Neuro 2

Question 1

give 2 mechanisms by which you can develop neuropathy

Answer 1

demyelination - Schwann cell damage.
Axonal degeneration - axon damage, conduction remain intact.
Wallerian degeneration - follows nerve section.
Compression - disruption of myelin sheath.
Infarction - microinfarction of vasa nervorum.
Infiltration - by inflammatory cells, granulomas and neoplastic cells.

Question 2

what changes in the spine could there be in cervical/lumbar degeneration?

Answer 2

osteophytes, thickening of spinal ligaments, narrowing of spinal canal, disc degeneration and protrusion, vertebral collapse, ischaemic changes

Question 3

if someone is referred to you with suspected Horner’s syndrome, what do you expect to find on examination?

Answer 3

unilateral pupillary constriction with slight ptosis and enophthalmos, loss of sweating on same side

Question 4

a patient comes to see you complaining of visual loss at the ‘sides of his eyes’ on both sides and has some vague endocrine symptoms, what are you thinking is the cause, what kind of visual loss does he have and where is the lesion?

Answer 4

pituitary neoplasm pressing on the optic chiasm causing bitemporal hemianopia.

Question 5

you are performing a cranial nerve examination on a patient who has an oculomotor nerve lesion (CN3), what would you see?

Answer 5

ptosis, large pupil, eye down and out.

Question 6

what is the corneal reflex and what nerve controls it?

Answer 6

trigeminal nerve.

involuntary blinking of eye when the cornea is stimulated by something such as cotton wool.

Question 7

a small child presents to you with a vesicular rash on the side of their face, their mother says they’ve been struggling to eat recently as well - what do you suspect is the cause and how would you treat it?

Answer 7

Ramsay Hunt syndrome caused by herpes zoster/shingles, treat with fanciclovir

Question 8

name a drug that can cause sensorineural deafness?

Answer 8

gentamicin, furosemide

Question 9

what is mononeuritis multiplex? give 3 examples of causes

Answer 9

2+ peripheral nerves affected, causes tend to be systemic - WARDS PLC:
Wegener's
AIDs/Amyloid
Rheumatoid 
Diabetes mellitus
Sarcoidosis
PAN
Leprosy
Carcinomatosis

Question 10

give the 2 subtypes of gliomas

Answer 10

astrocytoma and oligodendroglioma

Question 11

name 3 types of primary malignant brain tumour

Answer 11

glioma, embryonal tumours, lymphoma

Question 12

name 2 types of benign brain tumour

Answer 12

meningioma, neurofibroma (e.g. from Schann cells)

Question 13

what is the most common cause of brain tumours?

Answer 13

metastases:

bronchus, breast, stomach, prostate, thyroid, kidney.

Question 14

what are the common sites of meningiomas?

Answer 14

parasagittal region, sphenoidal region, subfrontal region, pituitary fossa and skull base

Question 15

what are the 4 main classes of symptoms you can get from a brain tumours?

Answer 15

raised ICP, seizures, focal neurology, personality change

Question 16

what investigation would you use to stage a brain tumour?

Answer 16

CT/MRI + CXR etc to look for primary

Question 17

how would you manage a brain tumour?

Answer 17

surgical removal if possible.
IV/PO dexamethasone to reduce cerebral oedema.
phenytoin to treat epileptic seizures.
radiotherapy.

Question 18

what is the primary infection in shingles?

Answer 18

chicken pox - reactivation of herpes zoster/varicella zoster virus

Question 19

what are the clinical features of shingles?

Answer 19

dermatome distribution of rash (papules and vesicles), pain and tingling.
most common in lower thoracic dermatomes and ophthlamic division of trigeminal nerve.

Question 20

how would you treat shingles?

Answer 20

oral acyclovir or valaciclovir as early as possible

Question 21

what is the main complication of shingles and how would you treat it? how is it prevented?

Answer 21

post-herpetic neuraligia - pain in distribution of affected nerves.
treat with carbamazepine or phenytoin.

prevented by prompt antiviral treatment.

Question 22

how do anti-epileptic drugs work?

Answer 22

they work on sodium channels to inhibit action potentials to stop continuous firing of neurones

Question 23

pyridostigmine is used in a neurotransmitter disease, which one and how does it relieve symptoms?

Answer 23

myasthenia gravis - acetylcholinesterase inhibitor, which means ACh is around longer to attach to the post-synaptic membranes

Question 24

baclofen is used for muscle spasticity in what disease, and how does it work?

Answer 24

Huntington’s chorea - GABA agonist.

Question 25

what type of drug do you prescribe in trigeminal neuralgia?

Answer 25

anti-epileptic, carbamazepine

Question 26

ceftriaxone is prescribed in bacterial meningitis, what class of antibiotic is it?

Answer 26

3rd generation cephalosporin

Question 27

give 2 examples of benzodiazepines. what are they used for?

Answer 27

diazepam, lorazepam, chlordiazepam - first line management of seziures and status epilepticus, management of alcohol withdrawal rections.

Question 28

how do benzodiazepines work?

Answer 28

target the gamma-aminobutyric acid type A (GABA-a) receptor, which is a chloride channel that opens in response to binding by GABA (main inhibitory neurotransmitter) - opening the channel makes the cell more resistant to depolarization.

benzodiazepines facilitate and enhance binding of GABA to GABA-a receptors and have a widespread depressant effect on synaptic transmission - cause reduced anxiety, sleepiness, sedation, anti-convulsion.

Question 29

what is carbamazepine used to treat?

Answer 29

epilepsy - focal seizures ± secondary generalisation and for primary generalised.
trigeminal neuralgia.

Question 30

how does carbamazepine work?

Answer 30

inhibits neuronal sodium channels, stabilising resting membrane potentials and reducing neuronal excitability.

this may inhibit spread of seizure activity, and control spread of neuralgic pain by blocking synaptic transmission.

Question 31

what are valproates used for? name one.

Answer 31

epilepsy - 1st choice for generalised/absence seizures and focal seizure treatment.
sodium valproate, valproic acid.

Question 32

what are gabapentin/pregabalin used to treat?

Answer 32

focal epilepsies as an addition to carbamazepine.

also for neuropathic pain and migraine prophylaxis.

Question 33

how does gabapentin work?

Answer 33

closely related to GABA - binds to voltage sensitive calcium channels, preventing inflow of calcium and thus inhibiting neurotransmitter release, interfering with synaptic transmission and reducing neuronal excitability.

Question 34

give some examples of dopaminergic drugs

Answer 34

levodopa (as co-careldopa, co-beneldopa), ropinirole, pramipexol

Question 35

how do dopaminergic drugs work to treat Parkinson’s?

Answer 35

there’s a dopamine deficiency in Parkinson’s - treatment increases dopaminergic stimulation to the basal ganglia.
levodopa = dopamine precursor that is able to cross the BBB.
ropinirole and pramexipol = selective agonists for the D2 receptor, which predominates in the basal ganglia - used to delay starting levodopa.

Question 36

what is levodopa always given with? why?

Answer 36

a peripheral dopa-decarboxylase inhibitor e.g. carbidopa - combined preparations (co-careldopa, co-beneldopa).
this is to reduce conversion to dopamine outside the brain, reducing SE of nausea, and lowering the dose.

Question 37

what class of drug do rivastigmine and neostigmine belong to? what are they used to treat?

Answer 37

acetylcholinesterase inhibitors.

Alzheimer’s disease, Lewy body dementia and Parkinson’s disease. also myasthenia gravis.

Question 38

how do acetylcholinesterase inhibitors work as neurological drugs?

Answer 38

inhibit ACh break down. in neurodegenerative disorders they are used to treat memory and learning deficit symptoms - improve due to role of ACh in cognition.
in myasthenia gravis there are too few ACh receptors, so with greater ACh availability, symptoms improve.