Neuro Flashcards
frontal lobe lesion sx
disinhibition and deficits in concentration, orientation, judgement
may have reemergence of primitive reflexes
difficulty “describing the difference between a watch and a ruler”
front eye fields lesion sx
eyes look towards brain lesion (away from side of hemiplegia)
paramedian pontine reticular formation lesion sx
eyes look away from lesion (toward side of hemiplegia)
MLF lesion sx
internuclear ophthalmoplegia
- impaired adduction of ipsilateral eye
- nystagmus of contralateral eye w/ abduction
**MS
dominant parietal cortex lesion sx
agraphia (inability to write)
acalculia (loss of ability to do simple math)
finger agnosia (loss in the ability to distinguish, name, or recognize the fingers)
left-right disorientation
**Gerstmann syndrome
nondominant parietal cortex lesion sx
agnosia (inability to interpret sensations and hence to recognize things) of contralateral side of the world
**hemispatial neglect syndrome
bilateral hippocampus lesion sx
anterograde amnesia (inability to make new memories)
basal ganglia lesion sx
tremor at rest, chorea, athetosis
**parkinson, huntington, wilson’s disease
subthalamic nucleus sx
contralateral hemiballismus (intermittent flinging movements on one side)
bilateral mammillary bodies lesion sx
wernicke-korsakoff syndrome (confusion, ataxia, nystagmus, ophthalmoplegia), memory loss, congabulations, personality changes
bilateral amygdala lesion sx
kluver-bucy syndrome (disinhibited behavior - hyperphagia, hypersexuality, hyperorality)
**HSV-1 encephalitis
dorsal midbrain lesion sx
parinaud syndrome (vertical gaze palsy, pupillary light-near dissociation, lid retraction, convergence-retraction nystagmus)
**pinealoma
reticular activating system (midbrain) lesion sx
reduced levels of arousal and wakefulness
**coma
cerebellar hemisphere lesion sx
intention tremor, limb ataxia, loss of balance
**cerebellar hemispheres are located laterally –> affect lateral limbs
cerebellar vermis lesion sx
truncal ataxia (wide-based, “drunken sailor” gait)
nystagmus
**vermis is located centrally –> affects central body
red nucleus (midbrain) lesion sx
decorticate (flexor) posturing - lesion above red nucleus
decerebrate (extensor) posturing - lesion at or below red nucleus
histologic features of brain 12-24 hours after ischemic event
24-72 hours
3-5 days
1-2 weeks
> 2 weeks
12-24: eosinophilic cytoplasm + lack of Nissl bodies + pyknotic nuclei (red neurons - shrunken)
24-72 hours: necrosis + neutrophils
3-5 days: macrophages
1-2 weeks: reactive gliosis (astrocytes) + vascular proliferation
> 2 weeks: glial scar
MCA stroke sx
contralateral paralysis and sensory loss in face and upper limb
dominant hemisphere: aphasia
nondominant hemisphere: hemineglect
ACA stroke sx
contralateral paralysis and sensory loss in lower limb
urinary incontinence
lenticulostriate artery stroke sx
contralateral paralysis
absence of cortical signs (neglect, aphasia, visual field loss)
ASA stroke sx
contralateral paralysis of upper and lower limbs
decreased contralateral proprioception
ipsilateral hypoglossal dysfunction (tongue deviates ipsilaterally)
**medial medullary syndrome
PICA stroke sx
dysphagia, hoarseness, decreased gag reflex, hiccups
vomiting, vertigo, nystagmus
decreased pain and temp from contralateral body and ipsilateral face
ipsilateral horner, ataxia, dysmetria
**lateral medullary syndrome (wallenberg)
blood supply of medial medulla
ASA
blood supply of lateral medulla
PICA
blood supply of medial pons
basilar
blood supply of lateral pons
AICA
blood supply of medial midbrain
PCA
blood supply of lateral midbrain
PCA
medial cranial nerves and where they come out of
3, 4 - midbrain
6 - pons
12 - medulla
lateral cranial nerves and where they come out of
5, 7, 8 - pons
9, 10, 11, 12 - medulla
AICA stroke sx
paralysis of face
decreased lacrimation, salivation, taste from anterior 2/3 tongue
decreased pain and temp contralateral body and ipsilateral face
ipsilateral horner, ataxia, dysmetria
**lateral pontine syndrome
basilar artery stroke sx
quadriplegia
loss of horizontal eye movements
**medial pontine syndrome (‘locked in” syndrome)
PCA stroke sx
contralateral hemianopia (blindness in 1/2 visual field) with macular sparing
damage to the arcuate fasciculus causes what
conduction aphasia
- fluent speech
- good comprehension
- poor repetition
transcortical motor
transcortical sensory
transcortical mixed
transcortical motor: affects frontal lobe around Broca but spares Broca
transcortical sensory: affects temporal lobe around wernicke but spares wernicke
transcortical mixed: broca, wernicke, arcuate fasciulus remain intact, surrounding watershed areas affected
what is a tonic-clonic (grand mal) seizure
alternating stiffening and movement
postictal confusion, urinary incontinence, tongue biting
what is a myoclonic seizure
quick, repetitive jerks
patient with involuntary, rhythmic jerking of an extremity that lasts 1 minute, remains fully alert
simple focal (partial) onset seizure
dopamine, acetycholine, and GABA levels in huntington’s
increased dopamine
decreased Ach and GABA
histo and gross findings alzheimers
- AB amyloid plaques in gray matter
- neurofibrillary tangles made of tau
- hirano bodies (intracellular eosinophilic proteinaceous rods in hippocampus)
inclusions in frontotemporal dementia are made of what
hyperphosphorylated tau (pick bodies) or ubiquitinated TDP-43
sx CJD
rapidly progressive dementia with myoclonus (startle myoclonus) and ataxia
sx pseudotumor cerebri (idiopathic intracranial hypertension)
increased ICP with no obvious findings on imaging
headache, tinnitus, diplopia, no change in mental status
what is charcot-marie-tooth disease
sx
mutation
defective production of proteins involved in structure and function of peripheral nerves or myelin sheath
foot deformities (pes cavus, hammer toe)
LE weakness (foot drop)
sensory deficits
PMP22 gene duplication
what is sturge weber syndrome
sx
congenital nonhereditary anomaly of neural crest derivatives due to somatic mosaicism of activating mutation in one copy of GNAQ gene
port-wine stain in CN V1/V2 distribution
ipsilateral leptomeningeal angioma –> seizures
intellectual disability
early onset glaucoma
sx tuberous sclerosis
H: hamartomas in CNS and skin
A: angiofibromas
M: mitral regurgitation
A: ash-leaf spots
R: cardiac rhabdomyoma
M: mental retardation
A: renal angiomyolipoma
S: seizures, shagreen patches
sx von hippel lindau dz
hemangioblastomas in retina, brainstem, cerebellum, spine
angiomatosis
bilateral renal cell carcinoma
pheochromocytomas
sx NF1
cafe au lait spots
intellectual disability
cutaneous neurofibromas
lisch nodules (pigmented iris hamartomas)
optic gliomas
pheochromocytomas
seizures
treatment for ALS
rilouzole
sx brown sequard syndrome
1) ipsilateral loss of all sensation at level of lesion
2) ipsilateral LMN signs at level of lesion
3) ipsilateral UMN signs below level of lesion
4) ipsilateral loss of proprioception, vibration, light touch below level of lesion
5) contralateral loss of pain and temp below level of lesion
sx friedreich ataxia
staggering gait
frequent falling
nystagmus
DM
hypertrophic cardiopmyopathy
CN V motor lesion sx
jaw deviates towards side of lesion
CN X lesion sx
uvula deviates away from lesion
CN XI lesion sx
weakness turning head to contralateral side of lesion
CN XII lesion sx
tongue deviates toward side of lesion
compare upper and lower motor neuron facial nerve lesions
UMN:
- lesion located in the connection between the motor cortex and the facial nucleus in the pons
- affects contralateral lower muscles of facial expression
- forehead is spared
LMN:
- lesion located anywhere along CN VII after facial nucleus in pons
- affects ipsilateral upper and lower muscles of facial expression
- forehead is affected
first line treatments for alzheimers
donepezil, rivastigmine, galantamine, memantine
first line treatment for huntington dz and moa
tetrabenazine
inhibits vesicular monoamine transporter (VMAT) which decreases dopamine vesicle packaging and release
memantine MOA
NMDA receptor antagonist
first line treatment for ALS and moa
riluzole
decreases neuron glutamate excitotoxicity
thiopental MOA and indications
barbiturate (facilitates GABAa)
anesthesia induction, short surgical procedures
ketamine effect on cerebral blood flow
increased
MOA local anesthetics
lidocaine, mepivacaine, bupivacaine, ropivacain
block Na+ channels
what is the order of nerve blockade with local anesthetics
small diameter fibers > large diameter fibers
myelinated fibers > unmyelinated fibers
size predominates over myelination
small myelinated fibers > small unmyelinated fibers > large myelinated fibers > large unmyelinated fibers
MOA succinylcholine
ACh receptor agonist –> produced sustained depolarization and prevents muscle contraction
MOA atracurium, cisatracurium, pancuronium, rocuronium, tubocurarine, vecuronium
competitive ACh antagonist
baclofen MOA and indication
GABA-B agonist in spinal cord
muscle spasticity, dystonia, MS
cyclobenzaprine MOA and indication
acts within CNS mainly at brain stem
muscle spasticity
dantrolene MOA and indications
prevents Ca2+ release from sarcoplasmic reticulum by inhibiting ryanidine receptor
malignant hyperthermia and neuroleptic malignant syndrome
tizanidine MOA and indications
a2 agonist
muscle spasticity, MS, ALS, cerebral palsy
