Neurology Flashcards
what is an extra-dural haematoma?
aka epidural haematoma
traumatic brain injury can cause an artery to haemorrhage (usually middle meningeal artery)
blood builds up between skull and dura
how is an acute rise in ICP managed?
1) heavy sedation +/- paralysis
2) manitol (osmotic diuretic - draws water across BBB into circulation)
3) hyperventilation - decreased PaCO2
4) CSF drainage
5) barbiturates = phenobarbitone - into coma
6) surgical treatment
- decompressive craniectomy (decreases ICP by 15%, if open dura as well, decrease ICP by 70%)
what are the common benign brain tumours?
- meningioma 20%
- pituitary tumour 5%
- neural sheath tumour (vestibula schwannema) 5%
how does a tension like headache present?
bilateral, band like headache mild-moderate pain lasting ~30 mins no vomiting or nausea may have slight photo OR phonophobia (not both) scalp muscle tenderness possible due to head/neck muscle tension not worsened with daily activities
how does a subdural haematoma present?
traumatic injury AND seizures, incontinence, neurological decline
occurs slowly (veins leak slower than arteries) - can present days - months after injury
fluctuating levels of consciousness for a period of time is typical as the haematoma contracts and expands due to osmotic effect
what is the monro kellie doctrine?
increase in components in the cranium will cause displacement of other components = compliance
compliance phase ends when no more components to displace and then ICP begins to raise
in relation to migraines, which medication can cause an overuse headache?
triptans
analgesia
treated with cessation
how do you define chronic/episodic cluster headaches?
chronic = remission < 7 months in 12 months episodic = 1 every other day up to 8 a day = remission ? 1 month
how are cluster headaches treated?
acutely = oxygen and nasal/subcutaneous triptans prophylaxis = verapamil, prednisolone
what are syndromes causing familial brain tumours?
neurofibromatosis
von hippel lindau syndrome
tuberous sclerosis
how is a subdural haematoma treated?
IF <10MM, NON-EXPANSILE, NO SIG. NEUROLOGICAL DEFICITS
1) observe, monitor GCS, imaging
2) prophylactic anti-epileptics (phenytoin, phenobarbital)
3) correction of coagulopathy
4) ICP lowering regime
IF >10MM, EXPANSILE AND W/ NEURO DEFICITS
1) Surgery!
- burr hole drainage (saline washout and suction of clot)
- craniotomy and duraotomy (removal of clot)
what maintains cerebral perfusion
CP = mean arterial BP - ICP
raise in ICP means need a raise in arterial BP to maintain cerebral perfusion
how do you classify an acute or chronic headache?
occurring on <15 days a month = ACUTE
occurring on >15 days/month for 3 consecutive months = CHRONIC
how is a tension type headache treated?
stress relief
aspirin/ibruprofen
drink water - to rule out dehydration
what does the prophylactic treatment of migraines include?
1ST LINE
1) beat blocker (propranolol) or topiramate (anti-epileptic- teratogenic)
2) Amitriptyline
3) oestrogen patches for women with menstrual related migraines
2ND LINE
1) Antiepilpetics = sodium valproate/topiramate
2) antihypertensive medication may help some.
3) 12 weekly Botox injections = last resort
features of MRI?
magnetic waves
more expensive
takes longer, noisier
better spatial resolution of soft tissue lesions
better identifying between normal/abnormal tissues
what are the diagnostic criteria for migraines?
If no aura present:
1) 5+ headaches lasting 4-72 hours
2) with nausea/vomiting (or photo/phono phobia)
3) and 2 of the following
- throbbing/pulsating
- made worse by routine activities
- unilateral
what is 1st investigation for suspected cranial haematoma?
non contrast CT scan
what are triptans?
strong serotonin agonist - causes vasoconstriction
used to treat migraines
shouldn’t be used more than 10 days a month
CI = IHD, HTN, recent lithium, SSRIs, vasospasms
rare SE - arrhythmias, angina, MI
can take a second dose if needed, must take 2 hours apart
what are routine measures to control raised ICP?
1) head up tilt (30-40 degrees)
2) prevent hypertension - use vaso-suppressins
3) sedate - decrease metabolic demands
4) keep neck straight and free
5) maintain euvolemia and normal osmolar state
6) maintain normal PaCO2 ( can raise cerebral blood volume and vasodilation)
what is a subarachnoid haemorrhage?
bleeding into the subarachnid space - between the arachnoid and pia matter
how does a migraine present?
mainly women
can present as:
aura lasting 15-30 mins followed by unilateral, throbbing headache
OR
isolated aura without headache
OR
episodic severe headaches without aura. usually premenstrual
headache associated with nausea, vomiting, prodrome (precedes headache by hours/days = cravings, yawning, mood/sleep changes), allodynia (all stimuli cause pain e.g. wearing glasses, hair brush)
throbbing pain can last hours - 3 days
how does a subarachnoid haemorrhage present?
thunderclap severe headache vomiting seizures confusion decreased consciousness
how do cluster headaches present?
unilateral, very severe headache - occurring around the eye and side of face.
associated with agitation, restlessness.
occurring on same side as headache: red, watery eye, swollen eye, nasal congestion and runny nose, sweating, droopy eyelid and constricted pupil
lasting 15-80 minutes
what is considered pathological ICP?
persistently > 20 mmHg
how may auras associated with migraines present?
- visual; sincillating scotoma - chaotic, jumbling, partial loss of vision - in one eye or half of visual field in both eyes
- somatosensory - paraesthesis spreading from fingers to face
- motor - dysarthria (unclear speech) and ataxia (basilar migrain)
- speech = dysphasia or paraphasia
what is a subdural haematoma?
disruption of bridging veins travelling to the dural venous sinuses- leads to a bleed
blood builds up inbetween dura and arachnoid mater
what are common triggers for migraine?
CHOCOLATE
chocolate, hangovers, orgasms, cheese, caffiene, oral contraceptive, lie-ins, alcohol, travel, exercise
loud sounds, flickering lights, menstruation
how are brain tumours classified?
primary/secondary
malignant/benign
supertentorial (mostly adults)/infratentorial (children)
when should prophylactic treatment be considered for migraines?
if >2 headaches a month