Neuro conditions Flashcards
Ischaemic stroke Cause Risk Most common sites, symptoms ass. Diagnosis Treatment
Cause: a) endothelial cell dysfunction -> atherosclerosis -> fibrous cap lost, becomes thrombogenic and can block artery within mins. b) embolism - clot breaks off - from heart, blood stagnates (eg due to A.Fib) and clot formed in L atrium is pumped to brain.
Risk: male. black.asian, hypertension, past TIA, A.fib, increasing age, heart disease, alcohol, contraceptive pill, hypercholesterolaemia…
90% are anterior circulation strokes (carotid artery: ACA,MCA,PCA, affect cortex and top of brain), 10% posterior (basilar/vertebral artery, affect cerebellum and brainstem)
ACA - affects legs, trunk with weakness
MCA - contralateral arm/leg weakness, hemianopia, facial droop, dysphasia
PCA - visual processing affected
For posterior circulation strokes, many present non-specifically as vertigo/nausea/vomiting, or motor deficits, dysarthria and speak impediment. They are often more catastrophic, locked in syndrome more likely.
Diagnosis: clinical, as speed is crucial. CT scan is done to rule out haemorrhagic stroke which would contra-indicate thrombolysis.
Treat:
1. If within 4.5hrs onset symptoms, IV alteplase for thrombolysis.
2. Risk management: aspirin + clopidrogrel
Statins, warfarin/NOACs if a.fib, anti-hypertensives.
Haemorrhagic stroke Cause? Risk? Diagnosis Treat
Account for 17% strokes, caused by CNS bleed due to:
trauma, carotid artery dissection (neck manipulation - younger people), anticoagulation, aneurysm ruptre, thrombolysis, subarachnoid haemorrhage.
Risk: male. black.asian, hypertension, past TIA, A.fib, increasing age, heart disease, alcohol, contraceptive pill, hypercholesterolaemia…
Distinguish from ischaemic: low GCS, signs of raised ICP (headache, coma). Urgent CT to identify bleed. Assume if on anti-coags
Treat:
Reverse anticoags (vit K for warfarin, NOACs are not reversible)
Control hypertension
Decompress ICP - manually, mannitol diuretic
May need surgery
TIA - what? Cause Symptoms Diagnosis Treatment
Transient ischaemic attack
Sudden loss of neurological function that lasts mins (/less than 24 hrs) and resolves with complete recovery and no evidence of infarct on imaging
Cause: atherothromboembolism from carotid. Cardioembolism forms microemboli (eg from MI, AF, valve disease). Hyperviscosity of blood (due to polycythaemia, myeloma, sickle cell anaemia).
Symptoms:
90% ant. circulation, contralateral leg/arm weakness, hemiparesis, sensory deficit, dysphasia, amaurosis fugax.
Post circulation = nausea, vertigo, paresis, speech impediment.
Diagnosis:
clinical - impossible to dist. from stroke until full recovery. ABCD2 score used to measure severity:
Age
Blood pressure
Clinical presentation
Duration symptoms
Diabetes mellitus
Score out of 7, 6 predicts stroke - refer to specialist!
Treat:
Immediate aspirin + dipyridamole antiplatelet for 2 wks, clopidogrel long term.
Risk manage: statins, anti-hypertensive, anticoag, diet, smoking
Parkinson's Disease who? Cause? Diagnose Presentation Treatment
Neurones of the substantia nigra degenerate causing less dopamine to be produced. Dopamine stimulates the cerebral cortex to produce movement.
M:F 2:1. 3% of over 65s. Most idiopathic, some genetic (parkin gene, alpha synuclein) some environment (toxns - pesticides, MPTP ilicit drug).
Diagnosis is clinical. Substantia nigra diminished + presence of Lewy bodies.
DATScan shows less dopamine going to striatum, MRI shows atrophy.
Presentation:
Asymmetrical.
1. Tremor (resting)
2. Rigidity (stiffness, stooped posture, reduced armswing, expressionless face)
3. Bradykinesia (slow to initiate movement)/hypokinesia, akinesia
Shuffling gait.
Before motor symptoms, often have depression, dementia, sleep dist., urgency, aches/pains, loss of sense of smell…
Treatment - symptomatic
Levadopa + decarboxylase inhibitor (to prevent peripheral conversion of L-dopa to dopamine, so reducing side effects)
+ physio
However, meds have reduced efficacy over time and random stiffness, painful fixed muscles and hyperkinetic overshooting can occur if long term use.
Epilepsy/epileptic seizures What? Cause Types and subcategories Symptoms - for focal seizures, what symptoms are ass. with specific lobes of the brain? Diagnose Treat Emergency?
Recurrent, unprovoked episodes of epileptic seizures (excessive, hypersynchonous neuronal discharges) - at least 2 more than 24hrs apart.
2/3 idiopathic, can be structural abnormality eg tumour/brain injury, infection, drug use
Partial/focal: 1 hemisphere/lobe affected. Simple = remains conscious, complex = impaired/loss consciousness.
Generalised: both hemispheres affected. Tonic- clonic: rigid followed by convulsions. Can also be atonic (floppy), myoclonic (muscle twitch) or absense seizure (‘spaced out’).
Frontal lobe: Jacksonian march (seizure progresses along motor homunculus), post-ictal Todd’s paresis (in arms/legs)
Temporal: aura, automatisms (chewing/lip smacking)
Parietal: sensory disturbance
Occipital: visual phenomena eg flashes
Diagnose:
By definition (2+ unprovoked seizures).
EEG, MRI, CT can identify abnormalities that are causing seizure.
Treat:
Acutely, for long/repeated generalised seizures: diazepam
For generalised tonic-clonic: sodium volproate
Focal: carbamazepine
1/3 epileptics are resistant to drug treatment.
Neurosurgical resection if tumour/hippocampal sclerosis. Vagal nerve stimulation can help.
Emergency: status epilepticus = continuous seizures, risk cardioresp failure, caused by stopping meds/alcohol abuse/poor compliance. Sudden Unexpected Death Epilepsy more likely in uncontrolled epilepsy.
Multiple Sclerosis What is it? Risk? Symptoms based on common locations of sclera Diagnosis Treatment
Chronic, autoimmune (T cell mediated), inflammatory demyelinating disease of the CNS.
T lymphocytes attack myelin leaving perivenular sclera/plaques, which slow/block signal conduction. Remission then occurs where remyelination is possible, however over time axonal damage occurs - symptoms progressively worse with each attack (= relapsing remitting - some cases are progressive without relapse).
F>M, 20-40yo
HLA DR2 gene
Ass. with EBV infection in childhood
Ass. with Vit D deficiency
Symptoms:
Depend on location of plaques - commonly….
Charcot’s neurological triad
1. Optic nerves: optic neuritis: unilateral loss/blurred/double/painful vision
2. Brainstem: dysarthria, dysphagia,
3. Motor pathways - cerebellar, spinal cord: intention tremor, ataxia, muscle weakness/spasm
+ plaques in sensory pathways = numbness, parasthesia, Lhermitte’s sign: shooting back pain on flexing neck, plaques in autonomic NS = sexual dysfunction, incontinence
Diagnosis:
“Symptoms are spread over space and time” - 2+ symptoms of CNS lesions, in different locations, with bouts/remission.
Gold standard: MRI shows white matter plaques
Treat: early and agressively
IV methyl prednisolone to shorten acute relapse
anti-inflam cytokines Interferon 1beta
Natalizumab disease modifying
Symptomatic: - BACLOFEN anti-spasticity
Aggressive - stem cell transplant.
Life-expectancy for people with MS is 5-10 years below average - they often die from aspiration pneumonia due to their dysphagia and swallowing difficulties
Subarachnoid haemorrhage cause risk symptoms diagnose treat
Bleed into the subarachnoid space between arachnoid mater and pia mater, causing tissue ischaemia and rapid raised ICP.
Cause:
Rupture of berry aneurysm
Atriovenous malformation (fistula in the brain)
Risk:
Hypertension, smoking, family history, known aneurysm/predispotition to aneurysm: polycystic kidney disease, coarction aorta…
Symptoms:
Sudden onset, severe occipital ‘thunderclap’ headache
Followed by drowsy/vomiting/collapse/coma/seizure
Diagnose:
CT head shows star shaped lesion in >90%, if still suspected but not visible CSF (lumbar puncture) contains xanthrochromin from Hb breakdown
Treat:
Ca2+ blocker to prevent vasospasm (vasoconstriction) which could cause ischaemia: nimodipine
IV fluids to perfuse cerebrum
Coiling(catheter through groin)/clipping (cut above eyebrown) of aneurysm
Subdural haematoma cause risk presentation diagnosis treatment
Trauma to head -> bridging veins bleed, solid swelling of clotted blood collects between dura and arachnoid mater. Lysis draws in water, it grows, gradually increasing ICP. Can herniate through foramen magnum Risk: Brain atrophy - the elderly, alcoholics Traumatic head injury Anticoagulation Presents: often weeks/months after trauma! Slower if elderly! signs of raised ICP = vomiting, drowsy, seizure, compensatory raised BP fluctuating consciousness personality change Diagnose: CT shows sickle shaped blood collection in 1 hemisphere, shifts midline to one side Treat: neurosurgeon for evacuation of haematoma IV mannitol diuretic to decrease ICP address cause of trauma
Extradural haemorrhage cause presentation diagnosis treatment
Traumatic head injury (usually to temple) fractures temporal/parietal bone, leading to laceration of the middle meningeal artery. Blood accumulates rapidly between bone and dura, compressing brain structures, coning (herniating via foramen magnum).
Classic presentation:
Post traumatic loss of consciousness, followed by lucid interval which can last hrs/days.
Then altered consciousness - signs raised ICP, decreased GCS, progresses to coma as brain compressed. Can lead to death due to respiratory arrest
Diagnosis:
CT head shows hyperdense haematoma adjacent to skull
XR may show fracture
Treat:
mannitol for ICP
neurosurgeon: evacuation of clot, BV ligation
Intubation, ventilation to support airways
Bacterial Meningitis causes - risk? symptoms diagnosis treatment
In neonates…
Group B streptococcus, E.coli, Listeria monocytogenes
Children + teens…
Neisseria meningitidis, streptococcus pneumoniae
Adults, elderly…
Strep pneumoniae, listeria monocytogenes (elderly)
Symptoms:
classic triad - fever, headache, stiff neck
photophobia
If meningococcal septicaemia, purpuric/petechial rash + signs of sepsis
Diagnosis:
Lumbar puncture shows cloudy CSF
Treat:
IV cefotaxime
add amoxicillin for elderly/immunocompromised to cover listeria monocytogenes
Motor neurone disease
what?
symptoms?
signs - suspect in…
Degenerative disease characterised by loss of neurones in the motor cortex, cranial nerve nuclei and anterior horn cells of the lateral corticospiinal tract. (UMN decussates in medulla, synapses in ant horn with LMN -> skeletal muscle)
Symptoms
Both UMN and LMN affected, but no sensory loss.
LMN signs… decreased muscle tone, muscle wasting, fasciculation
UMN signs… brisk reflex, spasticity, extensor plantar response.
Weakness and atrophy spreads 2 all 4 extremities, trunk, bulbar muscles - bulbar palsy (impaired function of CN9,10,11,12 - leads to dysphagia, dysarthria).
May have emotional lability
Signs:
over 40yrs with…
stumbling spastic gait
foot drop +/- proximal myopathy
weak grip and shoulder abduction
aspiration pneumonia
Diagnosis is based on exclusion other conditions, scans and nerve activity tests.
Treat:
- antiglutanergic : riluzole
- prevent drooling due to bulbar palsy: amitriptyline
- spasms: baclofen
- + analgesia, specialist support, ventilation
Encephalitis common cause presentation investigate treat
= inflammation of the brain
causes:
usually viral - herpes simplex, varicella zoster (measles mumps rubella EBV HIV…)
other - japanese encephalitis, rabies - travel
Non-infective: autoimmune, paraneoplastic
Presents:
hours - days of flu-like symptoms, then altered GCS
Triad = fever + headache + altered mental state
Investigate:
MRI head
lumbar puncture
HIV test
Treat:
supportive
acyclovir if HSV or VZV
CNS cancer cause red flag symptoms diagnosis treatment
most commonly secondary tumours from lung/breast
Primary - named according to cell type, region
meningioma, germ cell, sellar, neuroepithelial/glioma - astrocytic most common, oligodendroglioma, schwannoma, lymphoma
Graded using morphology + molecular genetic features from 1 to 4, TNM not used.
Cause:
mainly idiopathic
ionising radiation, fam hist, immunosuppression
Symptoms depend on tumour type, grade, site
Red flag:
- headache with features raised ICP (focal neurology, papilloedema)
- new focal seizure
- hist other cancer
- progressing focal neurology
Diagnose
Low grade often incidental finding
MRI gold standard, brain biopsy for staging
Treatment:
curative resection possible for grade 1, best if pt awake, followed by radio + chemo
symptomatic treatment for high grade
steroids for oedema, surgery to relieve ICP, radio, chemo
