Neurology Flashcards
Describe the GCS scoring system of consciousness
max = 15, minimum = 3
< 8 consider intubation
eyes = 4 verbal = 5 motor = 6
What functions are associated with the frontal lobe?
higher intellectual function
personality, mood
social conduct + behavior
motor areas (post. frontal)
conjugate eye movements + frontal eye fields
language
what functions are associated with the temporal lobe?
memory
language
visual pathway (optic radiation)
what functions are associated with the parietal lobe?
DOMINANT HEMISPHERE
language, reading, writing
calculation
praxis
NON-DOMINANT HEMISPHERE
visuo-spatial function
BOTH
higher sensory function
visual pathway
what functions are associated with the occipital lobe?
visual cortex and visual association areas
What visual field defect would a patient present with if they have a lesion in the optic chiasm?
bitemporal hemianopia
What might cause an enlargement of a physiological blind spot?
papilloedema
what is tunnel vision?
loss of peripheral fields but preservation of central region
what are some causes of tunnel vision?
chronic glaucoma
retinitis pigmentosa
cortical disease
may be functional meaning no disease
which eye muscles does CN III supply?
superior rectus muscle, medial rectus muscle, inferior rectus muscle, inferior oblique muscle
which eye muscles does CN IV supply?
superior oblique muscle
which eye muscles does CN VI supply?
lateral rectus muscle
what are the features of CN III palsy?
ptosis
eye points down and out
if PNS fibres involved pupil fixed and usually dilated
What are causes of a third nerve (CN III) palsy?
compression:
- brainstem by tumour or basilar aneurysm
- tentorial herniation (coning)
- posterior communicating artery aneurysm
- cavernous sinus: tumous, aneurysm, thrombosis
- superior orbital fissure SOL (tumour, granuloma)
infarction:
brainstem or at nerve trunk (DM, HTN, GCA, SLE)
inflammation or infiltration of basal meninges involving nerve
features of fourth nerve palsy
isolated unilateral paralysis of superior oblique
diplopia doing down stairs
may hold head tilted to normal side
features of sixth nerve palsy
unable to abduct affected eye
diplopia looking to affected side
features of Horner’s syndrome
partial ptosis
miosis (pupil constriction)
anhydrosis
what are upper motor neurones?
neurons whose cell bodies are in the motor cortex and their axons are in the corticospinal tract synapsing with anterior horn cells
what are lower motor neurons?
motor neurons with axons extending from anterior horn cells of the spinal cord to voluntary muscles.
one supplies one motor unit
are fasciculations LMN or UMN signs?
LMN
what kind of gait may UMN lesions lead to?
spastic, scissoring, circumduction
what modalities of sensation are transmitted via the dorsal columns?
position
vibration sense
what modalities of sensation are transmitted via the spinothalamic tracts?
pain
temperature
what is the dorsal column pathway?
Ascending pathway (from PNS to CNS)
info from preceptors -> primary sensory neurone -> enter dorsal root -> cord -> ascends in dorsal columns (same side) -> brainstem (medulla) -> desiccates (crosses sides) -> third neurone -> thalamus to cerebral cortex (parietal lobe)
what is the spinothalamic column pathway?
primary sensory neurone -> enters cord via dorsal root -> desiccates -> ascends in contralateral spinothalamic tract (crosses over within a few segments) -> thalamus -> third neurone -> cortex.
what bodily functions and systems are affected by autonomic dysfunction?
pupils
BP and HR
bladder, bowel, sexual function
sweating, lacrimation, salivation
indications for a diagnostic LP?
meningitis, encephalitis
SAH
MS
Huntington’s disease
inflammatory disorders = syphilis, sarcoid, GBS
idiopathic intracranial HTN
myelography
indications for a therapeutic LP?
intrathecal chemo
removing CSF in IIH or post-op
spinal anaesthesia
Contraindications for LP
suspect or actual intracranial mass (risk of coning)
bleeding disorder
significant spinal deformity
what antibodies should be tested for if you suspect myasthenia gravis?
anti-acetylcholine receptor antibodies
anti-MuSK antibodies
What is a myasthenic crisis and how do you treat?
weakness of respiratory muscles during a relapse
ventilate if < 20mL/kg
plasma or IV Ig
treat any trigger for relapse
What are the causes of lamber-eaton myasthenic syndrome?
disorder of NM transmission due to impaired presynaptic release of ACh
causes: paraneoplastic (small cell lung CA) or autoimmune
how is lambert-eaton different to myasthenia gravis?
in lambert eaton:
- gait affected before eyes
- autonomic involvement
- hyporeflexia and weakness which improves with exercise
what criteria is used for MS?
Mcdonald criteria
what is the triad of parkinsonism?
tremor (worse at rest, pill-rolling, 4-6 cycles per second)
rigidity
bradykinesia/hypokinesia
what sort of a gait do parkinson’s patients have?
reduced arm swing, short shuffling steps with flexed trunk, freezing at obstacles/doors
what might pale optic discs indicate?
previous subclinical optic neuritis
Which is forehead sparing?
a) UMN
b) LMN
UMN
describe a spastic gait
stiff movement of legt in an arc
might be post stroke
describe the walk of a patient with sciatic nerve injury
drop foot + high stepping gait
describe sensory ataxia
board based high-stepping gait
this is due to peripheral neuropathy leading to deficits in proprioception
tender pulseless temporal arteries, jaw claudication
GCA
signs of parkinsons
lead-pipe rigidity, cog-wheel rigidity, pill rolling tremor, festinant gait with poor arm swing
onset of chorea in middle age with dementia onset later on
Huntington’s disease
gait apraxia, confusion, incontinence
normal pressure hydrocephalus
cauda equina syndrome signs
saddle anaesthesia, bowel/bladder dysfunction
triad of nystagmus + opthalmoplegia + ataxia
wernicke’s encephalopathy
nerves responsible for the supinator reflex
C5 and C6
nerves causing biceps reflex
C5 and C6
nerves causing triceps reflex
C7
unilateral weakness/sensory deficit, homonymous hemianopia, higher cerebral dysfunction (dysphasia, neglect)
anterior circulation stroke
CN palsies, cerebellar signs (vertigo, dysarthria, ataxia, choking)
isolated homonymous hemianopia
posterior circulation stroke
which cancers commonly metastasis to the brain?
thyroid
lung
breast
stomach
colorectal
prostate
what are features of SOL in the brain?
headache - worst in the morning and on lying down
nausea + vomiting
seizures
progressive focal neurological deficits
cognitive + behavioural changes
papilloedema + vision changes
what are the cardinal features of cluster headaches?
trigeminal distribution of pain
same-sided cranial autonomic symptoms
pattern to the attacks
what is the main causative organism of encephalitis?
most common is HERPES VIRUS
what is the primary bacterial cause of meningoencephalitis?
neisseria meningitides
what organisms are important to consider in an immunocompromised patient presenting with encephalitis?
CMV
toxoplasmosis
listeria
what are the signs of a raised ICP on examination?
reduced GCS
hypertension
bradycardia
irregular breathing pattern
papilloedema
what are the types of focal seizure?
complex partial seizure (reduced consciousness)
simple partial seizure (consciousness not affected)
focal seizures may progress to generalised seizures
what are the types of generalised seizure?
tonic (stiffening of body)
myoclonic (limb jerking)
tonic-clonic (reduced consciousness, muscle stiffening, convulsions)
absence seizures
atonic seizures (sudden loss of muscle tone -> collapse)
what are some secondary causes of seizures?
brain = tumours, infection, inflammation, haemorrhage, trauma, neurodegenerative diseases
toxic/metabolic = sodium imbalances, alcohol withdrawal
systemic = malignant HTN, eclampsia
what is todd’s paralysis?
this is a post-ictal state where the patient has flaccid muscle tone
typical of a frontal lobe, focal or motor seizure
how do you treat status epilepticus?
- ABC, check glucose, ABG for electrolytes
- IV lorazepam or PR diazepam or buccal midazolam. can repeat step 2 up to 2 times
- IV phenytoin infusion + ECG monitoring
- diazepam infusion + close respiratory monitoring
- general anaesthesia + intubation + ICU
what anti-convulsant is commonly used to treat focal seizures?
lamotrigine or carbamazepine
what anti-convulsant is commonly used to treat general seizures?
sodium valproate
what is the inheritance pattern of huntington’s?
autosomal dominant
what is the genetic mutation responsible for huntington’s?
expanded CAG repeat in the gene for the huntingtin protein
more than 40 repeats indicates huntington’s. < 28 is normal
what are the types of hydrocephalus?
non-communicating/obstructive = flow of CSF is blocked causing build up
communicating - communication between ventricles and subarachnoid space causing reduced absorption or venous drainage
normal pressure hydrocephalus = idiopathic chronic ventricular enlargement. may lead to white matter tract damage over time
what is the triad of features seen in normal pressure hydrocephalus?
dementia
gait disturbance
urinary incontinence
what are common viral causes of meningitis?
enteroviruses
mumps
herpes
VZV
HIV
what are common causes of meningitis in neonates?
group B streptococci
E. coli
listeria
what are common causes of meningitis in children?
H. influenza
N. meningitides
strep. pneumoniae
what are common causes of meningitis in adults?
N. meningitides
S. pneumoniae
TB
what are common causes of meningitis in elderly?
s. pneumoniae
listeria
what is the commonest cause of fungal meningitis and who does it affect?
cryptococcus
immunocompromised patients
what are some common auras experienced by migraine patients?
VISUAL - chaotic cascading, distortions, dots, ZIGZAG lines, jumbling of lines, defects in visual field
SENSORY - parasthesia
MOTOR - dysarthria, ataxia, opthalmoplegia, hemiparesis
what are some triggers for migraines?
CHOCOLATE
CHOCOLATE
HANGOVERS
Orgasims
CHEESE
ORAL CONTRACEPTIVE PILL [very important]
Lie-ins
ALCOHOL
Tumult
Exercise
what are neurological abnormalities do not occur in MND?
patients have NO sensory loss or sphincter disturbance
what is the most common type of MND?
amyotophic lateral sclerosis
what is the MRC scale?
0 - no constraction
1 - flicker or trace contraction
2 - active movement in the plane of gravity
3 - active movement against gravity, but not resistance
4 - active movement against gravity + resistance but WEAK
5 - normal power
what sort of an immune response causes MS?
t cell response
what condition is lambert eaton associated with?
small cell lung carcinoma
which antibodies are commonly implicated in MG?
anti-acetylcholine receptor antibodies (90%)
MUSK antibodies
difference between neurofibromatosis 1 and 2?
1 - presents with skin symptoms (e.g. cafe au lait) + other issues + increased CA risk. most common type
2 - CNS tumours rather than skin lesions. schwannomas, meningiomas, gliomas, cataracts
what is the urine test for multiple myeloma?
bence-jones proteins
what is the pharmacological management of tension headaches?
ibuprofen 400mg
TCA such as amitriptyline for chronic tension headaches
does a stroke to the middle cerebral artery affect the upper limbs or lower limbs more?
upper limbs + trunk
do strokes involving the anterior cerebral artery affect the upper limb or lower limbs more?
lower limbs
what are cardiac sources of emboli?
AF
post MI (mural thrombus is dislodged/broken up)
valve disease or prosthesis
venous clot passing through PDA or VSD
what are the components of the ABCD2 score and what is the scores significance?
Age > 60
BP > 140/90
clinical features (weakness, speech disturbance no weakness)
duration > 1hr = 2, 10-59 = 1
diabetes
maximum = 7
over 6 = very high risk of stroke
all over 4 to be assessed within 24 hours by specialist
used for TIA
what is the management of TIA?
is a suspected TIA has occurred in the last 24 hours load with 300mg aspirin
once confirmed load with 300mg clopidogrel and give high intensity statin therapy (atorvastatin 20-80mg)
what is the triad for wernicke’s encephalopathy?
mental status change
opthalmoplegia
gait dysfunction
what deficiency causes wernicke’s encephalopathy?
thiamine deficiency
describe the motor component of the GCS score?
1 = no movement 2 = abnormal extension to pain - decerebrate 3 = abnormal flexion to pain - decorticate 4 = withdraws from pain 5 = localises to pain 6 = obeys commands
what are signs of an UMN lesion?
increase tone (spasticity)
reduced power
hyperreflexia
upgoing plantar reflex
what are the signs of a LMN lesion?
reduced tone (flaccid)
reduced power
hyporeflexia
What are signs of cerebellar pathology?
DANISH
Dysdiadochokinesia (tested with rapid alternating movements)
Ataxia
Nystagmus
Intention tremor
Speech - slurred, scanning
Hypotonia
How would you manage a stroke?
< 4.5 hours - CT if no haemorrhage THROMBOLYSIS
> 4.5hrs - CT head to exclude haemorrhage, aspirin, swallow assessment, maintain hydration + oxygenation + monitor glucose
How would you manage a TIA?
aspirin
ECG, echocardiogram
Carotid doppler
Risk factor modification
what are the features of a third nerve palsy?
- eye deviated down and out
- dilated pupil
- unilateral complete ptosis
causes of 3rd nerve palsy?
- Posterior communicating artery aneurysm (painful)
- Neurosurgical emergency
- Hypertension
- Diabetes
- MS
- Others - trauma, bleed, tumour
surgical vs medical
- surgical - extrinsic compression
- medical - affecting nerve directly in some way
how does pupil dilation help determine cause of 3rd nerve palsy?
- Surgical causes - early pupil dilation, PNS nerves are on the outside so are compressed early when there is an extrinsic cause
- Medical - pupil dilation is a late sign, damage to 3rd nerve occurs from inside to outside
- Other investigations - excluding chronic medical issues
causes of ptosis
- Unilateral
- Horner’s syndrome
- 3rd nerve palsy
- Congenital
- Bilateral
- Myasthenia gravis
- Myotonic dystrophy
- Oculopharyngeal muscular dystrophy
- Mitochondrial disease (e.g. Kearns-Sayres)
how does pupil size and ptosis help differentiate the issue?
- Ptosis + large pupil → 3rd nerve
- Ptosis + small pupil → Horner’s syndrome
- Ptosis + normal pupil → myasthenia and other
causes of 6th nerve palsy + finding
failure of eye abduction
- Hypertension, DM, MS, raised ICP
signs of raised ICP
- Papilledema (late sign usually)
- Loss of retinal vein pulsation in fundus (early)
- Hypertension, bradycardia and abnormal breathing pattern - Cushing’s triad
- Focal neurology
- Including other CN palsies
- seizure
- ↓ GCS
causes of wasting of small muscle of the hands
unilateral
- Pancoast’s tumour
- brachial plexus trauma
- cervical rib
bilateral
- RA
- cervical spondylosis
- MND
- CMT
- syringomyelia
- bilateral cervical ribs
how to localise site of lesion causing a 7CN palsy?
- assess CN 6, 5 and 8
- if 6 has defects too → pons lesion
- if 5 and 8 have defects too → cerebello-pontine angle
features of 3rd nerve palsy
- Eye deviated “down and out”
- Ptosis
- Dilated pupil
- Early in surgical, late in medical as PNS on periphery of CN3 nerve bundle
causes of 3rd nerve palsy
- Medical
- DM
- MS
- Vasculitis
- SOL
- Weber’s syndrome - midbrain stroke
- Cavernous sinus thrombus
- Surgical
- Trauma
- Posterior communicating artery aneurysm
- Uncal herniation due to ↑ ICP giving false “localising sign”
what does the facial nerve supply (CN7) ?
- Muscles of facial expression
- Stapedius of ear
- Anterior 2/3 of tongue sensory
- PNS fibres to lacrimal and salivary glands
causes of bilateral facial nerve palsy
- Sarcoidosis
- GBS
- Bilateral acoustic neuroma - NF type 2
causes of unilateral facial nerve palsy (CN 7)
- LMN
- MS
- Bell’s palsy
- Ramsey Hunt
- Acoustic neuroma
- Parotid tumours
- HIV
- DM
- UMN
- MS
- Stroke
features of 4th nerve palsy
trochlear nerve
- Innervates superior oblique (moves eye out and down)
- Features
- Vertical diplopia
- Going down stairs or reading book
- Subjective tilting of objects
- Head tilt
- Eye up and rotated out
- Vertical diplopia
what is lateral medullary syndrome and it’s features
- After posterior inferior cerebellar artery
- Features
- Ataxia
- Nystagmus
- Brainstem features
- Ipsilateral: dysphagia, facial numbness, CN palsy (e.g. Horner’s)
- Contralateral: limb sensory loss
Oxford stroke classification
total anterior circulation stroke
- requires 3 criteria:
- Unilateral weakness (and/or sensory deficit) of face, arm and leg
- Homonymous hemianopia
- Higher cerebral dysfunction - dysphasia, visuospatial disorder
- Most common site of occlusion for TACS is the MCA, due to complete blockage of vessels
Oxford stroke classification
partial anterior circulation stroke
- requires 2 of the 3
- Unilateral weakness (and/or sensory deficit) of face, arm and leg
- Homonymous hemianopia
- Higher cerebral dysfunction - dysphasia, visuospatial disorder
- Involves smaller arteries in the anterior circulation e.g. upper or lower division of the MCA
Oxford stroke classification
lacunar stroke syndrome
- arises from smaller vessels being affected and has no loss of cortical function.
- Infarcts in perforating arteries around the basal ganglia, internal capsule, thalamus or pons
- 1 of the following:
- Pure sensory stroke
- Pure motor stroke
- Sensori-motor stroke
- Ataxic hemiparesis
oxford stroke classification
posterior stroke syndrome
- different presentation. May have a varied clinical picture.
- Involves the vertebrobasilar arteries
- Need 1 of the following for diagnosis:
- CN palsy and contralateral motor/sensory deficit
- Bilateral motor/sensory deficit
- Conjugate eye movement disorder e.g. horizontal gaze palsy
- Cerebellar dysfunction e.g. vertigo, nystagmus, ataxia
- Isolated homonymous hemianopia
causes of hemiplegic gait
- spastic flexion of upper, extension of lower
- circumduct their leg
- unilateral
- stroke, SOL, trauma, MS
- bilateral
- trauma hemisection of spinal cord
diplegic gait
- scissoring gait
- spine + sensation affected
- prolapsed disc, spinal spondylosis, spinal tumour, transverse myelitis, spinal infarct, syringomyelia, hereditary spastic paraperesis
- bilateral brain
- cerebral palsy, MS, bilat. brain infarcts, midline tumour
- MND
causes of shuffling gait
parkinson’s
causes of ataxic gait
- cerebellar ataxia
- cerebellar stroke, SOL, MS, ETOH, B12 def, drugs, Frederich’s ataxia, paraneoplastic
- sensory
- peripheral neuropathy (DM)
- vestibular
- labyrinthitis
- Meniere’s disease
- acoustic neuroma
neuropathic/high-stepping gait
- weakness in muscles of distal limb → peripheral nerve damage
- causes
- foot drop → common peroneal nerve injury
- L5 radiculopathy (disc prolapse)
- generalised polyneuropathy
- DM, MND, charcot-marie tooth disease
myopathic/waddling/Trendelenburg gait
- weakness of hip abductors
- systemic
- hyper/hypothyroidism
- cushing
- acromegaly
- PMR
- polymyositis or dermatomyositis
- muscular dystrophy
- DMD, becker’s MD, myotonic dystrophy
choreiform gait
- involuntary movements such as grimace/lip-smack and choreic movements
- basal ganglia disease
- huntington
- syndeham’s chorea - rheumatic fever
- cerebral palsy
- wilson’s
- dopaminergic meds (PD)
is cerebellar ipsilateral or contralateral innervating?
ipsilateral
so nystagmus going left → left cerebellum issue, same for all other signs
antalgic gait
- stand phase reduced
- caused by pain
- OA
- inflammatory joint disease
- lower limb #
- nerve entrapment e.g. sciatica
CSF features of bacteria
CSF features of virus
CSF features of GBS
CSF results of SAH
CSF results of TB
key dermatomes
- C2, C4, C7, T4, T10, L2, L5, S1
cortical issue → face + limb defect pattern
face + limb affected on same side
CNS lesion is on the contralateral
brainstem issue - face and limb presentation
- crossing signs
- contralateral facial weakness to limb weakness
- e.g. R face, left limbs
- weakness + ataxia, vertigo and double vision
Failure to abduct the eye indicts a contra lateral or ipsilateral defect of what nerves?
Ipsilateral Abducens nerve palsy (CN 6)
Describe features of Broca’s aphasia
Frontal lobe Non-fluent speech + normal comprehension + impaired repetition
cauda equina vs cord compression
describe brown sequard syndrome
ipsilateral light tough, vibration and proprioception (at lesion)
contralateral loss of pain and temperature (2-3 levels below)
how does gleason score impact prostate CA Tx
< 6 - low risk, watch and wait
7 - medium
over 7 - high risk, active treatment
what sort of kidney injury do NSAIds cause?
interstitial nephritis
cavernous sinus pathology
combination of unilateral ophthalmoplegia (cranial nerve (CN) III, IV, VI), autonomic dysfunction (Horner syndrome) or sensory CN V1- CN V2 loss.
intermittent claudication in calf - which vessel is blocked?
right superficial femoral
ophthalmoplegia + facial nerve issues
think about cavournous sinus issue
slice to hand
can’t flex MCP and PIP but can flex DIP
what structure has been damaged?
flexor digiti superficialis
