Neuro Flashcards
Radial Nerve function
Extension of wrist arm and finger joints below shoulder! Forearm supination, thumb abduction.
Injury or Radial N
At passage through supinator canal (due to repetitive pronation/supination, direct trauma, or sublexation of radius)
Features or Fragile X
Neurobehavioral problem
Prominent forehead and chin
large ears
long, narrow face
Large testis
hyperlaxity of joints in hand
Cytogenic: small gap near tip of log arm of X chr
Fragile X Syndrome
X linked mutation of FMR1 gene
Huntington Disease
CAG trinucleotide repeats of huntington gene
Leads to gain of function mutation which is responsible for transcription repression via histone deacetylation
Cause of acute hypertensive intracerebral hemorrhage
Charcot-Bouchard aneurysm (chronic hypertension leads to progressive arteriolar hyalinization and fibrinoid necrosis)
Often involves deep structures (basal ganglia, thalamus, pons)
AVM
Most common cause of intracranial hemorrhage in children
Phenytoin
Seizure medication (blocks voltage gated sodium channels in neurons)
Side effects:
- gingival hyperplasia
- ataxia and nystagmus
- disruption of folic acid metabolism (megaloblastic anemia)
- p450 inducer
- coarse facial features, hirsutism
- fetal hydantoin syndrome
Locus Ceruleus
Located at posterior rostral pons near lateral floor of 4th ventricle
Responsible for producing almost all NE in brain
Ataxia-Telangiectasia
cerebellar ataxia
telangiectasia
sinopulmonary infections
mutation of ATM gene (AR) responsible for DNA Break Repair
cerebellar atrophy
Pink MacConkey agar
organisms that ferment lactose (e.coli, Klebsiella, Enterobacter)
Narcolepsy
Cataplexy (loss of muscle tone, abnormal facial movements)
Hypocretin-1 deficiency in CSF
REM sleep latency <15 min
Recurrent lapses into sleep multiple times within the same day at least 3*/week for 3 months
Cluster Headache
Behind one eye
15-90 minutes
Nasal congestion and lacrimation
Tension Headache
stress, band-like pattern (b/l), bull tight, persistent
Muscle tenderness
Femoral Nerve Block
At inguinal creases, anesthetizes skin and muscles of anterior thigh, femur, and knee
Gerstmann syndrome
- Agraphia (inability to write)
- Acalculia (inability to do math)
- finger agnosia
- left-right disorientation
Stroke of angular gyrus of dominant parietal lobe
s-100 positive tumors
Schwannoma and melanoma (derived from neural crest)
Wilson Disease
AR mut in ATP7B, hinders hepatocellular copper transport
Reduced secretion of ceruloplasmin and decreased secretion of copper
Copper, a pro-oxidant, causes hepatocellular injury
Neuro involvement includes movement abnl and psych symptoms
Rings around iris
HIV-associated dementia
- subcortical dementia (attention/memory problems, executive dysfunction)
- due to inflammatory activation of microglial cells
Intranuclear acidophilic inclusions
HSV
Intranuclear basophilic inclusion
CMV
Vitamin E Def neuro symptoms
Mimics Friedreich Ataxia
Loss of position and vibration sense
Loss of DTR
Ataxia
Friedreich Ataxia
AR degenerative dz
Loss of proprioception and vibration sense (damage to dorsal columns)
Ataxia (loss of spinocerebella tract)
Spastic weakness (loss of lateral corticospinal tract)
Hypertrophic cardiomyopathy
Kyphoscoliosis
high arched feet
Vitamin A Toxicity
Acute: nausea, vomiting, vertigo, double vision
Chronic: alopecia, dry skin, lyperlipidemia, hepatotoxicity, hepatosplenomegaly, visual difficulties pailledema
Teratogenic: microcephaly, cardiac anomalies, fetal death
Niacin deficiency
Pellagra (3 D’s)
- Dementia
- Dermatitis
- Diarrhea
Wernicke Encephalopathy
Chronic Thiamine deficiency (alcoholics)
- Opthalmoplegia
- Ataxia
- Confusion
Hemorrhage and necrosis of mammillary bodies
Baseline erythrocyte transketolase activity low
tx: thiamine supplementation with glucose infusion
Axonal Reaction
Change seen in neuronal body after axon is severed
- cellular edema
- nucleus displaced to periphery
- Nissl substance fine, granular, and dispersed throughout cytoplasm
Most common side effect of levodopa/carbidopa
Anxiety and agitation
N. meningitidis virulence factor that underlies disease severity
Lipooligosaccharide
endotoxin
Length and time constant
- Length constant: measure of how far along an axon electrical impulses can propogate without requiring active regeneration by ion channels
- Time constant:
measure of time it takes for membrane potential to respond to membrane permeability
demyelination decreases length constant and increases time constant
Nerve responsible for sensation at suprapubic and gluteal region
Iliohypogastric nerve (L1 root)
Often injured during appendectomy
Common Peroneal Nerve
responsible for ankle dorsiflexion, eversion and toe extension
Sensory to lateral leg and dorsal foot
Damage (compression or fracture of lateral neck of fibula) leads to foot drop
Diabetic mononeuropathy
CNIII central ischemia
Ptosis, down and out gaze, normal light and accomodation
Berry aneurysm of COW
Often seen in ADPKD
Rupture causes subarachnoid hemorrhage
Epidural hematoma from
fracture of temporal bone and tear of middle meningeal artery
Medulloblastom
sheets of primitive cells and many mitotic figures
Located in cerebellum (vermis)