Clinical Neurophysiology

Question 1

what does an EMG investigate?

Answer 1

problems of peripheral nerve and muscle

Question 2

what does an EEG investigate?

Answer 2

electrical activity within the brain (epilepsy and altered states of consciousness)

Question 3

what do evoked potentials investigate?

Answer 3

visual and somatosensory problems in the central pathways

Question 4

what do nerve conduction studies examine?

Answer 4

nerve function: conduction velocity and amplitude

Question 5

how may myasthenia gravis affect the eye?

Answer 5

> diplopia

> ptosis

Question 6

how might you diagnose myasthenia gravis?

Answer 6

> detect antibodies
repetitive stimulation
single fibre EMG

Question 7

what does a routine EMG look at?

Answer 7

action potentials from whole motor units

Question 8

describe single fibre EMG

Answer 8

this uses a filter, sensitivity and time base settings to isolate the action potentials form individual muscle fibres within one motor unit or two fibres in the same motor unit

Question 9

normally there is little variation in the time of firing between two muscle fibres of the same motor unit. TUE OR FALSE

Answer 9

true

Question 10

what results in a jitter?

Answer 10

neuromuscular junction disease causing the tight relationship between the two fibres to be lost

Question 11

what can an EEG show?

Answer 11

> epileptic activity
state of consciousness
encephalopathy