neurology Flashcards
clinical features of MND/ALS
cognitive decline
muscle weakness/wasting
spasticity
dysphagia/dysarthria
due to death of upper and lower nerves
Risk factors for ALS/MND
mostly sporadic
mild increase if FHx
400 people living in NZ w ALS
tx of ALS/MND
no curative tx
MDT support
NIV
some supportive medications
what is MS
Autoimmune demyelinating disease of CNS nerves. Peripheral nervous system unaffected.
- inappropriate immune cell activation and destruction with myelin (which surrounds/protects nerves). leaves plaques behind
Early: remyelination
Later: nerve unable to repair itself
Risk factors for MS
HLA-DR2
Female
age 20-40yrs
further from equator / vit D deficiency
infections
FHx
Smoking/EBV
Types of MS
relapsing/remitting: bouts of immune attack (most common 85% )
secondary progressive
primary progressive
progressive relapsing
how does MS present
sudden episode of neurological sx
- optic neuritis, diplopia
- weakness, gait disturbances and ataxia
- tremor
- bladder dysfunction, bowel or erectile problems
- sensory changes
- muscle spasm/pain
- neuralgia
- fatigue (85%)
worsen over days-weeks then gradually resolve
often (50%) later develop depression and cognitive decline
Lhermitte’s symptom
An electric shock sensation down the spine when the neck is flexed
characteristic, but not specific, for MS
how does optic neuritis (MS) present
optic neuritis are
- reduced visual acuity
-reduced colour vision (red desaturation)
- eye pain, especially on eye movement.
O/E: papilloedema and RAPD (due to optic nerve damage)
main cause MS
ddx: ischaemic optic neuropathy, inflammatory optic neuropathies
what is the Mcdonalds criteria with MS
a diagnosis of MS requires 2 or more episodes of inflammatory demyelination to occur on separate occasions, at least 30 days apart, in different locations within the CNS.
sometimes MRI scans can be used instead when there’s a prev hx
MS and pregnancy
MS does not affect fertility
Relapses are less likely during pregnancy, but more common 3-6 months post partum
Disease-modifying medicines should be avoided 3 mths prior and during pregnancy
timing for stroke thrombolysis
has to be <4.5hrs from symptom onset
ideally <3 hrs
usually with alteplasia - 30% more likley to have no disability @ 3mths
when do you give aspirin in the setting of a stroke
once a haemorrhagic streoke has been excldue from imaging
given 150-300mg asap, if thrombolysing delay by a few days
cont 100mg long term
What is idiopathic intracranial hypertension (IIH)?
Raised ICP in the absence of a mass lesion or of hydrocephalus.
appears to be due to impaired CSF absorption
can lead to significant visual impairment, so prompt recognition and treatment are needed to prevent potentially permanent visual changes including partial or total loss of vision.
Risk factors for Idiopathic intracranial hypertension
obese women at childbearing age
menstrual irregularity
assoc w endocrine pathology and some meds
symptoms of IIH
Headache worst first thing in the morning and last thing at night.
- relieved on standing
- worse with straining, coughing or a change in position
Gradual visual field defects;
- moderate or gross bilateral papilloedema without significant focal intracranial signs.
Daily transient visual obscurations (TVOs) (‘greying out’) on bending or stooping, halo or a short episode of visual wheel flashes, persistent blurring, scotoma or horizontal diplopia often occur.
Nausea, vomiting, drowsiness.
Diplopia (due to VI cranial nerve palsy)
Ix in IIH
Bloods
eye exam
lumbar puncture
CT or MRI
predictors of poorer outcomes in patients with a concussion
Initial symptom burden
Previous concussions
Pre-existing mental health conditions
Being female.
The presence of migraine-like symptoms or a history of migraine
Younger and older age groups
People with alcohol and substance abuse issues
Predominance of vestibular symptoms,
what are the recommended time frames for return-to-sport in patients post concussion
24 – 48 hours of physical and mental rest
2 – 13 days post-injury, progressively re-engage in normal daily activities, should be guided by symptoms.
> 14 days and symptom free: re-engage in full contact training
> 21 days and symptom free during training: return to competition
bloods to do when differentiating dementia from delerium
Full blood count
electrolytes, creatinine, calcium, glucose, HbA1c, renal and liver function
TFTs
B12 and folate
CRP
HIV and syphilis testing
Mid-stream urinalysis – if a UTI is suspected
what symptoms would you see with a common peroneal nerve injury
foot drop (weak dorsiflexion and foot eversion)
sensory loss over the dorsum of the foot and the lower lateral part of the leg
The sciatic nerve divides into the tibial and common peroneal nerves. Injury often occurs at the neck of the fibula
what would you see in a tibial nerve injury
weak plantarflexion (pointing the foot downward)
weak inversion of the foot.
These are the opposite movements to those affected by common peroneal nerve injuries.
stroke long term prevention
- Clopidogrel monotherapy is generally considered the best first-line
Dose is 300 mg immediately, then 75 mg daily.
Dual antiplatelet therapy (DAPT) with clopidogrel (300 mg load then 75 mg daily) + aspirin (300 mg load then 100 mg daily) is recommended for 3 weeks in patients with a TIA or minor stroke. DAPT is not used after a moderate or severe stroke.
After 3 weeks, stop the aspirin and continue with clopidogrel monotherapy.
- Dipyridamole + aspirin (100 mg daily)
- Aspirin monotherapy (100 mg daily)
what is Bells palsy
acute, unilateral, idiopathic, facial nerve paralysis
Lower motor neuron palsy, forehead affected
treatment: PO pred (if <72 hrs) and artificial tears and taping (prevent keratopathy)
prognosis for Bells Palsy
most people make a full recovery within 3-4 months
if untreated around 15% of patients have permanent moderate to severe weakness
refer to ENT if no improvement on steroids after 3-4 weeks
arm fracture resulting in radial nerve damage, what would you see on exam
wrist drop
reduced sensation on dorsal hand 1-2nd MCPs
signs of a 3rd nerve palsy
eye is deviated ‘down and out’
ptosis
pupil may be dilated
how do lacunar strokes present
- purely motor
- purely sensory
- sensorimotor stroke
- ataxic hemiparesis
due to occlusion of a single penetrating branch of a large cerebral artery and affect the internal capsule, thalamus and basal ganglia.
when can you return to driving after a TIA
Car or motorcycle licence:
Single TIA
Multiple TIAs
Commercial licence:
Single TIA:
Multiple TIAs:
Car or motorcycle licence:
Single TIA – 1-month
Multiple TIAs – 3-month + on tx
Commercial licence:
Single TIA: Minimum 6-month + specialist clearance
Multiple TIAs: Minimum 12-month
classic symptoms for an acoustic neuroma
vertigo, unilateral tinnitus, hearing loss, absent corneal reflex
how to treat a medication overuse headache
abrupt withdrawawl of everything (except benzos and opiods)
if that doesnt work start a TCA or topirimate and retry
++ sleep and avoid caffeine
