extra + secondary care (neuro) Flashcards
features of a temporal lobe seizure (3)
Motionless staring, automatisms (such as lip-smacking) and post-ictal dysphasia
what is the traid of wernicke’s encephalopathy
- ophthalmoparesis with nystagmus;
- ataxia;
- confusion
what causes wernicke’s enephalopathy
subacute deficiency of thiamine (vitamin B1)
where do M1 neurons decussate
in the medulla-spinal chord
why is hyper-reflexia seen in pts w UMN lesions
lack of inhibitory modulation of the reflexes from the brain
if Hx of peripheral sensory involvement (e.g. numb feet) what else should be asked about and why
autonomic involvement e.g. bladder, bowel, sexual function -> the sympathetic chain may be involved in SC lesions but not usually in peripheral neuropathy
why are abnormal smells often seen in auras of those with mesial temporal lobe epilepsy
the primary rhinal cortex (smell) is situated close to the hippocampus (the site of seizure generation) -> smells are often associated with memory
occipital -> temporal lobe pathway (what does it encode)
‘what’ pathway i.e. what objects are, semantic memory
occipital -> parietal lobe pathway (what does it encode)
‘where’ pathway i.e. where in space objects are, spatial awareness
what is the fastest onset NDD
motor neuron disease
what is the commonest genetic neurological conditoin
charcot-marie-tooth disease
characterisitic history of progression of someone with charcot-marie-tooth
normal at primary school but gradual onset throughout life -> gradually get worse at sport etc.
what can cause brown-sequard syndrome
MS is the commonest cause but can also be caused by other inflammatory conditions
what DH tracts are supplied but the anterior spinal artery (2)
spinothalamic + motor
if there is a stroke in the anterior spinal artery what sensations remain intact
proprioceptions + fine touch + vibrations (i.e. whatever is in the dorsal column)
lead pipe vs clasp knife rigidity
lead pipe - persists throughout the range of movement of a particular joint, seen in PD
clasp knife - after an initial resistance to passive movement of a joint, there is a sudden reduction in tone and the limb moves quite freely through the rest of the range of the particular movement, seen in spasticity
what is Pseudoathetosis
movement disorder that is characterized by involuntary, slow, and writhing movements -> proprioceptive defect, can be seen when testing pronator drift
what is dysmetria
the inability to control the distance, speed, and range of motion necessary to perform smoothly coordinated movements - as sign of cerebellar damage
what muscle has pure C6 innervation
brachoradialis
what is hoffman’s sign
an involuntary flexion movement of the thumb and or index finger when the examiner flicks the fingernail of the middle finger down -> this is an abnormal sign and indicated UMN damage
what condition is pes cavus seen in
charcot-marie-tooth
how many beats is abnormal in clonus test
3-5 beats
what is a CT scan good for picking up (2)
- blood
- bone injuries (fractures)
i.e. trauma
what area of the brain/skull may have high numbers of artifacts in CT scans
posterior fossa
what gland may normal calcification be seen (on a CT head scan)
pineal gland
what does T1 vs T2 MRI show
T1 - anatomy;
T2 - pathology (fluid appears white)
what is malignant MCA syndrome
and increase in pressure due to massive MCA infarct in a young pt leading to mass effect (as less brain atrophy so no space for the swelling in the skull)
malignant MCA syndrome mgx
surgery - hemicraniotomy
what usually surrounds a haemorrhage in the brain and why
a haemorrhage is usually surrounded by oedema as blood is very irritable to the brain leading to inflammation
SAH CT presentation (not star sign)
may look like the sulci/gyri are “coloured in” (star sign not always present)
subdural vs extra dural blood supply (vein/artery)
subdural - venous => low pressure
extradural - arterial +> high pressure
what is a ring enhancing lesion (CT/MRI head)
an abnormal radiological sign where there is a lesion with area of hypodensity surrounded by a bright rim from contrast -> must be in a contrast scan
what can cause ring enhancing lesions (3)
- abcess;
- secondary tumour
- inflammation (e.g. demyelinating, but this is usually a ‘c’ shape)
why should a pt w a brain haemorrhage be rescanned at 6 weeks
to look for metastesis -> melanoma often metastesises to the brain and can cause tumours that haemorrhage
what 3 brain areas are demyelinating plaques commonly found in MS
- periventricular
- posterior fossa
- juxtacortical
how can symptoms arising from the commonly demyelinated areas (in MS) be distinguished from vascular disease
they are vascularly protected areas
meningiomas presentation (CT)
hyperdense region with areas of calcification and a tail coming out of it
encephalitis vs differntials - how to distinguish from a scan
encephalitis usually occurs bilaterally, if unilateral then consider a differential
what will an AVM look like on a T2 MRI scan
signal void - signal loss occurring within moving fluids, when the fluid is moving at a sufficient velocity relative to the MRI apparatus
how can ocular fatigability be checked
ask the pt to look up and see how long until they experience double vision (can also look at corneal light sign to tell this)
what does “bulblar” mean
the medulla oblongata, which looks like a swelling, or bulb, at the top of the spinal cord is known as the bulbar area -> damage to CN IX-XII leads to bulbar involvement
what infection causes LMN involvement only
polio
what is syringomyelia
a chronic progressive disease in which longitudinal cavities form in the cervical region of the spinal cord - a collection of cerebrospinal fluid within the spinal cord.;
This characteristically results in wasting of the muscles in the hands and shoulders (cape like distribution) and a loss of sensation
basal ganglia function analogy
a record player - involved in learned automatic activities e.g. walking, driving
what congential malfomation is syringomyelia associated with
Arnold-Chiari malformation
7 neurological emergencies
- SAH
- status epilepticus
- meningitis
- myastehnic crisis
- cauda equina
- stroke
- guillian-barre
why do learning difficulties increase the chance of status epilepticus
ppl are born with abnormal connections in the brain -> more likely to have continuous seizures
9 causes of seizure w not hx of epilepsy
- space occupying lesion
- meningitis
- CVD
- encephalitis
- SAH
- metabolic deragement (hypoglycaemia/natrurina etc.)
- alcohol intoxication
- withdrawal
- toxins (cocaine, carbon monoxide)
if glucose levels are low in someone with status epilepticus what should be done
- give glucose gel
- give buccal medazilone
what demographic of people is venous sinus thrombosis prevelent in
pregnant women
signs of venous sinus thrombus (4)
- headache
- ptosis
- increased ICH signs
- optic disc swelling
what is the normal opening prerssure of a lumbar puncture
9-12 mmHg
what should be checked in the CSF samples
- microscopy
- biochem
- xanthochromia (photosensitive so sample must not be exposed to light)
- presence of rbcs (check to see if levels are deceasing or remain the same -> if decreasing then likely just due to traumatic tap, if not then more serious cause)
what to look for in the LP of suspected guillian-barre
inflammatory features -> high protein but normal WBCs
4 key presenting features of gullian-barre
- ascending pattern
- symmetrical
- usually motor
- loss of deep tendon refelxes
what is weber’s syndrome
a form of midbrain stroke characterised by the an ipsilateral CN III palsy and contralateral hemiparesis
does a RAPD +ve finding indicate a partial or complete defect
partial defect pre optic chiasm
what infection might result in trigeminal neuralgia arising after it
shingles (post herpatic neuralgia)
what is the mgx of shingles
acylcovir 800mg x5 a day
what nerves does the corneal reflex test
CN V (afferent) and CN VII (efferent)
what is often a warning sign in someone about to have a seizure
looking up/away -> if seen help them to the ground
what can be done as risk reduction measures in someone having a seizure
remove scarves/other dangerous items; place something soft under their head
what is the most important thing to do when someone is having a seizure
time the length of the seizure
what should be done if there are signs of airway comprimise
place in recovery position -> otherwise don’t interfere until seizure is over (and then put in recovery position)
what might someone with temporal lobe epilepsy do during a seizure
wander around - stay with them + move objects out of their way
what is pre-eclampsia
high blood pressure during pregnancy and after labour -> may develop into eclampsia (fit)
what drug is given if someone experiences eclampsia
magnesium sulphate
what is hypomimea
lack of facial expression (parkinson’s)
lead pipe vs cogwheel rigidity
lead pipe - persists throughout the range of movement of a particular joint, seen in PD;
cogwheel - amalgamation of tremor + lead pipe rigidity simultaneously leading to cog-like movement
where is cogwheel rigidity best felt usually
at the wrist
why might sleep disruption be seen in PD
medication wears off at night leading to disordered dreaming
what part of normal gait is lost in shuffling gait
loss of heel strike (and reduced arm swing)
3 principle symptoms of PD
- tremor
- stiffness
- small movement impairment
11 non-motor PD symptoms
- sleep disturbances
- overproduction of saliva
- depression
- sweating problem (autonomic dysfunction)
- bowel/bladder dysfunction
- low BP
- loss of smell
- impulse control change
- seborrheic dermatitis
- visual hallucinations
- altered speech
what test should be done in an emergency situ in someone w Guillian-barre
spirometry - may show rapid respiratory depression
at what level is a lumbar puncture taken
L3-4
what is the cushing triad (raised ICP)
- hypertension (with wide pulse pressure)
- bradypnoea
- bradycardia
(opposite of shock)
