Neurology Flashcards
(118 cards)
What are first line treatments for neuropathic pain? (incl. drug class)
amitriptyline - TCA
duloxetine - SNRI
gabapentin - antiepileptic (blocks Ca2+ channels to inhibit release of glutamate from pain nerve endings)
pregabalin - antiepileptic (-II-)
(monotherapy!)
PAGD - don’t want to get PAGeD about neuropathic pain
What is neuropathic pain?
pain which arises following disruption or damage of the nervous system
what are some causes of neuropathic pain?
diabetic neuropathy
post-herpetic neuralgia
trigeminal neuralgia
prolapsed intervertebral disk
Defective downward gaze and vertical diplopia - which cranial nerve is affected?
CN IV
Between which layers is the bleed in a subdural haemorrhage?
damage to the bridging veins between the cortex and the venous sinuses
Name a diuretic that can cause gynaecomastia and explain how
Spironolactone (spironoLACTone)
It competitively inhibits the binding of dihydrotestosterone (DHT) to androgen receptors
-> leading to a decrease in testosterone levels and an increase in estrogen levels
-> This hormonal imbalance results in the development of breast tissue enlargement in men.
Characteristic presentation of clostridium botulinum infection
IVDU/eating contaminated (canned) food with descending paralysis, diplopia and bulbar palsy
Spreading of reflexes
- this is an abnormal sign that can be seen on neurological examination
- when you elicit a reflex, a different muscle twitches too
Sx of MND
Presentation:
- onset usually age 50-70
- asymmetric weakness in hands/feet
- onset tends to be focal, distal and asymmetrical; progresses in a segmental fashion from one limb to the other.
- initial presentation is highly variable
- atypical/non-specific symptoms at presentation: subtle vocal changes
Life-threatening sx as the condition progresses:
- respiratory impairment
- dysphagia
Age of onset of MND + gender
50-70
more common in males (2:1)
Other names for MND
Amyotrophic lateral sclerosis (ALS) is often used synonymously (although you could also say that ALS is a subtype of MND)
Lou Gehrig’s disease
what does ALS stand for?
amyotrophic lateral sclerosis
prognosis of MND
Most patients die within 3-5 years
30% have a chance of living longer
How is MND diagnosed?
MND is a clinical diagnosis -> hx and clinical examination showing UMN and LMN signs
there is constant disease progression
there may be an element of cognitive impairment
What is the split hand sign and what condition is it seen with?
wasting pattern of the hands in which the muscles of the thenar eminence atrophy due to degeneration of the lateral portion of the anterior horn of the spinal cord.
Muscles of the hypothenar eminence are spared.
-> associated with MND (relatively specific)
-> can also be a lesion of the ulnar nerve (exclude this first)
What form of dementia is associated with MND/ALS?
frontotemporal dementia
Ix in ?MND
- MRI brain and spinal cord to exclude other causes
- EMG supports the diagnosis (shows presence of denervation) - can also see EMG changes of the tongue
- nerve conduction studies are usually normal but can show a reduction in motor nerve conduction amplitudes)
Management of MND
- supportive (there is no cure)
- see in MND specialist clinic
- MDT: includes PT/OT, Psychology, SALT, neurologist - may need noninvasive respiratory support, symptom management (e.g. cramps, spasticity, pain), walking aids, feeding tubes etc.
- consider the carer(s)
Medicines:
- Rilouzole - glutamate receptor antagonist in the CNS, prolongs survival and slows functional decline by about 3 months (-> rilouzole rilly helps Lou Gehrig’s) - check liver enzymes
What is the first line treatment of ocular myasthenia gravis?
long acting ACh esterase inhibitor
e.g. pyridostigmine
What are Broca’s and Wernicke’s areas for? What happens in Broca’s and wernicke’s aphasia?
Broca’s: Producing speech
-> B’s aphasia: Cannot speak fluently, is very effortful and halting; understands speech and can read;
->classically caused by lesions affecting the frontal lobe (think: what you say makes up who you are -> frontal lobe)
Wernicke’s: Understanding & processing speech
-> W Aphasia: speaks, however the content is non-sensical. issues with reading and repeating what was said.
-> Associated with lesions in the posterior superior temporal gyrus
B= broken speech
W= what? struggles understanding
Pyridostigmine MoA and indications
long-acting ACh esterase inhibitor
Used in:
- myasthenia gravis
what is myasthenia gravis?
an autoimmune condition affecting the NMJ
most commonly with antibodies against the ACh R
(but can be other postsynaptic antibodies)
signs and symptoms of myasthenia gravis
- diplopia
- muscle weakness
- ptosis
- blurred vision
- sx worsening after repetition of movements / worse in evening
- difficulty standing from chair/brushing hair/climbing stairs.
- bulbar muscle involvement: difficulty chewing, swallowing, dyspnoea
- often eye muscle movement issues initially, then involvement of larger muscles.
What is a myasthenic crisis and how is it treated?
worsening of muscle weakness resulting in respiratory failure needing intubation and ventilation.
treated with plasmapharesis and IVIG