INvestigations

Question 1

What are nerve conduction studies used for?

Answer 1

To assess peripheral nerves ofr damage

Question 2

Purpose of an MRI in motor neurone disease

Answer 2

Rule out cervical cord compression and myelopathy

Question 3

What do nerve conduction studies meaduer?

Answer 3

Speed of firing of a nerve

Question 4

What is an EMG

Answer 4

Elctromyography - electrode measures electrical activity in a muscle to assess motor neuron health

Question 5

Bedisde tests for neuro

Answer 5

Blood + urine
CK, U+Es, TFTs, ammonia
PERF/peak flow if any weakness esp global - 40-50 = normal
Lying/stnading BP is falling
Glucose

Question 6

What can raised CK suggest

Answer 6

Myositis

Question 7

Beyong neuro tests

Answer 7

ECG
CXR
CT head

Question 8

What look for in CXR in neuro

Answer 8

• horners (apical tumour), paraneoplastic synrome or cord compression, sarcoidosis, TB

Question 9

When do ECG in neuro

Answer 9

LOC/collapse,systemic muscle disease, antipscyhs etc

Question 10

When do LP in neuro

Answer 10

If drowsy or any focal neuropathy
Confirm safe to do if sus meningitis/encephalitis - danger of cerebral oedema if bleeding

Question 11

What dos T1 MRI show

Answer 11

White matter = white etc
Shows structure, abnormalities are dark

Question 12

What does T2 MRI sow

Answer 12

Photo negative
ABnormaloiteis = bright white eg infarct
Can be lost in CSF as also bright

Question 13

What does flair MRI head show

Answer 13

CSF is made dark so can identify inflam disease specifically even in areas of CSF otherwise blocked in T2

Question 14

Features of MS on MRI

Answer 14

Punk rock/dawsons fingers of corpus callosum

Question 15

LP in GBS

Answer 15

Protein high

Question 16

LP in bacterial infection

Answer 16

Increased opening pressure >30
Turbid
Increased protein
Decreased glucose <0.4 CSF:serum ratio
+ gram stain
WCC - predominantly neutrophils

Question 17

Viral infectionLP

Answer 17

Normal pressure, appearance, glucose
Normal to decreased protein
>0.6 glucose:CS ratio
WCC - lymphocytes predominant

Question 18

SAH LP

Answer 18

Increased opening pressure
Bloody, xanthrochrmic or clear CSF
Increased protein
May have increase WCC

Question 19

Why are EEGs more helpful in chidlren

Answer 19

More likely ot have abnormal EEG between events

Question 20

Demyelinating vs axonal neuropathy effect on APs

Answer 20

Dem - slows Aps, reversible
Axonal - reduces APs smaller - more permanenet - metabolic
AI cna cause both

Question 21

What see on EMG with inflammation

Answer 21

Small brief discharges with fibrillation

Question 22

What seen in MND/motor nerve loss on EMG

Answer 22

Increaed apmplitude - bigger APS
Nerve projections are dying back so remaining nerves firing mroe