Neurology Flashcards
What would you see in an ACA infarct?
Contralateral motor and sensory loss of lower limbs
Where is glioblastoma tumor located?
Cerebral cortex (frontal, temporal etc)
Where is meningioma tumor located?
It is from arachnoid cells, external, and benign
What can cause parinaud syndrome?
Germinomas of the pineal gland (also in gonads and mediastinum)
What presents with parinaud syndrome, precocious puberty, and obstructive hydrocephalus?
Germinomas of pineal gland (histologicall similar to seminomas)
What is parinaud?
No conjugate vertical gaze due to lesion in superior colliculi
What presents with unilateral headache and associated with rhinorrhea and periorbital pain?
Cluster headache; MC in men
What levels do you see lateral horn in?
T1 - L2
What do lower spinal cord segments look like?
Bigger ventral horn (more gray less white)
What do upper spinal cord segments look like?
More white less gray
What happens in age related macular degeneration wet?
Bleeding due to choroidal neovascularization
What is the diagnosis? Grayish green subretinal membrane and hemorrhaging.
Wet age related macular degeneration
Where is meyer’s loop?
Temporal lobe
Where is upper optic radiation?
Parietal lobe
What does the huntington mutation cause?
GOF mutation that causes histone deacetylation
What chromosome is mutated with VHL?
Chromosome 3 (remember 3 letters in VHL)
What gets damaged in noise induced hearing loss?
Stereocilia of organ of corti
What does succinylcholine cause?
Life threatening hyperkalemia
What happens to CN III function in diabetic neuropathy?
Ocular motion lost but accommodation intact because only central part is affected and the parasympathetic fibers are on the outside
What is located in the internal capsule?
Corticospinal tract
What is a 5mm cavity in the brain?
Small lacunar infarct from lipohyalnois and microemboli
What do use for bradycardia in inferior wall MI?
Atropine
What do you see ring enhancing lesions?
Toxoplasma, brain abscesses (complication of bacterial endocarditis from S. aureus usually), CNS lymphoma
Why do Friedreich ataxia people get ataxic symptoms?
Mutation in frataxin (binds iron) that impairs mitochondrial functioning and causes degeneration of myelinated axons
What does friedreich ataxia affect?
Dorsal root ganglia, spinocerebellar tract, corticospinal tract, dorsal column –> spinal cord atrophy
What is a key presentation of Friedreich ataxia?
Wide-based gait with difficulty maintaining balance in 5-15 yo
How do you tell myasthenia gravis and lambert eaton apart?
Myasthenia has diplopia, dysarthria etc whereas lambert eaton is more likely to present with proximal muscle weakness and autonomic symptoms (dry mouth, impotence etc) and minimal change with AchE inhibitors
What causes halos around light, vision worse after dark room (eye dilation)?
Closed angle glaucoma
What are two key findings for Wallenburg?
Dysphagia and dysarthria; nucleus ambiguus lesions are specific for it
How do you tell CN III palsy from INO?
Convergence is normal in INO
What is a calcified cystic mass with thick brownish fluid high in choelsterol?
Craniopharyngioma
How old is a child who can use utensils and copy a circle?
About 3 years old
What is a bilateral wedge shaped necrosis parallel to longitudinal fissures in hypoxic ischemic encephalopathy?
Watershed infarct
What is the MCC of aseptic meningitis?
Enteroviruses
What is the MCC of lobar hemorrhage in adults >60yo?
Cerebral amyloid angiopathy particularly in parietal and occipital lobes
Where is area postrema located?
Dorsal surface of medulla near caudal end of 4th ventricle
When do microglia move to area of infarct/ischemia?
3-5 days after injury and then astrocytes form scars
Which tracts does Vitamin b12 affect?
Lateral corticospinal and dorsal columns
What do you do if someone is above 40degree celsius?
This is hyperpyrexia. Lower temperature with cold blankets and then give anti-pyretics
What is a major side effect of halothane?
Hepatic necrosis (inc AST, ALT, prolonged PT, shrunken liver)
What part of Wernicke Korsakoff is irreversible?
Memory loss
What causes IVH in neonates?
Fragile germinal matrix bleeding
Where is broca’s area located?
Lower frontal lobe
What happens if you get pure internal capsule stroke?
Pure motor weakness in arms, leg, face
What innervates the posterior part of external auditory meatus?
Vagus
What innervates the inner part of tympanic membrane?
Glossopharyneal
What type of tremor happens with certain actions and improves with alcohol?
Essential tremor
How do you treat an essential tremor?
Primidone, Propranolol
What is the treatment for status epilepticus?
1st line is benzodiazepines then give phenytoin. Phenobarbital if they are seizing still.
What do you see cortical atrophy as well as caudate and putamen atrophy?
Huntington
What does PCA stroke cause?
Homonymous hemianopia with macular sparing (MCA doesn’t spare macula)
What is the time constant?
Time it takes for a change in membrane potential
What is the length constant?
How far conduction travels before it dissipates
What does myelination do time and length constant?
Decreases time constant and increases elngth constant
What do you see anti-yo, hu, P/Q antibodies in?
Paraneopalstic cerebellar degeneration
What is paraneoplastic cerebellar degeneration?
Immune response against tumor cells that cross react with purkinje neuron antigens. Associated with lung cancers. Causes dysarthria, visual problems, ataxia
What is the diagnosis? Muscle rigidity, fever after surgery under inhaled anesthetics?
Malignant hyperthermia
Who gets malignant hyperthermia?
Those who inherit a defect in ryanodine receptor that causes large amounts of Ca to be released from SR
What does malignant hyperthermia present with?
Muscle rigidity, tachycardia, HTN, hyperkalemia, myoglobinuria, fever
What type of meningits? Elevated protein, normal glucose, lymphocytes
Viral meningitis
What is associated with polyhadamnios?
Anencephaly and GI obstruction
How does entacapone work?
Prevents L-dopa degradation and increases quantity entering the brain
What is the diagnosis? Ipsilateral pain/weakness of shoulder, miosis, ptsosis.
Pancoast tumor
What does hepatic encephalopathy deplete?
Glutamate and alpha-ketoglutrate (because it is used in neurons to detoxify accumulated glutamine; use alpha KG to convert it to glutamate)
How do mu receptors work?
Increase potassium efflux and close Ca channels
What ciliary epithelium do?
Produce aqueous humor
What targets ciliary epithelium?
Timolol (targets beta receptor)
What are the short acting benzos?
Triazolam, Alprazolam, Oxazepam
What side effects do you see with short acting benzos?
Less sedation but more withdrawal
How do you opioid analgesics affect the gallbladder?
Cause sphincter of oddi smooth muscle contraction causing biliary colic
What happens to albumin in hepatic necrosis?
Remains the same since it has a long half life; only changed with end stage liver disease
What ion contributes to resting membrane potential?
Mostly K and some Na
Which way does chloride flow?
Into the cell despite negative potential
What is Naloxone?
Mu antagonist
What presents with transient numbness and tingling that onsets suddenly and disappears in 20 minutes?
TIA
Where do the cerebral hemishperes and lateral ventricles come from?
Telencephalon (which comes from the prosencephalon)
Where do the third ventricle and thalamus come from?
Diencephalon (which comes from the prosencephalon)
Where do the aqueduct and mdibrain come from?
Mesencephalon (which also comes from the mesencephalon aka midbrain)
Where do the upper part of the fourth ventricle, pons, cerebellum come from?
Metencephalon (which comes from rhombencephalon)
Where do the lower part of fourth ventricle and medulla come from?
Myelencephalon (which comes from rhombencephalon)
Where do PNS neurons and Schwann cells come from?
Neural crest
What is the confirmatory test for neural tube defects?
AchE
What is anencephaly associated with?
Polyhydramnios and maternal diabetes type I
What is Dandy Walker malformation associated?
Hydrocephalus and Spina bifida
What is wallerian degeneration?
Degeneration distal to injury and proximal axon retraction
What is the gene associated with holoprosencephaly?
SHH
What fuses to form mutlinucleated giant cells in the CNS in HIV patients?
Microglia
Which nerve fibers are unmyelinated?
Autonomic postganglionic and C fibers
What are the sensory corpuscles?
Merkel: deep static touch, position, slow
Meissner’s: fine/light touch, position, fast
Ruffini: stretch of skin, slow
Pacinian: vibration, pressure, fast
What nucleus is involved with stress and panic?
Locus cereleus because NE increases in anxiety
What neurotransmitters are implicated in huntington’s?
Decreased GABA and Ach
In what disease did Ach increase?
Parkinson’s
How does NE promote sleep?
SCN makes NE which stimulates pineal gland to make melatonin
What causes rapid eye movement in REM?
PPRF
What is Papez’s circuit?
Cingulate –> hippocampus –> fornix –> mamillary body –> thalamus
What are the inputs to the cerebellum?
Middle cerebellar peduncle: contralateral cortex
Inferior cerebellar peduncle: ipsilateral proprioception
What are the outputs of the cerebellum?
Superior cerebellar peduncle: contralateral cortex (via deep nuclei)
Deep nuclei: : dentate, emboliform, globose, fastigial (lateral to medial)
What are the trinucleotide repeats in each disease?
Fragile X: CGG
Friedreich: GAA
Huntington: CAG
Myotonic dystrophy: CTG
What are amygdala lesions associated with?
HSV-1
What presents with hyperorality, hypersexuality, disinhibited behavior? Where is the problem?
Kluver-bucy
In the amygdala
What presents with agraphia, alcalculia, finger agnosia, left right disorientation?
Gertsmann syndrome
Problem in left parietal - temporal cortex
How to tell PPRF lesion from frontal eye field lesion?
PPRF looks away from lesion
FEF look toward lesion
If you correct hypernatremia too fast what happens?
Cerebral edema and herniation
Where is the infarct: contralateral hemiparesis, decreased contralateral proprioception and tongue deviating ipsilaterally?
ASA (anterior spinal artery)
Where is the infarct most likely if you see dysphagia and hoarseness?
PICA - Lateral medullary syndrome (Wallenburg): because nucleus ambiguus effects are specific to it
Where is the infarct most likely if you see facial paralysis?
AICA - Lateral pontine syndrome
Where is the second MC location of berry aneurysms?
Post. communicating
What symptoms do you see if there is an aneurysm of posterior communicating?
CN III palsy
What do you see transtentorial herniation and CN III palsy with?
Epidural hematoma
What is a lobar intraparenchymal hemorrhage caused by?
Cerebral amyloid angiopathy
What do yo see at 3-5 days after stroke?
Macrophages
What do you see 12-48 hours after stroke?
Necrosis + neutrophils
What is the inheritance pattern of SMA?
AR
What has hammer toes and pes cavus, kyphoscoliosis?
Friedreich Ataxia
What degenerated in friedreich?
Large myelianted sensory neurons in DRG, dorsal columns
What is it called when you have hemisection of spinal cord?
Brown Sequard
What can cause Horner’s besides Brown sequard and pancoast?
Late stage syringomyelia
What did S2, 3, 4 do?
Erection, penile and anal sensation
What are the reflexes?
Biceps: C5
Triceps: C7
Patella: L4
Achilles: S1
What may cause primitive reflexes to reappear in adults?
Frontal lobe lesions
What is the galant reflex?
Stroking along one side of spine while newborn is face down causes lateral flexion of body towards that size
When do the primitive reflexes disappear?
Moro: 3 mos
Rooting: 4 mos
Palmar: 6 mos
Plantar: 12 mos
What two nerves are at cerebellopontine angle?
CN VII, VIII
What does superior colliculi do?
Conjugate vertical gaze
What is a common cause of Parinaud?
Pinealoma or Germinoma in pineal gland
Where are the cranial nerve nuclei?
Midbrain: 3, 4
Pons: 5, 6, 7, 8
Medulla: 9, 10, 12
Spinal cord: 11
What is nucleus ambiguus?
CN 9, 10, 11. Does motor innervation of pharynx, larynx, and upper esophagus
What is nucleus solatrius?
CN 7, 9, 10. Does sensory information (taste, baroreceptors, gut distension)
What nerve go through jugular foramen?
CN 9, 10, 11
Which way does jaw deviate in CN V motor lesion?
Toward
What causes hyperacusis?
Stapedial nerve injury
What hearing do you lose first?
High frequency
What is prebyopia?
Decrease in focusing ability during accommodation due to sclerosis and decreased elasticity
What fixes your myopia?
Presbyopia because it doesn’t focus as well so it allows the image (which normally lands before retina) to land on the retina
What causes open angle glaucoma?
Primary is unclear. Secondary is blocked trabecular meshwork from WBC (uveitis), RBC (vitreous hemorrhage), retinal elements (retinal detachment)
What causes closed angle glaucoma?
Primary: lens pushes against iris causing fluid to build up which pushes iris towards cornea blocking trabecular meshwork
Secondary: hypoxia induces vasoproliferation in iris
What do you not give for acute closure in closed angle glaucoma?
Epinephrine
What is the path of nerves to cause miosis (parasympathetic)?
Edinger westphal –> CN III –> ciliary ganglion –> short ciliary –> pupillary sphincter
What is the path of nerves to cause mydriasis (sympathetic)?
Hypothalamus (posterior) –> through spinal cord –> exit at T1 –> superior cervical ganglion –> plexus around internal carotid –> through cavernous sinus –> enters orbit as long ciliary —> pupillary dilator
What is Marcus Gunn pupil?
Lack of afferent so no response when light shone in affected eye
What are retinal breaks more common with?
High myopia and preceeded by posterior vitreous detachment (flashes and floaters) w/ eventual monocular loss –> SURGICAL EMERGENCY)
Why do you get nystagmus in abducting eye with MLF lesion?
The LR on the abducting eye overfires to cause the not functioning eye to move
What does right INO mean?
Right eye is paralyzed
What are the findings of MS?
IgG in CSF, oligoclnal bands, periventricular plauqes
When do symptoms of MS worsen?
After hot shower or post workout (ie with heat exposure)
What is the albuminocytologic disassociation and what is it with?
It is increased CSF protein with normal cell count. Seen with AIDP/ Guillan Barre
What is ADEM?
Multifocal perivenular inflammation and demylination after measles of VZV or vaccine (rabies, smallpox)
What is wrong in charcot marie tooth?
Can’t make proteins that are involved in peripheral nerve or myelin sheath function/structure
What does charcot marie tooth present with and what is its inheritance?
AD; Scoliosis and pes cavus
What is adrenoleukodystrophy?
X-linked; can lead to coma/death and adrenal gland crisis. Can’t metabolize very long chain FA
Where do partial seizures MC occur?
Medial temporal lobe
What are two heart drugs you can use for migraine headaches?
Propranolol, CCB
How do you tell peripheral from central vertigo?
Via positional testing:
Peripheral: delayed nystagmus
Central: immediate nystagmus
What is the mutation in Sturge-Weber?
Noninherited mutation in GNAQ. anomal of neural crest derivatives
What do you see a leptomeningeal angioma with?
Sturge Weber
What does VHL inhibit?
HIF
Which tumor do you see psammoma bodies with?
Meningioma
Where does Schwannoma most commonly occur?
Cerebellopontine angle
What do you see secondary polycythemia with?
Hemangioblatoma because it can produce EPO
What has biphasic growth pattern?
Schwannoma
Where is oligodendroglioma most commonly occur?
Frontal lobes
What has a chicken wire capillary pattern?
Oligodendroglioma
Where does hemangioblastoma most commonly occur?
Cerebellum
Where does colloid cyst occur?
Third ventricle
What is a highly malignant tumor in kids?
Medulloblastoma
What tumor is found in the fourth ventricle?
Ependymoma
Where do kids tumors occur mostly?
Under the tentorium cerebelli (ie where cerebellum etc are)
What herniates in an uncal herniation?
Medial temporal lobe
How do cholinomimetics treat glaucoma?
Cholinomimetics contract ciliary muscle to open up trabecular meshwork
What is latanoprost?
PGE analog that increases aqueous humor outflow. Causes darkening of iris
What two side effects does tolerance not develop to with opioid analgesics?
Constipation and Miosis
What is butarphanol?
Mu partial agonist and kappa agonist. Less respiratory depression than full agonists.
Which opiod analgesic does nalaxone not reverse?
Butarphanol
What is a major side effect of Tramadol?
Sertonin Syndrome
How does Tramadol work?
Very weak opiod agonist and inhibits 5HT and NE reuptake
What is the 1st line treatment of eclampsia seizures?
MgSO4
What are major side effects of Valproate?
Fatal hepatotoxicity, spina bifida. Also tremor and weight gain
What is the drug of choice for partial seizures?
Carbamazepine
What is 1st line epilepsy drug in neonates?
Phenobarbital
How does Gabapentin work?
Inhibits Vca channels
What is contraindicated in porphyria?
Barbiturates
What are the short acting benzos?
Alprazolam, triazolam, midazolam, oxazepam
What do you have less risk of drowsiness with but more withdrawal?
Short DOA barbiturates (Alprazolam, Triazolam, Oxazepam, Midazolam)
What do you give for bedwetting
Desmopressin
What are the inhaled anesthetics?
Halothane and “fluranes” and NO
How does Dantrolene work?
Prevents release of Ca from SR in skeletal muscle
What is the toxicity for halthone?
MAJOR hepatotoxicity
What is the toxicity for methoxyflurane?
Nephrotoxicity
What is the toxicity for enflurane?
Proconvulsant
What is thiopental?
IV barbiturate anesthetic High potency and lipid solubility. Decreases cerebral BF. Used for induction of anesthesia and short surgical procedures
What redistributes to skeletal muscle and fat?
Thiopental
What are the side effects of Midazolam?
Severe postop respiratory depression. Decreased Bp and anterograde amnesia
What is Midazolam?
IV benzo anesthetic used for endoscopy. Used adjunctively with gaseous anesthetics and narcotics
What is ketamine?
PCP analog that acts as dissociative anesthetic. Blocks NMDA receptors. CV stimulant. Increases cerebral BF
What are the side effects of ketamine?
Disorientation, hallucination, bad dreams
What are the IV opioid anesthetic?
Morphine, Fentanyl
What is propofol?
Potentiates GABA. Used for ICU sedation, rapid anesthesia and short procedures. Less postop nausea than thiopental.
What are the local anesthetics?
Esters (procaine, cocaine, tetracaine)
Amines (lidocaines, mepivcaine, bupivcaine) - have two “I”
How do local anesthetics work?
Block Na channels especially activated ones so effective for rapidly firing neurons
What can local anesthetics be given with?
Vasoconstrictors (Epinephrine usually) –> enhances local acion - dec bleeding, inc anestheisa by dec systemic concentration
What happens with local anesthetics in acidic tissue?
Alkaline ones are charged and can’t penetate membrane so need to give more
What type of nerves do anesthetics block?
Small > large; myelinated > unmyelinated (size preference over myelination)
What is the order of sensory loss in local anesthetics?
Pain > temperature > touch > pressure
What are the toxicities for local anesthetics?
CNS excitation
What is a toxicity with bupivicaine?
Severe CV toxicity
What are neuromuscular blocking drugs specific for?
Motor nicotinic receptor
What are the side effects of depolarizing neuromuscular blockers?
Hypercalcemia, hyperkalemia, malingant hyperthermia
What are the neuromuscular blocking agents?
Depolarizing: Succinylcholine
Non-depolarizing: “urium” and “uronium” and Tubocurarine
How do non-depolarizing neuromuscular blocking agents work?
Competitive antagonists of Ach
What do antimuscarinics improve with parkinsons?
Tremor and rigidity BUT NOT BRADYKINESIA
What is amantadine for?
Increases dopamine release and for influenza A and rubella
What is the toxicity for amantadine?
Ataxia
What is a toxicity with L-dopa and carbidopa?
“On-off” due to varying drug levels. Dyskinesia while on and akinesia while off.
How does Selegiline work?
MAO-B inhibitor (MAO-B preferentially metabolizes dopamine over 5HT and NE)
What are common side effects of L-dopa?
Anxiety and agitation
What are the side effects of Sumatriptan?
Coronary vasospasm (contraindicated in CAD and Prinzmetal), mild tingling
What blocks morphine tolerance?
Ketamine through its inhibitor action on NMDA receptors preventing glutamate from binding
What pathway connects hypothalamus and pituitary gland?
Tuberoinfundibular
What would infarct of anterior medial pons show?
Dysarthria and contralateral ataxic hemiparesis
Where does CN V exit?
Middle cerebellar peduncle at lateral aspect of mid pons
What does Vitamin E deficiency show?
Dorsal column, spinocerebellar tract, and peripheral nerve degeneration
How does pramipexole work?
Dopamine agonist so stimulates dopamine receptors
What are glial cells?
Ependymal, oligodendrocytes, astrocytes
What cells are synpathophysin positive?
Neurons
What is the terminal sulcus?
Divides anterior 2/3 of tongue from posterior 1/3
What is the foramen cecum i the tongue?
Midline at terminal sulcus (divides anterior 2/3 of tongue from posterior 1/3)
What presents with rock hard eye, halos, and sudden pain in the eye?
Acute closure glaucoma
What is cerebral amyloid angiopathy?
Elderly; causes intracerebral hemorrhage that would present with headache and focal neurologic deficits
What does it mean if there is a high arteriovenous concentration gradient after administering an anesthetic gas?
It means more peripheral uptake from arterial blood and less to the brain. Means it would have a slow onset of action.
What is Pentazocine?
Opioid narcotic with partial agonist and weak antagonist activity. If given with morphine it will have antagonist effects and can worsen withdrawal symptoms.
What are neurofibromas a proliferation of?
Schwann Cells (elongated, wavy cells with spindle nuclei)
Also fibroblasts and neurites
What is the mechanism of action of phenobarbital?
Facilitate GABA action by increasing duration of Cl channel opening (barbiDURate)!
What causes ataxia, wide based gait, nystagmus and head tilting?
Cerebellum medial lesion
Hemorrhage where would present with pinpoint pupils, loss of horizontal gaze, quadriparesis, decrebrate posturing and rapidly evolving coma leading to death within hours?
Pontine hemorrhage
Hemorrhage where would produce contralateral sensory loss, aphasia, temporary homonymous hemianopia?
Thalamic hemorrhage
What is vasogenic edema?
“Extracellular”
Fluid shifts from intra to extracellular
Neoplasm or infarction cause it (destroy endothelial tight junctions)
Increases ICP
What is cytotoxic edema?
“Intracellular”
Fluid shifts from extra to intracellular
From ischemia that impairs Na/K ATPase –> fluid shifts in
If hyperreflexia and tongue deviation on protrusion toward side of lesion, what part of medulla is the lesion in?
Pyramids because the hypoglossal nerve comes off the pyramids and the corticospinal tracts decussate there
Where does CN III come off?
Above pons
What are the complications of succinylcholine?
Hyperkalemia, hypercalcemia, malignant hyperthermia
