Term
What elements of the CNS/PNS are derived from each of the following?
1) Neuroectoderm
2) Neural crest
3) Mesoderm |
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Definition
1) CNS neurons, Ependymal cells (inner lining of ventricles that make CSF), Oligodendroglia and Astrocytes
2) Schwann cells and PNS neurons
3) Microglia, like Macrophages, originate in Mesoderm) |
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Term
| Describe the process of Wallerian degeneration |
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Definition
Axon injury.....Neuron degeneration distally, axonal reaction (cellular swelling, dispersal of Nissl) proximally.
**Nissl (RER) is in cell body and dendrites, not axons** |
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Term
| What is the function of astrocytes and microglia? |
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Definition
1) Astrocytes (Neuroectoderm)
- Physical support, repair, K+ metabolism, removal of excess NT, maintenance of BBB.
- Reactive gliosis following injury (GFAP marker)
2) Microglia (Mesoderm)
- CNS phagocytes with small, irregular nuclei and little cytoplasm
- Scavenger cells that respond to damage by differentiating into large phagocytes (infected microglia fuse to form giant cells in HIV) |
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Term
| What is myelin and how is it produced in the CNS and PNS? |
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Definition
CNS- oligodendrocytes (neuroectoderm: many axons per cell)
- Predominant glial cell in white matter (destroyed in MS)
- Fried egg appearance on H & E
PNS- schwann cells (neural crest: one axon per cell)
- Promote axon regeneration and conduction velocity via saltatory conduction (Na+ channels in nodes of R)
- Destroyed in Gjillain-Barre |
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Term
| What cell types are destroyed in MS and Guillain-Barre, respectively? |
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Definition
Demyelinating conditions.
MS= Oligodendrocytes (CNS)
GB= Schwann cells (PNS)- specifically the endoneurium surround nerve fiber layers within a fascicle. |
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Term
| What type of cell gives rise to an acoustic neuroma? |
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Definition
| Schwannoma in internal acoustic meatus (CN VIII) |
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Term
Describe the location and sensation associated with each of the 4 sensory corpuscle types?
1) Free nerve ending
2) Meissner's
3) Pacininan
4) Merkel disk |
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Definition
1) C fibers (slow, unmyelinated) and A-delta (fast, myelinated)
-Found in skin, epidermis and some viscera
- Sense PAIN and TEMPERATURE
2) Large, myelinated fibers on Glabrous (hairless) skin
- Fast-adating: Position sense, dynamic fine touch
3) Large, myelinated fibers on deep skin layers, ligaments and joints
- Vibration and pressure sensation
4) Large, myelinated fibers found in hair follicles
- Slow-adaptive: Position sense, static touch (shapes, edges and texture) |
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Term
| Describe the basic components of a peripheral nerve (anatomically). |
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Definition
1) Epineurium- Dense connective tissue that surround entire nerve (fascicles and blood vessels)
2) Perineurium= Permeability barrier
- Surrounds a fascicle of nerve fibers (must be re-joined in surgery for limb reattachment)
3) Endoneurium
- Invests single nerve fiber layers within a fascicle (Guillain-Barre)
4) Nerve fibers
- Individual nerve fibers within endoneurium of a fascicle |
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Term
| What aspects of the peripheral nerves must be surgically re-joined in microsurgery for limb re-attachment? |
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Definition
Perineurium (Permeability barrier)
- Surrounds a given nerve fascicle and separates it from adjacent vessels (Vessel + fascicles are in Epineurium) |
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Term
Where are each of the following Neurotransmitters synthesized?
1) NE
2) Dopamine
3) 5-HT
4) ACh
5) GABA |
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Definition
1) Locus ceruleus (stress and panic center)
- Increased in anxiety and decreased in depression
2) VTA and SNc
- Increased in Schizophrenia and decreased in PD and depression
3) Raphe nucleus
- Decreased in anxiety and depression
4) Basal nucleus of meynert
- Decreased in AD and HD and Increased in REM sleep
5) Nucleus accumbens (reward center, pleasure, addiction, fear)
- Decreased in anxiety and HD |
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Term
| What NT are increased/decreased in anxiety? |
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Definition
1) Increased
- NE (locus ceruleus)
2) Decreased
- 5-HT (Raphe)
- GABA (NA) |
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Term
| Describe the anatomical structure of the BBB. |
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Definition
Analagous to glomerulus, but without fenestrations in endothelium and with Astrocyte foot processes rather than Podocytes.
1) Tight junctions between non-fenestrated capillary endothelial cells
2) BM
3) Astrocyte foot processes |
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Term
| What areas of the brain contain capillary fenestrations that allow passage of blood components? |
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Definition
Cicumfrential regions.
**BBB is permeated by hypothalamic inputs/outputs**
1) Area postrema- vomiting after chemo
2) OVLT- osmotic sensing with projections to SON and PVN for ADH regulation
3) Neurohypophysis- ADH release |
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Term
| Describe the mechanism of vasogenic edema? |
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Definition
| Infarction and/or neoplasm damages capillary endothelial tight junctions, rending BBB permeable. |
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Term
| What are the major functions of the hypothalamus? |
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Definition
wears TAN HATS
1) Thirst and water balance
2) Adenohypophysis control
3) Neurohypophysis release of ADH/SON Oxytocin/PVN
4) Hunger
5) Autonomic control
6) Temperature regulation
7) Sensual urges
Inputs: OVLT (osmolarity), Area postrema (emetics) |
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Term
| What are the major divisions of they hypothalamus and their functions? |
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Definition
1) Lateral- Hunger (inhibited by leptin)
- destruction produces anorexia and failure to thrive
- "zap lateral, shrink laterally"
2) Ventromedial- Satiety (stimulated by leptin)
- Destroyed by craniopharyngeoma (hyperphagia)
- "zap ventromedial, grow medially"
3) Anterior- Cooling, pArasympathetics
- A/C, anterior cooling
4) Posterior
- Heating, sympathetic
- "zap Posterior, you become Poikilothermi (cold blooded like snake)"
5) SCN- circadian rhythms |
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Term
| Where is ADH and oxytocin produced? |
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Definition
ADH= SON of hypothalamus
Oxytocin= PVN of hypothalamus |
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Term
| What hormones are stored in the neurohypophysis? |
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Definition
| Recieves hypothalamic projections from SON (ADH- water retention) and PVN (oxytocin- quick birth) |
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Term
| What are the inputs and outputs of the 4 major thalamic nuclei? |
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Definition
Relays all ascending sensory information BUT olfaction
1) VPL- Spinothalamic and dorsal columns/medial lemniscus (input) to primary somatosensory cortex (output)
- Pain, temperature, fine touch, vibration, proprioception
2) VPM- Trigeminal and gustatory pathway (input) to primary somatosensory cortex (output)
- Face sensation and taste
3) LGN- CN II (input) to Calcarine sulcus (output)
- vision
4) MGN- Superior olive and IC of tectum (input) to Auditory cortex of temporal lobe (output)
- auditory |
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Term
| What are the famous "5 F's" of the limbic system? What are the structures? |
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Definition
Feeding, Fleeing, Fighting, Feeling and Fucking
Cingulate, Hippocampus, Fornix, Mammillary bodies and Septal nucleus |
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Term
| What are the major cerebellar nuclei? |
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Definition
1) Deep (L to M)- Dentate, Emboliform, Globose, Fastigial (Don't Eat Greasy Foods)
2) Lateral- voluntary movement of extremities
3) Medial- balance, truncal coordination, ataxia
- when injured, tend to fall to ipsilateral side. |
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Term
| What are the major inputs/outputs of the cerebellum? |
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Definition
1) Inputs
- Middle peduncle: Contralateral cortical input (mossy fibers via pontocerebellar path)
- Inferior peduncle: Ipsilateral proprioceptive input (climbing fibers from superior olivary nucleus in medulla synapse with purkinje cells)
2) Outputs (sensory feedback to contralateral cortex to modulate movement)
- Purkinje fibers output to deep nuclei, which send output to cortex via superior peduncle |
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Term
| Describe the direct dopaminergic pathway of the basal ganglia. |
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Definition
Short: Facilitates movement by inhibiting Gpi, and preventing it from inhibiting the thalamocortical projections.
1) SNpc stimulates D1 receptors in Putamen, which send inhibitory signals to the GPi
2) The GPi sends inhibitory projections to thalamus (so inhibiting it, will prevent thalamic inhibition and facilitate movement) |
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Term
| Describe the indirect dopaminergic pathway of the basal ganglia. |
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Definition
Short: Inhibits movement by inhibiting STN (inhibiting thalamocortical connections).
1)SNc inhibits D2 receptors in Putamen, thereby preventing their normal inhibition of Gpe
2) Without Gpe inhibition, the Gpe inhibits the STN, which normally stimulates the thalamus. |
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Term
Does stimulation of each of the following basal ganglia nuclei stimulate or inhibit movement?
1) GPi
2) GPe
3) STN
4) THalamus
5) D2 receptors in putamen |
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Definition
Remember, dopamine binds D1 and D2 receptors, stimulating and inhibiting the direct and indirect pathways, respectively.
1) Inhibition
- Direct pathway: When stimulated, the GPi inhibits the thalamus
2)Inhibition
Indirect: When stimulated, the GPe sends inhibitory signals to STN, thereby preventing thalamcortical activation
3) Stimulation
- Indirect: STN stimulates thalamocortical fibers
4) Inhibit
Indirect: Stimulation of D2 receptors will "inhibit" inhibition of GPe, thereby allowing it to inhibit the STN |
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Term
Which of the following is NOT a cardinal sign of Parkinson's Disease?
1. Intention tremor
2. Cogwheeling rigidity
3) Akinesia
4) Postural instability |
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Definition
1- It is a RESTING tremor
TRAP (Tremor, Rigidity, Akinesia, Posture)
Degeneration of dopaminergic neurons in SNpc with Lewy bodies (alpha syn-nuclein) |
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Term
| What is it called when a patient exhibits sudden, wild flailing of 1 arm +/- leg and what is the associated lesion? |
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Definition
Hemiballismus= contralateral STN lesion (usually a lacunar stroke in a patient with hypertension)
- You lose inhibition of thalamus via Gpe in indirect pathway |
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Term
hat type of movement is described by each of the following and what is its cause?
1) Sudden, jerky, purposeless movements
2) Sudden, wild flailing of 1 arm +/- 1 leg
3) Slow, writhing movements, especially of fingers
4) Sudden, brief muscle contractions
5) Sustained, involuntary muscle contraction |
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Definition
1) Chorea: basal ganglia lesion (Huntington's or Rheumatic fever)
2) Hemiballismus: contralateral STN lesion (lacunar stroke with hypertension)
3) Athetosis: Basal ganglia lesion (Huntington's)
4) Myoclonus (jerks or hiccups)
5) Dystonia (writer's cramp, blepharospasm) |
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Term
| What are the major types of tremors and how do they differ? |
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Definition
1) Essential/Postural: Autosomal dominant action tremor (worsens when holding posture)
- Self medicate with alcohol or use B-blockers
2) Resting- Most noticeable distally and common in PD.
3) Intention: Slow, zigzag motion when pointing toward a target
- Cerebellar dysfunction |
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Term
Match each of the following with the appropriate type of tremor.
1) Positive family history and treated with beta blockers
2) Cerebellar dysfunction
3) Parkinson's disease |
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Definition
1) Essential/postural tremor
2) Intention tremor
3) Resting tremor |
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Term
True or False:
Left leg paresis could be caused by a lesion of the right lateral motor strip. |
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Definition
False! It will be on the right, but legs are medial and hands are more lateral (mouth and tung are most lateral)
This lesion would likely cause left hemiparesis of hands and face. |
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Term
What area is lesioned in each of the following?
1) Hyperorality, hypersexuality and dis-inhibition of behavior
2) Dis-inhibition and deficits in concentration, orientation and judgment.
3) Spatial neglect of left side
4) Redeuced arousal and wakefulness (can be a coma)
5) Confusion, opthalmoplegia, ataxia, memory loss, confabulation and personality changes |
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Definition
1) Bilateral amygdala (Kulver-Bucy associated with HSV-1)
2) Frontal lobe
3) Right parietal lobe
4) RAS (midbrain)
5) Mammillary bodies (bilateral) in Wernike-Korsakoff syndrome (alcohol) |
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Term
| Why is thiamine deficiency dangerous for the nervous system? |
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Definition
Alocholic thiamine deficiency (B1: Beri Beri) is associated with Wernicke Korsakoff syndrome (atrophy of mamillary bodies of hypothalamus)
1) Wernicke encephalopathy
- confusion, ataxia and impaired eye movements
2) Korsakoff psychosis (sequele or 1)
- Memory loss, confabulation and personality changes. |
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Term
What area is lesioned in each of the following?
1) Resting tremor, chorea and/or athetosis
2) Intention tremor, limb ataxia (Left)
3) Truncal ataxia, dysarthria
4) Contralateral hemiballismus |
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Definition
1) Basal gnanglia
2) Left cerebellar hemisphere damage
- Cerebellar deep nuclei project to contralateral motor cortex, which eventually crosses again in the corticospinal ducussation (ipsilateral)
**hemispheres are lateral, and affect lateral limbs**
3) Cerebellar vermis (vermis is centrally located and affects central body)
4) STN- loss of thalamus inhibition via Gpe |
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Term
True or False:
A lesion of the left cerebellar hemisphere would produce a right intention tremor or leg ataxia |
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Definition
False- Will be ipsilateral
1) Left hemisphere projects to right motor cortex
2) Corticospinal tract crosses to left at pyramidal decussation
**Hemispheres are lateral, and affect "lateral limbs," while vermis is central, and affects "trunk"** |
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Term
What area is lesioned in each of the following?
1) Resting tremor, chorea and/or athetosis
2) Anterograde amnesia
3) Truncal ataxia, dysarthria
4) Eyes look to the right (side of lesion)
5) Eyes to left (away from lesion) |
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Definition
1) Basal ganglia lesion
2) Hippocampal lesion
3) Cerebellar vermis
4) FEF
5) PPRF |
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Term
| Describe the anatomical organization of eye movement control via the abducens nucleus to both eyes look "to the right" |
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Definition
Use right nucleus as an example (in pons)
Under control of ipsilateral PPRF, which receives input from contralateral FEF.
1) Sends ipsilateral abducens nerve to lateral rectus (right)
2) Sends interneuron to CNIII nucleus in midbrain on left via MLF.
- Post-synaptic neuron innervates medial rectus on left. |
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Term
| Why does lesion to the left FEF cause both eyes to turn to the left? |
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Definition
- Left FEF projects to contralateral PPRF
- Right PPRF controls right IV nucleus in pons.
- Right IV nucleus controls ipsilateral LR and contralateral MR muscles (turns eyes to the right).
- Without right PPRF, there is unopposed activity of the left PPRF, and eyes turn to the left. |
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Term
| What is the concern surrounding rapid correction of hyponatremia? |
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Definition
Central pontine myelinolysis (CPM)
When salt is missing, extracellular fluid is hypoosmolar, so cells absorb water (cerebral edema).
If salt comes back in too quickly, cells (and brain) shrink with damage to myelin sheaths!
You get acute paralysis, dysarthria, dysphagia, diplopia and loss of consciousness. |
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Term
| What is the concern surrounding rapid correction of hypernatremia? |
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Definition
Cerebral edema! Seizures and permanent brain damage.
When extracellular fluid is hypertonic, water flows out of cells.
To compensate, cells begin to produce osmotically active solutes.
When hypotonic saline is given, salt will flow back into cells and they will accumulate even more water. |
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Term
What type of aphasia is described by each of the following?
1) Non-fluent aphasia with intact comprehension (sentences are meaningful but hard to understand.
2) Fluent aphasia with impaired comprehension (wordy, but makes no sense)
3) Nonfluent aphasia with impaired comprehension
4) Poor repetition but fluent speech and intact comprehension. |
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Definition
1) Brocas (inferior frontal gyrus)
2) Wernicke's (superior temporal gyrus)
3) Global (both)
4) Conduction (arcuate fasciculus, which connects the two) |
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Term
| How does dysarthria differ from aphasia? |
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Definition
| Aphasia is higher-order issue (superior temporal of inferior frontal gyri), which dysarthria is a motor issue (seen in basal ganglia lesion). |
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Term
Hypoxemia of which artery fits each symptom?
1) Right leg hemiparesis
2) Left hand hemiparesis
3) Wernicke's aphasia
4) Left visual loss |
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Definition
1) Left Anterior cerebral artery (supply anteromedial surface, where medial motor strip is located).
2) Right middle cerebral artery (supplies lateral surface of motor strip, which means hands and face).
3) Also middle cerebral artery, which supplies superior temporal gyrus
4) Posterior cerebral artery (supplies posterior and inferior surfaces) |
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Term
| Why do patients get upper leg/upper arm weakness and defects in higher-order visual processing during hypotension? |
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Definition
Watershed zone infarcts
ACA:MCA junction (arm leg)
MCA:PCA junction (visual processing) |
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Term
| Describe how CO2 and O2 levels drive cerebral perfusion. |
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Definition
Normally driven by CO2, but also by O2 under severe hypoxia (Po2< 50 mmHg)
1) Cerebral perfusion pressure is directly related to PCO2 until PCO2> 90 mmHg, at which point CPP plateus.
- Increased CO2, means increased H+ (acidosis), and will trigger faster breathing via central chemoreceptors, in order to maintain perfusion
**therapeutic hyperventilation will decrease ICP by decreasing PCO2 (cerebral edema due to stroke or trauma)**
2) If PO2 drops below 50, peripheral chemoreceptors will be tripped. |
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Term
| Why might someone with high intracerebral pressure be breathing very quickly? |
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Definition
| ICP is directly related to PCO2, so if there is acidosis and cerebral edema, they might breathing quickly to get rid of CO2 and reduce ICP. |
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Term
| Describe the anatomical organization of the circle of willis (really...DO IT) |
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Definition
1) Anterior circulation (derived from internal carotids)
- Internal carotids give off PCOM before bifurcating into the MCA and ACA
- ACA on right and left eventually join to form anterior communicating artery.
2) Posterior circulation (derived from subclavian)
a) Subclavian arteries give rise to left and right vertebral arteries
b) Vertebral arteries give off PICA and Anterior spinal artery, before joining to form the Basilar artery
c) Basilar artery gives of AICA and then the SCA, before bifurcating into the right and left PCAs.
**PCAs communicate with MCA via PCOM** |
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Term
| Describe the effects of a stroke to the left MCA |
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Definition
MCA supplies
1) Motor cortex (upper limb and face)
- right-side paralysis
2) Sensory cortex (upper limb and face)
- Right loss of sensation
3) Wernicke's and Broca's area
- Global aphasia
**If lesion affects nondominant side (usually right), you can get hemineglect** |
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Term
| Describe the effects of a stroke to the left ACA |
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Definition
1) Motor cortex- lower limb
- right lower limb paralysis
2) Sensory cortex- lower limb
- right lower limb sensation loss |
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Term
| Describe the effects of a lacunar infarct to the lateral striate artery on the left. |
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Definition
LSA in part of anterior circulation and supplies striatum and internal capsule.
Lacunar stroke to LSA is common in unmanaged HTN.
Contralateral hemiparesis/hemiplegia |
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Term
| Why might a patient with uncontrolled hypertension present with loss of mobility of right side of body? |
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Definition
Lacunar infarct of left internal striate artery (internal capsule and striatum).
Contralateral motor loss common in uncontrolled hypertension. |
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Term
| What are the symptoms/signs associated with an infarction of left PICA? |
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Definition
Posterior circulation: first branches given off of vertebral arteries supplying the Lateral Medulla (Wallenberg's syndrome).
1) Vestibular nuclei (vomiting, vertigo, nystagmus)
2) Lateral spinothalamic tract (loss of pain, temperature on limbs and face)
3) Spinal trigeminal nucleus and NA (dysphagia, hoarsness and loss of gag reflex)
4) Sympathetic fibers (ipsilateral horner's)
5) Inferior cerebellar peduncle (Ataxia and dysmetria) |
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Term
Which of the following symptoms would NOT be found in lateraly medullary syndrome?
1) Vertigo
2) Ipsilateral horner's
3) Ataxia
4) Hoarsness
5) Decreased vibration sensation of contralateral body |
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Definition
5- Dorsal columns are NOT hit in Wallenberg
Remember, it his vestibular nuclei, spinal trigeminal nuclei, NA, sympathetic chain, inferior cerebellar peduncle and lateral spinothalamic tract.
Don't Pick (PICA) a Horse (Hoarsness) that Can't Eat (Dysphagia) |
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Term
| How would a lesion to the anterior spinal artery present? |
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Definition
ASA forms from junction of left and right vertebral arteries and supplies:
1) Lateral corticospinal tract
- Contralateral hemiparesis of lower limbs
2) Medial lemniscus
- Contralateral proprioception
3) Caudal medulla (hypoglossal)
- Ipsilateral deviation of tongue |
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Term
"Patient complaining of loss of fine touch and motor control of left lower limb. When they stick out their tongue, it deviates to the opposite side of the other symptoms"
What is your diagnosis? |
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Definition
ASA supplies hypoglossal nucleus, lateral corticospinal tract and medial lemniscus.
Ipsilateral tongue (hypoglossal) and contralateral sensation (medial lemniscus) and motor control (lateral conticospinal tract). |
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Term
| What is lateral pontine syndrome? |
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Definition
AICA stroke.
Facial droop means AICA's pooped (facial nucleus affects are specific)
1) Lateral Pons
- Vestibular nuclei (vomiting/vertigo)
- Facial nucleus (paralysis of face and taste on anterior 2/3)
- Spinal trigeminal (corneal reflex, pain/temp on face)
- Cochlear nuclei (ipsilateral hearing)
- Sympathetic fibers (ispsilateral horners)
2) Middle and inferior cerebellar peduncles |
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Term
| How can you most easily distinguish between PICA and AICA infarctions based upon clinical signs alone? |
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Definition
Lateral medullary syndrome and lateral pontine syndrome have a great deal of overlap, BUT
1) PICA (LMS) has NA (hoarsness and dysphagia)
"don't pick a (PICA) hoarse (hoarseness) that can't eat (dysphagia)"
2) AICA (LPS) has facial nucleus (paralysis of face with droop)
"Facial Droop means AICA's pooped" |
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Term
| What might be the clinical presentation of a left PCA stroke? |
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Definition
PCA= Occipital and visual cortex (contralateral)
- Right hemianopsia with macular sparing/central vision (compensatory supply by MCA of macula) |
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Term
| What are the common sites of Berry aneurysms and how do they present? |
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Definition
Lesions are typically aneurysms and not strokes
1) AComm (MOST COMMON)- impingement on cranial nerves with visual defects
2) PComm- CN III palsy (eye is down and out) |
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Term
| What are Charcot-Bouchard microaneurysms and where do they typically occur/rupture? |
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Definition
| Microaneurysms with chronic hypertension found in Basal Ganglia and Thalamus |
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Term
Which of the following is NOT associated with increased occurrence of Berry aneurysms?
1) APCKD
2) Ehlers-Danlos
3) Smoking
4) African american race
5) Hypothyroidism
6) Marfan's syndrome |
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Definition
They are associated with hypertension, and hypothyroidism produces hyPOtension.
ED and Marfan's syndromes have no collagen and fibrillin, so vessel integrity is compromised |
|
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Term
| What is the most common cause of the intracranial hemorrhage that presents as a "biconvex disc" on CT? |
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Definition
Epidural hematoma (can cross falx, tentorium)
- Caused by fracture of temporal bone, leading to rupture of middle meningeal artery (from maxillary artery)
- Rapid expansion under arterial pressures, with transtentorial herniation and CN III palsy. |
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|
Term
What is the most common cause of each of the following?
1) Epidural hematoma
2) Subdural hematoma
3) SAH
4) Intraparenchymal (hypertensive) hemorrhage. |
|
Definition
1) Ruptured middle meningeal artery due to temporal bone fracture.
- Rapid expansion from arterial presure
2) Rupture of bridging veins (slow bleed)
- Crescent shape hemorrhage that crosses suture lines with "midline shift"
3) Rupture of aneurysm (berry in Marfan's Ehlers-Danlos, ADPKD)
- Bloody or yellow tap
4) Systemic hypertension, amyloid angiopathy, vasculitis and neoplasm.
- Typically in basal ganglia and internal capsule |
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Term
| What are the worrisome complications of the intracranial hemorrhage associated with Ehlers-Danlos syndrome? |
|
Definition
SAH: yellow/bloody spinal tap from ruptured berry aneurysm.
2-3 days after
1) Vasospasm (blood breakdown, not visible on CT, but treat with nimodipine- non-dihydropyridine Ca blocker)
2) Re-bleed (visible on CT) |
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Term
| Why do you give a patient 1 day post-op SAH nimodipine? |
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Definition
| Non-dihydrodyridine Ca2+ blocker to prevent vasospasm and re-bleed. |
|
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Term
Which areas of the brain are most vulnerable to ischemic damage and what events occur at each of the following time points?
1) 12-48 h
2) 24-72 h
3) 3-5 d
4) 1-2 w
5) > 2 w |
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Definition
Irreversible after 5 minutes!
- Hippocampus, Neocortex, Cerebellum and Watershed areas.
1) Red neurons
2) Necrosis + PMNs
3) Macrophages
4) Reactive gliosis + vascular proliferation
5) Glial scarring |
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Term
| What are the major etiologies of ischemic brain damage? |
|
Definition
1) Atherosclerosis: form cystic cavity with reactive gliosis
2) Hemorrhagic stroke: caused by HTN, malignancy of anti-coagulation
3) Ischemic stroke: Emboli from A-fib, carotid dissection, patent foramen ovale or endocarditis
**GIVE TPA in 4.5 h**
4) TIA: Brief and refersible (<24 h) with focal ischemia |
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Term
True or False:
tPA is appropriate to give a patient with hypertension and evidence of a lacunar stroke, with bright areas on non-contrast CT, as long as it is <4.5 h after stroke. |
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Definition
False!
Bright areas are hemorrhage, so DON'T GIVE AN ANTI-COAGULANT |
|
|
Term
| Describe the basic venous drainage of the brain. |
|
Definition
Cerebral veins drain into the venous sinuses, which eventually enter the internal jugular vein.
1) Superior opthalmic vein and Cavernous sinuses are drained directly by transverse sinus
2) Superior saggital sinus drains CSF from arachnoid granulations
3) Inferior saggital sinus and great cerebral vein of Galen are drained by Straight sinus
4) Occipital, Sup. saggital and Straight sinuses meet at Confluence, which drains into Int. jugular vein via transverse (meeting cavernous) and sigmoid sinuses. |
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Term
| What is the appearance of a stroke on diffusion-weighted MRI and non-contrast CT at 1 and 36 hours? |
|
Definition
1) Diffusion-weighted MRI will be bright from 3-30 min, up until 10 days
2) Dark on non-contrast CT after 24h (bright indicates bleed!) |
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Term
| Describe the ventricular system of the brain. |
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Definition
CSF made by choroid plexus and reabsorbed by venous sinus arachnoid granulations (drained by superior saggital sinus)
- Lateral ventricles drain into 3rd ventricles via foramen of monroe
- 3rd drains into 4th via cerebral aqueduct
- 4th drains in SA space via Foramen of Luschka (lateral) and Magendie (medial) |
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Term
| What type of hydrocephalus is "wet, wobbly and wacky"? How does it occur? |
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Definition
Normal-pressure hydrocephalus (i.e. no obstruction)- common, reversible cause in elderly.
Results in increased volume in sub-arachnoid space, without pressure change.
Expansion disrupts fibers of corona radiata (Dementia, Ataxia and Urinary incontinence) |
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Term
| What is the difference between communicating and obstructive (non-communicating hydrocephalus? |
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Definition
1) Communicating
- Decreased CSF absorption by arachnoid villi, which can increase ICP, causing papilloedema and herniation (arachnoid scarring-post-mengitis can cause this)
2) Obstructive
- Structural blockage of CSF within ventricular system (aqueduct of syllvius stenosis by Arnold-Chiari II) |
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Term
| Why might a patient who recently suffered from meningitis present with papilloedema and evidence of herniation? |
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Definition
| Communicating hydrocephalus due to arachnoid scarring (increasing ICP because no CSF absorption). |
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Term
| What is Hydrocephalus ex vacuo? |
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Definition
Appearance of increased CSF in atrophy (Alzheimer's, advanced HIV, Pick's disease).
ICP is normal (communicating/obstructive) and no triad (normal pressure) is present |
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Term
What form of hydrocephalus is characterized by each of the following?
1) Reversible cause of dementia, urinary incontinence and ataxia in elderly.
2) Papilloedema and herniation following meningitis
3) Arnold chiari malformation
4) Chronic degenerative disease |
|
Definition
1) Normal Pressure hydrocephalus
- Expansion of volume without pressure, compressing corona radiata
2) Communicating hydrocephalus due to arachnoid villi scarring
3) Obstructive, non-communicating hydrocephalus
4) Hydrocephalus ex vacuo (apparent increase in CSF is due to atrophy of brain itself). |
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Term
| What is the most common location of a vertebral disc herniation? |
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Definition
| Nucleus pulposis herniates through annulus fibrosus (check with straight-leg test), usually between L5-S1 |
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Term
| How many spinal nerves are they and how do they exit? |
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Definition
31
8 cervical, 12 thoracic, 5 lumbar, 5 sacral and 1 coccygeal
1) C1-C7 exit through intervertebral foramina.
2) Others exit below vetebra |
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Term
| Describe the "lower extent" of the spinal chord in terms of fibers, subarachnoid space, ect. |
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Definition
Due an LP between L3-L5, at the level of the cauda equina
1) Chord goes to L1-L2
2) SAS extends to lower border of S2 |
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Term
| Describe the 4 basic tracts of the spinal chord. |
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Definition
1) Dorsal columns (pressure, vibration, touch, proprioception)
- Fasciulus gracillus (medial= lower body)
- Fasciculus cuneatus (lateral= upper body)
2) Lateral corticospinal (voluntary motor)
- Legs lateral and arms medial
3) Spinothalamic
- Pain and temp anterolaterally
4) Spinocerebellar |
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Term
True or False:
The legs are located laterally to the arms in the dorsal columns of the spinal chord. |
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Definition
False! dorsal columns are organized as you are (arms outside legs)
Fasculus gracilis (medial)= legs
Fasciulus cuneatus (lateral)= arms
Legs are Lateral in Lateral corticospinal tract, however, before it crosses in the medulla pyramids. |
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Term
| Describe the course of the dorsal column pathway (chord to cortex). |
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Definition
1) Cell body of 1st neuron in DRG enters spinal cord and ascends ipsilaterally in the dorsal column (legs are medial to hands)
2) Synapses in ipsilateral nucleus cuneatus or gracilis (medulla)
3) 2nd-order neuron ducussates in medulla and ascends contralaterally in medial lemniscus
4) 2nd order neuron synapses in VPL of thalamus
5) 3rd order neuron hits cortex. |
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Term
| Describe the course of the spinothalamic tract (chord to cortex). |
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Definition
1) Sensory nerve ending (C and A-delta fibers) with cell bodies in DRG enters spinal chord
2) 1st neuron synapses in ipsilateral gray matter (spinal chord)
3) 2nd neuron Decussates at anterior white commissure and ascends contralaterally
4) 2nd neuron synpases in VPL of thalamus and 3rd order neuron goes to sensory cortex. |
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Term
| Describe the course of the lateral corticospinal tract (cortex to chord). |
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Definition
1) UMN cell body in cortex descends ipsilaterally through internal capsule , decussates at caudal medulla (pyramidal ducussation) and descends contralaterally to synapse on cell bodies of the anterior horn of the spinal chord
2) LMN leaves spinal cord and synapses in NMJ. |
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Term
| Where do the neurons of the dorsal columns, spinothalamic tract and lateral corticospinal tracts Decussate? |
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Definition
Dorsal columns and Spinothalamic tracts meet in the medial lemniscus/VPL of thalamus!
1) Dorsal columns
- 2nd order neuron crosses in in medulla (from fasciulus gracilus/cuneatus to the medial lemniscus)
2) Spinothalamic
- 2nd order neuron decussates from spinal chord gray matter to the anterior white matter commisure
3) Primary descending UMN crosses at pyramidal decussation in caudal medulla, before synapsing in anterior horn. |
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Term
Differentiate between UMN and LMN lesion signs in terms of each of the following.
1) Weakness
2) Atrophy
3) Fasciculation
4) Reflexes
5) Tone
6) Babinski
7) Spastic paralysis
8) Clasp knife spasticity |
|
Definition
LMN= everything LOW (less muscle mass, tone, reflexes and down-going toes)
UMN= everything UP (tone DTRs, toes)1)
1) Both have weakness
2) LMN only
3) LMN only
4) UMN + and LMN -
5) UMN + and LMN -
6) UMN +
7) UMN only
8) UMN only |
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Term
What spinal cord lesions and associated symptoms are seen in each of the following?
1) Tabes dorsalis (tertiary syphillus)
2) Syringomyelia
3) MS
4) ALS |
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Definition
1) Degeneration of dorsal roots and dorsal columns
- Impaired proprioception and locomotor ataxia
2) Damaged anterior white commissure of spinothalamic tract
- Bilateral loss of pain/temp (C8-T1)
- Seen with Chiari types 1 and 2
3) Mostly white matter of cervical region; random and asymmetric lesions
- Scanning speech, intention tremor and nystagmus are common
4) Combined UMN and LMN deficits with NO SENSORY DEFICIT (lateral corticospinal tracts and anterior horns affected) |
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Term
What spinal cord lesions and associated symptoms are seen in each of the following?
1) Poliomyelitis and Werdnig Hoffmann disease
2) Vitamin B12 neuropathy
3) ASA occlusion
4) Friedreich's ataxia |
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Definition
1) LMN only due to destruction of anterior horn's
- Flacid paralysis
2) Subacute combined degeneration- demyelination of dorsal columns, lateral corticospinal tract and spinocerebellar
- Ataxic gait, hyporeflexia, impaired position and vibration sense.
3) Spares dorsal columns and tract of lissauer; upper thoracic ASA territory is watershed area, as artery of Adamkiewicz supplies ASA below T8
4) Same as B12 or Vitamin E deficiency
- just left with pain/temp! |
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Term
Patient presents with fever, headache, malaise, nausea, abdominal pain and a sore throat.
On PE, they have muscle weakness and atrophy, with fasciculations and hyporeflexia.
Spinal tap reveals lymphocytic pleocytois with slight protein elevation, but no change in glucose.
A virus is recovered from the stool.
What is the pathogenesis of this condition? |
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Definition
Poliomyelitis from fecal-oral poliovirus (enteric picornavirus- ssRNA +, non-enveloped).
**fetal version of same symptoms would be Werdnig -Hoffman disease**
- Virus replicates in oropharynx and small intestine, before spreading hematogenously to the CNS, where ist destroy anterior horn cells, leading to LMN destruction. |
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Term
| What condition produces a "floppy baby" with tongue fasciculations that dies before 1 year of age? |
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Definition
Werdnig-Hoffman disease- Anterior horn degeneration (LMN only).
AR inheritance (also called infantile spinal muscular atrophy)
**Similar to poliomyelitis** pg 451 FA12 |
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Term
| What condition that is often caused by defect in SOD-1 causes LMN and UMN symptoms, but without sensory, cognitive or oculomotor deficits? How would you treat? |
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Definition
ALS (Lou Gehrig's and Stephen Hawking)
- Presents as fasciculations and atrophy; progressive and fatal
- Riluzole modestly lengthens survival by decreasing pre-synaptic glutamate release
pg 452 FA12 |
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Term
| Describe the pattern of degeneration in Tabes dorsalis (tertiary syphilis). |
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Definition
Look for "prostitute pupils," which accommodate but do not react.
Degeneration of dorsal columns and dorsal roots resulting in impaired proprioception and locomotor ataxia.
- Charcot's joints (bone resorption, and eventual deformity)
- shooting (lightning) pain
- Argyll Robertson pupils
- absent DTRs
- positive Romberg (dorsal columns) and sensory ataxia at night. |
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Term
Which of the following is NOT seen in tertiary syphilis?
1) Positive romberg test
2) Sensory ataxia at night
3) Hyperreflexia
4) Bone resorption/disfiguration of weight bearing limbs
5) Pupils reactive to to accommodation, but not light |
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Definition
3- It should be hypOreflexive for Tabes Dorsalis, due to dorsal column and dorsal root degeneration.
1) Romberg is due to dorsal column
2) Sensory ataxia is proprioception
4) Charcot's neuropathic joints
5) Argyll Robertson pupils (Prostitute pupils) |
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Term
Child present with kyphoscliosis. You learn that he has been staggering and frequently falling
On PE, you note nystagmus, dysarthria and hammer toes.
There is a positive family h/x (although scattered) of similar symptoms.
What is the cause and cause of death in this condition? |
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Definition
Family h/x with gait/ataxia = Friedreich's ataxia
1) AR trinucleotide repeat disorder (GAA) in Frataxin gene produces mitochondrial impairment.
2) Hypertrophic cardiomyopathy most common |
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Term
| What is Brown-Sequard syndrome? What are the major findings? |
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Definition
Hemisection of spinal cord.
** IF you hit above T1, you get horner's**
1) Ipsilateral UMN signs (corticospinal tract) below lesion
2) Ipsilateral loss of tactile, vibration, prioprioception (dorsal column) below lesion.
3) Contralateral pain and temp loss (spinothalamic, which has already crossed)
4) Ipsilateral loss of sensation at level of lesion
5) LMN signs (flaccid paralysis) at level of lesion (hit second order spinal nerves exiting lateral corticospinal tract. |
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Term
| What is Horner's syndrome and why do you see each of the presenting signs? |
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Definition
Sympathectomy of face due to lesion of cord above T1 (Pancoast tumor, Brown-Sequard, late-stage syringomyelia)
PAM is horny (Horner's)
1) Ptosis- drooping eyelid: superior tarsal muscle)
2) Anhydrosis- absense of sweating and flushing (rubor)
on affected side
3) Myosis- pupil constriction
3-neuron oculosympathetic pathway:
- projects from hypothalamus to intermediolateral column of spinal cord (synapsing in lateral horn).
- then to the superior cervical (sympathetic) ganglion.
- Finally to the pupil (opthalmic division of CN V), sweat glands and superior tarsal muscle |
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Term
| Describe the basic 3-neuron arc that is disrupted in Horner's syndrome. |
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Definition
PAM is horney (Ptosis, Anhydrosis, Myosis)
1) Neuron 1 projects from hypothalamus to intermediolateral column of spinal cord (synapsing in lateral horn).
- Hypothalamic lesion
2) Neuron 2 projects to superior cervical (sympathetic) ganglion.
- Pancoast tumor of lung
3) Neuron 3 projects to the pupil (opthalmic division of CN V), sweat glands and superior tarsal muscle (eye-lid raising)
- tumor in the cavernous sinus or a carotid artery dissection |
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Term
What spinal nerve covers each of the following dermatomes?
1) Nipple
2) Low collar shift
3) High, turtleneck shirt
4) Kneecaps
5) Inguinal ligament |
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Definition
1) T4 (teat pore)
2) C4
3) C3
4) L4 (down on all 4's)
5) L1 is IL (Inguinal Ligament) |
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Term
What spinal nerve covers each of the following dermatomes?
1) Posterior half of skull "cap"
2) At umbilicus (appendicitis pain)
3) High, turtleneck shirt
4) Kneecaps
5) Inguinal ligament
6) Erection and sensation of penile and anal zones |
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Definition
1) C2
2) T10 (at belly butTEN)
3) C4
4) L4 (on all 4's)
5) L1 (is IL)
6) S2-4 (keeps penis off the floor) |
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Term
| Where do you feel diaphragm and gallbladder pain? |
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Definition
Right shoulder via phrenic nerve (C3-C5)
C3- high-collar shirt
C4- low collar shirt |
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Term
What spinal nerve level is associated with each of the following reflexes?
1) Achilles
2) Patella
3) Babinski
4) Triceps
5) Biceps |
|
Definition
Count up in order
Babinksi is UMN lesion sign that is normal in 1st year of life
1) Achilles- S1, 2
2) Patella- L3,4
3) Triceps- C7,8
4) Biceps - C5,6 |
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Term
Which primitive reflex is described by each of the following?
1) "hang on for life" with abduct/extend limbs when startled and then draw together
2) Movement of head toward one side if cheek or mouth is stroked (nipple seeking)
3) Sucking response when roof of mouth is touched
4) Curling of fingers/toes if palms of hands/feet are stroked
5) Dorsiflexion of large toe and fanning of others with plantar stimulation
6) Stroking along one side of spine while newborn is in ventral suspension (face down) causes lateral flexion of lower body toward stimulated side |
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Definition
Gone by 1 year and can reappear with frontal lobe lesion!
1) Moro
2) Rooting
3) Suckling
4) Palmar and plantar
5) Babinski
6) Gallant |
|
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Term
Which cranial nerve location is described by each of the following?
1) Lateral to medullary pyramids in medulla
2) At the level of the ponto-medullary junction
3) lateral pons
4) Ponto-midbrain junction
5) Midbrain |
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Definition
CNs that lie medially: III, VI, XII- 3 (x2)= 6 (x2)= 12
1) Hypoglossal (XII)
2) (Medial to lateral): VI, VII, VIII, IX, X
3) V
4) III and IV (inferolateral to III)
5) II and I |
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Term
Where are each of the following located and what is there general function?
1) Pineal gland
2) Superior colliculi
3) Inferior colliculi |
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Definition
Your eyes are above your ears and the SC is above the IC
1) Melatonin secretion, circadian rhythms
- Superior to SC
2) Conjugate vertical gaze center
- Lesion called Parinaud syndrome (pineoloma)
3) Auditory |
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Term
| Might you a patient present with paralysis of conjugate vertical gaze? |
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Definition
| "Setting sun sign" of Pinealoma that lesions the superior colliculus. |
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Term
| Which cranial nerves are sensory, motor or both? |
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Definition
1) Sensory: I, II, VIII
2) Motor: III, IV, VI, XI, XII
3) Both: V, VII, IX, X |
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Term
Which cranial nerve achieves each of the following functions?
1) Motor to stapedius muscle of ear
2) Styolopharygeus muscle
3) Aortic arch chemo and baroreceptors
4) Carotid body and sinus chemo and baroreceptors
5) Salivation
6) Eyelid closing
7) Taste on posterior 1/3 of tongue
8) Cough |
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Definition
1) VII
2) IX- elevated pharynx and larynx
3) X
4) IX
5) VII (sublingual and submandibular glands)
6) VII (orbicularis oculi)
7) IX
8) X |
|
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Term
| Which cranial nerve nuclei are found in the midbrain, pons and medulla, respectively? |
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Definition
XI is in spinal cord, itself!
Medial nuclei= Motor (basal plate)
- Sulcus limitans-
Lateral nuclei= Sensory (alar plate)
1) Midbrain- I, II
2) Pons- III, IV, V, IV, VII, VIII
3) Medulla- IX, X, XII |
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Term
What is the afferent and efferent neuron responsible for each reflex noted below?
1) Corneal
2) Lacrimation
3) Jaw jerk
4) Pupillary
5) Gag |
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Definition
1) In: V1 (nasociliary branch)
Out:VII (temporal branch: orbicularis oculli)
2) In: V1 (loss does not preclude emotional tears)
Out: VII
3) In: V3 (sensory- muscle spindle from masseter)
Out: V3 (motor-masseter)
4) In: II
Out: III (constriction)
5) In: IX
Out: IX, X |
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Term
| Describe the pupillary light reflex. |
|
Definition
1) Neuron 1: photo-sensitive ganglion cells respond and are carried by optic nerve to pre-tectic area (bypasses LGN and cortex)
2) Neuron 2: from pre-tectal runs to the Edinger-Westphal nucleus, whose axons run along both the left and right oculomotor nerves.
3) Neuron 3: Parasympathetic neurons from the oculomotor nerve synapse on ciliary ganglion neurons.
4) Short ciliary nerves leave the ciliary ganglion to innervate the constrictor muscle of the iris. |
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Term
| What are the 3 major vagal nuclei and their functions? |
|
Definition
1) Nucleus Solitarius- Visceral SENSORY information (taste, baroreceptors, gut distention)
- VII, IX, X
2) Nucleus aMbiguous- Motor innervation of pharynx, larynx and upper esophagus (swallowing and palatal elevation)
- IX, X, XI
3) Dorsal motor nucleus- Sends autonomic (parasympathetic) fibers to heart, lungs and upper GI |
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Term
| Which cranial nerves and vessels exit the skull in the Cribriform plate, Middle cranial fossa and Posterior cranial fossa, respectively? |
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Definition
1) Cribriform plate: CN I
2) Middle cranial fossa- through sphenoid bone
- Optic canal: II
- Superior orbital fissure: III, IV, V1, VI
- Foramen Rotundum: V2
- Foramen Ovale: V3
- Foramen Spinosum: Middle meningeal artery
3) Posterior cranial fossa
- Internal auditory meatus: VII, VIII
- Jugular foramen: IX, X, XI, jugular vein
- Hypoglossal canal: XII
- Foramen magnum: XI, brain stem and vertebral arteries |
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|
Term
Which arteries/nerves exit through each of the following?
1) Foramen spinosum
2) Foramen ovale
3) Foramen magnum
4) Jugular foramen
5) Internal auditory meatus
6) Superior orbital fossa
7) Foramen rotundum
8) Cribriform plate |
|
Definition
1) Middle meningeal artery (from maxillary)
2) V3
3) XI, brainstem, vertebral arteries
4) IX, X, XI, jugular vein
5) VII, VIII
6) III, IV, V1, VI
7) V2
8) I |
|
|
Term
| Where do each of the divisions of CN V exit the skull? |
|
Definition
Standing Room Only
1) Superior orbital fossa (V1, along with III, IV, and VI)
2) Foramen Rotundum (V2)
3) Foramen Ovale (V3) |
|
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Term
| What structures can be found in the cavernous sinus and how do they relate to the clinical manifestations of cavernous sinus syndrome? |
|
Definition
Collection of venous sinuses on either side of the pituitary: drains blood from eye and superficial cortex to the internal jugular veins.
- CN III, IV, V1, V2, VI and post-ganglionic sympathetic fibers en route to the orbit
- portion of internal carotid artery
CSS (mass effect): opthalmoplegia, ophthalmic and maxillary sensory loss |
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Term
What cranial nerve lesion produces each of the following?
1) Tongue deviating to the right
2) Jaw deviates to the right
3) Uvula deviates to left
4) Weakness in turning head to left
5) Shoulder droop on right |
|
Definition
1) Right (LMN) CN XII lesion (ipsilateral)
2) Right V motor lesion (unopposed left pterygoid muscle)
3) Right X lesion (weak side collapses and uvula points away
4) Right XI lesion (SCM)
5) Right XI lesion (trapezius) |
|
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Term
| Describe the Rinne/Weber results of conductive and sensorineural hearing loss. |
|
Definition
1) Sensorineural
- Weber lateralizes to good ear
- Rinne: air > bone
2) Conductive
- Weber lateralizes to bad ear
- Bone > air |
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Term
| How might you get paralysis of the upper and upper + lower face, respectively? |
|
Definition
1) UMN lesion (motor cortex to VII nucleus in pons)
- Contralateral lower face paralysis
- Upper face receives bilateral innervation
2) LMN lesion
- Ipsilateral upper and lower facial paralysis
**Complete destruction of VII nucleus itself (Bell's palsy), gives peripheral lesion with inability to close eyelid on that side (orbicularis oculi)** |
|
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Term
| What are the common causes of Bell's palsy? |
|
Definition
Ipsilateral complete facial paralysis and absent eyelid closure due to lesion of facial nucleus or efferent fibers.
ALexander graHam BELL with STD
- AIDS
- Lime's disease
- Herpes simplex
- Sarcoidosis
- Tumors
- Diabetes
FA12 459 |
|
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Term
| What are the muscles of mastication and their innervation? |
|
Definition
3 muscles close: all innervated by V3 (exit foramen ovale)
1) Masseter
2) teMporalis
3) Medial pterygoid
1 muscle opens
1) Lateral pterygoid |
|
|
Term
Describe the basic anatomical organization of the eye.
What region accomplishes each of the following functions?
1) Focuses light (like lens)
2) Controlling the amount of light reaching the back of the eye (like diaphragm)
3) Fine focusing of light for accommodation
4) Converts optical images into electronic signals
5) Holds lens in place and produces aqueous humor
6) Contains only cones, no rods |
|
Definition
Light hits cornea, passes through pupil (controlled by iris) and then focused again by lens, before entering the retina and being processed by the rods and foveal cones.
1) Cornea
2) Pupil- controlled by iris contraction
3) Lens
4) Retina
5) Ciliary body
6) Fovea (acute sight) |
|
|
Term
Which type of eye pathology is described by each of the following?
1) Retinal necrosis + edema producing an atrophic scar
2) Systemic inflammation of the eye
3) Ciliary muscle contraction
4) Ciliary muscle relaxes
5) Sclerosis with decreased elasticity with loss of near vision
6) Acute, painless monocular loss of vision with pale retina and cherry red macula |
|
Definition
1) Retinitis- necrosis and fluid make scar
2) Iritis
3) Near vision: relaxes zonula fibers, relaxing lens and making it convex.
4) Far vision: flattens lens, making it concave
5) Normal aging (Presbyopia because lens cannot become convex)
6) Retinal artery occlusion
- Macula is cherry red because it is much thinner than surrounding tissue, so you can actually see the choroid. |
|
|
Term
True or False:
Older people normally develop presbyopia |
|
Definition
| True- this is loss of near vision due to sclerosis and lost elasticity of the eye, preventing normal lens relaxation (e.g. it cannot become convex for near vision) |
|
|
Term
| Describe how aqueous humor is produced and utilized. |
|
Definition
AH maintains intraocular pressure and provides nutrients to avascular areas of eye (secreted into the anterior and posterior chambers of the eye, between the lens and the cornea).
**disrupted in glaucoma**
1) Secreted into posterior chamber from ciliary body epithelium
2) Travels into anterior chamber, into trabecular meshwork which absorbs it into Schlemm's canal
3) Canal takes aqueous humor from the anterior chamber and delivers it into the bloodstream via the anterior ciliary veins
4) Drained by to posterior chamber and eventually out again. |
|
|
Term
| What is the pathophysiological basis of Glaucoma? |
|
Definition
Impaired flow of aqueous humor leading to increased intraocular pressure...optic disk atrophy causes cupping.
1) Open/wide angle: obstructed outflow (canal of Schlemm); associated with myopia, increased age and AA race (usually "silent" and painless")
2) Closed/narrow angle: Obstruction of flow between iris and lens, causing increased pressure behind iris (very painful, impaired vision and produces "rock hard" eye and frontal headache.
- EMERGENCY, and do NOT give Epi |
|
|
Term
| What are cataracts? What are the major risk factors? |
|
Definition
Painless, bilateral opacification of lens leading to impaired vision.
- Age, smoking, EtOH, sunlight, galactosemia, galactokinase deficiency, diabetes (sorbital), trauma, infection, steroids |
|
|
Term
Which of the following is NOT known to increase the risk of cataracts?
1) Steroids
2) Galactokinase deficiency
3) Galactosemia
4) Diabetes
5) Race |
|
Definition
5- More important for glaucoma (increased ICP, where AA get it more)
Painless, bilateral opacification of lens with vision loss. |
|
|
Term
Patient presents with visual changes.
On fundoscopic exam, you note an elevated optic disk with blurred margins and bigger blind spot than previously was documented.
What happened? |
|
Definition
| Papilloedema from increased ICP (hydrocephalus) |
|
|
Term
| What are the extraocular muscles and their innervation/movements? What would damage to each cranial nerve cause? |
|
Definition
LR6-SO4-AR3
1) Lateral rectus (VI)= laterally direct eye
2) Superior oblique (IV)= down and in while adducted
3) Medial rectus (III)= look medial
Inferior oblique (III)= look up and out while abducted
Superior rectus (III)= look up
Inferior rectus= look down
Damage III- eye looks down and out; ptosis, pupillary dilation and loss of accomodation
Damage IV- Eye drifts upward causing vertical diplopia (can't go down stairs or read newspaper)
Damage VI- Eye directed medially |
|
|
Term
| How can you diagnose cranial nerve lesions by looking at extraocular movements? |
|
Definition
1) Damage III: MR, SR, IF, IO
- eye looks down and out; ptosis, pupillary dilation and loss of accomodation
2) Damage IV- SO
- Eye drifts upward causing vertical diplopia (can't go down stairs or read newspaper)
3) Damage VI- LR
= Eye directed medially |
|
|
Term
| What eye motion tests each of the extra-ocular muscle's function? |
|
Definition
1) IO (III): Up and towards nose
2) SO (IV): Down and towards nose
3) LR (VI): away from nose
4) MR (III): towards nose
5) SR (III): Up and away from nose
6) IR (III): Down and away from nose) |
|
|
Term
| Describe how pupillary constriction/dilation is regulated. |
|
Definition
1) Constriction (miosis)
- Pupillary sphincter muscle (circular muscle), Parasympathetic
- innervation by CN III via the EW nucleus, which synapses on the ciliary ganglion.
2) Dilation (myDriasis)
- Radial muscle (pupillary dilator muscle), sympathetic
- Innervation by T1 pre-ganglionic sympathetic, which travels to superior cervical ganglion and gives post-ganglionic sympathetic fiber via long ciliary nerve.
**This is what is lost in horner's syndrome** |
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Term
| Describe the basic organization underlying the consensual pupillary reflex. How might you lose just a consensual response in the right eye? |
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Definition
1) Light enters retina, which sends signal via CN II to pre-tectal nuclei in midbrain
2) Pre-tectal nuclei activate bilateral EW nuclei, which activate ciliary ganglion parasympathetics, and pupils contract bilaterally (consensual reflex)
**Damage right ciliary ganglion** |
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Term
CN III has both parasympathetic output and motor output to extra-ocular muslces.
What are the common causes of damage to either/both functions? |
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Definition
In cross section, ocular muscle outputs are central and parasympathetic ouputs are peripheral.
1) extra-ocular muscles
- Damage to interior by vascular disease (diabetes: glucose-sorbitol)
- "Down and Out" gaze
2) Parasympathetics (pupillary constriction)
- Compression from PCOM berry aneurysm or uncal herniation (blown pupil). |
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Term
| What is retinal detachment and how is it usually caused? |
|
Definition
Separation of neurosensory layer of retina from pigment epithelium, leading to degeneration of photoreceptors and vision loss.
Often secondary to trauma or diabetic retinopathy (osmotic damage) |
|
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Term
| What is the difference between "wet" and "dry" age-related macular degeneration? |
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Definition
Degeneration of macula causes central vision loss (Scotoma)
1) Dry- slow and due to fat deposits
2) Wet- rapid and due to neovascularization |
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Term
What lesion can cause each of the following visual field defects?
1) Right anopia
2) Bitemporal hemianopia
3) Central scotoma
4) Left hemianoipia with macular sparing
5) Left lower quadrantic anopia
6) Left upper quadrantic anopia
7) Left homonymous hemianopia |
|
Definition
1) Right optic nerve
2) Optic chiasm
3) Macular degeneration (wet or dry)
4) Right PCA lesion (sparing from bilateral circulation)
5) Right dorsal optic radiation (to parietal for lower eye)
6) Right meyer's loop (to temporal for upper eye)
7) Right optic tract (after chiasm) |
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Term
| What is Meyer's loop and the Dorsal optic radiation? Why are they important in diagnosing visual field defects? |
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Definition
Two divisions from optic tract that leaves optic chiasm (left tract has information for right side of visual field)
1) Meyer's loop carries information for the upper visual field to the temporal lobe
- Loss of right Meyer's loop will cause left upper quadrantic anopia (right temporal lesion)
2) Dorsal optic radiation carries information for the lower visual field to the parietal lobe
- Loss of left DOR gives right lower (parietal) quadrantic hemianopia |
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Term
| Describe the pathophysiological basis of internuclear opthlamoplegia |
|
Definition
INO is also called "MLF syndrome" and often seen in MS
1) Lesion of left MLF prevents information from left VI nucleus to be carried to right III nucleus
- When looking to the left, the right eye would look forward because of impaired adduction.
2) Normal abducting eye exhibits nystagmus (in this case it would be right-beating nystagmus.
FA12 pg 464 |
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Term
| What are the classic histological findings of Alzheimer's disease? |
|
Definition
Widespread cortical atrophy with loss of ACh (nucleus of meinhart)
1) Senile plaques: extracellular b-amyloid core- may cause amyloid angiopathy and intracranial hemorrhage (synthesized by cleavage of APP)
2) Neurofibrillary tangles: intracellular abnormally phosphorylated tau protein producing insoluble elements
- Tangles correlate with degree of dementia. |
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Term
True or False:
The degree of dementia in Alzheimer's disease correlated with the amount of extracellular senile plaques. |
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Definition
| False: correlates with intraceullar tau tangles. |
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Term
| What genes are associated with early and late-onset familial alzheimer's disease? |
|
Definition
Familial forms account for 10% of cases
1) Early onset; APP (21), presenilin-1 (14) and presenilin-2 (1)
2) Late onset: ApoE4 (19)
**ApoE2 (19) is protective!** |
|
|
Term
Which of the following genes can be protective in familial alzheimer's disease?
1) ApoE4 (19)
2) ApoE2 (19)
3) APP (21)
4) Presenilin 1 (14)
5) Presenilin 2 (1) |
|
Definition
2
All others are detrimental
- Presenilin 1/2 and APP are juvenile-onset
- ApoE4 is adult-onset |
|
|
Term
True or False:
Kids with down syndrome have a greater chance of getting alzheimer's disease later in life. |
|
Definition
True!
Extra copy of APP (chromosome 21) may have greater processing to a-beta plaques. |
|
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Term
What causes of dementia are associated with each of the following?
1) Intracellular, aggregated tau protein with frontotemporal atrophy
2) Intracellular, abnormally phosphorylated tau
3) alpha-syn nuclein deficit
4) Spongiform cortex |
|
Definition
Can also be caused by multi-infarcts (2nd most common cause in elderly, behind AD), syphilis, HIV, vitamin B12 deficiency, Wilson's and normal pressure hydrocephalus.
1) Pick's disease (FTD): Dementia, aphasia, parkinsonian aspects; personality changes
- Spares parietal lobe and posterior 2/3 of superior temporal gyrus.
2) Alzheimer's disease
- 90% sporadic in elderly (Trisomy 21 association)
- 10% familial (juvenile or adult-onset)
3) Lewy body dementia
- Parkinsonism with dementia and hallcuinations
4) Creutzfeldt-Jakob disease (CJD)
- Prions (PrPc converted to PrPsc sheets that are resistant to proteases)
- Rapidly progressive demential (weeks to months) with myoclonus |
|
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Term
What causes of dementia are associated with each of the following?
1) Dementia, aphasia, parkinsonian aspects; personality changes, sparing parietal lobe and posterior 2/3 of superior temporal gyrus.
2) Most common cause of dementia in elderly
3) Parkinsonism with dementia and hallcuinations
4) Rapidly progressive demential (weeks to months) with myoclonus |
|
Definition
1) Pick's disease (FTD): Intracellular tau tangles and FT atrophy
2) Alzheimer's disease
3) Lewy body dementia- alpha syn-nuclein deficit
4) Creutzfeldt-Jakob disease (CJD)
- Prions (PrPc converted to PrPsc sheets that are resistant to proteases) |
|
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Term
| What is the classic "Charcot's triad" and what disease is it found in? |
|
Definition
Don't confuse with charcot's joints in Tabes dorsalis.
MS is SIN
Relapsing and remitting disease of young (20-30) white women
1) Scanning speech ("Walk (pause) ing is good ex (pause) er (pause) cise")
2) Intention tremor, Incontinence, Internuclear opthalmoplegia (MLF syndrome)
3) Nystagmus |
|
|
Term
| What are the classic laboratory findings associated with MS? |
|
Definition
Relapsing and remitting autoimmune inflammation and demyelination of CNS in young white women (20-30)
1) Increased protein (IgG) in CSF)
- Oligoclonal bands are diagnostic
2) MRI (GOLD standard)
- Periventricular plaques (oligodendrocyte loss and reactive gliosis with destruction of axons) |
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Term
| How do you treat a young women with evidence of periventricular plaques on T2-weighted MRI and elevated IgG levels in her CSF? |
|
Definition
MS- relapsing and remitting autoimmune inflammation and demyelination.
1) Beta-IFN
2) Immunosuppression- steroids
3) Natalizumab- alpha-4 integrin antibody (prevents inflammatory cell attachment)
- Tysabri is other name- watch out for PML (used only in relapsed cases of MS)
4) Symp. treatment of neurogenic bladder (catheterization, mACh agonists), spasticity (baclofen, GABA receptor agonist), pain (opioids) |
|
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Term
| How does Guillain-Barre syndrome (acute inflammatory demyelinating polyradiculopathy) differ from MS? |
|
Definition
Both are autoimmune attack of myelin
1) GBS (molecular mimicry of C. jejuni or herpesvirus)
- hits peripheral nerves (Schwann cells), causing symmetrical ascending muscle weakness beginning in distal lower extremities.
- May cause facial paralysis and autonomic (heart and respiratory) issues.
- Most people recover in weeks to months.
2) MS hits central nervous system with periventricular plaques, damaging axons and oligodendroglia wrapping them. |
|
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Term
| How do the treatments for MS and Guillain-Barre syndrome differ? |
|
Definition
1) MS is central
- IFN-b, Natalizumab (tysabri), steroids, symptomatic (baclofen, mACh antagonist)
2) GBS is peripheral and post-infectious (C. jejuni or Herpes molecular mimicry autoimmune reaction)
- Respiratory support
- Plasmapheresis, IV IG. |
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Term
| What are the CSF findings in MS and Guillain-Barre? |
|
Definition
1) MS- Scanning speech, INO, intention tremor, urinary incontinence, nystagmus
- Increased protein (IgG) in CSF
2) GBS- ascending symmetric muscle weakness
- Increased CSF protein with normal cell count (albuminocytologic dissociation) |
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|
Term
Which demyelinating disease is described by each of the following?
1) Demyelination of CNS due to destruction of oligodendrocytes associated with JC virus (2-4% of AIDS patients).
2) Multifocal peri-venular inflammation and demyelination after infection (e.g. chickenpox, measles) or certain vaccinations (rabies, smallpox)
3) AR lysosomal storage disease due to arylsulfatase A deficiency, leading to impaired production of myelin sheath
4) Group of hereditary nerve disorders related to defective production of proteins involved in structure and function of peripheral nerves or myelin sheath.
5) AR lysosomal storage disease associated with absent galactocerebrosidase, leading to destruction of myelin sheath. |
|
Definition
1) PML (also associated with natiluzumab in rare cases)
- Rapidly progressive and usually fatal
2) Acute disseminated (post-infectious) encephalomyelitis
3) Metachromatic leukodystophy
4) Charcot-Marie-Tooth disease- Hereditary motor and sensory neuropathy (HMSN)
5) Krabbe's disease
466 FA12 |
|
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Term
| What are the major kinds of partial and generalized seizures and what distinguishes the 2 groups? |
|
Definition
Partial involves 1 area of brain, usually the medial temporal lobe. Generalized is more diffuse.
1) Partial
- Simple (consciousness intact)- motor, sensory, autonomic, psychic)
- Complex (impaired consciousness)
2) Generalized
- Absence (petit mal, 3Hz, no post-ictal confusion. Blank state)
- Myoclonic- quick, repetitive jerks
- Tonic-clonic (grand mal)- alternating stiff/movement
- Tonic- stiff
- Atonic- "drop seizures" (mistaken for fainting. |
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Term
| What are the most common causes of seizures in childhood, adulthood and elderly, respectively? |
|
Definition
Epilepsy= Recurrent seizure disorder (NOT febrile seizures)
1) Children: Genetic, infection (febrile), trauma, congenital, metabolic
2) Adults: Tumors, trauma, stroke, infection
3) Elderly: Stroke, Tumor, trauma, metabolic, infection. |
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Term
What type of headache is described by each of the following and how do you treat?
1) Unilateral, with repetitive brief headaches characterized by peri-orbital pain and ipsilateral lacrimation, rhinorrhea and Horner's
2) Unilateral; 4-72 h of pulsating pain with nausea, photophobia or phono-phobia +/- preceding aura.
3) Bilateral; >30 minutes of steady pain that is not aggravated with light or noise.
2) |
|
Definition
Headache in irritation of dura, cranial nerves and/or extra-cranial structures, but NOT parenchyma of brain.
1) Cluster- M>W
- Give oxygen and/or Sumatriptan
2) Migraine- Irritation of CN V and release of substance P, CGRP and vasoactive peptides.
3) Tension
- Propranolol, NSAIDs, Sumatriptan for acute cases |
|
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Term
| What is believed to be the pathological basis of migraine headaches? |
|
Definition
unilateral pulsating pain for 4-72 hours with photo/phonosensitivity +/- aura.
- Irritation of CN V and release of substance P, CGRP and vasoactive peptides.
**give Propranolol, NSAIDs and sumatriptan for acute cases** |
|
|
Term
| How can you distinguish between peripheral and central vertigo? |
|
Definition
Vertigo= illusion of movement (NOT just dizziness or lightheadedness)
1) Peripheral (more common)
- Inner ear etiology (semicircular canal debris/benign positional, vestibular nerve infection, Meniere's disease)
- Positional testing reveals delayed horizontal nystagmus.
2) Central
- Brainstem or cerebellar lesion (vestibular nuclei, posterior fossa tumor)
- Positional testing reveals immediate nystagmus in any direction (may change directions). |
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Term
A number of neurocutanous disorders affect patients.
What disorder is described by each of the following and what are the key complications?
1) Port-wine stains (nevus flammens) in V1 distribution. Often seen with ipsilateral leptomeningeal angiomas, pheochromocytomas
2) Hamartomas in CNS and Skin
3) Cafe-au-lait spots and Lisch nodules
4) Cavernous hemangiomas in skin, mucosa and organ. |
|
Definition
1) Sturge-Weber: Congenital disorder
- Glaucoma, seizures, hemiparesis, sporadic mental retardation
2) Tuberous sclerosis- AD
- HAMARTOMAS
- Hamartoma of skin and CNS
- Adenoma sebaceum (cutaneous angiofibroma)
- Mitral regurgitation
- Ash-leaf spots
- cardiac Rhabomyoma
- (Tuberous sclerosis)
- autOsomal dominant
- Mental retardation
- renal Angiomylolipoma
- Seizures
3) NF-1 (von Ricklinghausen's disease)- Autosomal dominant (100% penetrance with variable expression)
- Neurofibromas in skin, optic gliomas and pheochromocytomas
4) VHL disease- AD mutation in tumor suppressor VHL on chromosome 3 (inactivates HIF-1a usually)
- Bilateral renal cell carcinoma
- Hemangioblastoma in retina, brain stem, cerebellum
- Pheochromocytomas |
|
|
Term
| What are the classic features of Tuberous Sclerosis? |
|
Definition
AD disease: HAMARTOMAS
Renal, Cardiac, CNS and Cutaneous manifestations
1) Hamartoma of skin and CNS
2) Adenoma sebaceum (cutaneous angiofibroma)
3) Mitral regurgitation
4) Ash-leaf spots
5) Cardiac Rhabomyoma
6) (Tuberous sclerosis)
7) autOsomal dominant
8) Mental retardation
9) renal Angiomylolipoma
10) Seizures |
|
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Term
| What disease is caused by autosomal dominant mutations in the NF-1 gene on chromosome 17? |
|
Definition
Neurofibromatosis type 1 (associated with pheochromocytoma, optic gliomas and neurofibromas in skin.
See Cafe-au-Lait spots ad Lisch nodules (pigmented iris hamartomas)
- Cutaneous, Adrenal and Optic manifestations. |
|
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Term
| What is the pathophysiological basis of VHL disease? |
|
Definition
Neurocutanous disorder with cavernous hemangiomas in skin, mucosa and organs, and hemangioblastomas in retina, brainstem, cerebellum
AD mutation in VHL (tumor suppressor on chromosome 3).
- VHL normally inhibits HIF-1a from producing aberrant vasculogenesis when hypoxia is not present. |
|
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Term
| What are the most common types and locations of primary brain tumors in adults and kids? |
|
Definition
Adults= Glioblastoma multiforme
Kids= Medulloblastoma
1) Kids= Mostly Infratentorial
Infratentorial: Medulloblastoma, Hemangioblastoma (VHL disease), Ependymoma
Supratentorial: Pilocytic (low-grade) astrocytoma. Craniopharyngioma
2) Adults= mostly supra tentorial
- Infratentorial: Pituitary adenoma, Schwanomma
- Supratentorial: Glioblastoma mutliforme (IV astromcytoma), Meningioma, Oligodendroglioma |
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|
Term
What type of primary brain tumor is described by each of the following?
1) Found in the cerebral hemispheres, often crossing the corpus callosum in a "butterfly" pattern. Positive GFAP staining and grave prognosis (<1 year)
2) Resectable tumor that occurs in convexities of hemispheres and parasagittal region. Tumor exhibits spindle cells that are concentrically arranged in whorled pattern, with psammoma bodies (laminated calcification)
3) S-100 positive, resectible tumor that is often localized to CN-VIII in the cerebellopontine angle.
4) Rare, slow growing tumor found in the frontal lobes, exhibiting a "chicken-wire" capillary pattern on pathology with numerous "fried egg" cells.
5) Often produces hypopituitarism and bitemporal hemianopsia |
|
Definition
ALL adult tumors
1) Glioblastoma multiforme (supratentorial, grade IV astrocytoma)
- Most common primary tumor of adults
- Pleomorphic "Pseudopalisading" tumor cells- border central areas of necrosis and hemorrhage.
2) Meningioma (supratentorial)- 2nd most common primary tumor in adults
- arising from arachnoid cells external to the brain.
3) Schwannoma (infratentorial)- 3rd most common primary tumor of adults
- Often an acoustic schwanomma
4) Oligodendroglioma (supratentorial)
5) Pituitary adenoma (most commonly prolactinoma) |
|
|
Term
| What condition is associated with bilateral schwannoma? |
|
Definition
NF type 2
vs. NF type 1 with optic gliomas, pheochromocytoma and neurofibromas of skin |
|
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Term
What type of primary pediatric brain tumor is described by each of the following?
1) Well circumscribed tumor in posterior fossa that is benign and GFAP positive
2) Highly malignant cerebellar tumor of primitive neuroectodermal origin that often compresses 4th ventricle and causes hydrocephalus
3) Cells form perivascular peudorossettes with rod-shaped blepharopalsts (basal ciliary bodies) found near nuclei. Often compresses 4th ventricle causing hydrocephalus.
4) Cerebellar tumor associated with VHL disease and found in context of retinal angiomas
5) Benign childhood tumors that cause hypopituitarism and bitemporal hemianopsia. |
|
Definition
1) Pilocytic astrocytoma (low-grade)- usually supratentorial
- Rosenthal fibers (eosinophilic, corkscrew fibers)
- Gross appearance is cystic and solid.
2) Medulloblastoma (infratentorial)
- "Homer-write Rosettes"
- Radiosensitive, solid mass (gross) composed of small blue cells (histology)
3) Ependymoma (infratentorial)
- poor prognosis
4) Hemangioblastoma (infratentorial)
- Can produce EPO (secondary polycythemia)
- Foamy cells and high vascularity are characteristic
5) Craniopharyngioma (supratentorial)
- most common cause of primary hypopituitarism in kids.
- Rathke's pouch derivative that is commonly calcified. |
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Term
What primary pediatric tumor is associated with aec of the following pathological findings?
1) Rosenthal fibers (eosinophilic, corkscrew fibers)
- Gross appearance is cystic and solid.
2) "Homer-wright Rosettes"
- Radiosensitive, solid mass (gross) composed of small blue cells (histology)
3) Perivascular peudorossettes with rod-shaped blepharopalsts (basal ciliary bodies) found near nuclei.
4) Foamy cells and high vascularity
5) Rathke's pouch derivative that is commonly calcified. |
|
Definition
1) Pilocytic astromcytoma (low grade supratentorial tumor)
- GFAP + in posterior fossa- well circumscribed and benign
2) Medulloblastoma (infra)
- Highly malignant cerebellar tumor that compresses 4th ventricle
3) Ependymoma (infra)
- Also commonly compress 4th ventricle
4) Hemangioblastoma
- Common in VHL and can produce EPO (secondary polycythemia)
5) Craniopharyngioma
- Commonly calcified
FA12 470 |
|
|
Term
| What are the 4 common herniation syndromes? |
|
Definition
Coma and death occur if brainstem is compressed
1) Cingulate (subfalcine) herniation under falx cerebri
- Can compress anterior cerebral artery (leg hemiparesis)
2) Downward transtentorial (central) herniation
3) Uncal herniation- medial temporal lobe
4) Cerebellar tonsillar herniation into foramen magnum |
|
|
Term
Why do you see each of the following clinical signs during Uncal herniation?
1) Ipsilateral dilated pupil/ptosis
2) Contralateral homonymous hemianopia
3) Ipsilateral paresis
4) Duret hemorrhage- paramedian artery rupture. |
|
Definition
1) Stretching CN III (levator palpebrae)
2) Compression of ipsiltateral posterior cerebral artery
3) Contralateral crus cerebri (Kernohan's notch)
4) Caudal displacement of brainstem |
|
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Term
Patient comes into ER because he can't see anything on his left side, and he is having difficulty feeling his right arm.
On opthalmic exam you see that his right pupil is very large and the eyelid is drooping.
Why are you worried? |
|
Definition
Sounds like Uncal herniation (Right)
1) Contralateral hemianopia because of compression of ipsilateral PCA, which supplies occipital cortex.
2) Ipsilateral blown pupil and ptosis because of CN III compression (levator palpebrae and pupillary constrictor)
3) Ipsilateral paresis because of compression of contralateral crus cerebri by herniating medial temporal lobe |
|
|
Term
| What is the difference between a ring-enhancing lesion, a uniformly enhancing lesion and a heterogeneously enhancing lesion in terms of etiology and prognosis of a given brain lesion? |
|
Definition
1) Ring-enhancing
- Metastasis (lung> breast> kidney> melanoma> GI), Abscesses, Toxoplasmosis, Primary CNS lymphoma (AIDS, EBV)
2) Uniformly enhancing
- Metastatic lymphoma (B cell NHL), meningioma, metastases (usually ring enhancing)
3) Heterogeneously enhancing
- Glioblastoma multiforme |
|
|
Term
What does each of the following glaucoma drugs do?
1) Epinephrine
2) Timolol
3) Acetazolamide
4) Pilocarpine
5) Physiostigmine
6) Latanoprost |
|
Definition
1) alpha agonist (don't use in closed/narrow angle)
- decreases aqueous humor synthesis due to vasoconstriction
- SE: mydriasis and stinging.
2) Beta-blocker
- decrease aqueous humor secretion from ciliary body
- SE: none
3) CA-inhibitor
- Decrease aqueous humor secretion because of decreased HCO3-
- SE: none
4) Direct cholinergic mimetic
- increase outflow of aqueous humor; contract ciliary muscle and open trabecular meshwork (in emergencies to open canal of schlemm)
4) Reversible ACh-E-inhibitor (indirect increase in cholinergic signalling)
- same effect as 4.
- SE: Miosis, cyclospasm
5) PGF2a (prostaglandin)
- Increases aqueous humor outflow.
- SE: darkens color of iris (browning) |
|
|
Term
| Which glaucoma drugs act by decreasing aqueous humor secretion and which drugs act by increasing outflow? |
|
Definition
1) Decrease secretion
- Alpha agonists (Epi and Brimonide)
- Beta blockers (Timolol, betaxolol, carteolol)
- Diuretics (Acetazolamide)
2) Increase outflow
- Cholinomimetics (pilocarpine/direct and physiostigmine/indirect)
- Prostaglandin (latanoprost) |
|
|
Term
| What are the major opioid analgesics and how do they work to suppress pain and to treat acute pulmonary edema? |
|
Definition
Bind opioid receptors (mu= morphine, delta= enkephalin, kappa= dynorphin) to modulate synaptic transmission
- Open K+ channels, close Ca2+ channels......decrease transmission.
- Inhibit release of ACh, NE, 5-HT, glutamate and substance P
1) Morphine
2) Fentanyl
3) Codeine
4) Heroin
5) Methadone (maintenance program for addicts)
6) Meperidine
7) Dextromethorphan (also hits cough)
8) Diphenoxylate (diarrhea also) |
|
|
Term
| What are the major toxicities associated with using opioid analgesics to treat pain and/or pulmonary edema? |
|
Definition
Treat overdose with naloxone or naltrexone (opioid receptor antagonists)
1) Addiction
2) Respiratory depression
3) Constipation
4) Miosis (pinpoint pupils)
5) Additive CNS depression with other drugs |
|
|
Term
True or False
Miosis and constipation associated with opioid use will decrease with prolonged usage due to development of tolerance |
|
Definition
|
|
Term
Which opioid analgesics are used to treat each of the following, in particular?
1) Diarrhea
2) Cough
3) Maintenance for addicts |
|
Definition
Most will hit pain and/or pulmonary edema (respiratory suppression)
1) Loperamide and Diphenoxylate
2) Dextromethorphan
3) Methadone
**Watch out for myosis (pinpoint pupils) and constipation, as well as addiction. |
|
|
Term
| Why might you choose to prescribe Butorphanol in the place a drug like Fentanyl? |
|
Definition
Treats pain without as much respiratory depression (still can cause withdrawal)
It is a partial (vs. full) agonist of opioid mu (morphine) receptors and an agonist of kappa (dynorphin) receptors |
|
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Term
| What weak opioid agonist is used to treat chronic pain and is associated with risk of seizures? |
|
Definition
Tramadol (Tram it all in!)
- Also inhibits 5-HT and NE re-uptake (works on multiple neurotransmitters) |
|
|
Term
There are a great number of epilepsy drugs. What drugs are first line options for the following types of seizures? How does each work?
1) Simple partial
2) Complex partial
3) Tonic-clonic
4) Absense
5) Status (persistent)
6) Myoclonic seizures |
|
Definition
1) Carbamazepine- Increases Na+ channel (also first line for trigeminal neuralgia)
2) Carbamazepine
3) Carbamazepine (Na+ inactivation), Phenytoin (Na+ inactivation) and Valproic acid (Na+ inactivation and increase [GABA]
4) Ethosuximide- Blocks thalamic T-type calcium channels
5) Phenytoin prophylaxis
Benzos for acute treatment (increase GABAa activation)
6) Valproic acid |
|
|
Term
How do each of the following anti-seizure drugs work? When are they used?
1) Phenytoin
2) Carbamazepine
3) Lamotrigine
4) Gabapentin
5) Topiramate
6) Phenobarbital |
|
Definition
Carbamezapine for adults with partial or tonic-clonic, and Phenobarbitol for kids.
1) Increase Na+ inactivation
- 1st line for tonic-clonic seizures
2) Increase Na+ channel inactivation
- 1st line in simple partial, complex partial and tonic-clonic seizures.
- 1st line for trigeminal neuralgia
3) Blocks voltage-gated Na+ channels
- used for simple and complex partial seizures and for tonic-clonic seizures
4) Inhibits HVA Ca2+ channels and acts as GABA analogue
- peripheral neuropathy and bipolar disorder
5) Blocks Na+ channels and increases GABA action
- Same as Gabapentin
6) Increase GABAa action
- 1st line in children with partial or tonic-clonic seizures |
|
|
Term
How do each of the following anti-seizure drugs work? When are they used?
1) Valproic acid
2) Ethosuximide
3) Benzodiazepine
4) Tiagabine
5) Vigabatrin
6) Levetiracetam |
|
Definition
1) Increase Na+ channel inactivation and increase [GABA]
- 1st line in tonic-clonic seizures and myoclonic seizures
2) Blocks thalamic T-type Ca2+ channels
- 1st line in Absense seizure
3) Increase GABAa action
- 1st line for acute treatment of status epilepticus (peristent seizure state)
4) Inhibits GABA reuptake
- Partial seizures
5) Irreversibly inhibits GABA transaminase (increase GABA)
- partial seizures
6) May modulate GABA and glutamate release
- Partial and tonic-clonic seizures. |
|
|
Term
What are the toxicities of each of the following epilepsy drugs?
1) Benzodiazepines
2) Carbamezepine
3) Ethosuximide
4) Phenobarbital |
|
Definition
1) 1st line for Status epilepticus (increase GABAa effects)
- Sedation, toelrance, dependence
2) 1st line for partial, tonic-clonic and trigeminal neuralgia
- Diplopia, ataxia, blood dyscrasia (agranulocytosis, aplastic anemia), liver toxicity, teratogenesis, SIADH, stevens-johnson, induce CYP
3) 1st line for absense seizures
- Fatigue, GI distress, Headache, Rash, steven johnson
4) 1st line for kids with partial and tonic-clonic seizures
- Sedation, tolerance, depdendence, CYP induction |
|
|
Term
What are the toxicities of each of the following epilepsy drugs?
1) Phenytoin
2) Valproic acid
3) Lamotrigine
4) Gabapentin
5) Topiramate |
|
Definition
1) 1st line for tonic-clonic seizures (Na+ channel innactivation)
- Nystagmus, diplopia, ataxia, sedation, gingival hyperplasia, hirsutism, megaloblastic anemia, teratogen, SLE-like, CYP-induction.
2) 1st line for tonic-clonic and myoclonic
- GI, fatal hepatotoxicity (rare), neural tube defects in fetus (spina bifida), tremor, weight gain
3) Blocks voltage gated Na+ channels
- Stevens johnson syndrome
4) Inhibits HVA Ca2+ channels and acts as GABA analogue
- Sedation and ataxia
5) Blocks Na+ channels and increase GABA action
- Sedation, mental dulling, kidney stones, weight loss |
|
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Term
| Which epilepsy drugs should be avoided during pregnancy? |
|
Definition
1) Valproic acid (neural tube- spina bifida)
2) Phenytoin and Carbamazepine- fetal hydantoin syndrome |
|
|
Term
| What is Stevens-Johnson syndrome and what epilepsy drugs are known to produce it? |
|
Definition
Prodrome of malaise and fever followed by rapid onset erythematous/purpuric macules (oral, ocular, genital), which progress to epidermal necrosis and sloughing.
Carbamezapine, Ethosuximide, Lamotrigine |
|
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Term
| What is the clinical utility and mechanism of action of Phenytoin? |
|
Definition
Used for tonic-clonic seizures and as a class 1B anti-arrhythmic (decreased refractory period).
Use-dependent blockage of Na+ channels: decreased refractory period and inhibition of glutamate release from excitatory pre-synaptic terminal.
Decreased folate absorption and Teratogen! |
|
|
Term
| What are the important toxicities of phenytoin? |
|
Definition
1B anti-arrhythmic and for tonic-clonic seizures.
1) Teratogen (fetal hydantoin syndrome)
2) Folic absorption defect (macrocytic anemia)
3) Nystagmus, ataxia and diplopia
4) Sedation
5) SLE-like syndrome
6) Chronic use produces gingival hyperplasia in children
7) Hirsutism. |
|
|
Term
| What is the clinical utility and mechanism of action of Barbiturates? |
|
Definition
Sedative for anxiety, seizures, insomnia and to induce anesthesia (thiopental).
**Phenobarbital is first-line in pediatric seizures**
- Facilitates GABAa action by increasing duration of Cl- channel opening (decreased firing).
** DON'T give in porphyria** |
|
|
Term
| How do you treat an overdose of a bartiburate? |
|
Definition
REALLY RISKY (unlike benzos, which can be reversed with flumenazil)
Assist respiration and get BP up
Barbiturates like phenobarbital can cause CNS depression when combined with alcohol, as well as respiratory depression and cardiovascular depression (leading to death)
- Can also interact with drugs that go by CYP system |
|
|
Term
| How does the mechanism of Phenobarbital differ from Lorazepam? |
|
Definition
Barbiturates like Phenobarbital increase the length of time of Cl- channel opening, thereby facilitating GABAa effects and preventing neural firing.
Benzos like Lorazepman facilitate GABAa action by increasing the frequency (not duration) of Cl- channel opening |
|
|
Term
| What is the clinical utility and mechanism of action of Benzodiazepines? |
|
Definition
1) Use
- anxiety
- status epilepticus (lorazepam and diazepam)
- detoxification (alcohol withdrawal), - night terrors and sleepwalking (decrease REM sleep)
- general anesthesia
- hypnotic (insomnia)
2) Increase frequency of Cl- channel opening, thereby facilitating GABAa action |
|
|
Term
| How are Benzodiazepine overdoses reversed? |
|
Definition
Flumazenil (competitive GABA benzo receptor antagonist)
Less risky than barbiturates, which cannot be reversed. |
|
|
Term
| What are the important non-benzodiazepine hypnotic drugs and how can they be reversed? |
|
Definition
Zolpidem (Ambien), Zaleplon, Eszopiclone
- less amnestic and less risk
Act via BZ1 receptor and reversed by Flumazenil (just like benzos)
- Lower risk and can be used in old people |
|
|
Term
| How does drug solubility influence anesthetic action? |
|
Definition
- Lipid soluble drugs cross BBB easily, and are thus more potent, with lowest MAC.
- Water insoluble drugs produce rapid induction and recovery time
Ex 1) NO2 has low blood and lipid solubility, so it is rapid-acting and not very potent.
Ex2) Halothane has high lipid and blood solubility, so it is long-lasting and potent. |
|
|
Term
| How do anesthetics act in the lungs, blood and brain, respectively? |
|
Definition
1) Lungs
- By increasing the rate and depth of ventilation, you increase GAS TENSION (drug action)
2) Blood
- Increasing blood solubility will make slower onset of action
3) Tissue (brain)
- As AV concentration gradient increases, so does solubility= slower onset and action. |
|
|
Term
| What are the major inhaled anesthetics and how do they work/what are their effects? |
|
Definition
Halothane, Enflurance, Isoflurane, Sevoflurane, NO
- Unknown mechanism
- Myocardial depression, respiratory depression, nausea/emesis, increased CBF (decreased metabolic demand of brain) |
|
|
Term
Which inhaled anesthetic is associated with each of the following side effects?
1) Hepatotoxicity
2) Nephrotoxicity
3) Convulsions
4) Malignant hyperthermia
5) Trapped gas |
|
Definition
1) Halothane
2) Methoxyflurane
3) Enflurane
4) Rare
5) NO |
|
|
Term
| What are the major IV anesthetics and how do they work/what are their effects? |
|
Definition
1) Barbiturates (Thipental)
- High potency/high lipid solubility
- Used for induction or short procedures (rapid distribution and elimination)
- decrease CNS BF
2) Benzodiazepines (Midazolam)
- During Endoscopy as an adjunct to gas and narcotics
- post-operative respiratory depression and hypotension (give flumazenil)
3) Arylcyclohexylamines (Ketamine)
- PCP analog/dissociative anesthetic that blocks NMDA receptors
- CV stimulants that cause disorientation, hallucination and bad dreams
- Increase CBF
4) Opiates (Morphine, fentanyl)
- General anesthesia
5) Propofol
- Rapid anesthesia induction and short procedures
- Less post-operature nausea than thiopental (potentiated GABAa) |
|
|
Term
| Which IV anesthetics can be used for induction anesthesia and/or short procedures? |
|
Definition
Thiopental (barbiturate) and Propofol (GABAa potentiation)
Propofol has less post-operative nausea |
|
|
Term
| What are the major ester and amide local anesthetics and how do they work? |
|
Definition
Used in minor surgery, spinal anesthesia (give amides if allergic to esters)
1) Esters: Procaine, cocaine, tetracaine
2) Amide (2 I's): Lidocaine, Meplivacaine, buplivacaine
- Block activated Na+ channels by binding specific receptors on inner portion of channel
- Amine local anesthetics penetrate membrane in uncharged form and then bind to channel as charged form. |
|
|
Term
| What is the order of nerves that are blockaded in a typical nerve block with lidocaine? |
|
Definition
Pain > temperature > touch > pressure
1) Small diameter> large diameter (Most important)
2) Myelinated > unmyelinated
Small myelinated > small un-myelinated> large myelinated> large un-myelinated |
|
|
Term
| Why are local anesthetics (except cocaine) generally given along with Epinephrine? |
|
Definition
To enhance local action
- Decrease bleeding
- Increase anesthesia
- Reduce systemic concentration |
|
|
Term
| Why are higher concentrations of procaine needed to reach infected tissue? |
|
Definition
| In acidic environment, alkaline anesthetics are charged and cannot penetrate membranes |
|
|
Term
| What are the major available depolarizing and non-depolarizing NM blocking drugs? How can they be reversed? |
|
Definition
Used for muscle paralysis in surgery or mechanical ventilation: Selective for motor (vs. autonomic) nAChR
1) Depolarizing: Succinylcholine
- complications include hypercalcemia and hyperkalemia
- Phase 1 (prolonged depolarization)- no antidote and AChE-i will make things worse
- Phase 2 (repolarized but blocked)- Can reverse with neostigmine
2) Non-depolarizing: Competitive for AChR (tubocuranine and all the "uriums")
- Reverse with neostigmine, edrophonium and other cholinesterase inhibitors. |
|
|
Term
| What is the drug of choice for malignant hypertension and how does it work? |
|
Definition
Dantrolene: prevents release of Ca2+ from SR of skeletal muscle
Remember, malignant HTN is caused by inhaled anesthetics (except N2O) and succinocholine (depolarizing NM blocker)
**Also used for neuroleptic malignant syndrome (toxicity of antipsychotics)** |
|
|
Term
| What are the major drugs used for Parkinson's and how do they work? |
|
Definition
PD due to loss of dopamine and excess ACh
BALSA
1) Bromocriptine (ergot)- dopamine analog
2) Amantadine- increase dopamine release
3) Levodopa (with carbidopa)
4) Selegiline (and COMT inhibitors)- prevent L-Dopa degredation
5) Antimuscarinics (Benztropine) |
|
|
Term
| What is the treatment of choice for essential and/or familial tremors? |
|
Definition
| Beta blocker (propranolol) |
|
|
Term
Why might you give Selegiline to a patient with Parkinson's?
What about Entacapone? |
|
Definition
MAO type B inhibitor (metabolizes dopamine over NE and 5-HT) used as adjunct to L-dopa, to prevent dopamine breakdown.
Entacapone is a COMT inhibitor, and is used for the same reason. |
|
|
Term
| What anti-viral agent (influenza A) that is known to produce ataxia is also used to treat Parkinson's |
|
Definition
| Amantadine- increase dopamine release |
|
|
Term
| Why is Carbidopa given with L-DOPA to treat Parkinson's? |
|
Definition
| Peripheral Dopa decarboxylase inhibitor that prevents conversion to dopamine in periphery, which might cause cardiac arrhythmia. |
|
|
Term
| Why use Benztropine in Parkinson's? |
|
Definition
Curb the excess ACh- Park your Mercedes Benz
- Anti-muscarinic that improves tremor and rigidity, but not bradykinesia. |
|
|
Term
| What kinds of drugs are given to treat Alzheimer's disease and how do they work? |
|
Definition
1) NDMA receptor antagonist (Memantine)
- prevents Ca-mediated excitotoxicity
- Can cause dizziness, confusion and hallucinations
2) Cholinesterase inhibitors (Donepezil, Galantamine, Rivastigmine)
- Can cause nasuea, dizziness and insomnia |
|
|
Term
| What is the therapeutic strategy in Huntington's disease and how do each of the drugs work? |
|
Definition
Disease state= Too much dopamine and too little GABA and ACh (opposite of PD)
1) Reserpine + Tetrabenazine- amine depleting (dopamine)
2) Haloperidol- Dopamine receptor antagonist |
|
|
Term
What drug is used to treat acute migraines and cluster headache attacks?
How does it work and what are the associated toxicities? |
|
Definition
Sumatriptan (A SUMo wrestler TRIPs ANd falls on your head)
- 5-HT 1b/1d agonist that causes vasoconstriction and inhibits CN V activation and vasoactive peptide release (half live <2h)
2) Conorary vasospasm (don't give in patients with CAD or Prinzmetal's angina). |
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