Neurology Formative Flashcards Preview

Neurology > Neurology Formative > Flashcards

Flashcards in Neurology Formative Deck (50)
Loading flashcards...
1
Q

what are the 2 divisions of the corticospinal tract?

A
lateral
- motor control of limbs and digits
- decussates in pyramids
ventral
- motor control of trunk and posture
- decussates segmentally
2
Q

function of corticobulbar tract?

A

type of descending pyramidal tract

controls muscles of face, head, neck (contains UMNs of CNs)

3
Q

how can a central/peripheral lesion affecting corticobulbar tract be differentiated?

A

central = forehead sparing

- corticobulbar tract gives bilateral innervation to CN nuclei apart from CNs 12 and lower 7 (which innervates forehead)

4
Q

what are the 2 non-pyramidal descending tracts?

A

rubrospinal

reticulospinal

5
Q

origin and function of rubrospinal tract?

A

originates in red nucleus of midbrain
excites flexor muscles of upper limb and inhibits extensor muscles
(doesn’t innervate lower limb)

6
Q

origin and function of reticulospinal tract?

A

originates in pons/medulla

excites flexors

7
Q

what is decorticate rigidity?

A

posture caused by damage to nerves between brain and spinal cord
flexed plantars, internally rotated legs, flexed arms and wrists
adducted arms

8
Q

what is decerebrate rigidity?

A
posture caused by midbrain lesion
flexed plantars
extended and pronated arms
flexed wrists
adducted arms
9
Q

what are the 2 divisions of the dorsal column and what does each carry?

A

cuneate fasciculus = from arm

gracile fasciculus = from leg

10
Q

neurones in dorsal column pathway?

A
1st = site of excitation > dorsal root ganglion
2nd = dorsal root ganglion > spinal cord > thalamus
3rd = thalamus > post central gyrus
11
Q

neurones in spinothalamic tract pathway?

A
1st = site of excitation > dorsal root ganglion
2nd = decussates and ascends spinal cord to thalamus
3rd = thalamus > post central gyrus
12
Q

what causes central cord syndrome?

A

damage to medial fibres in spinal cord
usually due to hyperflexion or extension in an already stenotic neck
common in elderly
can be due to syringomyelia (fluid filled cavity in spine) in younger people

13
Q

features of central cord syndrome?

A

loss of spinothalamic sensation in cape distribution
mainly upper limb signs
- distal weakness, tingling/numbness
normal lower limbs and dorsal column sensation

14
Q

what is anterior cord syndrome?

A

compression of anterior spinal artery causing anterior cord ischaemia

15
Q

features of anterior cord syndrome?

A

dorsal column intact

complete motor paralysis and loss of spinothalamic sensation below lesion level

16
Q

features of brown sequard syndrome?

A

ipsilateral dorsal column and corticospinal dysfunction

contralateral spinothalamic dysfunction

17
Q

common cause of brown sequard syndrome?

A

stab wound to back

18
Q

where is the circle of willis found?

A

subarachnoid space

19
Q

where are dural venous sinuses found?

A

between periosteal and meningeal dural layers

20
Q

main cause of extradural haemorrhage?

A

rupture of middle meningeal artery due to head trauma

common in younger people and boxers

21
Q

presentation of extradural haemorrhage?

A

punched on side of head, lost consciousness but was fine straight after but then unconscious 4 hours after
“lucid interval”

22
Q

imaging findings of extradural haemorrhage?

A

hyperdense biconvex lens appearance

23
Q

cause of chronic subdural haemorrhage?

A

rupture of cerebral bridging veins

common in elderly after a fall (low impact trauma)

24
Q

presentation of chronic subdural haemorrhage?

A

progressive headache and confusion weeks after a fall

25
Q

imaging findings in chronic subdural haemorrhage?

A

hypodense crescent shaped appearence

26
Q

cause of subarachnoid haemorrhage?

A

rupture of berry aneurysm in circle of willis due or severe head injury

27
Q

presentation of subarachnoid haemorrhage?

A

severe thunderclap headache
meningeal irritation
loss of consciousness

28
Q

imaging findings in subarachnoid haemorrhage?

A

hyperdense signal in subarachnoid space

29
Q

where does blood accumulate if each vessel ruptures?

  • bridging cerebral vein
  • posterior communicating artery
  • middle meningeal
A

bridging = subdural
posterior communicating = subarachnoid
middle meningeal = extradural

30
Q

general features of cerebral herniation?

A

extensor response
UMN signs
cushings triad
unreactive pupils

31
Q

what is cushings triad?

A

hypertension
bradycardia
irregular breathing

32
Q

what type of herniation is most associated with unreactive, blown pupul?

A

uncal herniation

inner aspect of temporal lobe herniates, compressing CN III

33
Q

what is Hoffman’s sign?

A

where flicking/tapping of the middle finger produces twitching/flexing of the index finger to thumb
sign of UMN lesion

34
Q

Babinski reflex?

A

where stimulation of the sole of the foot causes upward flexion of the big toe
indicates UMN lesion

35
Q

anterior circulation in brain?

A

internal carotid via carotid canal > ophthalmic (to eyes) > middle cerebral and anterior cerebral arteries
- anterior communicating artery between anterior cerebral arteries

36
Q

posterior circulation in brain?

A

posterior inferior cerebellar artery, anterior inferior cerebellar artery and superior cerebellar artery supply cerebellum
pontine artery branches off basillar artery
posterior communicating artery forms edges of circle of willis

37
Q

features of total anterior circulation stroke?

A

all 3 of

  • higher cerebral dysfunction
  • homonymous visual field defect
  • contralateral motor and/or sensory deficit of at least 2 areas (face/arm/leg)
38
Q

partial anterior circulation stroke?

A

2 of:

  • higher cerebral dysfunction
  • homonymous visual field defect
  • motor and/or sensory deficit in at least 2 areas (face/arm/leg)
39
Q

features of posterior circulation stroke?

A

cerebellar dysfunction
isolated homonymous visual field defect
cranial nerve dysfunction

40
Q

features of lacunar stroke?

A

pure motor or pure sensory stroke

common in longstanding cerebrovascular disease and risk factors (Smoking etc)

41
Q

site and function of broca’s area?

A

inferior frontal gyrus
formulating language
- expressive dysphasia if damaged

42
Q

site and function of wernickes area?

A

superior temporal gyrus
language comprehension
- receptive/Wernicke’s dysphasia if damaged

43
Q

function of parietal lobes?

A

writing
calculations
dressing self

44
Q

where is the auditory complex?

A

superior temporal gyrus

45
Q

3 main features of cerebellar dysfunction?

A

nystagmus
dysarthria
intention tremor

46
Q

classic history of cerebellum tumour?

A

children
progressive headache
wide based ataxia
difficulty speaking

47
Q

a lesion where cause left superior quadrantanopia?

A

right temporal lobe

48
Q

what is gerstmann syndrome?

A

specific symptoms caused by dominant parietal lobe lesion

  • inability to write
  • inability to do mathematics
  • inability to distinguish own from another person’s fingers
  • inability to distinguish left from right side of body
49
Q

which types of hydrocephalus is most common in children and what usually causes this?

A

non-communicating

aqueduct stenosis

50
Q

how does non-communicating hydrocephalus present in children?

A

large head
retracted eyes
sunsetting of eyes
impaired upward gaze