neuro Flashcards
what PMHx may suggest ischaemic stroke?
AF
previous TIA
carotid bruit
hemiparesis hemiplegia reflexes reduced hemianopia aphasia (if dominant hemisphere affected) ask about L/R handedness
cerebral hemisphere stroke- middle cerebral artery
eye problems predominant
posterior circulation infarct
LOC, locked in syndrome
diplopia, nystagmis
brain stem ischaemia
stroke- localised symptoms, pure motor/ sensory / ataxia, intact cognition + consciousness
lacunar infarct
suggestive of haemorrhagic stroke
bleed tendency/ anticoagulation
worsening symptoms
reduced GCS
severe headache
time limit for alteplase following ischaemic stroke
4.5 hours
ABCD2
TIA- indicates risk of further stroke
Age >60
BP >140/90
Clinical features- unilateral weakness (2)/ speech only (1)
Duration >60
DM
if 4+ start aspirin 300mg and specialist review in 24hours, if less then still 300mg and review in 1 week
ROSIER score
acutely to distinguish between stroke and stroke mimics
what is the most common cause of stroke
ischaemic
amaurosis fugax
sudden loss of vision in one eye- curtain, caused by infarct in retinal artery/ anterior TIA
prognosis after TIA
30% will have stroke, 15% MI
what level of carotid artery stenosis would require endarterectomy
> 60%
stroke- weak leg +/- shoulder on contralateral side
anterior cerebral artery infarct
long term secondary stroke prevention
aspirin 75mg OD, clopidogrel if can’t tolerate aspirin
dipyridamole if confirmed ischaemic
warfarin if AF
RFs
3 most common pathogens causing meningitis infants
neisseria meningitidis
strep pneumoniae
Hib- Hib < common in older/ adults
gram negative coccobaccilus meningitis
Hib
gram negative cocci meningitis
neisseria meningitidis
gram positive cocci meningitis
strep pneumoniae
Kernig’s sign
flex the hip, with the knee flexed. Now extend the knee. Positive test if there is spasm of the hamstrings.
meningitis
Brudzinski sign
passively flex the neck. Positive test if there is flexion of the hip and/or knee.
meningitis
signs of raised ICP
reduced GCS
papilloedema
high BP/ low HR
focal neuro signs
non-infective causes of meningism
leukaemia
lymphoma
Breast cancer
which is the most common cause of meningitis
viral (2/3)
echovirus/ mumps/ EBV, VZV, HSV/ influenza
Bacterial meningitis tx
3rd generation cephalosporin (cefotaxime)
treat household contacts with rifampicin
2 causes of subarachnoid haemorrhage
aneurysm rupture
AV malformations
(trauma)
diseases that increase risk of berry aneurysms
PCKD, co-arctation of aorta, Ehlers-Danlos
pathology of brain injury in SAH
haemorrhage stops -> vasospasm-> secondary ischaemia, secondary acute hydrocephalus
if suspect SAH but CT -ve what is next investigation?
LP
what can help to prevent secondary ischaemia in SAH
nimodipine
1st line in status epilepticus
4mg lorazepam IV, repeat after 10 mins. if no response ?add phenobarbitone (must have ECG)
buccal midazolam if no IV
CN I
olfactory
CN II
optic
CN III
oculomotor: motor- SR/ MR/ IR/ IO/ Levator palpabrae
parasympathetic- ciliary muscle/ pupil constriction
CN IV
trochlear- SO
CN V
trigeminal- sensory
motor- muscles of mastication
CN VI
abducens- motor to LR
CN VII
facial motor to muscles of expression, sensory to ant 2/3 tongue
parasympathetic to salivary and lacrimal glands
CN VIII
vestibulocochlear sensory
CN IX
glossopharyngeal- sensory to middle ear, sinuses, posterior 1/3 tongue and pharynx motor styropharyngeous (swallow) parasympathetic- salivary glands
CN X
vagus
sensory- pharynx/ larynx/ oesophagus, aortic bodies, thoracic/ abdo viscera
motor- soft palate- speech and swallow
parasympathetic - CV/ GI/ resp
CN XI
accessory motor to sternomastoid and trapezius
CN XII
hypoglossal
motor to tongue
fixed dilated pupil and ptosis
CN III injury
injury to CN IV causes
down and in deviation
injury to CN VI
eye deviated medially
unilateral face weakness
unable to show teeth, screw eye and raise eyebrow on affected side
Bell’s palsy- ?viral induced facial nerve palsy
how would you distinguish between UMN and LMN lesion in suspected Bell’s palsy?
UMN forehead spared- stroke
LMN Bells palsy
treatment of Bell’s palsy
self resolve, steroids most effective in first 72 hours
assymetrical raising of uvula?
CN X
deviation of tongue
CN XII
Mnemonic for peripheral nerve lesions
DAVID DM Alcoholism Vit deficiency (B12) Infective/ Inherited- GBS/ Charcot Marie Tooth Drugs- isoniazid
mechanisms of peripheral nerve degenaration
demyelination- GBS axonal degeneration- toxic wallerian degeneration- axon crushed/ cut compression- carpal tunnel syndrome infarction- DM infiltration- malignancy, inflammation
compression of which nerve causes carpal tunnel
median by flexor retinaculum
signs of median nerve compression
wasting of thenar eminence
paraesthesia of lateral 3.5 fingers
pain/ tingling in lateral 3 fingers
phalen’s test
hold wrist in flexed position for up to 2 mins, exaggerates symptoms of carpal tunnel
Tinel’s test
Tap over medial aspect of inside wrist induces tingling
management of carpal tunnel
splint + NSAIDs hydrocortisone injection (1 month) surgical decompression
clearly defined history of trauma- subdural or extradural
extradural
where does bleeding come from in subdural
bridging veins
crescent of blood on CT head
subdural
how is ICP relieved in subdural/ exrtadural haemorrhage
Irrigation / evacuation / Burr hole craniostomy/ craniotomy
where does bleeding come from in extradural
middle meningeal artery/ vein
lemon shaped blood not crossing suture lines on CT head
extradural
appearance of symptoms in subdural vs extradural
subdural- symptoms fluctuate over time
exradural lucid period up to 24 hours then progressive worsening
which cells are damaged in MS
oligodendrocytes
MS- Mostly UMN/ LMN signs
UMN- optic nuritis, afferent pupillary defect, sensory (numbness/ paraesthesia)/ autonomic (urinary incontinence, constipation, sexual dysfunction), cerebellar ataxia, fatigue
end-stage MS
spastic ataxia
brainstem signs
dementia
dx of MS
1+ Attack
plaques on MRI
Management of acute MS
steroids methylprednisolone to induce remission
preventing relapse in MS
B interferon
Lehrmitte’s sign
on voluntary flexing of the head, there is an electric shock sensation travelling down the spine and into the limbs- MS
Uthoff’s phenomenon
signs worse on hot day or after exercise- MS
urinary incontinence in MS
when residual volume is >100ml, manage with oxybutinin, or self-catheterisation
