Neuro Flashcards
Benign paroxysmal positional vertigo (BPPV)
Cause, sx, dx, mx
Cause:
Floating otoconia which get stuck on one of the semi-circular canals
Sx:
A variety of head movements can trigger attacks of vertigo. A common trigger is turning over in bed. Symptoms settle after around 20 – 60 seconds, and patients are asymptomatic between attacks. Often episodes occur over several weeks and then resolve but can reoccur weeks or months later.
Dx:
- Dix-Hallpike Manoeuvre
The Dix-Hallpike manoeuvre can be used to diagnose BPPV (Dix for Dx – diagnosis). It involves moving the patient’s head in a way that moves endolymph through the semicircular canals and triggers vertigo in patients with BPPV.
To perform the manoeuvre:
The patient sits upright on a flat examination couch with their head turned 45 degrees to one side (turned to the right to test the right ear and left to test the left ear)
Support the patient’s head to stay in the 45 degree position while rapidly lowering the patient backwards until their head is hanging off the end of the couch, extended 20-30 degrees
Hold the patient’s head still, turned 45 degrees to one side and extended 20-30 degrees below the level of the couch
Watch the eyes closely for 30-60 seconds, looking for nystagmus
Repeat the test with the head turned 45 degrees in the other direction
In patients with BPPV, the Dix-Hallpike manoeuvre will trigger rotational nystagmus and symptoms of vertigo. The eye will have rotational beats of nystagmus towards the affected ear (clockwise with left ear and anti-clockwise for right ear BPPV).
Mx:
- Epley Manoeuvre
The Epley manoeuvre can be used to treat BPPV. The idea is to move the crystals in the semicircular canal into a position that does not disrupt endolymph flow.
To perform the manoeuvre:
Follow the steps of the Dix-Hallpike manoeuvre, having the patient go from an upright position with their head rotated 45 degrees (to the affected side) down to a lying position with their head extended off the end of the bed, still rotated 45 degrees
Rotate the patient’s head 90 degrees past the central position
Have the patient roll onto their side so their head rotates a further 90 degrees in the same direction
Have the patient sit up sideways with the legs off the side of the couch
Position the head in the central position with the neck flexed 45 degrees, with the chin towards the chest
At each stage, support the patient’s head in place for 30 seconds and wait for any nystagmus or dizziness to settle
- Brandt-Daroff Exercises- These involve sitting on the end of a bed and lying sideways, from one side to the other, while rotating the head slightly to face the ceiling. The exercises are repeated several times a day until symptoms improve.
Delirium
Def, causes, ix, mx
Acute, transient and reversible state of confusion, usually the result of other organic processes (infection, drugs, dehydration), the onset is acute and the cognition of the patient can be highly fluctuant over a short period of time
Causes: (pinch me)
• Pain
• Infection
• Nutrition
• Constipation
• Hydration
• Medications
• Electrolyte
Ix:
- 4AT-
• Alertness- Normal (0), Mild sleepiness (0), Clearly Abnormal (4)
• AMT 4- Age, DOB, place, current year, 1 mistake = 1, 2 mistakes = 2
• Attention- Count months backwards, <7 correct = 1, Untestable = 2
• Acute change- Within 2 weeks lasting over 24 hours = 4
- AMTS-
• 8 or above (normal)
• 4-7 Mild Cognitive impairment
• 0-3 Severe
- bloods
- CXR
- CT
Mx:
- environment
- diet
- treat underlying cause
- sedation
- polypharmacy
Dementia
Types, sx, ix, mx
Types:
- Alzheimers dementia is the most common type of dementia. The underlying pathophysiology involves brain atrophy, amyloid plaques, reduced cholinergic activity and neuroinflammation.
- Vascular dementia is the second most common type. It is caused by vascular damage and impaired blood supply to the brain. Risk factors are the same as other cardiovascular diseases (e.g., hypertension, diabetes and smoking).
- Dementia with Lewy bodies is a type of dementia associated with features of Parkinsonism. It causes a progressive cognitive decline. There are associated symptoms of visual hallucinations, delusions, REM sleep disorders and fluctuating consciousness.
- Frontotemporal dementia is a rarer type that notably affects people at a younger age (starting aged 40-60). It mainly affects the frontal and temporal lobes. The initial presentation typically involves abnormalities in behaviour, speech and language. It can be familial (inherited).
Sx:
Early-
- Forgetting events
- Forgetting names
- Difficult remembering words
- Repeatedly asking the same questions
- Impaired decision making
- Reduced flexibility
Advanced-
- Inability to speak or understand speech (aphasia)
- Swallowing difficulties (dysphagia), which can lead to aspiration and pneumonia
- Appetite and weight loss
- Incontinence
Ix:
- Six Item Cognitive Impairment Test (6CIT)
- 10-point Cognitive Screener (10-CS)
- Mini-Cog
- General Practitioner Assessment of Cognition (GPCOG)
- Montreal Cognition Assessment (MoCA)
- ACE-III
- Full blood count
- Urea and electrolytes
- Liver function tests
- Inflammatory markers (e.g., CRP and ESR)
- Thyroid profile
- Calcium
- HbA1c
- B12 and folate
Mx:
- Acetylcholinesterase inhibitors (e.g., donepezil, rivastigmine or galantamine)
- Memantine, which works by blocking N-methyl-D-aspartic acid (NMDA) receptors
Ménière’s disease
Def, sx, mx
Extensive expansion of membranous labyrinth (endolymphatic hydrops)
Sx:
- vertigo
- tinnitus
- fluctuating hearing loss
- aural fullness (4th core symptom)
Mx:
- low salt diet
- caffeine restriction
- betahistine
- vestibular sedatives
- vestibular rehab
- intratympanic injections
- labyrinthectomy
- vestibular neurotomy
Stroke
Types, rf, sx, mx
Types:
- Ischaemia (inadequate blood supply) or infarction (tissue death due to ischaemia) of the brain tissue secondary to a disrupted blood supply (ischaemic stroke). Supply can be disrupted by A thrombus or embolus, atherosclerosis, shock or vasculitis
- Intracranial haemorrhage, with bleeding in or around the brain (haemorrhagic stroke)
Rf:
Previous stroke or TIA
Atrial fibrillation
Carotid artery stenosis
Hypertension
Diabetes
Raised cholesterol
Family history
Smoking
Obesity
Vasculitis
Thrombophilia
Combined contraceptive pill
Sx:
A sudden onset of neurological symptoms suggests a vascular cause (e.g., stroke). Stroke symptoms are typically asymmetrical. Common symptoms are:
- Limb weakness
- Facial weakness
- Dysphasia (speech disturbance)
- Visual field defects
- Sensory loss
- Ataxia and vertigo (posterior circulation infarction)
Mx:
- Exclude hypoglycaemia
- Immediate CT brain to exclude haemorrhage
- Aspirin 300mg daily for two weeks (started after haemorrhage is excluded with a CT)
- Admission to a specialist stroke centre
- Thrombolysis with alteplase is considered once haemorrhage is excluded (after the CT scan). Alteplase is a tissue plasminogen activator that rapidly breaks down clots. It may be given within 4.5 hours of the symptom onset, based on local protocols and by an appropriately trained team.
- Thrombectomy is considered in patients with a confirmed blockage of the proximal anterior circulation or proximal posterior circulation. It may be considered within 24 hours of the symptom onset and alongside IV thrombolysis.
- Clopidogrel 75mg once daily (alternatively aspirin plus dipyridamole)
- Atorvastatin 20-80mg (not started immediately – usually delayed at least 48 hours)
- Blood pressure and diabetes control
- Addressing modifiable risk factors (e.g., smoking, obesity and exercise)
Transcient ischaemic attack (TIA)
Def, sx, mx
Transient ischaemic attack (TIA) involves temporary neurological dysfunction (lasting less than 24 hours) caused by ischaemia but without infarction. Symptoms have a rapid onset and often resolve before the patient is seen. TIAs may precede a stroke. Crescendo TIAs are two or more TIAs within a week and indicate a high risk of stroke
Sx:
Stroke sx
Mx:
- Aspirin 300mg daily (started immediately)
- Referral for specialist assessment within 24 hours (within 7 days if more than 7 days since the episode)
- Diffusion-weighted MRI scan is the imaging investigation of choice.
Vasovagal syncope
Causes, sx, ix
Cause:
- exercise
- pain
- after food
Sx:
- warm/hot/sweaty
- nausea
- lightheaded
- disturbed vision
- tip of tongue biting
- less than 30 seconds loss of consciousness
- myoclonic jerks
Ix:
- BM
- ECG
- electrolytes
- BP
Parkinson’s
Sx, dx, ix, mx
Hypokinetic disorder
Sx:
- bradykinesia
- shuffling gait
- flexed trunk
- slow speech
- hypomimia
- reduced blinking
- micrographia
- rigidity
- lead pipe
- cogwheel
- festinant gait
- tremors
- resting, pill rolling
- improves with action
- postural instability
- falls
- autonomic disturbances
- hypersalivation
- constipation
- incontinence
- cognitive impairment
- olfactory abnormalities
- sleep disturbance
Dx:
Gradual onset that is progressive:
- Bradykinesia
- hypokinesia
And one of:
- stiffness/rigidity
- resting tremor
- balance problems
Ix:
- DAT scan
- neuro exam
- structural MRI
- CT
- serum caeruloplasmin (to exclude Wilson’s)
Mx:
- levodopa (co-careldopa)
- dopamine agonist (pramipexole)
- MAOI-B (rasagilene)
- dopamine releasers (amatadine)
- anticholinergics (benztropine)
- COMTi (entacapone)
Vertigo
Def, causes, ix
Hallucination of movement or motion
Causes:
- Central (brain or CNS)- posterior stroke, SOL, tumour, MS, demyelinatation
- peripheral (vestibular system)- BPPV, labyrinthitis, vestibular neuritis, Ménière’s disease
- HINT-
Head impulse test- asses VOR (vestibular ocular reflex) by focus on object then sharp turn, if positive then peripheral, if negative then could be central or peripheral sometimes
Nystagmus- patient looks straight ahead, left and right, if direction changing then central, horizontal nystagmus then peripheral
Test of skew- cover one eye, if vertical correction then central, absence of vertical misalignment then peripheral
Ix:
- Rinnes
- Weber’s
- neuro exam
