Neuro

Question 1

what is a migraine?

Answer 1

complex neurological condition causing episodes or attacks of headache and associated symptoms due to hypothesised inflammation, vasodilation etc

*triggers - stress, dehydration, menstruation, disrupted sleep, missed meals, bright lights

Question 2

what is a hemiplegic migraine?

Answer 2

unilateral limb weakness, ataxia, impaired consciousness

• familial can be autosomal dominant can mimic stroke or TIA

Question 3

what is the management of a migraine?

Answer 3

acute: NSAIDs, triptan, antiemetics
prophylaxis: propranolol, amitriptyline etc
other: CBT, meditation, acupunture etc

Question 4

what is the mechanism of action of triptans in the management of migraines?

Answer 4

abort migraines when they start to develop - 5-HT receptor agonists which cause cranial vasoconstriction, inhibiting transmission of pain signals and release of inflammatory neuropeptides

Question 5

what is the significance of migraines and the complications it may cause?

Answer 5

Migraines are associated with a slightly increased risk of stroke, particularly when associated with aura

• The risk of stroke is further increased with the combined contraceptive pill, making them a contraindication to the combined pill

Question 6

what is Bell’s palsy?

Answer 6

idiopathic, unilateral lower motor neurone facial palsy

• most recover within several weeks-12m

Question 7

how do you differentiate between a stroke and Bell’s palsy?

Answer 7

• forehead has only ipsilateral, unilateral innervation from LMN
• forehead NOT spared

Question 8

what are some other features of Bell’s palsy?

Answer 8

• unilateral facial weakness
• post-auricular pain
• difficulty chewing
• incomplete eye closure
• drooling
• tingling
• hyperacusis

Question 9

what are some differentials for bell’s presentation?

Answer 9

• Ramsay hunt
• infections: otitis media+externa+HIV+lyme
• systemic: DM, sarcoid, leukaemia, MS, GBS
• tumours: acoustic neuroma
• trauma

Question 10

how is Bell’s palsy managed?

Answer 10

• prednisolone in those 72h from onset
  
  • 50mg 10 days
  • antivirals
• prognosis good - reassure patient
• eye care - lubricating drops, tape when sleeping etc

Question 11

What is an essential tremor?

Answer 11

most common type of action tremor (during voluntary contraction) that typically involves the hands and is brought out by anti-gravity positions (out-stretched)

• associated with family history in autosomal dominant pattern

Question 12

how does essential tremor present?

Answer 12

• b/L voluntary tremor seen when performing task
• typical nodding
• tremor in voice when holding note
  *rarely affects legs

Question 13

what differentials would you consider in essential tremor?

Answer 13

• parkinsonism
• anxiety
• thyrotoxicosis
• hepatic encephalopathy
• CO2 retention
• cerebellar disease
• alcohol or drug withdrawal

Question 14

how is essential tremor managed?

Answer 14

• propranolol
• other: primidone, gabapentin
• neuromodulation, botulinum toxin, deep brain stimulation

Question 15

what is Horner’s syndrome?

Answer 15

IPSILATERAL ptosis, anhidrosis, miosis

Question 16

how do you differentiate the levels of lesions in Horner’s?

Answer 16

*location of anhidrosis
- face, arm and trunk: first order, spinal
- face only: post spinal cord exit, on decent down towards lung
- none: postganglionic lesions

Question 17

how would you investigate horners?

Answer 17

• systemic
• CXR
• apraclonidine to rever pupillary constriction
• hydroxyamphetamine: dilated pupil if underlying preganglionic lesion

Question 18

how is Horner’s managed?

Answer 18

• treat underlying - may restore nerve function
• neuro-imaging, discussion with hyperacute stroke unit
• thrombolysis
• anti-platelets or anticoag

Question 19

what is the pathophysiology of Subacute combined degeneration of the spinal cord?

Answer 19

• classical metabolic disorder of the spinal cord - due to vitamin B12 or folate deficiency - over 40y/o
• posterior columns and cortico-spinal tracts are specifically damaged
• symmetrical dorsal column loss - joint position sense and vibration affected

Question 20

how does subacute spinal degeneration present?

Answer 20

*impaired proprioception, vibration sensation, muscle weakness and hyperreflexia

• peripheral and CNS sings
• visual loss
• incontinence
• numbness

Question 21

how is subacute degeneration investigated?

Answer 21

• FBC - Hb low high MCV
• serum B12
• methylmalonic acid and homocysteine levels
• blood film - megaloblasts, hypersegmented polymorphs
• pernicious anaemia - intrinsic factor antibodies, parietal cell antibodies, schilling test
• MRI

Question 22

how is subacute degeneration managed?

Answer 22

• B12 replacement key! and treat cause
• most improve
  
  • peripheral neuropathy improved within first 3-6m
  • cord signs shows little improvement to treatment
• not using nitrous oxide in anaesthetising those with malnutrition or gastrectomy

Question 23

what is the pathophysiology of wernicke’s encephalopathy?

Answer 23

• disorder that occurs as a result of inadequate levels of vitamin B1 (thiamine)
• degradation of thalamic nuclei, brainstem nuclei and cerebellum and other structures around 3rd and 4th ventricles and the aqueduct
• associated with eating disorders, GI malignant, alcoholics

Question 24

What is the triad of wernickes?

Answer 24

• ataxia
• opthalmoplegia
  
  • nystagmus - horizontal and vertical
  • conjugate gaze problems
• confusion

Question 25

how is Wernicke’s managed?

Answer 25

*to prevent Korsakoff’s

• high dose IV thiamine (500mg thiamine TDS, pabrinex)
  
  • continue with oral thiamine
    *be weary of hypoglycaemia

Question 26

How does Korsakoff’s present?

Answer 26

antero and retrograde amnesia, loss of orientation in time and space, apathy to that around him, confabulation

*thiamine and adequate hydration