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