neuro anki 2 Flashcards
What is the most common cause of a SAH
Head injury
What would you expect to see on a NCCT head of a patient with an SAH?
Hyperdense blood in basal cisterns/sulci
What would be seen on a LP of a patient with a SAH?
Xanthochromia: breakdown of RBC
What is the immediate treatment for a patient with a TIA?
Immediate antithrombotic therapy: aspirin 300mg unless CI
What is the most common blood vessel implicated in an extradural haemorrhage?
Middle meningeal artery-> thin skull at pterion
Usually arterial
What patient group is most commonly affected by an extradural haematoma?
Young patients with head injury-sports etc
What proportion of patients will have bilateral subdural haemorrhages?
15% adults
80% infants
Why are alcoholics and infants and the elderly more at risk of a subdural haemorrhage?
Brain atrophy
fragile/taut bridging veins
What kind of vessels are implicated in a subdural haemorrhage?
Rupture of bridging veins within subdural space
What proportion of strokes are ischaemic?
85%
15% haemorrhagic
What scoring system in used for those with a potential ischamic stroke?
ROSIER score->0 makes a stroke likely
When is thrombolysis contraindicated in a patient with an ischaemic stroke?
Previous haemorrhage
GI bleed
Recent surgery
Hypertension
Increased INR
When should thrombectomy be considered as a treatment for an acute ischaemic stroke?
If confirmed occlusion of proximal anterior circulation on CTA or MRA (with IV alteplase if <4.5 hours, on its own if 6-24 hours)
Consider: >24 hours: confirmed occlusion of proximal posterior circulation on MRA/CTA/potential to salvage brain tissue
What part of the brain is supplied by the posterior cerebral artery?
Posterior cerebral cortex:Occipital lobe, thalamus etc
What symptoms would you expect with a middle cerebral artery infarction?
Contralateral loss of sensation and motor control to face and UPPER limbs
Broca’s aphasia
What symptoms would you expect with an anterior cerebral artery infarction?
Contralateral loss of sensation and motor control to lower body
What symptoms would you expect with a posterior cerebral artery infarction?
Contralateral homonymous hemianopia
What symptoms would you expect with a basilar artery infarction?
Locked in syndrome-> bilateral loss of corticospinal tracts
What symptoms would you expect with an anterior inferior cerebellar artery infarction?
Contralateral loss of pain and temperature sensation
Lateral pontine syndrome
Ipsilateral:-CN3 palsy
-Vertigo/nystagmus/deafness-
Poor coordination/tone/balance
What vessels are implicated in Weber’s syndrome?
Upper basilar and posterior cerebral
What vessel is involved in a Wallenberg stroke?
Posterior inferior cerebellar artery
What is Horner’s syndrome?
Ptosis
Miosis
Anhidrosis
Damage to sympathetic nerve supply to the eye
What vessels are implicated in a total anterior circulation stroke?
Middle cerebral/anterior cerebral-> large cortical
What vessels are implicated in a partial anterior circulation stroke?
Only part of anterior circulation-> ACA/MCA
What parts of the brain are affected in a posterior circulation stroke?
Cortical
Cerebellum
Brainstem
Vertebrobasilar arteries
What will a CN3 palsy result in?
Occulomotor
Ptosis
‘down and out’ eye
Dilated fixed pupil
What will a CN4 palsy result in?
Trochlear
Defective downward gaze-> vertical diplopia
What is encephalitis?
Inflammation of the brain parenchyma
What part of the brain is most commonly affected by HSV1 encephalitis?
Temporal and inferior frontal lobes
What is meningitis?
Inflammation of the meninges (dura, arachnoid, pia)
Can be infective or non infective
What is the most common fungal cause of meningitis?
Cryptococcus neoformans
What is Waterhouse friedrichsen syndrome?
Adrenal insufficiency caused by intra-abdominal haemorrhage from DIC
Which bacteria is most likley to result in DIC and what does it look like under microbiology?
N.meningitidis
Gram egative diplococcus
What is neurofibromatosis?
Genetic condiiton that causes nerve tumours(neuromas) to develop in the nervous system
Benign but can cause neurological/structural problems
What is neurofibromatosis type 1 also called?
Von Recklinghausen’s syndrome
What is the inheritance pattern of neurofibromatosis type 2
Autosomal dominant
What is the main symptom/complication of neurofibromatosis type 2?
Bilateral acoustic neuromas
What is giant cell arteritis/temporal arteritis?
Vasculitis of unknown cause that affects medium-large sized vessel arteries, especially at the temples
Overlap with PMR
What would be seen on fundoscopy in a patient with giant cell arteritis?
Swollen pale disc and blurred margins
Why is there no forehead sparing in Bell’s palsy?
LMN palsy: affects facial nerve after its entered the brainstem
Contrast stroke: innervation from both hemispheres of the brain
When should patients with Bell’s palsy be referred to specialists?
Urgent ENT referral if no improvement after 3 weeks
Plastic surgery referral if long standing weakness(month)
What is essential tremore?
Common movement disorder characterised by a rhythmic postural or kinetic tremor primarily affecting the upper extremities
What is myasthenia gravis?
Autoimmune disease-> AChR(nicotinic ACH receptor antibodies)
What is the ice pack test for myasthenia gravis?
Measure degree of ptosis
Apply ice pack for a few minutes
Measure degreee of ptosis again
Positive if >2mm improvement
What is the edrophonium test for myasthenia gravis?
Administer small amount of edrophonium chloride(Tensilon): See effects
If rapid, transient increase in muscle strength; indicative of diagnosis
What is Meniere’s disease?
Inner ear disorder caused by increased fluid pressure in the endolymphatic spaces of the membranous labyrinth
What is trigeminal neuralgia?
Chronic pain condition characterised by severe sudden and brief bouts of shooting/stabbing pain that follow the distribution of one or more divisions of the trigeminal nerve, affecting the patients facial region
What is Guillain Barre syndrome?
Ascending inflammatory demyelinating polyneuropathy->acute onset of bilateral and roughly symmetric limb weakness
What might be seen on an LP of a patient with Guillain barre?
albuminocytological dissociation
Increased albumin without corresponding increase in white blood cells
What is the prognosis of Guillain Barre syndrome
Mostly full recovery
Can have residual weakness or fatigue
What is Miller Fisher syndrome?
Variant of GBS
Ophthalmoplegia, areflexia and ataxi(eye muscles affected first-descending paralysis)
Anti GQ1b antibodies in 90%
What is Huntington’s disease?
Genetic disorder that causes progressive breakdown of nerve cells in brain leading to motor, cognitive and psychiatric abnormalitis
What is meant by ‘anticipation’ with regards to genetics in Huntington’s disease
Number of CAG repeats directly correlated with disease severity and age of onset
Symptoms present earlier in excessive generations due to increase in number of repeats
What is the prognosis for Huntington’s Disease?
Decline in physical and cognitive abilities
Death usually due to complications related to physical decline like pneumonia
Suicide second mc cause of death
What is the new seizure classification based on?
Where seizure started in the brain
Level of awareness during seizure
Other features
What is Jacksonian March?
Type of focal motor seizure that progressively ‘marches’ through adjacent areas of brain
Typically starts in hands and face then speards to other muscle group(hands, arm, shoulder, face)
Seizure may progress into generalised tonic clonic seizure
Often associated with structural brain lesions
What is Todd’s paresis?
Temporary postictal weakness or paralysis following a seizure
Usually lasts minutes to hours but can last up to 48 hours
Usually unilateral but can be bilateral
Transient so patient will recover following resolution of postictal state
Which medication might worsen absence seizures?
Carbamazepine
What is sodium valproate associated with when used in pregnancy?
Neural tube defects
What is phenytoin associated with when used in pregnancy?
Cleft palate
Which anti-epileptic is generally considered the least teratogenic?
Carbamazepine
Which antiepileptics are safe for use when breastfeeding?
Generally most of them except for barbituates(ohenobarbitol etc)
When are patients usually commenced on AEDs afer having a seizure?
After the 2nd seizure
What is status epilepticus?
Seizure lasting >5 minutes OR
Multiple seizures over 5 minutes without fully regaining consciousness between
What is normal pressure hydrocephalus?
Neurological disorder where CSF accumulates in the ventricles causing them to enlarge
What is the most common subtype of diabetic peripheral neuropathy
Distal symmetrical sensory neuropathy
Which joints are most commonly affected in charcot arthropathy?
Tarsometatarsal joints
Can involve any joint in a limb that has lost sensation due to neuropathy
What signs might you see with lesions to the cerebellar vermis?
Truncal ataxia and gait instability with fewer cerebellar signs in the limbs
What signs might you see woth a lesion in the cerebellar hemisphere?
Signs in ipsilateral limb
What is Parkinson’s disease?
Chronic progressive neurological condition
What is the triad of symptoms associated with Parkinson’s disease?
Tremor
Muscle rigidity
Bradykinesia
What would prompt suspicion of multiple system atrophy over Parkinson’s disease?
Early/prominent autonomic dysfunction
Degree of cerebellar involvement
What would prompt consideration of lewy body dementia vs Parkinson’s disease
Dementia occurs <1yr after onset of motor sx/come first
Early and prominent cognitive dysfunction/hallucinations
What is the 1st line treatment for Parkinson’s disease
Levodopa
What might be used to treat the peripheral side effects such as n+v in patients on levodopa?
Domperidone
What is the end of dose effect in levodopa therapy?
AKA wearing off effect
Medications effect wears off as next dose is due so symptoms get worse
What is the on and off phenomenon in patients with levodopa therapy
‘On’ periods where medication works well and ‘off’ periods where medication doesn’t work as well
As it progresses, duration of ‘on’ periods can shorten and ‘off’ periods becomme more frequent
What is hypoxic-ischaemic encephalopathy?
Neurological condition resulting form inadequate cerebral oxygen supply
What organisms most frequently cause brain abscesses?
Streptococcus-mc
Staph
Gram negatives
TBFungi
Parasites
Where do malingnat lesiosn in the brain most commonly come from?
Breast
Lung
Melanoma primaries
What would be seen on histology of a patient with a glioblastoma multiforme?
Pleomorphic tumour cells border necrotic areas
Where are meningiomas most commonly found?
Falx cerebri
Superior sagittal sinus
Convesity
Skull base
What would be seen on histology of a patient with a meningioma?
Spindle cells in concentric whorls and calcified psammoma bodies
What might be seen on histology of a vestibular schwannoma?
Antoni A or B patterns seen
Verocay bodies(acellular areas surrounded by nucelar palisades)
What would be seen on hitology in a pilocytic astrocytoma?
Rosenthal fibres(corkscrew eosinophilic bundle)
What would be seen on histology in a medulloblastoma?
Small, blue cells
Rosette pattern of cells with many mitotic figures
Where is an ependymoma most commonly seen?
4th ventricle
What might ependymoma cause?
Hydrocephalus
What would be seen on histology of a patient with an ependymoma?
Perivascular pseudorosettes
What might be seen on histology of a patient with an oligodendroma?
Calcifications with a ‘fried egg’ appearrance
What would be seen on histology of a haemangioblastoma?
Foam cells and high vascularity
What might be seen on histology of a patient with craniopharyngioma?
Derived from remnants of Rathke’s pouch
What is herpes zoster ophthalmicus?
Serious, vision threatening infection caused byt the reactivation of the varicella zoster virus within the ophthalmic division of the trigeminal nerve
What is shingles?
Reactivation of the varicella zoster virus which can lie dormant in the nerve ganglia following primary infection(chickenpox)
When iss thee shingles vaccine advised?
One off vaccine advised for those in tehir 70s
What is idiopathic intracranial hypertension?
AKA psudotumour cerebri/benign intracranial hypertension
Increased intracranial pressure without any clear cause evident on neuroimaging and other investigations
Which medications are associated with idiopathic intracranial hypertension?
COCP
Tetracyclines
Retinoids
Lithium
Thyroxine
Nitrofurantoin
What is narcolespy?
Neurological condiiton that distrubs the sleep wake cycles
Excessive sleepiness during daytime and may also suddnely fall asleep during activities-early onset of REM sleep
What is narcolepsy associated with low levels of?
Orexin(hypocretin)-> protein responsible for controlling appetite and sleep patterns
What is motor neurone disease?
Group of progressive neurological disorders that destroy motor neurones: the cells that control voluntary muscle activity
What signs/symptoms would you NOT expect to find in a patient with MND?
No sensory signs/symptoms
Doesn’t affect external ocular muscles
No cerebellar signs
Eye and sphincter dysfunction usually not present until late
What is myopathy?
Condition affecting skeletal muscles
What is degenerative cervical myelopathy?
Spinal cord dysfunction from compression in the neck
What is Hoffman’s sign?
Used for cervical myelopathy
Flick one finger on a patients hand->positive if reflex twitching of other fingers on same hand
What is degenerative cervical myelopathy sometimes misdiagnosed as?
Carpal tunnel
What symptoms will a lesion in the dorsal column cause?
Loss of vibraiton and proprioception
What symptoms will a lesion in the spinothalamic tract cause?
Pain, sensation and temperature
What symptoms will a lesion in the central cord cause?
Flaccid paralysis of the upper limbs
What is the anal sphincter innervated by?
S2,3,4
What is sub-acute combined degeneration of the spinal cord?
Degeneration of the dorsal columns, lateral corticospinal tracts and spinocerebellar tracts associated with vitamin B12 deficiency
What sensation is preserved in sub-acute combined degeneration of the spinal cord
Pain and temperature
What is the prognosis like for Duchenne and Becker’s muscular dystrophy
Most children can’t walk by age 12
Typicaly survive to age 25-30yrs
Better for Becker’s: live into 30s
When should topirimate not be used for migrain prophylaxis and why?
Avoid in women of childbearing age
Teratogenic and can reduce effectiveness of hormonal contraceptives
What is the problem with regular use of acute migraine medications?
If used>10-15 days/month-> medication overuse headache
What is needed to be monitored if treating a patient with verapamil?
ECG to check cardiac function
What is the most common form of dural venous sinus thrombosis
Superior sagittal sinus
What typically causes cavernous sinus thrombosis?
Spreading sinus infection
What tracts are affected in Brown-Sequard syndrome?
Descending lateral corticospinal
Ascending dorsal column
Ascending spinothalamic
What is the spinothalamic tract responsible for?
Anterolateral cord
Contralateral pain and temperature sensation
What is the dorsal column tract responsible for?
Posterior cord
Ipsilateral vibration and proprioception
What is the lateral corticospinal tract responsible for?
Ipsilateral movement of limbs
What is mononeuropathy?
Damage/dysfunction of a single peripheral nerve->most cause motor and sensory impairment
What is the most common mononeuropathy?
Carpal tunnel syndrome
What might be seen on examination in a patient with carpal tunnel syndrome?
Weakness of thumb abduction(abductor pollicis brevis)
Wasting of thenar eminence NOT hypothenar
Tinel’s sign-tapping causes paraesthesia
Phalen’s sign: flexion of wrist causes sx
What is radiculopathy?
Symptoms cuased by compression off a nerve root in the spinal common
Which vertebrae/nerve roots are typically affected by cervical radiculopathy?
C5-C7
What is the lateral spinothalamic tract responsible for?
Contralateral pain and temperature
What is the anterior spinothalamic tract responsible for?
Contralateral crude touch
What is the spinoreticular tract responsible for?
Deep/chronic pain
What is the corticospinal tract responsible for?
Ipsilateral control of voluntary muscles
Anterior-axial
Lateral-limb
What is the vestibulospinal tract responsible for?
Muscle tone and postural control
What is the DCML tract responsible for?
Ipsilateral vibration and proprioception
