Neuro Flashcards
what area of the brain is involved with comprehension and understanding of speech? where in the brain is this? what is its main blood supply?
Wernicke’s area. superior temporal gyrus of the dominant hemisphere. middle cerebral artery.
what area of the brain is involved with the production of speech? where in the brain is this? what is its main blood supply?
Broca’s area. frontal lobe of the dominant hemisphere. middle cerebral artery.
What main symptoms would make you suspect stroke in any patient?
- unilateral weakness or paralysis in the face, arm of leg
- dysarthria or expressive or receptive dysphasia
- vision problems
- headache (sudden severe)
- difficulty with coordination and gain
- vertigo or loss of balance
- symptom onset after awakening from sleep
how would an ischaemic stroke of the anterior cerebral artery present?
- limb and/or facial weakness
- expressive and/or receptive dysphasia
- Sensory loss in face and upper and/or lower extremities
- vision loss in one eye or visual field deficit
- gaze paresis (often horizontal and unidirectional)
- homonymous quadrantanopia
What are the clinical features of a posterior circulation stroke?
- double vision
- Motor and/or sensory deficit
- motor: weakness, clumsiness, paralysis of any combination of arms and legs, up to quadriplegia
- Sensory: numbness, sometimes including all four limbs or both side of the face
- Vertigo, with possible nausea and vomiting
- ataxia - loss of full control of bodily movements
- dysarthria
- dysphagia
- homonymous hemianopia
- altered level of consciousness and coma
What are the 4 classifications of stroke?
- Total anterior circulation stroke
- Partial anterior circulation stroke
- Posterior circulation stroke
- Lacunar Syndrome
at what point do symptoms become a stroke, rather than a TIA?
if they last over 24h.
what specific investigation would you carry out if you suspected that atherosclerosis had caused your patient’s TIA? what treatment would you consider?
carotid Doppler and carotid endarterectomy.
name 3 risk factors for a TIA
hypertension, smoking, obesity, diabetes, high alcohol intake, combined oral contraceptive pill, hyperlipidaemia, haematology disorders
90% of TIAS affect the anterior circulation, what are the symptoms of this?
- symptoms are usually unilateral and affect the motor area, causing unilateral weakness
- hemiparesis
- may be sensory problems in the same areas
- Broca’s dysphasia
- Amaurosis Fugax
what is amaurosis fugax?
progressive loss of vision in one eye - “like a curtain descending over my field of view” - due to emboli passing into the retinal artery
name 2 differential diagnoses of a TIA
hypoglycaemia, migraine, focal epilepsy, retinal bleeds, syncope, intracranial lesion
what is the ABCD2 score and what is it used for?
used to predict progression to full stroke after TIA:
Age >60yo
BP >140/90
Clinical features - unilateral weakness, speech disturbance without weakness.
Duration of symptoms - >1h or 10-59min.
Diabetes.
how would you treat a TIA?
300mg Aspirin STAT once haemorrhage ruled out
control hypertension/hyperlipidaemia/diabetes.
smoking cessation.
antiplatelet drugs - clopidogrel/aspirin/warfarin. ± carotid endartectomy.
how does warfarin work to reduce platelet aggregation?
inhibits vitamin K dependent synthesis of clotting factors 2, 7, 9 and 10
list 4 risk factors for stroke
Older age, family history of stroke, hypertension, smoking, diabetes, AF, cardiac/haem conditions, ethnicity (asian, black and/or Hispanic), alcohol
what are the 2 main types of stroke?
ischaemic and haemorrhagic
list 5 causes of haemorrhagic stroke
hypertension, trauma, aneurysm rupture, anticoagulation, thrombolysis, carotid artery dissection, subarachnoid haemorrhage
what might be some pointers in the presentation of stroke, to whether it is due to haemorrhage or ischaemia?
In haemorrhagic:
- more likely to lose consciousness
- more likely to have headache (sudden onset)
- neurological defects are usually sudden (like embolic stroke) but are more likely to be progressive
- patients on oral anticoagulants should be assumed to have haemorrhage unless it is proved otherwise
what would be the clinical features of a brainstem infarct?
quadriplegia, disturbances of gaze and vision, locked-in syndrome
what are the 5 different syndromes produced by lacunar infarcts?
- pure motor loss
- pure sensory loss
- sensorimotor disturbance
- ataxic hemiparesis (cerebellar and motor symptoms)
if a patient presented with vertigo, headache, ataxia and vomiting, what structure has been affected and what vessel has caused it?
cerebellar syndrome - due to occlusion of superior, anterior inferior or posterior inferior cerebellar artery
what is the essential investigation to carry out before you start specific stroke treatments?
urgent CT head
give 3 differential diagnoses of stroke
head injury, hypo/hyperglycaemia, subdural haemorrhage, intracranial lesion, migraine, epilepsy, drug overdose
if CT showed that the stroke was caused by an infarct, how would you treat it?
thrombolysis - aspirin and alteplase (recombinant tissue plasminogen activator (tPA))
What is the maximum amount of time thrombolysis can be given after a stroke
4.5hrs post onset of symptoms
What is the treatment for a Haemorrhagic stroke
- Any anticoagulants should be reversed
- Control hypertension if possibility of severe hypertensive crisis
- Manual decompression of raised ICP or by giving Mannitol
What are the factors in CHA2DS2-VASc and what is it used for
To calculate stroke risk with AF:
Congestive heart failure = 1
Hypertension: consistently above 140/90 = 1
Age 65-74 = 1
>74 = 2
Diabetes = 1
Stroke/TIA/thromboembolism previously =2
Vascular disease = 1
Sex category = 1 if female
Offer anticoagulation in patients with a score of 2 or above
give 2 examples of primary prevention of stroke
Antiplatelet therapy, treat hypertension, control DM, statins for hyperlipidaemia, regular physical exercise, smoking cessation, anticoagulation after stroke from AF
list the causes of subarachnoid haemorrhage
rupture of saccular (Berry) aneurysms - 80%. AV malformations - 15%. idiopathic.
list 3 risk factors for subarachnoid haemorrhage
smoking, alcohol misuse, hypertension, bleeding disorders, diseases that predispose to aneurysms: polycystic kidney, Ehlers Danlos, coarctation of aorta
what are some common sites for Berry anuerysms?
junction of posterior communicating artery with internal carotid. junction of anterior communicating artery with anterior cerebral artery. bifurcation of middle cerebral artery.
describe the symptoms & signs of subarachnoid headache
THUNDERCLAP HEADACHE. sudden, devastating occipital headache (I thought I’d been kicked in the head). vomiting, collapse, seizures, coma, neck stiffness, retinal bleeds/papilloedema
give 2 differential diagnoses of subarachnoid haemorrhage
meningitis, migraine, intracerebral bleeds, cortical vein thrombosis
what would you see on CT head in a subarachnoid haemorrhage?
no clear bleed - blood pools in available spaces, showing up white. “star sign” - blood pooled in ventricles appears as white star.
what clinical features would indicate you should avoid doing a lumbar puncture and why?
headache, unilateral pupillary dilatation, vomiting, papilloedema, reduced mental state. these are signs of raised ICP - risk herniation of brain and coning leading to death.
how would the CSF look if you performed a lumbar puncture on a person with subarachnoid haemorrhage?
CSF is bloody early on, then becomes yellow due to bilirubin - finding xanthochromia (yellow CSF) confirms SAH
how would you manage a subarachnoid haemorrhage?
hydrate, aim for systolic BP of 160 in order to maintain cerebral perfusion. nimodipine - CCB, reduces vasospasm. endovascular coiling, surgical clipping, intracranial stents, balloon remodelling.
give 2 possible complications of SAH
rebleeding. cerebral ischaemia due to vasospasm - permanent CNS deficit. hydrocephalus due to blockage of arachnoid granulations.
explain the process behind subdural haemorrhage
bleeding from bridging veins between cortex and venous sinuses - accumulating haematoma between dura and arachnoid - ICP gradually rises - midline structures shifted away from side of clot - eventual tentorial herniation and coning unless treated
who is at risk of subdural haemorrhage?
(those with small brains) - trauma patients, the elderly. those prone to falls (epileptics, alcoholics). those on anticoagulants.
how would a subdural haemorrhage present?
fluctuating consciousness level ± insidious physical/intellectual slowing. sleepiness, personality change, unsteadiness. raised ICP (headache, nausea, vomiting & raised BP), seizures.
what would you see on head CT/MRI of a patient with a subdural haemorrhage?
clot ± midline shift. crescent shaped collection of blood over one hemisphere.
how would you manage a subdural haemorrhage?
Mannitol for ICP. irrigation/evacuation - burr twist drill/burr hole craniostomy. craniotomy.
what causes an extradural haemorrhage?
MIDDLE MENINGEAL ARTERY most common. any tear in dural venous sinus. fractured temporal or parietal bone - causes laceration of middle meningeal artery and vein, typical after trauma to temple just lateral to eye.
what is a common clinical presentation of extradural haemorrhage?
‘lucid interval’ - walks away from road traffic accident seeming fine (no loss of consciousness), then after a few hours/days, there’s a decrease in GCS from rising ICP.
after a lucid interval, what will be the clinical features of an extradural haemorrhage?
increasingly severe headache, vomiting, confusion, fits ± hemiparesis. then - ipsilateral pupil dilates, coma deepens, bilateral weakness develops, deep and irregular breathing (brainstem compression)
how would an extradural haematoma appear on head CT?
round shape, rather than the sickle shape seen in subdural haematoma.
how would an extradural haematoma be treated?
mannitol for ICP. neurosurgery - clot evacuation ± ligation of bleeding vessel
what 2 medical treatments can help reduce the risk of complications in intracranial haemorrhages?
dexamethasone (glucocorticoid) - reduces cerebral oedema, stabilises BBB. nimodipine - CCB, reduces vasospasm
define a seizure, and define epilepsy
seizure = convulsion or transient event caused by a paroxysmal discharge of cerebral neurones. epilepsy = continued tendency to have seizures.
What is the status epilepticus management pathway
- open and secure airway and give 100% oxygen
- IV access and take blood: U&E, LFT, FBC, GLUCOSE, Ca2+, toxicology screen if indicated
- IV bolus to stop seizures - Lorazepam 4mg (or suppository Diazepam), give 2nd dose if no response after 10-20mins
- correct hypotension with fluids
- If seizures continue - start Phenytoin
what do the terms tonic, myoclonic and akinetic mean in terms of seizures?
tonic = intense stiffening of body with no convulsions. myoclonic = isolated muscle jerking (rapid repetitions of this = clonic). akinetic = cessation of movement, falling and loss of consciousness
What are the features of an Aura
Strange feeling in gut, deja vu or strange smells or flashing lights
what may be features of the post-ictal state?
headache, confusion, myalgia, sore tongue. temporary weakness following focal seizure in motor cortex / dysphasia following seizure in temporal lobe.
list 4 causes of epilepsy
idiopathic/familial - 2/3rds! cortical scarring, developmental, space-occupying lesion, stroke, hippocampal sclerosis, vascular malformations, tuberous sclerosis, sarcoidosis, SLE,
list 4 non-epileptic causes of seizures
trauma, stroke, haemorrhage, raised ICP, alcohol/benzodiazepine withdrawal, metabolic disturbance, liver disease, fever. infection - HIV, meningitis, encephalitis, syphilis. drugs - tricyclics, cocaine, tramdol, theophylline
describe the features of a simple partial seizure
awareness unimpaired. focal motor, sensory, autonomic or psychic symptoms. no post-ictal symptoms.
describe the features of a complex partial seizure
impaired awareness. may have simple partial onset (aura). arise from temporal lobe. post-ictal confusion.
what happens in a partial seizure with secondary generalisation?
electrical disturbance that began focally spreads widely causing a secondary generalised seizure - usually convulsive
what occurs in the brain during a primary generalised seizure?
simultaneous onset of electrical discharge throughout cortex with no localised features
describe the features of absence seizures
brief pauses, e.g. stops mid-sentence then carries on - presents in childhood
describe the features of tonic-clonic seizures
loss of consciousness. limbs stiffen (tonic) then jerk (clonic). may have one without the other. post-ictal - confusion, drowsiness.
describe the features of myoclonic seizures
sudden jerk of a limb, face or trunk. patient may be thrown to the ground suddenly, or have a violently disobedient limb.
describe the features of atonic (akinetic) seizures
sudden loss of muscle tone causing a fall, no loss of consciousness
What are the differences with a non-epileptic seizure compared to an epileptic seizure
- non-epileptic seizures are situational
- non-epileptic is longer, closed mouth/eyes during tonic/clonic movements, no incontinence or tongue biting
list some features of a focal seizure that would localise it to the temporal lobe
automatisms - motor phenomena with impaired awareness and no recollection afterwards - lip smacking, chewing, fumbling, fiddling - even complex acts - singing, kissing, driving a car, violence. abdo rising sensation/pain. dysphasia. memory phenomena (deja vu/jamais vu). hippocampal involvement = emotional disturbance. uncal involvement = hallucinations of smell or taste. auditory cortex involvement - auditory hallucinations.
give some features of a focal seizure that would localise it to the frontal lobe
motor - posturing, versive movements of head and eyes, peddling of legs. jacksonian march. motor arrest. subtle behaviour disturbances. dysphasia or speech arrest.
give some features of a focal seizure that would localise it to the parietal lobe
sensory disturbances - tingling, numbness, pain. Motor symptoms if spread to pre-cental gyrus.
give some features of a focal seizure that would localise it to the occipital lobe
visual phenomena - spots, lines, flashes
how would you diagnose an epileptic seizure?
clinically - detailed description of attack from eye witness. EEG - electroencephalogram and CT/MRI.
how would you treat generalised tonic-clonic seizures?
sodium valproate or lamotrigine. 2nd line - carbamazepine or topiramate.
how would you treat tonic, atonic and myoclonic seizures? what should be avoided?
as for tonic-clonic but avoid carbamazepine. so, sodium valproate/lamotrigine, with topiramate as 2nd line.
how would you treat partial seizures ± secondary generalisation?
carbamazepine or lamotrigine - 1st line. Sodium Valproate 2nd line
what is the cardinal Parkinsonism triad comprised of?
bradykinesia (Parkinsonian gait), cogwheel rigidity, resting tremor
explain the pathophysiology of Parkinson’s disease. the presence of what feature in the brain is diagnostic?
degeneration of dopaminergic neurons in the substantia nigra pars compacta, associated with presence of Lewy bodies. causes decrease in striatal dopamine levels leading to cell loss and akinesia.
give 3 non-motor symptoms of Parkinson’s disease
depression, dementia, dribbling, anosmia (reduced sense of smell), hallucinations, constipation, dysphagia, heartburn, urinary difficulties, micrographia.
what one main risk factor for other diseases, is protective in Parkinson’s disease?
smoking
explain what you are likely to observe if you were to ask a Parkinson’s patient to walk up and down for you
stooping, shuffling gait. struggles to start walking. Reduced arm swing. narrow base making falls common. obstacles, doors etc make them freeze and struggle to restart.
what is the typical age of onset of Parkinson’s disease?
65yrs
describe the medical management of Parkinson’s disease
dopamine agonists (Ropinirole, Pramipexole)
MAO-B inhibitor (rasagiline, selegiline)
COMT inhibitors (Entacapone, Tolcapone)
These allow delay of starting L-Dopa.
start levodopa late - becomes ineffective after several years so start late and at a low dose then increase as needed. prescribe with a decarboxylase inhibitor in a combined formation such as Co-careldopa or Co-deneldopa
why can’t Parkinson’s patient just be treated with dopamine?
it cannot cross the blood-brain barrier - levodopa is a precursor of dopamine and is able to cross the BBB and the be converted to dopamine within the brain.
what non-pharmacological treatment options are available for Parkinson’s?
deep brain stimulation, surgical ablation of overactive basal ganglia circuits.
what is Huntington’s chorea?
autosomal dominant, incurable, progressive, neurodegenerative disease.
define chorea
abnormal involuntary movements - brief, abrupt, irregular, unpredictable, non-stereotyped - may appear purposeful - patient appears fidgety/clumsy
describe the features of the prodromal phase of Huntington’s disease
irritability, depression, incoordination - personality changes, self-neglect (doesn’t wash, doesn’t care about work), fidgeting, tic.
what is the underlying pathology of Huntington’s chorea?
Caused by increased CAG repeats on chromosome 4. Leads to cerebral atrophy with loss of GABA and Cholinergic neurones. Results in decreased ACh & GABA synthesis in the striatum. Loss of GABA means decreased inhibition of dopamine release and therefore result in excessive thalamic stimulation and thus excessive movements.
How would you diagnose huntington’s
Genetic testings shows many CAG repeats
MRI might show caudate nucleus atrophy & increased sized of the frontal horns of the lateral ventricles (signs of brain matter destruction)
how would you treat Huntington’s chorea?
nothing will stop progression - symptomatic treatment only. - sulpiride or haloperidol - antipsychotic drug
Benzodiazepines e.g. diazepam - sedative drug
Tetrabenazine - a dopamine depleting agent - considered best antichoreic drug
Antidepressants such as SSRIs
name 3 precipitating factors of a tension headache
stress, sleep deprivation, hunger, eyestrain, anxiety, noise
how might a patient describe the pain of a tension headache?
bilateral, ‘tight band’, non-pulsatile, scalp tenderness.
how would you manage a patient with tension headaches?
reassurance. stress relief. can prescribe NSAIDs, paracetamol or aspirin - watch for analgesic overuse headache
what are the clinical features that affect the eye in cluster headaches?
lacrimation, transient ipsilateral Horner’s (pupil constriction), lid swelling ± ptosis, unilateral eye pain
describe the timeline of cluster headaches
recurrent bouts of the headache a couple of times a day, coming on a few times a month, then disappears for a few months and then returns unexpectedly
describe the pain of a cluster headache
rapid onset excrutiating pain around one eye. strictly unilateral - affects same side each time.
Often nocturnal/early morning - might wake patient from sleep
how would you treat an acute attack of a cluster headache?
100% O2 for 15min via non-rebreathe mask. sumatriptan (SC) - 5HT receptor agonist, acts on serotonin receptors.
what preventatives are available to be used for cluster headaches?
Verapamil (CCB), avoid alcohol, and possibly prednisolone