Neurology Flashcards
First-line for migraine
Oral triptan with NSAID (taken during headache, not aura)
First-line prophylaxis for migraine
Propranolol or topiramate [teratogenic]
Second-line: gabapentin
Emergency mx of TIA in primary care
Consider 300 mg aspirin (unless known bleeding disorder, anticoagulated, already taking regular low-dose aspirin)
Long-term medical management TIA
300 mg aspirin initially (if not contraindicated)
75 mg clopi
80 mg atorvastatin
Control hypertension: ACEi + diuretic
Inform DVLA
Red flags for head injury
High risk mechanism of injury Reduced GCS LOC Retrograde amnesia (>30 mins) Post-traumatic amnesia (> 5 mins) post-traumatic seizures focal neurology Vomiting (twice or more) Persistent headache not relieved by simple analgesia Coagulopathy/ taking anticoags New or ongoing sx
> 65, alcoholism
Consider NAI
Warning patients about concussion following head injury
Dizziness, headaches, poor concentration, visual disturbance
Responsible adult must also be given info (and stay for 24h)
Pain relief for uncomplicated head injury
Not opiates in case need to check pupil size
Describe seizure in layman terms
A seizure is caused by a disruption of the electrical activity in the brain
Red flags for LOC
Focal neurology, first seizure
TIA, HF
When can LOC be diagnosed as faint?
No evidence of alternative diagnosis and 3 Ps:
Posture
Provoking factor
Prodromal sxE
Emergency mx temporal arteritis
60 mg pred stat
main causes of death due to head trauma
traffic collision and alcohol
PRIMARY vs SECONDARY BRAIN INJURY
P: direct irreversible damage
S: within hours/ days - hypoxia, ischaemia, infections etc
Head injury and GCS bands
13-15: mild injury
9-12: moderate
3-8: severe
COUP vs CONTRECOUP LESIONS
at point of impact vs opp side (may be more extensive/ severe)
vessels affected by extradural haemorrhage
middle meningeal
presentation of extradural
brief LOC, lucid period of minutes/ hours
followed by rapid loss of consciousness
vessels affected in subdural haeorrhage
bridging veins passing between cerebral cortex and dural venous sinuses
Cushing’s response
Raised ICP, leading to
Arterial HTN
Bradycardia
Buying time when raised ICP
Hyperventilation reduces arterial CO2 –> cerebral vasoconstriction –> reduces intracranial blood volume
When is post-traumatic epilepsy considered ‘early’ or ‘late’
early within first week
CONCUSSION
Head injury sufficient to cause LOC
What is ischaemic penumbra
area is damaged but viable if bloodflow restored
Definition TIA
Full recovery within 24h
Amaurosis fugax is caused by TIA in which territory
carotid territory
what % strokes are ischaemic?
85%
Prior to limbs becoming spastic instroke what are they like?
Flaccid, fall like dead weights when dropped
Posterior circulation infarcts may cause ‘crossed syndrome’. What is this?
Ipsilat cranial nerve deficit
Contralat limb deficit
What are lacunar infarcts?
Basal ganglia, internal capsule, thalamus, pons
What is ABCD score for?
People with TIA who may go on to have stroke
If +4, give 300 mg aspirin
What usually causes SAH?
Bleeding from berry aneurysm in circle of willis
Relevance of family history in SAH
x3-7 compared to general population if first-degree relative
Second degree: no link
How relevant is sudden explosive headache in diagnosing SAH?
10% will have SAH
When do sentinel bleeds tend to occur?
~3 weeks before SAH
What Ix for SAH?
CT scanning
CT angio
LP (after 12h)
Why is nimodipine given in SAH?
CCB to avoid vasospasm - affects 1/3 pts and can lead to ischaemic brain injury
Triad: normal pressure hydrocephalus
dementia, gait disturbance, incontinence
Communicating vs non-communicating hydrocephalus
non-comm = obstructive (congenital or acquired blockage)
comm = reduced absorption, increased production etc.
What is hydrocephalus?
increased CSF
Causes of focal damage affecting cerebral function
vascular events, tumours, trauma, localised inflammatory lesion (abscess, tuberculoma)
Causes of generalised or multi-focal damage
degenerative disease, multi-focal infarcts, demyelination, diffuse infection (meningitis, encephalitis)
Definition of dominant side
Controls writing and speech
In how many is the L side dominant
90% R-handers
60% L-handers
Where is the primary motor cortex? What does it contain?
Precentral gyrus in frontal lobe
Umns organised in homonculus - contralateral
Name of cortices co-ordinating and planning complex movements. Location
Supplementary motor and premotor cortices (frontal): co-ordinating and planning complex movements
Which part of cortex sorts eye movements?
Frontal eye fields (contralateral side)
Where is Broca’s area - what does it control?
dominant side frontal lobe
motor/ ‘expressive’ speech
What does the pre-frontal cortex control?
personality, emotion, planning
Blood supply of frontal lobe
ACA: medial surface, i.e. leg
mca: lateral surface, i.e. face and arm
Which lobe is cortical micturation centre
frontal lobe
Pathology of frontal lobe
Frontal seizures Contralateral weakness/ gait apraxia Conjugate eye deviation (towards lesion) Expressive dysphasia (has insight) Personality change Primitive reflexes Incontinence
What is located in the parietal lobe?
Primary somatosensory cortex (postcentral gyrus, contralateral) Language (dominant side): arcuate fasciculus connecting Broca's + Wernicke's Calculations (also dominant) Integration of somatosensory, visual + auditory info (non-dominant) Visual pathways (pass deep within parietal lobe)
Blood supply of parietal lobe
mCA
Name if one limb lost motor control. If half of body.
monoparesis/ hemiparesis
Pathology if dominant parietal lobe affected
Wernicke’s receptive dysphasia (neologisms, paraphrasia, poor insight)
Dyscalculia, dysgraphia
Inability to distinguish R + L sides of body
Pathology if non-dominant parietal lobe affected
Contralateral sensory inattention
problems following sequences etc.
Pathology if parietal lobe affected (both lobes affected in these ways)
Cortical contralateral sensory loss (doesnt impair sensation, just ability to make sensory judgements)
If deep, contralateral homonymous inferior quadrantanopia
Where is Wernicke’s area?
Dominant temporal lobe
Blood supply of temporal lobe
MCA (lateral lobe)
PCA (medial lobe)
Where are the auditory and vestibular cortices?
temporal
Dominant: comprehension of spoken word
non-dom: sounds/ music
A stroke of which vessel may cause global dysphasia
L MCA
Pathology when temporal lobe affected
Wernicke’s dysphasia
Auditory agnosia
Cortical deafness
Memory impairment (hippocampus and parahippocampal gyrus)
Visual disturbance: contralateral superior homonymous quadrantanopia
Blood supply of occipital lobe
PCA
except occipital poles (serving macular vision - they’re MCA)
Triad of Korsakoff’s. Cause. Type of amnesia
Memory loss, ataxia, nystagmus
thiamine deficiency secondary to chronic alcoholism
dense retrograde amnesia and confabulations
What is syringomyelia? How does it present?
Central canal becomes enlarged, compressing adjacent nerves
spinothalamic can be selectively lost, causing temp/ pain loss in upper limbs (cape pattern)
what commonly causes subacute combined degeneration of spinal cord? how does it usually present? how treated?
why called combined?
B12 deficiency falls at night (sensory ataxia with impaired vision) treated with B12! Dorsal columns: sensory ataxia and LMN Corticospinal: UMN
Which pathways predominantly affected in tabes dorsalis?
Dorsal columns (sensory ataxia/ high-stepping gait)
What is Friedrach’s ataxia? how is it inherited?
autosomal recessive
degen of many nerve tracts
cerebellar signs
begins in childhood
what is clasp-knife rigidity
increased tone where there is initial resistance followed by relaxation
what is pyramidal weakness
UMN sign
weakness of extensors of upper limb, flexors of lower limb
parkinsonism triad
akinesia
rigidity
dyskinesias
(if unilat lesion these will be contralateral)
[Huntington’s on other side of spectrum where selective death in striatum causes hyperkinesia)
which IV disc most commonly affected by sciatica
L5/S1
which nerve compressed in meralgia paraesthetica
lateral cutaneous nerve
what causes diabetic ulcers?
neuropathy can prevent adequate redistribution of blood to the ulcer, lack of sweating render skin dry/ cracked
What causes myaesthenia gravis?
Binding of autoantibodies to components of NMJ, most commonly the acetylcholine receptor
What is Lambert-Eaton associated with?
small cell cancer
What is GBS? How is it characterised?
disorder causing demyelination and axonal degeneration resulting in acute, ASCENDING, progressive neuropathy
weakness, paraesthesiae, hyporeflexia
usually reaches maximum at 2 weeks, stops progressing after 5 weeks
What usually precedes GBS?
Infection of respiratory/ GI tract
Mx GBS
plasma exchange
IV Ig
CS
What does normal conscious state depend on (light bulb analogy)
Brainstem RAS
both cerebral hemispheres
Define syncope.
General causes.
Global reduction in blood flow to brain
Vasovagal syncope Situational syncope Postural hypotension Syncope due to cardiac dysfunction Carotid artery disease
Why do people collapse in vasovagal?
VASO: peripheral vasodilatation leads to low BP
What is convulsive syncope?
if persists –> cerebral hypoxia
eyes roll up, brief myoclonic jerks
usually: sphincter control maintained, no postictal state (maybe malaise)
What combination of things causes micturition syncope
vasodilatation (from emptying bladder)
postural hypotension
bradycardia
how to investigate carotid sinus disease
carotid sinus massage on ECG
Sign of carotid sinus disease
carotid bruit
DVLA and LOC
must inform (unless vaso-vagal with clear precipitant)
cardiovasc causes: 4 weeks after treatment
otherwise: 6 months
NARCOLEPSY vs CATAPLEXY
excessive sleepiness vs drop attacks (brought on by excitement/ emotion)
STATUS EPILEPTICUS
continued or recurrent seizures with failure to regain consciousness over 30 mins
what causes incidence of grand mal seizures to rise in 50s-60s?
subcortical ischaemic changes secondary to HTN
New classification of focal-onset seizures
focal impaired awareness seizure
focal aware seizure
how to tell focal to bilat tonic-clonic vs generalised-onset
asymmetry consistent in first
in generalised, lateralisation not consistent from seizure to seizure
AEDs for generalised epilepsy
sodium valproate
lamotrigine
AEDs for focal epilepsy
carbamazepine, lamotrigine
what elicits lhermitte’s phenomenon
neck flexion
cervical cord demyelination
Types of MS
Relapsing-remitting
Secondary progressive (just get worse, many R-R convert to this)
Primary progressive (declines from beginning)
imaging to show MS
T2-weighted MRI scan
meds for muscular stiffness
baclofen
what is an intention tremor
increases during movement
alcohol helps what kind of tremor
essential tremor
thiamine is which vitamin
B1
What kind of meningitis may occur in those with splenectomy/ SCD?
encapsulated organisms
Which microorganism causes outbreaks of meningitis at unis?
N.meningitidis
What organisms cause meningitis in adults?
S.pneumoniae
H.influenzae
N.meningitidis
Staph, strep etc
What organisms cause meningitis in HAI or post-trauma?
E.coli
Klebsiella
Pseudomonas aeruginosa
Staph aureus
may be multi-drug resistant
What causes of meningitis may be seen is immunocompromised?
syphilis, TB
Causes of aseptic meningitis
Partly-treated bacterial meningitis Viral Fungal Parasites Kawasaki disease
Causes of non-infective meningitis
Malignant cells (leukaemia, lymphoma, others)
Sarcoid
SLE
Behcets
Ix for meningitis
FBC CRP Coagulation screen Blood culture Gases Glucose
Often others like CXR, cultures for urine, nasal swabs, stool etc
Rules for giving benzylpenicillin in community
If septicaemia
If will take a while to get to hospital
IM or IV
What treatment may close contacts of acute bacterial men receive?
Prophylactic abx
What sort of neurological complaints are seen in coeliac disease?
10% have ataxias, neuropathies
What sort of neurological complaints are seen in IBD?
small % demyelinating peripheral neuropathy
Adults needing CT within 1 hour following head injury
GCS less than 13 on initial assessment in the emergency department.
GCS less than 15 at 2 hours after the injury on assessment in the emergency department.
Suspected open or depressed skull fracture.
Any sign of basal skull fracture (haemotympanum, ‘panda’ eyes, cerebrospinal fluid leakage from the ear or nose, Battle’s sign).
Post-traumatic seizure.
Focal neurological deficit.
More than 1 episode of vomiting.
Holmes-Adie pupil
normal varient
young woman
large irreg pupil, slow and incomplete constriction to light
absent ipsilateral deep tendon reflexes
sometimes problem w/ efferent parasympathetic
Argyll Robertson pupil
neurosyphilis
Dm
ms
miosis, irreg pupil, absent light reflex, intact accommodation
where do spinal nerves pass?
C1-7 above vertebrae, then below
what do the dorsal columns carry?
touch, pressure, vibration, proprioception
what do the spinothalamic tracts carry?
temp, pain - lateral tracts
crude touch, pressure - anterior tracts
can there be muscle weakness in umn lesion?
pyramidal weakness
which cranial nerves carry info on taste?
facial - first two-thirds
glossopharyngeal - posterior 1/3
how to detect RAPD
shine light in unaffected eye: both constrict
in affected eye: constrict to a lesser degree
how may posterior communicating artery aneurysm present?
third nerve palsy
how does third nerve palsy appear?
looking down and out
fixed dilated pupil
which nerve affected shows trouble down the stairs?
CN IV
nerve most commonly affected in head injury?
abducens
commonly affected by raised ICP too
causes of sixth nerve palsy
microvascular disease
external compression from acoustic neuroma, raised ICP
how to spot sixth nerve palsy
drifts towards midline when asked to look forward
acute mx cluster headache
oxygen + triptan
prophylaxis cluster headache
verapimil
mx trigeminal neuralgia
carbamezapine
what is encephalitis?
inflammation of the brain parenchyma
triad of encephalitis
fever
headache
altered mental status
most common cause of encephalitis
HSV-1
mx acute relapes ms
oral pred or IV methylprednisolone
doesnt alter prognosis
spondylosis vs spondylolisthesis
spondylosis: age-related degeneration of spinal cord (commonly OA)
spondylolisthesis: anterior pr posterior displacement of vertebra (not disc)
triad of parkinsons
bradykinesia, resting tremor, rigidity
painful third nerve palsy
PCA aneurysm rupture
3rd nerve palsy with pupillary sparing
stroke
