USMLE Step 1 Neuro Flash Cards – Flashcards
Unlock all answers in this set
Unlock answersquestion
Parkinson's Disease
answer
-Loss of dopaminergic neurons of Sub. Nigra pars compacta -Lewy bodies (composed of alpha synuclein - intracellular accumulation) -resting tremor, rigidity, akinesia, and postural instability
question
Huntington's Disease
answer
Aut Dom trinucleotide repeat. -Chorea, dementia, depression, and aggression -Caudate loss, decreased ACh and GABA -Neuronal death via NMDA-R binding and glutamate toxicity
question
Kluver Bucy Syndrome
answer
-Bilateral amygdala lesion -hyperorality, hypersexuality, disinhibited behavior -associated with HSV-1
question
Fontal Lobe Lesion
answer
Disinhibition and deficits in concentration, orientation, and judgment -remergence of primitive reflexes
question
Paramedian pontine reticular formation lesion
answer
eye looks away from lesion
question
Frontal eye fields lesion
answer
eye look toward lesion
question
Central Pontine myelinolysis
answer
-D/t rapid correction of hyponatremia or low Mg -acute paralysis, dysarthria, dysphagia, diplopia (Conjugate gaze palsy), loss of consciousness, hypotension -involves pontine basis
question
Lesion in subthalamic nuclues
answer
-contralateral hemiballismus
question
Conduction aphasia
answer
-Arcuate fasciculus lesion (connects broca's and wernickes area) -poor repetition but normal fluent and intact comprehension
question
Lateral striate artery stroke
answer
-contralateral hemiparesis/hemiplegia -common location of lacunar infarcts, secondary to unmanaged HTN
question
ASA Stroke
answer
-Lateral cortical spinal, Medial lemniscus, and caudal medulla affected -CL hemiparesis of lower limbs -CL decreased proprioception -IL tongue deviation
question
PICA Stroke
answer
-Lateral medulla (symp fibers, vestibular nuc, spinal trigeminal nuc, lat corticospinal tract, and nucleus ambiguus), inf cerebellar peduncle -Vomiting, vertigo, nystagmus -Limbs face have dec pain and temp sensation -dysphagia, hoarseness, dec gag reflex -IL horner's syndrome -ataxia, dysmetria
question
AICA Stroke
answer
-Lateral pontine (symp, vestibular nuc, spinal trigeminal nuc, cochlear nuc, facial nuc), middle and inf cerebellar peduncles -Vertigo, vomiting, nystagmus -Paralysis of face, dec lacrimation, salivation, dec corneal reflex, dec taste from ant 2/3 of tongue -Dec pain and temp from face -IL hearing loss -IL Horner's syndrome
question
Epidural Hematoma
answer
-Rupture of middle menial artery -d/t fracture of temporal bone -Rapid inc in intracranial pressure - see transtentorial herniation and CN III palsy -doesn't cross suture lines but can cross falx/tentorium
question
Subdural hematoma
answer
-Bridging veins rupture -slow bleeding seen in alcoholics, elderly, shaken baby, and blunt trauma -crosses suture lines but not falx/tentorium
question
Subarachnoid hemorrhage
answer
-Rupture of aneurysm (ADPKD/Ehrlos Danlos/Marfans) or AVM -Worst HA of life -Bloody spinal tap (xanthochromic) -Risk of vasospasm d/t blood breakdown and rebleed
question
Intraparenchymal Hemorrhage
answer
-Usually d/t systemic HTN also d/t amyloid angiopathy or vasculitis or neoplasm -usually in BG or internal capsule
question
Normal Pressure Hydrocephalus
answer
-No increase in subarachnoid space volume -expansion of ventricles compresses fibers of corona radiata and -Triad of incontinence, dementia, and ataxia
question
Communicating hydrocephalus
answer
-decreased CSF absorption by arachnoid villi which can lead to increased intracranial P, papilledema, and herniation
question
Obstructive Hydrocephalus
answer
-Causes by a structural block of CSF circulation w/in the ventricular system
question
Hydrocephalus ex vacuo
answer
appearance of increased CSF d/t atrophy of brain -normal intracranial P
question
Poliomyelitis
answer
-From poliovirus via fecal-oral route -replicates in oropharynx and small intestine and spreads via blood to CNS -destruction of anterior horn cells in SC, leading to LMN destruction -malaise, fever, nausea, abdominal pain, sore throat -signs of LMN lesions - atrophy/fasiculations, etc -CSF has lymphocytes, inc protein, normal glucose -virus in stool or throat
question
Werdnig Hoffman disease
answer
-aka infantile spinal muscular atrophy -Aut Rec -presents as floppy baby and tongue fasiculations -degeneration of anterior horn cells, LMN only
question
ALS
answer
-LMN and UMN signs with no cognitive/sensory problems -Can be d/t superoxide dismutase 1 defect -presents as fasiculations with eventual atrophy -Riluzole treatment can modestly lengthen surival
question
Tabes Dorsalis
answer
-Degeneration of dorsal columns and dorsal roots d/t tertiary syphilis -impaired proprioception and locomotor ataxia -associated w/charcot's joints, shooting pain, argyll roberston pupils, absence of DTRs, positive Romberg, and sensory ataxia at night
question
Freidrich's ataxia
answer
-Aut Rec trinucleotide repeat (GAA) -Frataxin gene on Chrm 9 -leads to impairment in mitochondria fxn -Staggering gait, frequent falling, nystagmus, dysarthia, pes cavus, hammer toes -Hypertrophic cardiomyopathy causes death -presents in childhood w/kyphoscoliosis
question
Brown Sequard Syndrome
answer
-IL UMN Signs -IL Dorsal column signs -CL Pain and Temp loss -IL Loss of all sensation at level of lesion -LMN signs at level of lesion -if above T1, presents w/Horners syndrome
question
What's in cavernous sinus?
answer
CN III, IV, V1, V2, VI, Cavernous part of int. carotid artery -Connects w/internal jugular vein -Cavernous sinus syndrome (d/t mass effect - ophthalmoplegia, ophthalmic and maxillary sensory loss)
question
UMN Facial Lesion
answer
CL paralysis of lower face
question
Bell's Palsy
answer
Complete destruction of facial nucleus or LMN lesion (IL paralysis of upper and lower face). Bell's also has inability to close eye -associated with AIDS, Lyme disease, Herpes Simplex, Sarcoidosis, tumor, diabetes
question
Retinitis
answer
Retinal necrosis plus edema -> atrophic scar
question
Iritis
answer
Systemic Inflammation (Reiter's Syn)
question
Near Vision
answer
Ciliary Muscle contracts (zonular fibers relax and lens relaxes causing it to be more convex) -light focuses in front of retina -treat w/biconcave lens
question
Distant Vision
answer
Ciliary muscle relaxes (Lens flattens) -light focuses behind retina -treat w/convex lens
question
Aging effects on eyes
answer
-sclerosis and decreased elasticity causes presbyopio (no near vision)
question
Retinal artery occulusoin
answer
acute painless mononuclear loss of vision -pale retina w/cherry red macula d/t having its own blood supply (choroid artery)
question
Open/wide angel Glaucoma
answer
-obstructed outflow -associated w/myopia, increased age, AA race -silent/painless
question
Narrow angle glaucoma
answer
-obstruction of flow b/t iris and lens -pressure builds up behind iris -very pain, dec vision, rock hard eye, frontal HA
question
Cataract
answer
-bilateral, painless opacification of lens leads to dec vision -RF: age, smoking, alcohol, sunlight, galactosemia, galactokinase def, diabetes (sorbitol), infection, trauma
question
Papilledema
answer
increased intracranial pressure -elevated optic disk w/blurred margins, bigger blind spot
question
CN III Interior vs Exterior Lesions
answer
-Interior = Output to ocular muscles - affected by vascular disease d/t decreased diffusion to interior. sxms = ptosis, down and out, nonreactive pupils -Exterior: Parasympathetic output - affected by compression (PCA berry aneurysm/uncal herniation). See blown pupil
question
Age related macular degeneration
answer
-degeneration of macula causes loss of central vision -Dry ARMD is slow and d/t fat deposits and causes gradual dec in vision -wet ARMD is rapid and d/t neovascularization
question
Alzheimer's Disease
answer
-Widespread cortical atrophy with dec ACh -Senile plaques: extracellular beta-amyloid core; and can lead to amyloid angiopaty and intracranial hemorrhage -Neurofibrillary tangles: intracellular phosphorylated tau protein, an insoluble cytoskeletal elements -Down syn pts have inc risk -familial genes: APP, presenilin 1 and 2, ApoE4 (late onset)
question
Pick's Disease
answer
-Dementia, aphasia, parkinsonian aspects, changes in personality -frontotemporal atrophy with sparing of parietal lobe and posterior 2/3 of superior temporal gyrus -Pick bodies - intracellular, aggregated tau protein
question
Lewy Body Dementia
answer
-Parkinsonism w/dementia and hallucinations -alpha-synuclein defect
question
Creutzfeldt-Jakob Disease
answer
Rapidly progressive dementia w/myoclonus -spongiform cortex -prion disease PrPc -> PrPsc
question
Multiple Sclerosis
answer
-autoimmune inflammation and demyelination of CNS -Disease mediated by Th1 and CD4 T Cells that respond to myelin antigens and release IFN gamma to activate Macrophages and IL-2 to activate CTLs -Type 4 Hypersensitivity -Sxms: Scanning speech, intention tremor, incontinence, internuclear ophthalmoplegia, nystagmus, hemiparesis, hemisensory -Inc protein (IgG) in CSF. Oligoclonal bands are diagnostic. -MRI shows periventricular plaques w/perservation of axons and reactive gliosis -Tx: beta-interferon
question
Guillain-Barre Syn
answer
-Inflammation and demyelination of peripheral nerves and motor fibers of ventral roots -Causes symmetric ascending muscle weakness beginning in distal lower extremities -Autonomic fxn may be severely affected -Findings: inc CSF protein w/normal cell count. Inc protein can lead to papilledema -associated w/infections (Camplyobacter jejuni or herpes virus) d/t molecular mimicry, inocluation, or stress -Endoneural inflammatory infiltrate -Most patients survive
question
Progressive multifocal leukoencephalopathy
answer
-Demyelination of CNS d/t destruction of oligodendrocytes -associated w/JC virus seen with <200 CD4 -Bizzare astrocytes and intranuclear inclusions of oligodendrocytes
question
Acute Disseminated Encephalomyelitis
answer
-Multifocal perivenular inflammation and demyelination after infection (chickenpox, measles) -T Cell mediated hypersensitivity
question
Metachromatic Leukodystophy
answer
-Aut Res lysosomal storage disease -d/t arylsulfatase A deficiency -build up of sulfa tides leads to impaired production of myelin sheath
question
Charcot-Marie Tooth Disease
answer
-Hereditary nerve disorders related to the defective production of proteins involved in the structure and fxn of peripheral nerves or the myelin sheath -often presents w/weakness of foot dorsiflexion d/t common peroneal n. involvement
question
Migraine
answer
-unilateral HA, 4-72 hrs of pulsating pain w/nausea, photophobia, or phonophobia -with or without aura of sums including visual/sensory/speech disturbances -D/t irritation of CN V and release of substance P, CGRP, vasoactive peptides -Tx: Propranolol, NSAIDs, sumatriptan
question
Tension HA
answer
-bilateral, >30 minutes of steady pain -Not aggravated by light or noise; no aura
question
Cluster HA
answer
-Unilateral, repetitive brief HAs -characterized by periorbital pain associated w/IL lacrimation, rhinorrhea, Horner's Syn -More common in men -Tx: inhlaed Oxygen, sumatriptan
question
Sturge-Weber Syn
answer
-congenital disorder w/port wine stains (typically in V1 ophthalmic distribution), IL leptomeningeal angiomas, pheochromocytoma -Can cause glaucoma, mental retardation, seizures -occur spontaneously
question
Tuberous Sclerosis
answer
-HAMARTOMAS -Hamartomas in CNS or skin, Adeno sebacem, mitral regurg, ash-leaf spots, cardia rhabdomyoma, aut dom, mental retardation, increase risk of astrocytoma, renal angiomyolipoma, seizures
question
Neurofibromatosis Type 1
answer
-Cafe au-lait spots, Lisch nodules (pigmented iris hamartoms), optic gliomas, neurofibromas in skin, pheochromocytomas, scoliosis -Aut Dom, 100% penetrant -Mutated NF-1 gene on Chromosome 17
question
Von-Hippel-Lindau Disease
answer
-Cavernous hemangiomas in skin, mucosa, organs -Bilateral renal cell carcinoma -hemangioblastomas in retina, brain stem, cerebellum -Pheochromocytomas -Aut Dom mutated tumor suppressor VHL on Chromosome 3
question
Glioblastoma
answer
-Found in cerebral hemispheres -Can cross corpus callosum -stain astrocytes for GFAP -pseudopalisading pleomorphic tumor cells, border central necrosis and hemorrhage
question
Meningioma
answer
-usually adults in convexities of hemispheres and parasagittal sinuses -arise from arachnoid cap cells external to brain -spindled cells in whorled pattern and psomma bodies
question
Schwannoma
answer
-Adults, Schwann cell origin -often localized to CN VIII -> acoustic scwannoma -usually found at cerebellopontine angle, S100 positive -Bilateral schwannoma in neurofibromatosis type 2
question
Oligodendroglioma
answer
-Usually in frontal lobes in adults -chicken wire capillary pattern w/ oligodendrocytes in fired egg shape (round nuclei w/clear cytoplasm) -often calcified
question
Pituitary Adenoma
answer
-Most commonly prolactinoma -Bitemporal hemianopia (d/t P on optic chiasm) -Rathke's Pouch
question
Pilocytic astrocytoma
answer
-Usually in children in posterior fossa -GFAP positive -Rosenthal fibers - eosinophilic, corkscrew fibers -cystic and solid (gross) -biphasic growth pattern (densely fibrillar and micro cystic cellular)
question
Medulloblastoma
answer
-Highly malignant cerebellar tumor usually in kids -A form of primitive neuroectodermal tumor (PNET) -Can compress 4th ventricle, causing hydrocephalus -Rosettes or perivascular pseudorosettes -Small blue cells
question
Ependymoma
answer
-Ependymal cell tumors most commonly found in 4th ventricle in kids -Can cause hydrocephalus -characteristic perivascular pseudorosettes w/nuclear free zone
question
Hemangioblastoma
answer
-most often cerebellar -associated with Von-Hippel-Lindau syndrome when found with retinal angiomas -Can produce EPO->secondary polycythemia
question
Craniopharyngioma
answer
-benign childhood tumor, confused w/pituitary adenoma -most common childhood supratentorial tumor -derived from Rathke's pouch -calcification is common
question
Uncal Herniation Signs
answer
-IL dilated pupil/ptosis (strecthing of CN III) -CL homonymous hemianopia (compression of IL PCA) -IL paresis (compression of CL crus cerebri) -Duret hemorrhages- paramedian artery rupture - caudal displacement of brain stem
