Phase 2 Flashcards
what does CVA stand for?
cerebrovascular accident
a man having recently undergone surgery on his carotids experiences difficulty swallowing and speaking. his tongue deviates to the right slighlty. Which nerve has been damaged?
right hypoglossal
a man with a 40 year pack history presents with a 4 week history of a hoarse voice. Which nerve is most likely to have been damaged?
recurrent laryngeal
where does the anterior and lateral coricospinal tracts decussate?
anterior corticospinal tract decussates at the level it exits the spine
lateral corticospinal tract decussates at the medulla pyramids
what is paraplegia?
loss of motor and sensory function of the lower limbs due to a spinal cord injury
what are the key features of a TIA?
subacute onset of CNS focal phenomena due to a temporary occlusion of part of the cerebral circulation lasting for less than 24 hours
what is amaurosis fugax?
the sudden loss of vision in one eye- caused by an infarct int the retinal artery
where is the thromobus likely to have arised from if the patient presents with contralateral weakness, dysphagia and homonomos hemaiopia?
anterior ciruclation of the cerebra has been effected- usually from the carotids
if a patient presents with vomiting, chocking, hemiplegic sensory loss, tinnitus which area of the cerebral ciruclation is likely to have been occluded?
posterior circulation
if there is temporary occlusion to the posterior circulation, where is the thrombi likeli to have arisen from?
verterbrobasilar system
in huntingtons chorea which areas of the brain are affected by axonal loss?
caudate nucleus
basal ganglia
what is the name of the type of stroke which results in small infarcts around the basal ganglia and internal capsule?
lacuna infarct
what is papilloedema
swelling of the optic disc
which type of receptors do the antibodies in Myasthenia Gravis attack?
nicotinic Ach receptors on the post synaptic neurone
which muscles does Myasthenia gravis commonly affect>
extra-ocular, bulbar, face and neck, limbs (proximal)
what investigations would you do if suspecting MG
Tensilon test: Administer edrophonium (achesterase inhibitor) and observe if the symptoms improve- need to have atropine to hand due to risk of bradycardia.
CT thymus, nerve conduction studies
how does a subdural haemorrhage present on CT?
concave / crescent shaped (tends to progress more slowly, but can be acute)
what are 4 bedside tests you can do to asses a subarachnoid haemorrhage?
- look for papilloedema (swelling of the optic discs)
- blood pressure- generally increased
- glasgow coma scale- consicousness
- pulse and resp rates
describe the typical appearance of a subarachnoid haemorrhage
sudden onset thundercalp headache, photophobia, neck stiffness.
what is the first line investigation if you suspect a SAH?
CT scan
how might a SAH appear on a ECG?
prolongued QT, dysarthrithmias and ST elevation
what score would you use to classify the severity of a subarachnoid haemorrhage?
Hunt and Hess score
define a seizure
a paroxymal event in which changes in behaviour sensation or cognition are affected by excessive hypersynchronous neuronal discharges in the brain
define epilepsy
the recurrent tendendy to seizures
what is staus epilepticus?
a seizure which lasts longer than 30 minutes
name 8 causes of epilepsy
- idiopathic
- cortical scarring
- tumours
- Stroke
- SLE
- fever/sepsis
- alcohol withdrawl
- raised ICP
what is the difference between a simple partial seizure and a complex partial seizure?
Simple partial seizure= the patient is aware throughout the seizure; there is no post-ictal symptoms
A complex partial seizure= awareness is impaired; most commonly arise in the temporal lobe
name 4 different types of primary generalised seizures
- absent seizure- brief pause mid-sentence then continues
- tonic-clonic; limbs stiffen then jerk, and there is often post-ictal symptoms
- myoclonic: sudden jerk of the limb or face or hand
- atonic: patient loses all muscle tone and falls to the ground.
a patient experiencing a seizure presents with kicking of the legs, and versive movements of the head and eyes- what part of the brain is the seizure likely to originate from?
frontal lobe
a patient experiences tingling and pins and needles (and any other sensory feature) in their fingertips prior to their seizures- which part of the brain is it likely to originate from?
parietal lobe
the patient see’s stars and flashes of light prior to a seizure- which lobe is the seizure likely to arise from?
occipital
name 4 features which you would expect a patient to experience if their seizure began in the temporal lobe
De ja vu aura
dysphagia
automatisms- lip smacking, grabbing, chewing
emotional disturbance- sudden fear, crying, terror
auditory hallucinations- eg hearing music
how do you diagnose epilepsy?
MRI/CT to exclude alternative causes
need to have had 2 unprovoked seizures to have a diagnosis
when are epilepsy patients allowed to drive again?
when they have been 1 year seizure free
what are the side effects of Valproate? VALPROATE
VALPROATE Appetite increases Liver failure Pancreatitis Reversible hair loss Oedema Ataxia Teratogenicity, tremor Encephalopathy
why do drugs which block the neuromuscular receptors not have central side effects>
they are not lipid soluble and therefore cannot pass the blood:brain barrier
what is the treatment for schizophrenia?
dopamine
name 2 side effects of anti achetylcholinesterase inhibitors
dry mouth
urinary retention
what drug do you need to give with L-dopa and why?
Carpidopa; it inhibits dopa decarboxylase, preventing L-dopa from being converted into dopamine in the peripherise
name a side effect of carbamazepine
hyponatraemia
how do benzodiazepines work?
they are allosteric modulators, enhancing the binding of GABA to the GABA-A receptor
how do barbituates work?
they modulate the Cl- channel permeability enabling hyperpolarisation
what is multiple sclerosis
a relapsing and remitting chronic inflammatory disorder due to multiple plaques of demyelination within the CNS. require 2 or more CNS lesions disseminated in time and space. More common away from equator and in female caucasians
name 3 cardinal features of MS and their symptoms and signs
optic neuropathy; blurring in one eye, mild occular pain- affecting the trigeminal nerve
Brainstem demylination- facial numbness, dysphagia,
Spinal cord lesions- urinary incontinence, sexual dysfunction, spastic paraparesis
what is urcoffs phenomenon and what condition is it typically seen in?
symptoms and signs of MS are worse on a hot day or after exercise- heat slows the conduction in nerve fibres.
name 2 other types of MS other than relapsing and remitting
primary progressive- the illness gets worse progressively without any epidoses of marked improvement.
Secondary progressive- intitially starts relapsing and remitting but then becomes continuous without marked improvement
state 2 histological changes may be observed in an active MS lesion
demyelination, variable oligodendrocytes loss, hypercellular plaque edge due to infiltration of tissues with inflammatory cells- mainly macrophages
what investigations would you do for MS?
MRI of brain and spinal cord- typical lesions are multifocal
Lumbar puncture: may see oligoclonal bands of IgG in the CSF
what is the treatment for MS?
acute relapse: methyprednisolone
Maintenance: beta interferon or Nataliluzab if severe
what is rehabilitation?
this is the changes that can be made to help the person live with their disease- about setting attainable goals, and providing support for them to reach these goals.
name an anti-spasticity drug which may help with symptoms of MS
baclofen
name the organism commonly causing infection which 1-3 weeks later presents with acute paralysis (guillian barre syndrome)
CMV or campylobacter pylori
how does guillian barre syndrome commonly present?
pain, tingling and numbness, progressive muscle weakness. Temporary progressive paralysis of the legs-arms-face-respiratory muscles!!!
give 4 signs of Guillian barre syndrome
- abscent reflexes
- hypotonia
- autonomic dysfunction- arrhythmias, reduced sweating and heat tolerance
- altered sensation- paraesthesia
which parts of the brain are affected the most in parkinsons?
substantia niagra and basal ganglia
which neurones are lose in parkinsons disease?
loss of the nigrostriatal cells
name the 2 protiens often seen within the eosinophilic aggregations in the pars compacta of the substantia niagra
ubiquitin and alpha synuclein
name 3 key symptoms of parkinsons disease
tremor, rigidity and Akinesia
handwriting becomes very small, pill rolling tremour at rest decreasing with action. Cogwheel rigidity, difficulty initiating movements, slurring dyarthria, depression, postural instability
name 4 signs of parkinsons disease
slow shuffling gait, stooping appearance, poor arm swing. Urinary difficulties, dysphagia, dribbling, lead pipe rigidity, difficulty initiating movements
name 2 treatments of parkinsons disease apart from L-dopa
Carpidopa (dopadecarboxylase inhibitor- needs to be given with L-dopa to inhibit conversion to dopamine in the peripheries)
MOAB inhibitor- Selegiline
Dopamine agonist- Ropinirole
which part of the brain shows marked axonal loss in huntingtons chorea?
caudate nucleus, putamen and basal ganglia
what is the meaning of chorea?
dance like jerky quasi-purposive movements flitting around the body
name 4 clinical features of huntingtons chorea
jerky involuntary movements- these are relentless and progressive. early onset behavioural changes and irritability progressing to dementia. Dyarthria and dysphagia are also common.
what is the pathology behind huntingtons Chorea?
There is a mutation in the huntingtin gene on chromosome 4- shows variable CAG (cysteine, adenosine, guanine) base sequence repeats- the more repeats in the gene the earlier the onset on huntingtons. It causes axonal degeneration and atrophy in the caudate nucleus, putamen and basal ganglia. They end up with aggregations of dompaine within the synapses-stimulation-causing these jerky uncontrollable movements.
what is the treatment of Huntingtons chorea
treatment does not prevent progression it is only symptomatic , domamine antagoinst- Terabenazine
what is the prognosis of huntingtons Chorea after diagnosis?
death within 10-20 years
name 4 complications of a SAH
- rebleeding- death
- cerebral ischcaemia- due to vasospasm- permanent CNS deficit
- hydrocephalus- due to blockage of the arachnoid granulations (resorb CSF)
- hyponatraemia
name 2 findings you may see in a lumbar puncture after a SAH
- xanthochromic fluid- yellow looking due to the break down in haemoglobin after 12 hours of SAH
- mononuclear polycytosis secondary do chemical meningitis caused by the degradation products in subarachnoid blood.
why do you need to take 3 samples of LP after a SAH
one for virology, one for microscopy and one for biochemistry
why do you need to wait 12 hours after SAH before undertaking LP?
- to prevent the risk of cerebral herniation through the foramen magnum when LP decreased the ICP
- xanthochromic fluid is most commonly found 12 hours after SAH, making the sample collected more sensitive to confirm whether there was a SAH or not.
why might patients experience a sentinel headache prior to the SAH?
perhaps due to a small warning leak from the offending aneurysm
what is the pathophysiology of giant cell arteritis?
inflammatory granulomatous arteritis of the large cerebral arteries
how might giant cell arteritis present?
jaw claudication
tenderness of the scalp, severe headaches, sudden painless loss of vision, malaise, tireness and fever
what investigations might you do for giant cell arteritis?
FBC: normocytic anaemia, ESR raised, temporal artery biopsy
what will you see on a temporal artery biopsy in giant cell arteritis?
intimal hypertrophy, inflammation of the intima and sub intima, breaking up the elastic lamina, giant cells, lymphocytes and plasma cells in the elastic lamina.
what is the treatment for giant cell arteritis?
prednisolone
name a secondary cause of trigeminal neuralgia?
compression by anomalous or aneurysmal intracranial vessels/a tumour, MS, causing demyelination.
how might trigeminal neuralgia present?
knife like or electric shock like pain lasting seconds in the distribution of the 5th CN. Pain when washing, shaving or a cold wind brushing the face.
