Y4 Neurology

Question 1

describe the transmission of an AP to create muscle contraction?

Answer 1

1. Presynaptic voltage-gated Ca2+ channels open → Ca2+ influx
2. ACh vesicles released from presynaptic terminal
3. ACh diffuses across cleft
4. ACh binds to nicotinic receptors on post-synaptic
   terminal
5. → Na+ influx → depolarisation → Ca2+ release from SR
   → muscle contraction
6. ACh is degraded by acetylcholinesterase and choline is
   taken up into presynaptic terminal.

Question 2

what receptor does ACh bind to at the post synaptic terminal of the NMJ?

Answer 2

nicotinic

Question 3

what blocks ACh vesicle fusion at the NMJ?

Answer 3

botulinum, LEMS

Question 4

what blocks nicotinic ACh receptors at the NMJ?

Answer 4

Non-depolarising: atracurium, vecuronium 􏰁

Depolarising: suxamethonium

Question 5

what three conditions are associated with dopamine pathways?

Answer 5

schizoaffective disorder
parkinsons
hyperprolactinaemia

Question 6

what dopamine pathways in the brain are associated with schizoaffective disorder?

Answer 6

Mesocorticolimbic: SCZ

Question 7

what dopamine pathways in the brain are associated with parkinsons ?

Answer 7

􏰀 Nigrostriatal: Parkinsonism

Question 8

what dopamine pathways in the brain are associated with hyperprolactinaemia ?

Answer 8

􏰀 Tuberoinfundibular: Hyperprolactinaemia

Question 9

what symptoms would you expect from a cortical lesion?

Answer 9

Hyperreflexia proximally in arm or leg

􏰀 Unexpected patterns

Question 10

what symptoms would you expect from a cord lesion ?`

Answer 10

Quadriparesis / paraparesis

􏰀 Motor and reflex level: LMN signs at level of lesion and UMN signs below

Question 11

what symptoms would you expect from a internal capsule lesion?

Answer 11

Contralateral hemiparesis ̄c pyramidal distribution.

Question 12

where is the lesion with fasciculations?

Answer 12

LMN

Question 13

where is the lesion for brown sequard syndrome?

Answer 13

hemi spinal cord

Question 14

what are the symptoms of brown sequard syndrome ?

Answer 14

Ipsilateral loss of proprioception / vibration and UMN weakness with contralateral loss of pain

Question 15

what symptoms are seen in cerebellar syndrome?

Answer 15

Dysdiadochokinesia
􏰀 Dysmetria: past-pointing
􏰀 Ataxia: limb / trunkal
􏰀 Nystagmus: horizontal = ipsilateral hemisphere
􏰀 Intention tremor
􏰀 Speech: slurred, staccato, scanning dysarthria
􏰀 Hypotonia

Question 16

what are some common causes of cerebellar syndrome ?

Answer 16

Paraneoplastic: e.g. from bronchial Ca
􏰀 Alcohol: thiamine and B12 deficiency
􏰀 Sclerosis
􏰀 Tumor: e.g. CPA lesion
􏰀 Rare: MSA, Friedrich’s, Ataxia Telangiectasia
􏰀 Iatrogenic: phenytoin
􏰀 Endo: hypothyroidism
􏰀 Stroke: vertebrobasilar

Question 17

what visual disturbance is seen with posterior cerebral artery occlusion?

Answer 17

Contralateral homonymous hemianopia ̄c macula sparing.

Question 18

what is the vascular cause of lateral medullary syndrome?

Answer 18

occlusion of one of the PICA arteries

Question 19

what is ataxia?

Answer 19

The term ataxia refers to a lack of fine control of voluntary movements.

Question 20

what does lateral medullarly syndrome result in?

Answer 20

􏰁 Dysphagia
􏰁 Ataxia (ipsilateral)
􏰁 Nystagmus (ipsilateral) 􏰁 
Vertigo
􏰁 Anaesthesia
- 􏰂 Ipsilat facial numbness + absent corneal reflex
􏰂-  Contralateral pain loss
􏰁 Horner’s syndrome (ipsilateral)

Question 21

what symptoms does Millard-Gubler Syndrome have ?

Answer 21

Effects: 6th and 7th CN palsy + contralateral hemiplegia

Question 22

what causes Millard-Gubler Syndrome?

Answer 22

Pontine lesions

Question 23

what are the effects of an anterior spinal artery occlusion? (Becks syndrome)

Answer 23

Para- / quadri-paresis
􏰁 Impaired pain and temperature sensation
􏰁 Preserved touch and proprioception

Question 24

what does LEMS stand for?

Answer 24

Lambert-Eaton myasthenic syndrome

Question 25

where does LEMS affect?

Answer 25

the NMJ

Question 26

what can cause peripheral neuropathy?

Answer 26

DM, EtOH, uraemia

Question 27

what can cause damage to the dorsal columns?

Answer 27

B12 deficiency

Question 28

what is lost when the dorsal columns are damaged ?

Answer 28

proprioception