Neuro Flashcards
(83 cards)
1
Q
Pancoast tumors and Horner’s syndrome
A
Among other symptoms, Pancoast tumors can lead to Horner’s syndrome due to involvement of the cervical sympathetic ganglia.
2
Q
Neural Tube Defects
- Pathophysiology
- Presentation
- Dx
A
- NTDs occur due to failure of fusion of the neural tube during the 4th week of development. This leaves an opening between the neurotube and the amniotic cavity.
- Can present with encephalocele (herniation), anencephaly (no brain), or the spina bifadas
- Leakage of alpha-fetpoprotein and AchE occurs, allowing for prenatal diagnosis
3
Q
Name the microscopic and macroscopic changes associated with Ischemic Brain Injury, during the following times after injury:
- 12-24 hours
- 24-72 hours
- 3-7 days
- 1-2 weeks
- >2 weeks
A
4
Q
What does the radial nerve do? Damage to it may result in what?
A
- Innervation to the skin of the posterior arm, forearm, and dorsal lateral hand
- Motor innervation to all of the extensors of the upper limb (below the shoulder)
Damage leads to wrist drop
5
Q
What artery is responsible for supplying the occipital lobe?
A
Posterior Cerebral Artery
6
Q
What is Vernet syndrome?
A
It is when you have lesions of the jugular foramen, thus leading to CN Ix, X, and XI dysfunction
7
Q
Meningiomas
- Pathophysiology?
- Who is usually affected?
- Where do these tumors occur?
- Presentation?
A
- Common, slow-growing (benign), intracranial tumors
- Typically adults
- Arise in regions of dural reflection (falx cerenri, tentorium cerebelli, etc.)
- Patients are often asymptomatic but may present w/ HA, seizure or focal neurologic deficits depending on size/ location of tumor
8
Q
Role of the musculocutaneous nerve (2)
A
- Innervates the major forearm flexors and the coracobrachialis
- Provides sensory innervation to the lateral forearm
9
Q
What are the (3) main dopaminergic systems? What are their functions? What diseases are they associated with?
A
10
Q
How can severe chronic rheumatoid arthritis lead to spinal cord injury?
A
It can cause joint destruction with verterbal malalignment (subluxation), particularly at C1. Extension of neck (particularly during ET placement), can worsen the subluxation, leading to acute compression of the spinal cord and/or vertebral arteries
11
Q
Intraventricular Hemorrhage
- Most frequent occurance is in what population?
- Pathology?
- Presentation?
A
- Usually in infants born before 32 weeks gestation or with a low birth weight
- IVH in premies usually originates in germinal matrix, where neurons and glial cells migrate out during brain development
- Clinically silent or present with altered level of conciousness, hypotonia, and decreased movement. Symptoms of catstrophic bleeding are the same as those of increased ICP.
12
Q
What is Kinesin and what does it do?
A
A microtubule-associated, ATP-powered motor protein that facilitates the anterograde transport of neurotranmsitter-containing secretory vesicles down axons to synaptic terminals.
13
Q
IV Benzodiazepines
- Main one
- Indication
- MOA
A
- Lorazepam
- Intitial drug of choice for status epilepticus
- They work by enhancing the effect of GABA at GABA -A receptor, leading to increased chloride influx and suppression of AP firing
14
Q
Why doesn’t Wallerian degeneration occur in the CNS?
A
Due to the persistence of myelin debris, secretion of neuronal inhibitory factors, and development of dense glial scarring.
15
Q
Germinoma
- What type of mass is it?
- Classical manifestations (2) and the Sx associated with each (3)
- Dx
A
- Pineal gland mass
- (1) Obstructive hydrocephalus due to aqueductal stenosis - Sx: papilledema, HA, vomiting (2) Dorsal midbrain (Parinaud) syndrome due to direct compression of the pretectal region of the midbrain- Sx: paralysis of upward gaze, ptosis, pupillary abnormalities
- Dx via MRI
16
Q
“Red ragged” muscle fibers on Gomori trichome are seen in what kinds of disease…?
A
Mitochondrial diseases
The mitochondria accumulate under sarcolemma
17
Q
Diabetic Mononeuropathy
- Usually involves which CN?
- Pathology
- Sx (3)
A
- CN III is most commonly involved
- Caused predominantly by central ischemia
- Sx: ptosis, “down and out” gaze, normal light/accomodation reflexes
18
Q
POMC, a polypeptide precursor, goes through enzymatic cleavage and modification to produce what (3) proteins?
A
- Beta-endorphins (endogenous opioid peptide)
- ACTH
- MSH
19
Q
Length constant
(How is it affected by myelination?)
A
A measure of how far along an axon an electrical impulse can propagate. Myelination increases this constant.
20
Q
Lesch-Nyhan Syndrome
- Inheritance?
- Presentation?
- Pathology?
- The [] of what enzyme increases as a result?
A
- X-linked recessive
- Presentation: self-mutilation, hyperuricemia, dystonia, and choreoathetosis in the first few years of life
- Pathology: HGPRT deficiency (used in purine salvage pathway). Leads to degradation of hypoxanthine bases into uric acid.
- Increased demand for de novo purine synthesis leads to increased PRPP activity
21
Q
Tabes Dorsalis
- Epidemiology?
- Pathogenesis?
- Clinical findings?
A
- Epidemiology: Increased incidence of syphilis in MSM/ HIV-infected patients
- Pathology: Treponema pallidum spirochetes directly damage the dorsal sensory roots
- Clinical findings: sensory ataxia, lancinating pains, neurogenic urinary incontinence, Argyll Robertson pupils
22
Q
Maple Syrup Urine Disease (MSUD)
- Pathology
- Presentation
- Treatment
4.
A
- Path: defect in a-keto dehydrogenase, leading to inability to degrade branched chain amino acids (leucine, isoleucine, valine) beyond deaminated a-keto acid state
- Sx: Dystonia; poor feeding; maple syrup scent urine in first few days of life
- Tx: Dietary restriction of branched-chain AA’s
23
Q
Causes of oral thrush (3 main)
A
- Candida albicans
- Albuterol inhaler
- HIV
24
Q
Vitamin A toxicity
- Acute affects (3)
- Chronic affects (5)
- Teratogenic affects (3)
A
- Acute: N/V, vertigo, blurred vision
- Chronic: alopecia, dry skin, hyperlipidemia, hepatotoxicity/ hepatosplenomegaly, and visual difficulties
- Teratogenic: Microcephaly, cardiac anomalies, fetal death
25
What time interval is the key difference between PTSD and Acute Stress Disorder?
Acute stress disorder
26
What are the main effects of a glossopharyngeal nerve lesion?
1. Loss of **gag reflex**
2. Loss of **general sensation** of the upper pharynx, posterior tongue, tonsils and middle ear cavity
3. Loss of **taste** on posterior third of tongue
27
Which neural structure is most affected by the thiamine deficiency associated with Wernicke encephalopathy?
Mamillary bodies
28
_First generation anti-histamines_
1. Name them
2. In addition to blocking histamine receptors, what other affects?
3. How can the eye be affected?
1. Ex. **Chlorpheniramine, diphenhydramine**
2. Also have antimuscarinic, anti-alpha adrenergic, and anti-serotonergic properties
3. Anticholinergic effects on occular ciliary muscles impair accomdation and cause **blurring of vision for close obects**
29
The anterior cerebral arteries supply which portions of the brain? (2)
What is the affect that occlusion can have?
1. They supply the medial portions of the 2 hemispheres (frontal and parietal)
2. Occlusion can cause contralateral motor and sensory deficits of the lower extremities, behavorial changes, and urinary incontinence
30
1. _Peroxisomes_ are responsible for metabolizing what?
2. What does _Peroxisomal disease_ commonly lead to?
1. Metabolizes very long chain fatty acids or fatty acids with branch points at odd-numbered carbons since they cannot undergo mitochondrial beta-oxidation
2. Can lead to neurologic defects from _improper CNS myelination_
31
Injury to the _lower trunk of the brachial plexus_
1. What mechanism of injury which causes this?
2. Consequence of this injury?
1. Result of **sudden upward jerking** of the arm at the shoulder
2. May causes paralysis of all **intrinsic hand muscles (Klumpke's palsy)** w/ sparing to the extensors, leading to **total claw hand deformity**. Can also see sensory loss and weakness.
32
When providing a nerve block of the brachial plexus between scalene muscles, what must you be weary of?
Transient ipsilateral diaphragmatic paralysis due to involvement of the phrenic nerve roots as they pass through the interscalene sheath.
33
_Serotonin syndrome_
1. How do we get this syndrome?
2. Sx (3)
3. What is the antidote?
4. What is the precursor to serotonin?
1. The result of either serotonin overdose or co-prescription with an MAOI or triptan
2. (1) neuromuscular excitation, (2) autonomic stimulation, (3) altered mental status
3. _Antidote_- **Cyproheptadine** ( a first generation histamine antagonist)
4. **Tryptophan** is the precursor to serotonin
34
Sx of _trapezius_ weakness vs _deltoid_ weakness
_Trapezius_- drooping of shoulder, impaired abduction **above horizontal,** winging of the scapula
_Deltoid_- impaired abduction at angles below the horizontal plane
35
_Diazepam_
1. Indications (4)
2. SEs (1 most common)
3. Contraindications
1. **Indications**: (1) anxiolytic, (2) sedative-hypnotic, (3) anticonvulsant, (4) muscle relaxant
2. **SE**: Sedation
3. **Contraindications**: Don't give to patients on other CNS depressants (ex. chlorpheniramine)
36
_Huntington disease_
1. Describe the genetic/cellular level cause of this disease.
2. How are histones involved?
1. Increased CAG trinucleotide repeats in the gene that codes for the huntingtin protein, leading to gain-of-fxn mutation.
2. Transcriptinal repression (silencing), via histone _**de**acetylation,_ is thought to be one of the main mechanisms in which this mutation causes disease
37
_Migraine_
1. Sx
2. Abortive therapy (1)
3. Prophylactic therapy (3)
1. Unilateral HAs, with pulsating/throbbing quality, associated with photophobia, phonophobia, and nausea
2. **Abortive**: Triptans (serotonin agonists)
3. **Prophylactic**: Beta-blockers, antidepressantts, and anti-convulsants
38
_Amyotrophic Lateral Sclerosis_
1. Sx
2. Gross anatomy
3. Histo/ microscopic
4. Genetics
5. Tx
1. **Sx**: _LMN_- muscle weakness, atrophy, fasiculations; _UMN_- spasticity, hypereflexia, pathologic reflexes
2. **Gross**: (1)Thin anterior roots; (2) mild atrophy of precentral gyrus
3. **Histo/micro**: loss of anterior horn neurons, lateral CSTs, motor nuclei neurons, and denervation atrophy of muscles
4. **Genetics**: mutation of gene for superoxide dismutatse (SOD1) may be implicated
5. **Tx**: _Riluzole_ (decreases glutamate release)
39
_Subthalamic nucleus_
1. What pathology can cause damage to this structure?
2. What is the consequence of this damage?
1. **Lacunar stroke** can cause damage
2. Damage may result in **contralateral hemiballism**, characterized by wild, involuntary, large-amplitude, flinging movements of proximal limbs on one side of the body
40
_Ramelteon_
1. MOA
2. Indications
3. SEs
1. **MOA**: melatonin agonist
2. Initial insomnia treatment that demonstrates _high safety and efficacy_ in **older adults**
3. Very few SEs and no dosage adjustment needed
41
_Subarachnoid Hemorrhage_ (SAH)
1. Presentation
2. Pathology and associated diseases (3)
3. Dx
1. **Sx**: "Worst headache of my life" + fever/nuchal rigidity
2. **Path**: Saccular (berry) aneurysms are most common cause. Associated with Ehlers-Danlos syndrome, ADPKD, and AV malformations
3. **Dx**: Non-contrast CT showing hyperdensity in cisterns/sulci; LP showing gross blood or xanthochromia (yellow discoloration of the CSF)
42
_Lambort-Eaton syndrome_
1. Sx
2. Disease associated with
3. Pathogenesis
4. Tensilin test result
5. Nerve stimulation studies
1. **Sx:** weakness improves during the day and with excercise. Weakness of proximal muscles
2. **Assc**. with pre-existing malignancy
3. **Path**: antibodies against pre-synaptic calcium channels
4. No improvement from tensilon test
5. Incremental response from nerve stim. test
43
_Myasthenia Gravis_
1. Sx
2. Disease associated with
3. Pathogenesis
4. Tensilin test result
5. Nerve stimulation studies
1. **Sx**: Weakenss that is worse at the end of the day/ with exertion; extraocular muscles are affected first (ptosis/diplopia)
2. **Assc. with** risk of _thymoma_
3. **Path**: antibodies against Ach receptors
4. Improvement/ resolution w/ tensilon test
5. Decremental response to nerve stim. test
44
1. _Inhibition of uterine contractons_ is a result of stimulation of which adrenergic receptor?
2. _Pupillary dilation_ is the result of stimulation of which adrenergic receptor?
1. B2 (inhibits uterus)
2. a2 (dilates pupils)
45
_Neurofibromatosis Type 1 (NF-1)_
1. Sx (4)
2. Inheritance
3. What type of cells are the main compent of cutaneous neurofibromas?
1. (1) Cafe-au-lait spots, (2) Neurofibromas (short, sessile or pedunculated lesions), (3) Lisch nodules (pigmentated hamartomas of the iris), (4) pseudoarthritis
2. Autosomal-dominate inheritance
3. Schwann cells are the main component
46
_Ataxia-telangiectasia_
1. Inheritance
2. Path
3. Sx/Presentation (4)
1. Autosomal-recessive
2. Result of a defect in DNA-repair genes, making the genes hypersensitive to ionizing radiation
3. Presents as child w/ (1) cerebellar ataxia, (2) oculocutanoeous telangiectasias, (3) repeasted sinopulmonary infxn, (4) inc. incidence of malignancy
47
_Ariginase_
1. Fxn
2. Sx of Arginase deficiency
3. Tx of Arginase deficiency
1. _Fxn_: urea cycle enzyme that produces urea and ornithine from arginine
2. _Sx_: (1) Progressive spastic diplegia, (2) growth delay, (3) abnormal movements
3. _Tx_: Arginine-free, low protein diet
48
_Wilson Dz_
1. Sx (3)
2. Dx
3. Tx
1. **Sx**: Liver injury (sometimes asymptomatic), psych sx's, Basal ganglia injury (leading to parkinsonism)
2. **Dx**: Kayser-Fleischer rings; labs show increased transaminases (liver injury) and low serum ceruloplasmin
3. **Tx**: D-penicillamine
49
_Wilson Disease_
1. Inheritance
2. Path
1. Autosomal recessive mutation of the ATP7B gene
2. _Path:_ Mutation leads to a decrease in copper incorporation into ceruloplasmin and reduced biliary copper excretion leading to copper accumulation in liver, brain, and eye
50
_Zolpidem_
1. Indication
2. SImilar to what drug? How does it differ?
1. Short-acting hypnotic used for **short-term insomnia**
2. Same MOA as benzos but a much lower risk of tolerance and dependence
51
_Tetrodotoxin_
1. Where does it come from?
2. What effect does it have?
1. Comes from pufferfish
2. Binds to voltage-gated sodium channels in nerve and cardiac tissue, preventing sodium influx and depolarization -- leads to paralysis
52
_Treacher-Collins syndrome_
1. Path?
2. What is the effect?
1. Genetic disorder resulting in abnormal development of the first and second pharyngeal arches
2. _Result_: (1) Craniofacial abnormalities which often compromise airway and feeding; (2) absent or abnormal ossicles leading to profound conductive hearing loss
53
What is responsible for the clinical variability of mitochondrial diseases?
**HETEROPLASMY**
The mixture of (2) types of genetic material
54
Propionyl CoA is derived from which amino acids? (4)
Val, Ile, Met, and Thr
55
After invading the nasopharnyx, how does N. meningitidis gain access to the brain?
Bloodstream followed by choroid plexus
56
Clostridium tetani blocks the release of what?
The inhibitors _Glycine_ and _GABA_
57
What are the cutaneous neurofibromas assc. with NF1, derived from? What is its embryological derivation?
They are comprised mostly of _Schwann cells_, which are embryologically derived from the _neural crest_
58
59
Key AE associated with lamotrigine
SJS (30% of body surface)
60
Capsaicin causes depletion of what neurotransmitter? What does this lead to?
_Substance P_
An intitial burning/stinging sensation, but chronic exposure leads to **reduced pain transmission**
61
Length constant
A measure of how far along an axon an electrical impulse can propagate
This is _increased_ by **myelination**
62
What is the most common location for acoustic schwannomas?
Cerebellopontine angle
63
If a patient with HIV has rin-enhancing lesions, and treated for toxoplasmosis is negative, what dz should you suspect?
What cell typically compose this dz?
Suspect _Primary Central Nervous System Lymphom__a_
It is typically composed of B-lymphocytes, and is associated with EBV.
64
Oligodendrocytes Vs Schwann Cells
_Oligodendrocytes_- CNS myelin (oligarchy means central power)
_Schwann_- Peripheral Myelin
65
_Carbamazepine_
1. Indication
2. MOA
3. Adverse Effects
1. Seizure tx
2. Blockage of _voltage-gated sodium channels_ in neuronal membranes
3. Can cause **bone marrow suppression**
66
Function of the suprachiasmatic nucleus (of the hypothalamus)
Circadian rhythm regulation and pineal gland function
67
Conversion disorder
**Neurological** symptoms that are incompatible with a neurological disease. Often stressed associated.
68
Describe themost important biochemical abnormality in Alzheimer dz
Where is this decline most notable?
A dec. in Ach level due to the **deficiency of choline acetyltransferase**, needed to synthesize Ach.
Most notable in the _basal nucleus of Meynert_ or the _hippocampus_
69
What drugs are/can be given with L-DOPA to reduce their peripheral metabolism?
_Carbidopa_- a DOPA decarboxylase inhibitor
_Entacapone_- a COMT inhibitor
These both increase levadopa bioavailability to the brain
70
Name the (2) classes of dopamine agonists (and examples).
What dz are they most often used for?
1. **Ergot compounds**- Bromocriptine
2. **Nonergot compounds**- Pramipexole, ropinirole
71
What drug is used as abortive therapy during an acute migraine?
What is its MOA?
_Triptans_
They are **serotonin 5-HT1B/5-HT1D agonists**, and thus inhibit the release of vasoactive peptides, promoting vasoconstriction, and blocking pain pathways in the brainstem.
72
What is the affect of occluson of the anterior cerebral artery?
**Disruption of sensory and motor function of the contralateral leg and foot**, while sparing the contralateral arm/face
73
What is the (4) step route that N. meningitidis uses to cause meningitis?
Pharynx --\> blood --\> choroid plexus --\> meninges
74
_Cauda Equina Syndrome_
Presentation?
Specific areas damaged?
Saddle anesthesia and loss of the anocutaneous reflex, assc. with damage to the S2 through S4 nerve roots
75
What is responsible for the clinical variability of mitochondrial dz?
The mixture of two types of genetic material, known as heteroplasmy. In other words, during mitosis there is a random distribution of mitochondria, some containing lots of damaged mitochondria, others containing very few.
76
What are the effects of occlusion of the MCA?
1. Contralateral hemiplegia of the face/ upper limb
2. Relative preservation of the lower limb
3. Aphasia (if occlusion is in dominant hemisphere -- usually left)
77
Ethosuximide MOA
Blocks T-type Ca2+ channels in thalamic neurons
(used to treat absence seizures)
78
_Ataxia Telangiectasia_
1. Classic triad
2. Specific defect
1. Cerebellar ataxia + telangiectasias + inc. risk of sinopulmonary infections
2. Defect in the gene that encodes for the ATM gene, which plays a role in DNA break repair
79
What is the cause of _Myotonic Dystrophy_?
An autosomal dominant disorder, leading to increased number of trinucleotide repeats on the myotonia-protein kinase gene
80
Myotonic dystrophy presentation (5)
Sustained muscle contraction (can't release doorknob) + weakness/atrophy
(often also see cataracts, frontal balding and gonadal atrophy)
81
What cell type composes the wall of the cyst in the years after a stroke?
Astrocytic processes (glial scar)
82
What is the most common cause of bacterial meningitis in adults of all ages?
Strep Pneumo
83
What is the neurological effect of vitamin B12 deficiency?
**Subacute combined degeneration!!!**
_demyelination_ of dorsal columns, lateral CST, and spinocerebellar tracts, leading to: ataxic gait, paresthesia, and impaired position/vibration sense
