Neurology

Question 1

In hemi-intention syndrome, where is the lesion?

Answer 1

Lesion contralateral to neglected side (i.e., neglect left, lesion on right)

Question 2

A patient circles to both left and right side. Where is the lesion?
A) Cerebrum
B) Thalamus
C) Hypothalamus

Answer 2

B and C (Diencephalon)

A patient circling to either side has diencephalon lesion rather than cerebral lesion

Question 3

Phenobarbital MOA

Answer 3

Post synaptic, increase Cl influx causing hyperpolarization of postsynaptic terminal

At high dose, can also reduce Ca- associated action potential firing

Question 4

Keppra MOA

Answer 4

Pre synaptic SVA2 channels

Question 5

KBr MOA

Answer 5

Increase Br concentration at post synaptic terminal, diffuse into post synaptic terminal causing hyperpolarization

Question 6

Acute polyradiculoneuritis

Answer 6

No action potential in pre synaptic neuron
Suspected to be due to IM destruction of lipid membrane in nerve sheath

Question 7

Myasthenia gravis

Answer 7

Congenital: lack of AcR
Acquired: Acetylcholine receptor antibody

Question 8

Dx and rx for MG

Answer 8

Dx: tensilon (edrophonium)
Rx: pyridostigmine, neostigmine (prolong action of ach at NMJ)

Question 9

Tick paralysis MOA

Answer 9

Pre synaptic blockage of Ach release by tick neurotoxin that blocks Ca influx into presynaptic terminal

Question 10

Botulism MOA

Answer 10

Pre synaptic release of Ach

• botulism toxin cleaves SNARE protein that is needed for Ach vesicle to dock at presynaptic terminal