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)