Neuro Flashcards
How does Bell’s palsy affect hearing?
CN VII palsy - affecst entire ipsilateral half of the face
-Hyperacusis - paralysis of the stapedius muscle
What is caused by occlusion of the Basilar Artery?
“Locked in syndrome”
- Preserved consciousness
- Babinski signs
- vertical eye movment
- blinking
- quadriplegia
- loss of voluntary facial, mouth, and tongue movements
What is a Marcus Gunn pupil
afferent pupil defect - optic N/retinal damage
tested with swinging flashlight test
when light swings to affected eye: pupils constrict less than normal
What is the Dx and abnormal protein:
Young boy w progressively worsening “uncoordinated” arm and leg movement slurred speech - Staggering gait, dysarthria
pes cavus
hammer toes
Diabetes Mellitus
Hypertrophic cardiomyopathy
presents in childhood with Kyphoscoliosis
Friedreich ataxia - chromosome 9 (encodes frataxin)
Friedreich is Fratastic (Frataxin): hes your favorite frat brother, always staggering and falling but has a sweet (DM), big heart (hypertrophic cardiomyopathy)
Ataxic (GAAit)
What is the genetic etiology of friedreich ataxia?
Autosomal recessive trinucleotide repeat (GAA) on chromosome 9
Damage to a nerve running through the middle ear will cause salivation impairment to which glands?
Chorda Tympani
Submandibular and sublingual glands
What is a potential adverse effect of vincristine?
Peripheral neuropathy, areflexia, constipation
neuronal axons rely on axonal transport using microtubules
How is Serotonin syndrome distinguished from NMS?
How do their treatments differ?
Serotonin syndrome has hyperreflexia/clonus
SS - Cyproheptadine
NMS - Bromocryptine, Dantrolene
Which Nerve innervates the posterior part of the external auditory canal?
what can happen when this nerve is stimulated?
Auricular branch of VAGUS
stimulation - vasovagal response
What is the embryo origin of:
- Microglia
- PNS
- Schwann cells
- Ectoderm
- Neuroectoderm
- Neuroectoderm
How does a Pilocytic Astrocytoma appear on MRI?
Mass with both solid and cystic components
What are lumbar puncture findings of Subarachnoid Hemorrhage?
Xanthochromia - yellow coloration of CSF b/c of blood (blood is lysed and bilirubin causes color)
Where is Acetylcholine synthesized?
Basal nucleus of Meynert
Where is Dopamine synthesized?
Ventral tegmentum, SNpc
Where is GABA synthesized?
Nucleus accumbens
Where is Norepinephrine synthesized?
Locus ceruleus
Where is Serotonin synthesized?
Raphe nucleus
What are the Neurotransmitter changes in Anxiety?
Increased: NE
Decreased: GABA, Serotonin
What is the neurotransmitter change in Alzheimer disease?
Decreased ACh
increased Glutamate
What is the Neurotransmitter change in Huntington
decreased Acetylcholine
increased Dopamine
decreased GABA
Identify the diease:
Increased Acetylcholine
Decreased Dopamine
Increased Serotonin
Parkinson
What are amniocentesis findings in Neural Tube defects?
increased Alphafetoprotein
increased Acetylcholinesterase
Why is pralidoxime also administered with atropine in organophosphate poisoning?
Atropine only works on muscarinic receptors not nicotinic
pralidoxime is needed to reverse the fx on both types of receptors
What is the classic histopathologic finding of HIV-associated dementia?
Microglial nodules - Microglia/macrophages form multinucleated giant cells around areas of necrosis
identify: 3 month old: irritable, frequent vomiting hydrocephalus intracranial calcifications chorioretinitis
Congenital toxoplasmosis infection
Which nerves pass through the cavernous sinus?
CN III
CN IV
CN V1, V2
CN VI
Which TB drug can cause Sensory Ataxia, decreased pain sensation in distal extremeties?
Why?
What can prevent this?
Isoniazid
-chemically similar to Pyridoxine (B6) so it competes in the production of neurotransmitters (like GABA)
supplement with Pyridoxine
Which thalamic nucleus is involved with:
Pain, temperature, pressure, touch, vibration, proprioception?
Ventral Posterolateral nucleus (VPL)
Which thalamic nucleus is involved with:
Face sensation, taste
Ventral Posteromedial nucleus (VPM)
Which thalamic nucleus is involved with Vision?
Lateral geniculate nucles
Which thalamic nucleus is involved with Hearing?
Medial geniculate Nucleus
Which thalamic nucleus is involved with motor function?
Ventral Lateral Nucleus
How the following dopaminergic pathway be altered and what are the Sx:
Mesocortical
decreased activity - negative symptoms (flat affect, limited speech)
How the following dopaminergic pathway be altered and what are the Sx:
Mesolimbic
Increased activity = positive symptoms (delusions, hallucinations)
Primary therapeutic target of antipsychotic drugs (schizophrenia)
How the following dopaminergic pathway be altered and what are the Sx:
Nigrostriatal
decreased activity = extrapyramidal symptoms (dystonia, akathisia, parkinsonism, tardive
what happens in
1. lateral lesions
2. medial lesions
of the cerebellum
- affect voluntary movement of extremeties, propensity to fall toward injured (ipsilateral) side
- involvement of midline structures (vermis, fastigial nuclei, flocculonodular lobe) =
- Truncal Ataxia (Wide-based cerebellar gait), Nystagmus, head tilting. Generally result in bilatera motor deficits affecting axial and proximal limb musculature
Where is the the lesion in Hemiballismus (sudden flailing of 1 arm +/- ipsilateral leg)
Contralateral subthalamic nucleus (ie lacunar stroke)
What is the inheritance pattern of NF1?
Autosomal dominant, single gene disorder on chromosome 17
Identify dz and first line treatment:
child develops generalized tonic-clonic convulsions without fully regaining consciousness between episodes
Status epilepticus
tx: IV benzodiazepine (eg lorazepam)
- enhance fx of GABA at receptor increasing calcium influx in post synaptic neuron
What embryonic layer is the anterior pituitary derived from?
Rathke pouch (surface ectoderm)
What symptoms occur with damage to arcuate fasciculus?
Conduction
intact speech + comprehension
cant repeat
What brain lesion syndrome is associated with HSV-1 encephalitis?
Kluver-Bucy: bilateral Amygdala lesion
-disinhibited behavior (hyperphagia, hypersexuality, hyperorality)
What is the most common type of brain herniation (brain tissue movement under falx cerebri) - what is the most common cause?
Cingulate herniation
-usually caused by subdural hematoma
What are Sx of a Middle Cerebral artery Stroke?
- Temporal Lobe - Wernickes - INFERIOR division of MCA
- Frontal lobe - Broca - SUPERIOR division of MCA
Contralateral paralysis and sensory loss
- face and upper limb***
Dominant hemisphere (usually left) = APHASIA Nondominant hemisphere = Hemineglect
What are Sx of a Anterior cerebral artery stroke?
Contralateral paralysis and sensory loss
-Lower limb***
What are Sx of a lenticulo-striate artery stroke?
Contralateral paralysis/sensory loss
-face and body***
absence of cortical signs (neglect, aphasia, visual field loss)
What areas are supplied by the anterior spinal artery? What are sx of a stroke in the ASA?
Lateral corticospinal tract
Medial lemniscus
Caudal medulla - hypoglossal nerve
“MEDIAL MEDULLARY SYNDROME”
Contralateral:
1. paralysis - upper + lower limbs
2. decreased proprioception
Ipsilateral:
1. Hypoglossal dysfunction (tongue deviates ipsilaterally
What areas are supplied by the Posterior inferior cerebellar artery? What are sx of a stroke in the PICA?
Lateral Medulla - vestibular nuclei, lateral spinothalamic tract, spinal trigem nucleus, nucleus ambiguus, sympathetic fibers, inferior cerebellar peduncle
“LATERAL MEDULLARY (WALLENBERG) SYNDROME”
—-Nucleus Ambiguus fx are specific for PICA
Vomiting, Vertigo, Nystagmus
Decreased pain/temperature: ipsilateral face, contralateral body
DYSPHAGIA, HOARSENESS
ipsilateral Horner Syndrome, ataxia, dysmetria
What areas are supplied by the Anterior Inferior Cerebellar Artery? What are Sx of a stroke in the AICA?
- Lateral Pons - CN nuclei (vestibular nuclei, facial nucleus, spinothalamic tract, corticospinal tract, sympathetic fibers
- Middle, Inferior Cerebellar Peduncles
“LATERAL PONTINE SYNDROME”
—-Facial Nucleus fx are specific to AICA
Vomiting, vertigo, nystagmus
PARALYSIS OF FACE, decreased lacrimation, decreased taste from anterior 2/3 of tongue
Ipsilateral decreased pain/temp of face,
Contralateral decrease pain/temp of body
Ataxia, dysmetria
What ares are supplied by the Posterior cerebral artery? What are Sx of a stroke in the PCA?
Occipital cortex, visual cortex
Contralateral hemianopia with macular sparing
An aneurysm (compression causing) in which artery can cause ipsilateral CN III palsy
Posterior Communicating Artery
Homozygosity for Apolipoprotein E-4 allele increases the risk for what disease?
Late onset familial Alzheimers
Early onset Alzheimers is related to which mutations
APP - Chromosome 21
Presenilin 1 - chromosome 14
Presenilin 2 - chromosome 1
The release of which 2 neurotransmitters are impaired in C. tetani infection?
glycine
GABA
Identify:
Pt with smoking history
upper limb pain/weakness
ipsilateral ptosis, miosis
Pancoast tumor (non-small cell lung cancer)
Pt has trouble walking down stairs because he see double images
no trouble walking up the stairs
trouble reading
Trochlear Nerve Palsy (CN IV)
-causes hypertropia, extorsion
patient compensates by tucking in chin and tilting head away from affected eye
Little kid gets smashed in the right eye by a baseball
CT: orbital floor fracture
What other neuro deficits will probably be present?
Reduced sensation over right lip
The Urinary incontinence of normal pressure hydrocephalus is caused by what?
Stretching of descending cortical fibers by enlarged ventricular system
identify dz and underlying cause:
progressive sensory ataxia (impaired proprioception, coordination)
charcot joint, shooting pain, argyll robertson pupils
absent DTR’s
+ Romberg
Tabes dorsalis - tertiary syphilis
identify name of sx constellation + associated dz:
bilateral loss of pain/temperature sensation in cape-like distribution
Syringomyelia - syrinx damages anterior white commissure of spinothalamic tract
seen in Chiari I malformation
Ataxic gait, paresthesia, impaired position/vibration sense
demyelination of Spinocerebellar tracts, lateral Corticospinal tracts, Dorsal columns
Vitamin B12 deficiency
What is the rule of 4s in identifying the location of Cranial nerves and the location of CN nuclei?
4CN are above pons (I,II,III,IV)
4CN are in pons (V, VI, VII, VIII)
4CN are in medulla (IX, X, XI, XII)
4CN nuclei are medial (III, IV, VI, XII) “factors of 12 except 1 and 2)
inability to move both eyes vertically
Parinaud syndrome - paralysis of conjugate vertical gaze
–lesion in superior colliculi
what passes through the internal acoustic meatus?
CN VII
CN VIII
labyrinthine artery
What are the associated cranial nerves and function for the following vagal nuclei?
- Nucleus Solitarius
- Nucleus Ambiguus
- Dorsal Motor Nucleus
- VII, IX, X - visceral sensory
- IX, X, XI - motor innervation of pharynx, laryns, upper esophagus (swallowing, palate elevation)
- X - autonomic fibers to heart, lungs, upper GI
What trinucleotide repeat is found in fragile X syndrome?
CGG
identify dz and location of cause: acute onset of agraphia acalculia finger agnosia Left-right disorientation
Gerstmann syndrome
stroke of MCA affecting angular gyrus of DOMINANT Parietal Lobe
What part of the spinal cord does neuro-syphilis damage?
dorsal columns - tabes dorsalis
loss of proprioception, vibration sense, ataxia, Argyll Robertson pupils
What is syringomyelia?
central cystic dilation in the cervical spine - damages anterior white commissure and anterior horns
Identify:
Variable Ophthalmoplegia, decreased corneal sensation, Horner syndrome, occasional decreased maxillary sensation
Cavernous sinus syndrome
CN VI - most susceptible to injury
what general medication classes target Aqueous humor production?
Aq humor production decreases by:
B-blockers
a2-agonists
Carbonic anhydrase inhibitors
Pt with eccentric dietary habits: Papilledema dry skin hepatosplenomegaly alopecia
Vitamin A overuse (pseudotumor cerebri, skin changes, hepatosplenomegaly)
What is the usually the origin of intraventricular hemorrhage in preterm infants?
Germinal matrix
Which drug is preferred in pts with a combination of Absence and Tonic-clonic seizures
Valproic acid
What is the neurotransmitter irregularity in narcolepsy?
hypocretin-1 (orexin-A)
hypocretin-2 (orexin-B)
What is the mechanism of action of Pramipexole when used in Parkinson’s therapy?
Directly stimulates dopamine receptors
also, ropinirole, bromocriptine
What is the first line therapy for acute Status Epilepticus?
Benzodiazepines
What is the first line therapies for generalized Tonic-Clonic seizures?
Phenytoin, Valproic acid
What is the first line therapy for simple and complex partial seizures?
Carbamazepine
What is the first line prophylaxis for status epilepticus?
Phenytoin
What is the mechanism of action of Entacapone, Tolcapone when used in conjunction with levadopa/carbidopa in Parkinsons therapy?
decreasing peripheral levadopa degradation
COMT inhibitor
What is the relationship between blood solubility of a anesthetic and its induction time?
increase in blood solubility = increase in induction
decreased blood solubility = rapid induction and recovery time
What is the relationship between lipid solubility of a anesthetic and its potency?
increase lipid solubility = increased potency = 1/MAC
What vitamin deficiency can mimic Friedrich ataxia?
what cases can this appear in?
Vitamin E deficiency, also includes loss of DTR’s
occurs in fat malabsorption, abetalipoproteinemia
4 year old boy presents with progressive worsening headaches
nonbloody, nonbilious emesis
intermittent blurry vision when looking up when brushing teeth
bilateral papilledema, inability to gaze upwards, bilateral lid retraction
Where is brain lesion?
Pineal gland: obstructive hydrocephalus Dorsal Midbrain (Parinaud) syndrome
Ascending muscle weakness associated with history of upper respiratory or gastrointestinal infection
identify dz and associated bacteria?
Guillain-Barre (endoneural inflammatory infiltration)
strongly a/w Campylobacter jejuni
What a finding of a transtentorial (ie uncal) herniation?
first sign = fixed, dilated pupil on the side of the lesion
ipsilateral paralysis of oculomotor muscles
A lesion to the Medial Longitudinal Fasciculus in what location will cause Internuclear Ophthalmoplegia?
Ipsilateral Dorsal Pons
Where is a lesion located in a Right nasal hemianopia? what artery is involved?
Right perichiasmal lesion - Internal carotid artery
Which atypical antipsychotic can cause agranulocytosis
Clozapine (absent neutrophils, eosinophils)
What are EEG findings of Absence Seizures?
what is the tx for history fo absence seizures? (2)
3 Hz spike and wave discharges
Ethosuximide, Valproic Acid
What is the neurotransmitter that is affected in narcolepsy?
Orexin
What can occur from rapid correction of hyponatremia?
Central pontine myelinolysis - gait ataxia, dysarthria, positive babinskis
A pt had a oligodendroglioma removed from his frontal lobe. what is most likely to occupy space previously filled by the tumor?
Astrocytes - damaged cells in the CNS are replaced by astrocytes = provide structural support to central neurons
4 year old presents with increasing lethargy, HA, N/V. Brain CT - mass lesion in roof of fourth ventricle.
Histology: cell with peripherally located nuclei that form a halo around a eosinophilic lumen. Presence of rod-shaped intracytoplasmic eosinophilic inclusions near the cell nuclei
-Identify dz?
Ependymoma - arise from ependymal lining of the ventricles (most commonly in roof of fourth ventricle)
Sx: increase intracranial pressure
Histology:
–perivascular pseudorosettes,
–Blepharoplasts - rod shaped intracytoplasmic eosinophilic inclusions
CNS cell that does not stain readily by Nissl Staining. have spindle process emanating from central cell body with irregularly shaped nucleus and relatively little cytoplasm
identify cell type and embryonic derivative
Microglia - Mesoderm
During sleep the EEG shows sleep spindles and K-waves. which stage of sleep is this?
Non-REM Stage 2 sleep
What are neurotransmitter changes during REM sleep?
rise in acetylcholine
decrease in norepinephrine
54 year old male presents with progressive myopia over the course of the year. Exam shows increased cup-to-disk ratio (optic disk cupping)
- what is dz
- what is most appropriate management?
Open-angle glaucoma
Beta-1 and beta-2 Blockers
–reduces production of aqueous humor by ciliary body
What is the drug/drug class used to treat essential tremor (intention tremor)?
Propranolol - nonselective betablocker
Which do each of the foramina drain?
- Foramen of Magendie
- Foramina of Luschka
- Foramen of Monro
- 4th ventricle to subarachnoid space and central canal (1 of 3 exits)
- 4th ventricle to subarachnoid space (2 of 3 exits)
- Lateral ventricles to third ventricle
45 year old female presents with burning pain in her right leg. PMH of open comminuted right tibial fracture 3 months ago. she reports:
joint stiffness, regular muscle spasms. Mild edema
increased hair growth over affected area. What is dx?
Complex regional pain syndrome type 1 --continued pain out of proportion to injury --allodynia --joint stiffness --localized edema --increase hair growth --vasospasm (type 2 presents the same way but as has defined evidence of nerve damage)
A parkinsons patient is undergoing deep brain surger y to disable one of the neural circuits involved in the pathophysiology of his illness.
What two possible structures can be inactivated?
Subthalamic nucleus
Globus pallidus interna
25 year old Caucasian female presents with diminished visual acuity and decreased color perception. Pt states she first noticed general exercise-induced weakness and frequent episodes of urinary incontinence beginning four months prior to this episode.
What is the dz? what is the related HLA sub-type? what is immunotherapy?
what is a physical test/finding you can perform?
Multiple Sclerosis
- -females 20-40
- -weakness of limbs, spasticity, parethesis, diplopia, visual blurring, ataxia, bladder dysfunction
- -HLA-DR2
- -Tx: Interferon-B
Lhermitte’s sign = forward neck flesion = electric shock-like sensations down back through limbs
What is the use of Zolpidem and what is a notable side effect?
nonbenzodiazepine hypnotic that is used in the treatment of insomnia
a/w with parasomnias (bizarre behaviors that occur during sleep the patient is unaware of/has no recollection of) - sleepwalking
58 yr old pt presents w worsening weakness in arms and general fatigue for past three months. Fasciculations on neck. Hyperreflexia and atrophy arm muscles.
what is most likely diagnosis?
Amyotrophic lateral sclerosis
–degeneration of anterior horns of spinal cord
=present with muscle weakness and atrophy along with upper and lower motor neuron signs
20 yr old pt presents with altered mental state and convulsions. roommate says she took alot of an unknown medication. Tachycardia, widened QRS. Large pupils with slow reactivity, gag reflex is minimal, no response to auditory stimuli.
what was the most likely drug?
Tricyclic antidepressant
—inhibits reuptake of NE, serotonin
- -3C’s
1. Cardiotoxicity (tachycardia, hypotension, arrhythmias)
- CNS toxicity - sedated
- antiCholinergic
53 year old pt presents with vertigo. nausea, right-sided hearing loss, tinnitus. What is most likely found in patient’s inner ear?
Meniere’s disease = accumulation of endolymph in the membranous labyrinth
pt with parkinsons shows presents after being recently prescribed new medication. reports that meds improve her tremors but complains of difficulty initiating movement
what is the most likely drug/mechanism
Benztropine - Anti-cholinergic
What is the use and classification of tranylcypromine?
MAO inhibitor - sometimes used to treat depression
others: Phenelzine, Selegiline, Resagiline
How are Ependymomas and Medulloblastomas similar? how do you distinguish them?
Both are rumors that compresses the fourth ventricle and causes hydrocephalus
Ependymomas - arise from ependymal cells that line 4th ventricle, perivascular pseudorosettes
Medulloblastoma - arises from CEREBELLUS - small blue cells and Homer-Wright rosettes (halo of cells surrounding central ball-like arrangement filled w fibers)
55 year old presents with acute dysphagia, hoarseness, voice changes. uvula deviates right, diminished gag reflex. What is the embyro origin of the involved structure?
Myelencephalon - X, IX are located in lateral medulla
—-develops in to medulla
identify dz:
46 year old male presents with 5 week hx of worsening ataxia and involuntary muscle contractions. progressive memory loss, difficulty concentrating. EEG shows periodic sharp waves on slow background
what part of the brain does this effect?
Creutzfeldt-Jakob Disease
- -progressive dementia with myoclonus
- parenchymal vacuolation due to misfolded protein proliferation
affects: Entire Cerebrum
What are some adverse effects of Electroconvulsive therapy?
Confusion
Short-term memory loss
After nerve laceration, on what level should the affected nerve be reattached?
Perineurium - connective tissue layer that encases multiple neurons
What are the nerves involved with the lacrimation reflex? (ie tears from noxious stimulus)
stimulus sensed by CNV-1
tear production - CNVII
identify dz:
24 yr old at 20 weeks gestation present for ultrasound: fetus has small cerebellar vermis + enlargement of the fourth ventricle
what are addn’l findings
Dandy-Walker
- -presence of cysts near internal base of skull
- -cystic dilation of 4th ventricl and hypoplasia of cerebellar vermis
–causes hypotonia, delayed motor development, ataxia, intellectual disability
What is the location of dysfunction?
61 year old w “balance problems” - unsteady when walking in the dark. transient blurring of her visual field when attempting to make quick movements. Wide-based gait w deviation to the right. Craniosacral lesion, Greater wing of sphenoid is sup on right.
Vestibular dysfunction
- -unsteadiness when walking in dark/uneven ground
- -deviation of walking to side of affected ear.
- wide based gait, reduced stride length
What are the two components of pain sensation?
what type of fibers are in each
- paleospinothalamic
- slow C fibers
- chronic, diffuse, burning pain - Neospinothalamic
- fast A fibers
- -newer pain
32 year old pt w ataxia, dysarthria, dysmetria (nose to finger test), nystagmus, and peripheral neuropathy
what is dx? inheritance?
Spinocerebellar ataxia
—autosomal dominant inheritance
–4th decade w ataxia, dysarthria, dysmetria, nystagmus
What is the appropriate prophylaxis treatment for recurrent, severe migraine headaches?
Amitriptyline,
propranolol, timolol, divalproex, sodium valproate, topiramate
32 female w involuntary pauses and slurs in her speech, twitching eye, and hand tremor that worsens with movement. Last month she developed severe eye pain and numbness in left arm that resolved spontaneously. MRI shows periventricular lesions.
what is the dz and which cells are affected
Multiple sclerosis = Charcot’s triad (SIN = Scanning speech, Intention tremor, Nystagmus)
–targets oligodendrocytes - cells that produce myelin for the CNS
Where is location of lesion:
78 yr old w atrial fibrillation, htn presents with flailing movements of his right arm and leg. Woke up w terrible headache
infarct of PCA - damage the subthalamic nucleus = Contralateral Hemiballismus
55 year old w 30lb weight gain (used to be health conscious), inappropriate sexual comments, difficuly naming a watch and pencil, memory recall is intact
- what is dz
- what are bx findings
- what are imaging findings?
- Frontotemporal dementia (mean onset 55-60)
- Silver staining tau protein aggregates
- Temporal and frontal lob atrophy
identify dz:
autopsy: alpha-synuclein protein deposits and little cortical brain atrophy
Lewy body dementia
–rapid onset dementia w lost of variation in cognition day-to-day
Visual hallucinations
34 year old female w gradual hearing loss. Rinne shows bone conduction is hear longer than air conduction in both ears
what is most likely dz? what are additional findings?
Otosclerosis - loss of stapedial reflex
(involuntary muscle contraction that occurs in middle ear in response to high-intensity sound or when the person starts to vocalize)
