Neurology Flashcards
What is epilepsy? What are some causes of epilepsy?
Chronic neurological disorder w recurrent unprovoked seizures.
Genetic, neuro abnormalities, metabolic/immune disorder, chronic infection
What are the motor clinical features of epilepsy seizures?
Tonic (stiff muscles)
Clonic (rhythmic muscle jerk),
Myoclonic (shock jerks)
Atonic (loss of motor tone)
Spasms
Gabanergic vs glutamatergic
Gabanergic - GABA = main inhib neurotransmitter
Glutamatergic - glutamate = excitatory neurotransmitter
What is the pathophysiology behind a seizure?
Bursts of excitatory action potentials in neurons = synchronous hyperexcitable activity
What are the different types of seizures and how are they defined?
Focal - electrical activity is confined to one part of the brain, symptoms depend on the part of brain affected
Generalised - electrical activity affects all/most of brain, symptoms are more general and involve more of the body
What are the different types of focal seizures?
- Complex = focal impaired awareness, loss of consciousness after aura or at start of seizure, often come from temporal lobe, get post ictal sx
- Simple = focal aware, no loss of consciousness, get focal sx, no post ictal sx
What are the sx of seizure when the frontal lobe is involved?
Jacksonian features - progresses from eg. twitching in finger to twitch/tingle/weak entire hand
Dysphasia - lang disorder
Todds palsy - weakness/paralysis in body after seizure
What are the sx of seizure when occipital and parietal lobes is involved?
Parietal - tingling/numbness and motor sx
Occipital - visual sx eg. spots/lines in visual field
What does each lobe of the brain do?
Parietal - sensory, vision, comprehension of speech (Wernicke’s area), calculation and writing
Temporal - vision, hearing, olfaction, memory and emotion (amygdala) (hippocampus)
Frontal - motor, expression of speech (Broca’s area), behaviour, continence, eye movements, olfaction
Occipital - vision
What are the types of generalised seizures?
- Absence - brief loss of consciousness/awareness, no convulsion, mainly in children and last for a few seconds
- Tonic clonic - whole body stiff and loss of consciousness w convulsions
- Myoclonic - sudden jerk of limb, trunk or face
- Atonic - loss of muscle tone = pt falls, still conscious
What is the treatment for absence seizures?
Sodium valproate or ethosuximide
Carbamazepine worsens seizures
What is the treatment for tonic clonic and atonic seizures?
Sodium valproate or lamotrigine
What is the treatment for myoclonic seizures?
Sodium valproate or levetiracetam/topiramate if pt of childbearing age
Carbamazepine worsens seizures
What is the treatment of focal seizures?
Carbamazepine or lamotrigine
What are the reg regarding epilepsy and driving?
Car/motorbike:
- One off seizure = reapply in 6 months
- >1 seizure = reapply in 1 year
- Seizure after change in antiepilpetic meds = reapply to drive if seizure >6 months ago
Big vehicles:
- One off seizure = reapply in 5 years
- >1 seizure = reapply when seizure free for 10 years
What are some of the triggers of a seizure?
- Stress/anxiety
- Antidepressants and antipsychotics
- Lack of sleep/tired
- Hypoglycaemia
- Heavy alcohol
- Flashing lights
- Periods
- Fever illnesses
What are the ix into seizures?
- EEG, measures electrical activity of brain, supports diagnosis but can’t be used to exclude
- ECG - rule out arrhyhthmia
- Bloods = FBC, U&E, LFT, glucose
- MRI/CT to look for structural abnorm
What are some epilepsy mimics?
- Syncope and anoxic seizures due to loss of cerebral blood flow
- Pseudoseizures - behavioural, psychological, psychiatric
- Sleep related conditions
- Paraoxysmal movement disorders
- Migraines
What anti epileptics can you not use in child bearing aged females?
Sodium valproate
Carbamazepine to be avoided
Lamotrigine and levetiracetam safe in pregnancy
What anti epileptics interact w the pill?
Topiramate and oxcarbazepine
Levatiracetam:
- Use
- SE and contraindications
- Interactions
- Bloods needed
U - is an add on therapy, good for all seizures
SE - dizziness, headache, irritability, loss of strength and energy, behaviour changes, suicidal thoughts, drowsiness
I - doesn’t seem to have any
B - not needed ?
Lamotrigine:
- Use
- SE and contraindications
- Interactions
- Bloods needed
U - good for all seizures
SE - rash, diplopia, tremor
I - carbamazepine and phenytoin
B - not needed ?
Sodium valproate:
- Use
- SE and contraindications
- Interactions
- Bloods needed
U - good for all seizures but not in women of child bearing age
SE - weight gain, hair loss comes back curly, oedema, ataxia, tremor, teratogenicity
I - lamotrigine = extreme tiredness and slurred speech
B - LFTS and FBC 6 months after start and then every 12 months
Topiramate:
- Use
- SE and contraindications
- Interactions
- Bloods needed
U - for all types of seizures?
SE - drowsiness, diarrhoea, dizzy, nausea, weight loss, depression, don’t take if hx of glaucoma or renal stones
I - metformin, venlafaxine, diltiazem
B -
Carbameazepine:
- Use
- SE and contraindications
- Interactions
- Bloods needed
U - focal seizures, worsens myoclonic seizures
SE - SIADH, drowsiness, diplopia, ataxia, don’t use in pregnancy, blood disorders
I - anticoagulants, clarithromycin, antidepressants
B - FBC
Phenytoin:
- Use
- SE and contraindications
- Interactions
- Bloods needed
U - focal seizures, status epilepticus
SE - peripheral neuropathy, lymphadenopathy, sore/swollen gums, hirsuitism
I - other antiepilpetics
B -
What is status epilpeticus?
Seizure >30 mins or multiple seizures over 30 mins w/o complete resolution. Should be assumed at 5 mins.
Is an emergency as risk of brain damage increases as the condition persists.
What is the acute management of status epilepticus?
- Immediate management - AtoE, IV access and bloods, check BM, give O2
- 1st dose benzo - 4mg IV lorazepam or 10mg PR diazepam
- 2nd dose benzo
- IV phenytoin w ECG monitoring
- ITU - general anaesthesia and intubation w IV thiopentone
What are the Ix into status epilepticus?
Initial - O2 sats, BM
Bloods - ABG, FBC, U+E, LFT, CRP, Ca, Mg, clotting
If giving glucose in hx of alcohol abuse pt = IV pabrinex to avoid Wenicke’s encephalopathy
What qs do you need to ask in a headache hx?
Onset and duration
Nature of headache
Site of headache
Pattern and timing
Exacerbating and releiving factors
Associated sx
DH - esp analgesia use
What drugs can cause medication over use headache?
- Paracetamol, aspirin, NSAIDs if used >15 days a month
- Triptans, opioids >10 days a month
What are the red flags associated w headache?
- Thunderclap headache
- Associated fever
- Meningism
- Raised ICP = headache worse in morn, lying down and cough
- New neuro deficit or cog dysfunc
- Personality change
- Deteroriating conscious level
- Recent head injury
- New onset headache >50
- Hx of malaignancy
What are the CF of tension headache?
Tight band headache, worse at end of day, responds to simple analgesics.
Triggers - stress, poor posture, lack of sleep
What are the CF of migraine?
Throbbing, unilateral, often disabling and need to lie down
Photophobia and phonophobia
Aura
What is the management of migraine?
- Simple analgesics
- Sumatriptan (cause throat and chest tightness)
- Anti emetic eg. metoclopramide/prochlorperazine
- Amitryptylline/propanolol prophylaxis
What are the CF of med overuse headache?
Headache for 15 days or more a month, pt has existing headache disorder and reg analgesics aren’t working.
How do you manage med overuse headache?
Stop all analgesics, headaches will get worse before they get better
What are the CF of cluster headaches?
Severe unilateral stabbing pain behind eyeball, wakes you up at night. Affects men.
Runny nose, ptosis and teary eyes.
Triggers - alcohol, cigs, volatile smells, change in temp.
Normally a life long disease
What is the management of cluster headaches?
- Avoid triggers
- Verapamil prophylaxis
- Acute attack = 100% O2 and subcut/nasal triptan
What are the CF of subarachnoid haemorrhage?
- Thunderclap headache, maximal pain
- Can also have neck stiffness
- Then seizures, neurological deficits, decreased consciousness and death
- Sentinel headaches in months proceeding
How do you ix subarachnoid haemorrhage?
CT, MRI
Lumbar punc - look for xanthochromia
Cerebral angiography is gold standard
What is the prognosis of subarachnoid haemorrhage?
1/3 die
1/3 recover
1/3 disability
What is the management of subarachnoid haemorrhage?
- Surgery = clipping and coiling, thrombosis of blood in aneurysm
- CCB eg. nimodipine to prevent ischaemia
- Control raised ICP - mannitol, loop diuretics
What are the complications of subarachnoid haemorrhage?
- Vasospasm
- Hydrocephalus
- Seizures
- Rebleeding
What are the CF of a SOL?
- Headache worse on waking, lying down, coughing
- Vomiting and morning headache
- CN palsies esp abducens
- Drowsiness, seizure, pupil abnormalities, papilloedema
- Cushing’s reflex = widened pulse pressure not HTN eg. 120/80 - 120/30, brady, abnormal breathing
What are the IX into SOL?
- CT/MRI - decide if is primary or met tumour
- Biopsy if needed
- Bloods - FBC, U+E, LFTS (Na+ low in SIADH)
- CXR/mammography to find primary tumour
What are the differentials for SOL?
- Metastatic - breast, lung or melanoma
- Primary CNS tumour - meningioma (benign) or glioblastoma (malignant)
- Cerebral abscesses, more common in those who are immunosuppressed
- Haematoma
What is the management of SOL?
- Treat underlying cause
- Manage raised ICP
- Treat complications eg. anticonvulsants
- Sx treatment eg. headache, N+V
What is idiopathic intracranial HTN?
Raised ICP, mostly in young and obese women. Opening pressure >25 cmH2O
What are the clinical features of idiopathic intracranial HTN?
- Headache, features described already
- Visual disturb = visual darkening or loss, due to optic nerve ischaemia
- Drug associations - OCP, steroids, tetracycline, Vit A, lithium
- Abducens palsy
What are the ix into idiopathic intracranial HTN?
- Fundoscopy = bilat papilloedema
- BP measurement
- Urinalysis to exclude pregnancy (preeclampsia) and look for renal disease
- MRI to exclude other causes of raised ICP
- LP to measure opening pressure
What is the management of IIH?
- Weight loss, best evidence
- Carbonic anhydrase inhib (reduced CSF production), have huge list of SEs
- Therapeutic LPs
- Surgical CSF shunting in resistant cases
- Optic nerve sheath fenestration to protect against visual loss
What is the prognosis of IIH and what are the complications?
Permanent visual loss.
Recurrence can occur in 1/3rd of pt.
What are the CF of temporal arteritis?
- Jaw claudication
- Pain brushing hair
- New onset headache >50
- Decreased pulsation in temporal artery
What is the management of temporal arteritis?
Pred 60-100mg OD 2 weeks and then consider reducing.
IV methylpred for 1-3 days if acute visual sx.
Baby aspirin to avoid thrombotic events
What are the CF of intracranial venous thrombosis?
- Headache, confusion, drowsiness
- N+V
- Impaired vision
- Seizures, reduced consciousness, focal neuro deficits, CN palsies, papilloedema
- Presence of RF associated w VTE
What are the ix into intracranial venous thrombosis?
- Non contrast CT = hyperdensity in affected sinus
- CT venogram to look for filling defect - empty delta sign
What is the management of intracranial venous thrombosis?
LMWH and address RF
What are the CSF findings in different types of meningitis?
Bacterial - reduced glucose, increased protein, gram stain positive, raised WBC >1000
Viral - normal glucose, normal protein protein, WBC <300
TB - normal protein, slightly reduced glucose, WBC - 100-500
What are the CSF findings in SAH and Guillan Barre Syndrome?
SAH = xanthochromia - yellow tinge due to bilirubin from RBC breakdown
Guillan Barre = increased protein w/o increased WBC
What is normal WBC in the CSF?
< 3
What is Parkinson’s disease?
Progressive degenerative disorder due to loss of neurones in the brainstem and basal ganglia.
Dopaminergic neurone loss in the substantia nigra = inadequate dopamine transmission.
There is often Lewy Body formation in affected neurones.
What is the normal dopaminergic stimulation of the motor cortex?
Substantia nigra produces dopamine, this activates the direct pathway which inhibits the globus pallidus interna.
The inhibited globus pallidus interna can no longer inhibit the thalamus.
The thalamus therefore is able to excite the motor cortex w glutamate = movement.
What are the changes in the stimulation of the motor cortex in Parkinson’s disease?
Parkinson’s = loss of dopaminergic neurones = less dopamine. Dopamine is no longer activating the direct pathway so the globus pallidus interna is no longer inhibited.
GPi then inhibits the thalamus, reducing excitation of the cortex = reduced movement.
What are the motor features of Parkinson’s?
- Bradykinesia
- Lead pipe rigidity (resistance to passive movement)
- Asymmetric tremor eg. 4-6Hz rest tremor or pill rolling tremor
- Parkinsonian gate = small shuffling steps
- Hypomimic facies
- Micrographia
- Glabellar tap
What are the non motor features of Parkinson’s?
- Autonomic involvement - constipation, posturalhypotension, erectile dysfunc
- Olfactory loss
- REM behavioural disorder = re enacts dreams
- Depression and anxiety (reduced dopamine)
- Hallucinations
How do you distinguish IPD from other causes of Parkinsoniasm?
A significant improvement w treatment (levodopa)
What are other causes of Parkinsoniasm?
- Parkinson plus syndromes = feature motor features of Parkinson’s disease w additional features to distinguish them for IPD
- Drug induced = anti psychotics, anti emetics, lithium, methyldopa
- Post encephalitis, tremor, vascular
What drugs can be used in the management of IPD?
- Levodopa, give w carbidopa (co-careldopa) to prevent peripheral breakdown
- Dopamine agonists eg. ropinirole
- MAO-B inhibitors eg. rasagiline
- COMT inhibitors
Co-careldopa:
- MOA
- SEs
MOA - levodopa is converted into dopamine by DOPA decarboxylase once it crosses the blood brain barrier, carbidopa is a carboxylase inhib and prevents peripheral conversion
SE - N+V, dizziness
Dopamine agonists:
- MOA
- SEs
MOA - bind to dopamine receptors
SEs - sedation, hallucinations, impulse control disorders, psychiatric SE
MAO-B inhibitors:
- MOA
- SEs
MOA - prevent the breakdown of dopamine
SE - dry mouth, N+V, dizziness
What are some impulse control disorders?
- Gambling
- Hypersexuality
- Compulsive shopping
- Desire to increase dose
- Punding - repetitive motor behaviour
What are some non oral treatments used in IPD and why are they needed?
- Apomorphine injections = injectable dopamine agonist, often by infusion pump
- Deep brain stimulation = surgically inserted device that sends constant electrical signals via wires helping to manage IPD sx - akinesia, rigidity and tremor
- Duodopa = gel form of levodopa, administered via PEJ tube
Needed if patients stop becoming responsive to treatment and SEs of drugs are outweighing benefits.
What are the 4 phases of IPD?
- Early stage = sx mild and normal life is possible
- Maintenance stage - good response to treatment
- Advanced stage - poor response to drugs and there are motor SEs
- Palliative stage - unable to live independently and need MDT support
What are COMT inhibitors?
Inhibit peripheral breakdown of levodopa = more levodopa crosses blood brain barrier. Only works if use w levodopa
Eg. entacapone
What are some complications of deep brain stimulation?
Intracerebral haemorrhage and confusion
What are some motor complications of advancing IPD?
- On-off fluctuations = dyskinesia to immobility
- Dyskinesia = hyperkinetic movement eg. jerking, twitch, writhing
- Freezing of gait
- Wearing off phenomenon towards the end of dose
- Falls