neuropathy dx?
1. Via a nerve conduction study which can detect large nerve fiber injury only
44
What are some sx of peripheral neuropathy?
1. Altered distal symmetric sensory sx
2. Distal symmetric sensory loss
3. Diminished reflexes
45
What type of neuropathy do toxins like amiodarone, n-hexane, arsenic cause?
1. demyelinating neuropathy
*injury of schwann cells which leads to negative effects on myelin*
46
Guillen bare syndrome
1. presentation
2. sx
3. When do sx end?
1. ascending muscle weakness over days and weaks leading to quadriparesis (starts in legs)
2. Decreased/absent reflexes
3. respiratory failure
4. facial muscle weakness
5. mild sensory deficits
6. dysautonomia
sx resolves over weeks to months
47
Guillen Barre
1. When or why does it occur?
2. pathophysiology
1. often begins after URI or gastroenteritis
2. acute inflammatory demyelination due to schwann cells being destroyed by immune system
48
Chronic inflammatory demylinating polyneuropathy (CIDP)
1. time course
2. Affects proximal or distal limbs? (in what way?)
3. sx
1. over 8 weeks
2. progressive symmetric proximal and distal weakness and sensory deficit
3. distal limb pains, fatigue, autonomic dysfunction, CN dysfunction, decreased/absent reflexes
49
Wernicke Encephalopathy is due to a deficiency in what vitamin?
Thiamine deficiency
50
Wernicke Encephalopathy (part of wernicke korsakoff syndrome)
1. what symptoms present
2. changes to brain
3. Is this an acute or chronic presentation?
1. confusion, paralysis of eye movements with nystagmus, gait ataxia, can progress to coma or death
2. punctate hemorrhages and necross adjacent to third ventricle, aqueduct, and fourth ventricle
3. Acute - neurologic emergency
51
Korsakoff Psychosis (part of wernicke korsakoff syndrome)
1. what symptoms present
2. changes to brain
3. Is this an acute or chronic presentation?
1. amnesia with confabulation
2. Remote hemorrhagic lesions with atrophy, cystic degeneration, and hemosiderin deposition -> especially mamillary bodies and thalamus
3. Chronic
52
Thiamine deficiency is most commonly seen in what type of patient?
alcoholics
53
What changes to CNS can happen with vitamin B12 deficiency
1. degeneration of spinal cord (dorsal and corticospinal tracts) - image shows less dark blue areas in these tracts
54
Chronic alcoholism can cause degeneration in what part of the brain
1. cerebellar vermis - loss of granule and purkinje cells
55
Carbon monoxide toxicity
1. what happens to brain?
1. Bilateral necrosis of globus pallidus
+ other changes similar to global hypoxia
56
Hepatic encephalopathy
1. presentation/sx
2. caused by?
1. alteration in consiousness such as confusion or coma, asterixis, elevated blood ammonia levels cause these sx
2. hepatic disorder
57
Neurulation
1. when does it occur
2. explain the process
1. Begins in the 3rd week
------
2. Notochord induces overlying ectodermal cells to differentiate into a thick plate of pseudostratified columnar neuroepithelial cells/neuroectoderm → this is forming of neural plate (neural induction)
---> Cells of notochord block BMP4 signaling pathway to inhibit the overlying ectoderm cells from becoming skin and instead allow them to become neuroectoderm
58
Formation of the neural tube
1. When does this happen
2. Explain the process?
1. 4th week of gestation
2. neural plate folds and forms neural tube (precursor of the nervous system)
-> Lateral lips of the neural folds give rise to neural crest cells
-> closure of neural tube begins in future cervical region and progresses both cranially and caudally
59
1. What are the primary brain vesicles (3)
2. And what final CNS parts does it form?
1. Prosencephalon (cerebral lobes and lateral ventricles/ventricular system)
2. Mesencephalon (midbrain)
3. Rhombencephalon (hindbrain)
60
1. What are the secondary brain vesicles (5)
2. And what final CNS parts does it form?
1. Telencephalon - cerebral hemishpheres
2. Diencephalon - thalamus, hypothalamus
3. Mesencephalon - midbrain
4. Metencephalon - pons, cerebellum, fourth ventricle
5. Myelencephalon - medulla
61
How does Retinoic Acid (RA) help with patterning in growin fetuses?
1. Help polarize the rostral-caudal axis
62
How does Sonic Hedgehod (Shh) help with patterning in growin fetuses?
1. Polarizes the dorsal ventral axis
(along with BMP)
63
How does Bone morphogenetic protein (BMP) help with patterning in growin fetuses?
1. Helps polarize the dorsal ventral axis
(along with Shh)
64
1. How do neurons know where to go and their target?
1. neurons follow proteins known as chemotaxis molecules (can be chemoattractive or chemorepulsive) - all in effort to migrate neurons short and long distances
65
Spina Bifida
1. pathophysiology
2. What are the types (4)
1. failure of vertebral column to close completely
2. Spina bifida occulta, Meningocele, Myelomeningocele, Rachischisis
66
Spina Bifida Occulta
1. What is it?
1. mildest condition of spina bifida that often goes unseen
2. spinal cord is closed normally but the vertebral did not
67
Meningocele
1. What is it?
1. The meninges herniate through vertebral defect
68
Myelomeningocele
1. What is it?
1. meninges and spinal cord herniate through vertebral defect
69
Rachischisis
1. What is it?
1. When neural fold does not join at the midline and the undifferentiated neuroectoderm remains exposed
2. Causes amniotic fluid and neural tube fluid to combine
70
Anencephaly
1. pathophysiology
2. causes what negative effects on CNS
1. failure of the rostral/cephalic neural port
2. prevents proper development of brain, skull, and scalp
71
Chiari malformations
1. pathophysiology
2. sx in person
1. When part of the skull is abnormally small or misshapen -> brain tissue extends into the spinal canal
2. pain, trouble swallowing
72
Dandy Walker Malformation
1. Abnormalities (3)
2.
1. absence of vermis (usually inferior part)
2. Cystically dilated fourth ventricles that fills the enlarged posterior fossa
73
Holoprosencephaly
1. pathophysiology
2. How does this present on person's appearance
1. failure of prosencephalon to divide into cerebral hemispheres
2. eyes may be too close together, may only have one eye
74
Clinical features of a child with fetal alcohol syndrome?
1. microcephaly
2. Short palbebral fissures
3. thin upper lip
and more
75
Differentiate meningitis, encephalitis, and abscess
1. Meningitis - Inflammation of the leptomeninges (arachnoid and pia)
2. Encephalitis - Inflammation of brian parenchyma
3. Abscess - Collection of pus in the brain parenchyma
76
Explain what a positive Kernig sign is that could indicate meningitis?
Pt supine, thigh flexed, attempt to extend the knee but it causes pain and resistance
77
Explain what a positive Brudzinki's sign is that could indicate meningitis?
1. Supine position, passive neck flexion causes spontaneous flexion at the hips
78
What are the classic signs of meningitis on physical?
1. nuchal rigidity
2. Kernig's sign
3. Brudzinki's signs
79
1. acute presentation
2. elevated ICP
3. high protein
4. low glucose
5. >1000 WBC
6. main cell type is neutrophil
**What type of meningitis is this?**
Bacterial meningitis
80
1. somewhat acute presentation
2. normal/slight elevation ICP
3. slight elevation protein
4. normal glucose
5. mild elevation but often <100 WBC
6. main cell type is Lymphocytes
**What type of meningitis is this?**
1. Viral meningitis
81
1. subacute presentation (few weeks)
2. marked elevated ICP
3. elevated protein
4. low glucose
5. Mild elevation of WBC but still <100 WBC
6. main cell type is Lymphocytes
**What type of meningitis is this?**
1. fungal/TB
82
What overall body symptoms can occur with meningitis?
1. Fever
2. Headahce
3. Photophobia
4. Nuchal rigidity
5. Physical exam findings - Kernig and Brudzinkskis
83
What pathology findings (gross) can be found with meningitis?
1. overall brain
2. ventricles
1. swollen or congested brain with purulent exudate
2. ventricles can be compressed or enlarged, may have prurulent exudate
84
Normal opening pressure of ICP?
1. adult (mm H2O)
1. 80-250 mm H2O
85
What is the normal composition of CSF
1. color?
2. cell types?
3. protein?
4. glucose?
5. volume?
1. clear
2. may have lymphocytes (0-5) but no PMNs
3. 25-45 mg/dl protein
4. >45 mg/dl glucose (or >= 60% of the serum level)
5. 150 mL
86
Pathophysiology of meningitis starting with invasion of subarachnoid space by meningeal pathogens?
1. multiplication of organisms and lysis of organisms → release of bacterial cell wall components
2. production of inflammatory cytokines
87
What is the most common cause of meningitis in neonates?
1. group B strep
2. E. Coli
3. Listeria
88
1. What is the most common cause of meningitis in neonates?
2. what can you tx with
1. group B strep
2. E. Coli
3. Listeria
1. ampicillin + gentamycin
89
1. What is the most common cause of meningitis in infants and young children?
2. What can you tx with
1. H. influenza + those affecting young adults and elderly (s. pneumo, N. meningitids, enteroviruses, etc)
2. Ceftriaxone + vancomycin
90
1. What is the most common cause of meningitis in young adults 6-60?
2. What can you tx with
1. Neisseria meningitidis
2. but also can be ( strep pneumo, enteroviruses, HSV)
1. ceftriaxone + vancomycin
91
1. What is the most common cause of meningitis in elderly 60+?
2. What can you tx with
1. strep pneumo, listeria
2. Ceftriaxone + vanco + ampicillin
92
Tuberculosis (TB meningitis)
1. What pathology is found on brain?
2. what microscopic findings occurs?
1. gelatinous or fibrinous exudate often involving base of the brain
2. Necrotizing granulomas with giant cells;;; mixed inflammatory infiltrates including lymphocytes, plasma cells, macrophages
93
Neurosyphilis
1. Due to what disease?
2. What are the three symptomatic forms of neurosyphilis?
1. tertiary syphilis
2. Meningovascular neurosyphilis;; Paretic neurosyphilis;; Tabes Dorsalis
94
Meningovascular Neurosyphilis
1. what is this?
2. location of brain?
1. Chronic meningitis characterized by numerous plasma cells in CNS. Can be seen with gummas -> plasma rich mass lesions in meninges and paranchyma
2. Often at base of brain
95
Paretic Neurosyphilis
1. what is this?
2. location of brain?
1. progressive cognitive impairment associated with mood alterations that terminate in severe dementia
2. often in frontal lobe
96
Tabes Dorsalis
1. Where is degeneration?
2. How does it present?
1. Degeneration of dorsal root ganglia and posterior columns of spinal cord -> loss of axons and myelin which shows as pallor and atrophy
2. Impaired proprioception, ataxia, weakness, diminished reflexes, loss of pain sensation leading to skin and joint damage
97
1. What is the most common cause of viral meningitis?
2. How do you dx
3. How do you treat?
1. enteroviruses (HSV1, HSV2, arbovirus, HIV, etc)
2. viral PCR
3. supportive care, acyclovir if HSV
98
Viral Infection **encephalitis** -> Caused by HSV1
1. what part of the brain does it infect?
2. What pathology occurs?
3. What type of patient does it typically affect?
1. temporal lobe
2. can cause asymmetric hemorrhage necrosis of temporal and inferior frontal lobes
3. immunocompetent individuals
99
Viral Infection **encephalitis** -> Caused by HSV2
1. what part of the brain does it infect?
2. What disorders can be found alonside this?
3. What type of patient does it typically affect?
1. in any part of the brain
2. 1/3 of patients have clinical findings of meningitis as well as genital herpes
3. neonates
100
Viral Infection **encephalitis** -> Caused by HIV
1. What changes occur?
2. when does it occur?
2. pathology shows
1. Cognitive changes
2. end stage disease can cause encephalitis
3. diffuse myelin damage, neuronal loss, microglial nodules, multinucleated giant cells (HIV proteins cause membranes of HIV infected macrophages to fuse and form these)
101
Viral Infection **encephalitis** -> Caused by CMV
1. What patients is this found in?
2. what sx/presentations can arise?
3. Histology findings
1. HIV and AIDS patients with advanced disease (opportunistic infection)
2. CMV retinitis (retinal edema and necrosis cause floaters and decreased vision); periventricular necrosis; periventricular calcification
3. Owl eye inclusions
102
Viral Infection **encephalitis** -> Caused by JC virus
1. Pathophysiology
2. What type of patient presents with this?
3. sx/presentation
1. severe demyelinating disease due to killing of oligodendrocytes and astrocytes.
2. HIV patients (immunocompromised) - since JC is latent and pops up with lacking immune system
3. slow onset encephalitis (altered mental status, focal neural deficits)
103
Viral Infection **encephalitis** -> Caused by Rabies
1. How does infection get to CNS after bite from rabid animal
2. pathophysiology (what hallmark signs are seen in histology)
3. Sx (7)
1. virus replicates in skeletal muscle then transported via axons to CNS which takes about 10 days
2. widespread neuronal degeneration and inflammation -> can see negri bodies in purkinje cells
3. flu sx, paresthesias around wound site, CNS excitability with slightest touch, foaming at the mouth due to contracture of pharyngeal musc., flaccid paralysis -> can progress to coma and death
104
CNS Fungal Infection -> Cryptococcus Neoformans
1. sx
2. How does it infect
3. What testing or work up is done?
4. appearance on imaging
5. What brain issues does it cause (abscess, encephalitis, meningitis, etc?)
1. indolent sx over weeks (fever, headache); can raise ICP
2. inhaled via soil or pigeon droppings, goes to lungs, then blood stream, and finally arrive at meninges (usually in immunocompetent pt)
3. CT or MRI before you do a spinal tap
4. soap bubble appearance in basal ganglia
5. CHRONIC meningitis
105
CNS Fungal Infection -> Aspergillus
1. Type of patient it infects?
2. Tendency to invade what?
3. what do the organisms look like under microscope?
1. immunocompromised pts
2. Blood vessels -> cause thrombosis and cerebral infarctions
3. hyphae branching at acute angles
106
CNS Fungal Infection -> Mucormycosis
1. Type of patient it infects?
2. Tendency to invade what?
3. what do the organisms look like under microscope?
1. diabetics
2. angioinvasive - can do direct nasal infection to orbit and brain
3. broad hypahe, nonseptate, branch at 90 degrees
107
CNS Parasitic Infection -> Toxoplasmosis
1. Type of patient it infects?
2. What CNS damage does it cause: abscess, encephalitis, meningitis?
3. what does this look like in imaging?
1. HIV patients - opportunistic
2. encephalitis
3. multiple ring enhancing lesions - can be throughout brain
108
CNS Parasitic Infection -> Amoebiasis
1. What two organisms can cause this infection? (2)
2. what type of patient most often affected?
3. pathophysiology
1. Naegleria fowler (found in fresh water) + Acanthamoeba (in immunosuppressed patients)
2. immunosupppressed
3. Naegleria fowleri -> infects nasal cavity and spreads to CNS through cribiform plate
109
CNS Parasitic Infection -> Neurocysticercosis
1. caused by what organism
2. What sx does it cause
3. What changes appear in the brain
1. taenia solium
2. seizures - possibly years after exposure
3. What looks like holes in brain
110
Why is elevated ICP worrisome and leads you to get MRI first?
Worried youre going to herniate the patient - if you lower pressure at bottom you can cause herniatiation
111
# First Pharyngeal Arch
1. Derives what bones (4)
2. Derives what muscles (5)
1. maxillary process, mandibular process, malleus and incus
2. Muscles of mastication, anterior digastric, mylohyoid, tensory tympani, anterior 2/3 of the tongue
112
# First Pharyngeal Arch
1. Derives what nerve
2. Derives what artery
1. Trigeminal nerve (V2 and V3)
2. Portion of maxillary artery
113
# Second Pharyngeal Arch
1. Derives what bones (1)
2. Derives what muscles (5)
1. Reichert's Cartilage
2. Stapedius, auricular muscles, stylohyoid, posterior digastric, muscles of facial expression
114
# Second Pharyngeal Arch
1. Derives what nerve
2. Derives what artery
1. Facial
2. Stapedial artery (involutes) and hyoid artery (becomes small branch of internal carotid)
115
# Third pharyngeal arch
1. Derives what bone?
2. Derives what muscle
3. Derives what nerve?
4. Derives what artery? (2)
1. rest of hyoid bone
2. stylopharyngeus
3. CN IX
4. common carotid and proximal internal carotid
116
# 4th and 6th Pharyngeal Arches
1. Derives what nerve
2. Derives what cartilage
3. Derives what muscle
4. Derives what artery (multiple)
1. vagus nerve
2. larynx cartilage
3. laryngeal muscles
4. 4th -> aortic arch and proximal part of subclavian artery + 6th -> pulmonary arch (left and right proximal pulmonary artery + ductus arteriosus)
117
Pharyngeal arches are composed of what types of cell layers? (endoderm, mesoderm, ectoderm)
1. Endoderm and ectoderm
2. except 1st arch which is ectoderm on both sides
118
First pharyngeal POUCH
1. What does it create? (3)
1. many portions of inner ear like eustachian tube
2. middle ear cavity
3. some components of tympanic membrane
119
Second pharyngeal POUCH
1. What does it create? (1)
1. lining of palatine tonsils
120
Third pharyngeal POUCH
1. What does it create? (2)
1. thymus gland
2. left and right inferior parathyroid glands
121
Fourth pharyngeal POUCH
1. What does it create?
1. superior parathyroid glands
2. Ultimobranchial body - incorporates into the thyroid gland and corms C-cells (which release calcitonin)
122
What comes from the foramen cecum on the tongue?
1. The thyroid gland originally came from here and moved inferiorly through the thryoglossal duct
123
1. What to things have to bind to make the upper lip?
2. What happens if it doesnt do this
1. intermaxillary segment (what makes philthrum and middle of nose)
2. maxillary prominencce
-> It can lead to cleft lip
124
What fusion makes the palate form?
Fusion of the maxillary swellings
125
Treacher Collins Syndrome
1. inheritence pattern
2. abnormalities in what arches?
3. leads to what pathology? (3)
1. autosomal dominant - mutation of TCOF1
2. 1st and 2nd arch syndrome
3. underdeveloped facial bones (small mandible, jaw, absent ears, tied tongue) ;; difficulty breathing;; bilateral conductive hearing loss (3)
126
Robbins Sequence
1. inheritence pattern
2. abnormalities in what arches?
3. leads to what pathology?
1. sporadic
2. hypoplasia of 1st arch
3. small mandible (micrognathia) or cleft palate
127
DiGeorge Syndrome
1. inheritence pattern
2. abnormalities in what pouch?
3. leads to what pathology? (3)
1. 22q11 chromosomal deletion
2. 3rd/4th pharyngeal pouch fails to form
3. abnormal thymus and parathyroid function (triad: loss of thymus, loss of parathyroid function, and congenital heart defects)
128
Multiple Sclerosis
1. type of patient
2. pattern of symptom presentation
1. white woman in 20s and 30s
2. relapsing, remitting course
129
Multiple sclerosis
typical sx
1. Optic neuritis (pain and vision loss)
2. MLF syndrome (one eye cannot move medially on lateral gaze)
3. bladder dysfunction
4. Ataxia, motor weakness, parasthesias
130
Multiple Sclerosis
1. Pathophysiology
2. Explain MS plaques
1. autoimmune demyelination of CNS
2. T cells react to myelin antigens - recruit macrophages (type IV hypersensitivity reaction)
-MS plaques -> are typically found in white matter around lateral ventricles but can occur anywhere. These are areas where there myelin is lost - typically myelin made by oligodendrocytes
131
Mutliple Sclerosis
1. What are some alleles that increase risk?
2. What other risk factors?
1. HLA-DRB1
2. environmental factors (viral infections, sun exposure, UV exposure), smoking, etc
132
What is the difference between acute, chronic, shadow MS plaques in multiple sclerosis
1. Acute - actively demyelinating
2. Chronic - "burned out" lesions lack myelin
3. Shadow - some demyelination followed by some re-myelination
133
1. What is the gold standard dx tool for multiple sclerosis
2. What does it show?
1. MRI
2. Plaques that seem to go away and come back in different places with serial imaging (remitting aspect of diseae)
134
What does CSF of MS patients show?
1. high protein
2. Oligoclonal bands (bands of protein)
135
Neuromyelitis Optica
1. Pathophysiology
2. Symptoms (6)
1. More destructive of axons than MS. Via autoantibodies (AQP4-IgG antibody)
2. acute attacks of optic neuritis [severe visual loss and blindness], limb weakness, paraparesis, sensory loss, bladder dysfunction, Brainstem involvement -> can lead to respiratory failure
136
Acute Disseminated Encephalomyelitis
1. pathophysiology
2. when does it occur
3. Histology
4. severe dx shows what sx
1. monophasic immune mediated demyelination
2. 1-2 weeks after vira infection or immunization
3. perivenous lymphocytic and macrophage infiltrate + perivenous demyelination
4. petechiae and edema
137
Osmotic Demyelination Syndrome
1. pathophysiology
2. when does it occur
1. Associated with rapid correction of hyponatremia -> leads to destruction of myelin at base of pons
2. when medically treated (above)
138
Metachromic Leukodystrophy
1. What are the three forms? + include sx at these stages
1. late infantile (6 months to 2 years) - failure to reach milestones
2. juvenile (3-16 yrs) - ataxia and dementia
3. adult - ataxia and dementia
139
Metachromic Leukodystrophy
1. What is it
2. inheritence pattern
3. what enzyme is missing
1. Lysosomal storage disorder (lack of enzyme) that causes lipids (sulfatides) to build up in cells, particularly in the brain, spinal cord and peripheral nerves. This buildup causes impaired production of myelin.
2. autosomal recessive
3. Arylsulfatase A deficiency
140
Krabbe Disease
1. What is it
2. inheritence pattern
3. what enzyme is missing
1. lysosomal storage disease that lacks enzyme to break down galactocerbroside. This galactocerbroside buildup destroys myelin sheath
2. autosomal recessive
3. galactocerebrosidase
141
Krabbe disease
1. Typical age of onset
2. sx
3. histology
1. <6 months of age
2. progressive motor and sensory problems (irritable, developmental delay, limb spasticity, hypotonia, absent reflexes, microcephaly)
3. Globoid cells
142
Adrenoleukodystrophy
1. inheritence pattern
2. pathophysiology
1. X linked recessive
2. Peroxisomal defect - inability to degrade very long chain fatty acids -> leads to damage to myelin sheath
143
What is Lissencephaly?
a rare, gene-linked brain malformation characterized by the absence of normal convolutions (folds) in the cerebral cortex and an abnormally small head (microcephaly)
144
What failed to fuse in a unilateral cleft lip (not involving alveolar margin or palate)?
1. maxillary swelling and medial nasal swelling
