Lectures : Neuro Flashcards
Name grading scores used to predict prognosis and outcome in patients with subarachnoid haemorrhage?
- Hunt and Hess
- World Federation of Neurosurgeons
Definitive treatment for SAH
- transfer to specialist neuro unit
- analgesia and anti-emetic
- metallic coils (radiological) / surgical clipping
- ICP monitoring
- BP management
- Nimodipine po 60mg / 4hrly (within 48hrs)
Notes: Endovascular coiling
Complications of SAH
- re-bleeding
- subdural haemorrhage
- global cerebral ischaemia
- vasospasm
- hydrocephalus
- seizures
- SIADH / cerebral salt wasting syndrome
What might be given to help reduce risk of re-bleeding in SAH?
Nimodipine po 60mg / 4hrly (within 48hrs)
What is used to pathologically classify brain tumours?
- The WHO classification
- based on cells affected
- nerves —> schwannoma
The commonest primary brain tumour is glioma, this is further classified onto what the cells look like under a microscope. Name the cells:
- Astrocytes
- Oligodendrocytes (myelin sheath !)
- Ependymal cells (line ventricular system)
What genetic deletion is associated with oligodendroglioma?
1p 19q deletion
IDH1 mutation is associated with what type of brain tumour?
astrocytoma
In patients with glioblastoma what type of genetic change may be seen?
MGMT promotor methylation
- patients with methylation will respond better to chemotherapy.
- methylated - blocks
MGMT which would normally break down chemotherapy, does better with treatment
This is used to measure cancer patients ability to carry out ordinary tasks
Karnosfsky performance status
What is spectroscopy and why is it used?
Looks at chemical composition within defined area of brain.
N-ACETYL-ASPARTATE PEAK
- marker of cell turnover, if cells turning over suggests tumour
What drug is given to patients before brain surgery that will given a deep red hue to the patients tumour?
5 -ALA
- tumour lights up under UV light
Name of a chemotherapy that can be placed like wafers on the tumour and gently diffuses into the tumour
Gliadel
While chemotherapy does not tend to work that well on the brain given an example of a type of chemotherapy drug that does?
temozolamide
- works better in MGMT methylated patients
What two special tests/ signs might indicate meningitis?
KErnig sign
- knee extension is painful
Brudzinski sign
- neck flexion leads to knee flexion
What tools may be used for cognitive function assessment?
- MOCA - Montreal cognitive assessment
- Addenbrooke’s cognitive assessment
Presence of hypertension with bradycardia is known as what sign?
Cushing’s sign
- systolic BP
- decreased pulse
- decreased respiration
What monitoring is important in the treatment of HSV encephalitis?
- renal
- aciclovir may lead to crystal nephropathy
In immunocompromised patients, what are the likely viral causes of encephalitis?
HHV 6 –> Roseola
HHV 7 –> pityriasis rosea
HHV 8 –> Kaposi sarcoma in HIV individuals
EBV
CMV
Pathophysiology of viral encephalitis
- via cranial nerves –> HSV
- via peripheral nerves –> Rabies
- neuroinvasion from blood (in plasma e.g. flaviviruses, Japanese encephalitis) or by infecting leukocytes (HIV)
autoimmune encephalitis caused by what:
antibodies against NMDA receptor
How is the diagnosis of epilepsy made?
- at least two unprovoked seizures occurring greater than 24 hours apart
- one unprovoked seizure and increased probability of further seizures
What is an arteriovenous malformation?
- abnormal connection of blood vessels
- can be associated with seizures and epilepsy
What investigations are required for a suspected thunderclap headache?
- URGENT IMMEDIATE CT BRAIN
IF CT unremarkable for cause
- LP and CSF examination (12hrs post headache)
Why the 12hr gap?
- if there is blood in CSF not picked up by CT
- this will break down to bilirubin
- bilirubin can be picked up on a xanthochromia test
Management of headache caused by low CSF pressure?
- lie flat (1 -2 weeks?)
- IV fluids 8hrly or 2-3L oral fluids in 24 hours
- gives time for brain to heal dura
Red flags for glaucoma
loss of vision and halo effect
Give example of neuropeptides involved in the trigemino cervical complex pathway of migraine genesis:
CGRP
- calcitonin gene related peptide
Management for episodic migraine
- Triptans AND/OR Aspirin OR NSAIDs should be 1st line therapy
-
Triptan + NSAID + anti-emetic
- after aura!
- given as one off
- ensure adequate hydration
- Rest
- Don’t use strong painkillers
When should migraine suffers be evaluated for use of preventive therapy:
- if getting more than 2-3 episodes a month
- or if episodes are severe
Chronic headaches are defined as what frequency of headaches:
- more than 15 days a month
- for more than 3 months
- at least 8 days in the month have features of migraine
- triggers!
Treatment of cluster headaches
- Acute treatment
- Sumatriptan - injection / nasal spray
- high flow oxygen
Treatment of cluster headaches
- short term prevention
- greater occipital nerve blocks
- prednisolone 60-80mg/day 3-5 days and taper off (counsel on side effects and lansoprazole)
- should not be used more than twice a year
Treatment of cluster headaches
long term prevention
- verapamil
- topiramate
- lithium
- gamma core device
Management of neuralgia :
Carbamazepine (usually responsive)
Define multiple sclerosis
- multifocal , upper motor neuron disorder
- multiple sclerotic lesions
- relapsing or progressive
- dissemination in time and space
radiographic feature of demyelination seen in multiple sclerosis
Dawson’s fingers
How is the diagnosis of multiple sclerosis made:
Poser 1983
- 2 attacks with objective clinical evidence
- attacks occurring at different times
MRI may also be used
Macdonald criteria
Management of MS
- Relapsing treatment
- 500mg Methylprednisolone for 5 days
- Relapse prevention
- specialist stuff
- e.g. interferons
- Slowing progression
- Neural repair
- re-myelination? stem cells?
Define Parkinson’s disease
- progressive reduction of dopamine
- in basal ganglia of brain
- leads to disorder of movements
Key features
1. Resting tremor (4-6hz)
2. Cog wheel rigidity
3. Bradykinesia
What histopathological features are present in Parkinson’s disease:
- Lewy Body Depositions
- composed mainly of alpha synuclein protein
- Diminished substantia nigra
Appearance of substantia nigra in Parkinson’s disease:
lighter
Parkinson’s tremor vs benign essential tremor
Parkinson’s tremor
–> asymmetrical
–> 4-6hz
–> worse at rest
–> improves with intentional movement
–> no changes with alcohol
Benign essential tremor
–> symmetrical
–> 5-8hz
–> improves at rest
–> worse with intentional movement
–> improves with alcohol
Summarise the Parkinson’s plus syndromes which also exist:
- Multisystem atrophy
- Dementia w/ lewy bodies
- Progressive supranuclear palsy
- Corticobasal degeneration
Management of Parkinson’s disease
- Levodopa
a) synthetic dopamine
b) usually combined with peripheral decarboxylase inhibitors
–> carbidopa or benserazide
–> prevents breakdown of levodopa before entering brainCombination drugs are:- Co-benyldopa (levodopaandbenserazide)
- Co-careldopa (levodopaandcarbidopa)
Main side effect of high levels of dopamine:
Dystonia –> excessive muscle contraction
Chorea –> abnormal involuntary movements jerking
Athetosis –> involuntary twisting movements
What is the role of COMT inhibitors:
e.g. entacapone
- COMT enzyme metabolises L-dopa in both body and brain.
- Entacapone is taken with L-dopa (and decarboxylase inhibitor) to slow breakdown of L-dopa
- extending duration of levodopa!
What is the name of enzyme which breakdowns neurotransmitter dopamine
monoamine oxidase B
- more specific to dopamine
- thus monoamine oxidase-B inhibitors will be used to increase circulating dopamine.
What condition is important to consider in a patient with cerebrovascular risk factors and Parkinsonism type symptoms:
- Vascular Parkinsonism
- predominant gait and postural instability
- tremor less prominent
- poor levodopa responsiveness
Side effects of dopamine agonists
- Impulse control disorders: pathological gambling, binge eating and hypersexuality
- Somnolence: strong desire to fall asleep
- Confusion, hallucinations
Examples of MAO-B inhibitors
Increase amount of dopamine available for receptors in the striatum.
Rasagiline and Selegiline
MAO-B inhibitor associated with hallucinations, confusion and insomnia
Selegiline
Drug which prevents reuptake of dopamine at synapses
Amantadine
Used only for the management of levodopa-induced dyskinesia
What are 3 other drug induced movement disorders important to be aware of:
-
Akathisia
- motor restlessness
-
Tardive Dyskinesia
- smacking of lips
- facial grimacing
- lateral jaw movements
- choreiform (jerking) or athetoid (slow involuntary writhing of fingers) movements
-
Dystonia’s
- Torticollis
- oculogyric crisis
What is the precursor for dopamine and how is this converted to dopamine:
2 broad categories of dopamine agonists:
- Ergot-based (not used as much)
- pergolide, cabergoline
Adverse effects of Ergot based drugs
- pulmonary, pericardial and retroperitoneal fibrosis
- Non-ergot
- pramipexole, ropinirole
Treatment of essential tremor:
- B-blockers
- propranolol
Treatment of dystonia:
- botulinum toxin injections
- weaken affected muscle
Absent seizure AEDs
1st line - ethosuximide
2nd line - sodium valproate
Focal seizure AED
1st - Carbamazepine, sodium valproate, levetiracetam
Generalised seizu
Common side effect of levetiracetam
behavioural problems
Common side effects of carbamazepine
Steven Johnson Syndrome
Behavioural problems
Common side effects of nitrazepam
drowsiness
Common side effects of vigabatrin
visual field defects
Common side effects of topiramate
weight loss
Name the 6, cytochrome P450 hepatic enzyme inducers:
‘Randy’s car smokes and goes poot poot’
- Rifampicin
- Carbamazepine
- Spironolactone
- Griselfulvin
- Phenytoin
- Phenobarbituate
Describe the 3 categories of AEDs and what this means in terms of prescribing:
Category 1 —> should not switch between brands
—> carbamazepine
—> phenobarbital
—> primidone
Category 2 —> clinical judgement whether to switch or not
—> sodium valproate
—> lamotrigine
—> perampanel
Category 3 —> can switch between different versions
—> levetiracetam
—> gabapentin
Scoring system for myelopathy
mJOA scoring system
