Clinical Neurophysiology Flashcards Preview

Neuro online course > Clinical Neurophysiology > Flashcards

Flashcards in Clinical Neurophysiology Deck (185):
0

what is quantitative sudomotor axon reflex testing (QSART)

test postganglionic sympathetic failure seen in small fiber neuropathies AND
excessive sweating in reflex sympathetic dystrophy

1

TEst that determines distribution of sweating?

Thermoregulatory sweat test

2

2 signs of SNS dysfunction during valsalva test?

1. exaggerated drop in BP in early phase 2 as venous return drops b/c lack of vasoconstrix
2. no overshoot of BP after relaxation due to increased venous return

3

How do you test parasympathetic function during valsalva?

You should get a reflex bradycardia as BP increases in final overshoot BP due to vagal tone. Absent in PNS dysfunction.

4

What should HR do w/ breathing and what does it test?

should increase with inspiration due to cardiovagal reflex

5

autonomic neuropathy with orthostasis, bradycardia, megaesophagus, megacolon, and congestive cardiomyopathy found in South America/Central America patients

Chagas' disease from trypanosomiasis

6

dopamine beta hydroxylase deficiency
-what does it cause in adults (2 sx)
-what NT pattern do you see
-what chromosome
-what tx?

Increased dopamine, lack of NE
chromosome 9q34
causes ptosis, orthostatic hypotension
tx: L-DOPS which can be decarboxylated into NE instead

7

Dopamine hydroxylase deficiency causes what in neonates?

3Hys: hypothermia, hypoglycemia, hypotension episodes

8

Disease with hypohidrosis, decreased tear/saliva, GI dysmotility, impotence, severe lancinating pain in extremities, renal disease
Cause
Genetics?

Fabry's
alpha galactosidase def
X-linked recessive

9

What is familial amyloid polyneuropathy caused by and what is the disease path and sx?

small fiber neuropathy due to transthyretin defect FAP1
causes pain/temp sensation loss, autonomic sx and CHF

10

Disease causing lack of sensitivity to pain?

Hereditary sensory and autonomic neuropathies (HSAN) particularly
Riley-Day syndrome: HSAN III autosomal recessive in Ashkenazi jews (familial dysautonomia)

11

Genetic cause of Riley Day?

autosomal recessive mutation in kappaBkinase complex assoc protein on chrom 9q31

12

Distinctive feature of Riley day? (2 sx/si)

absence of fungiform papillae on tongue and no overflow emotional tears

13

EEG frequencies: the order from slow to fast

Delta, Theta, Alpha, Beta
*Dig that awesome beat

14

Alpha freq EEG?

8-13

15

Theta freq EEG

4-7

16

Beta freq EEG

>13

17

Delta freq EEG

<4

18

negative deflection on EEG means what

That the first input is positive compared to second
(pos to neg is down)

19

What is the layout of bipolar montage?

inputs 1 and 2 are adjacent:
Channel 1: Fp1-F3
Channel 2: F3-C3
Channel 3: C3...

20

What is a referential montage?

There is a reference electrode that is presumably inactive
Channel 1: Fp1-Cz
Channel 2: F3-Cz
Channel 3: C3-Cz

21

Hyperventilation shouldn't be performed w/ EEG on which 3 (non resp dz)

1. cerebrovascular dz
2. sickle cell trait/dz
3. moymoya

22

Normal EEG response to hypervent?

generalized background slowing

23

photic response w/ epileptiform discharges seen in what major epilepsy? Actual photoconvulsive response seen with what?

JME (photoparoxysmal response)
primary generalized epilepsy - pts can have seizure w/ photic

24

Background rhythm norms at 3 mos and 5 mos?

3 mos: 3 HZ
5 mos: 5 Hz

25

background alpha rhythm of at least 8HZ by what age?

3 yr

26

What is a kappa wave in EEG and when does it occur?

low amplitude in temporal regions, either alpha or theta during THINKING (phi beta kappa)

27

what is lambda waves and when do you seen them?

positive sharp transients in occipital area during visual scanning (if you are looking around at a bunch of lambs)

28

What is the mu rhythm
where and when does it occur?

arciform 7-11 Hz in centroparietal regions, attenuated by moving or thinking about moving the contralat body

29

spikes seen 6-11 hz in temporal region, during drowsy/light sleep in adults?

wicket spikes/waves

30

delta activity in kids/adol w/ overriding alpha that attenuates with eye opening

posterior slow waves of youth

31

WHo gets 14 and 6 positive bursts of arciform activity over posterior temporal for < 3 sec and when?

adolescents in light sleep

32

What do you see in teens/adults with wakefulness and drowsiness that disapper with sleep?

bursts of diffuse 6hz very small spike and higher amplitude wave discharges for a couple of seconds (phantom spike/wave)

33

What are small sharp spikes of sleep in adults

brief low voltage (<50mv) spikes over temporal region in drowsy/light sleep: small sharp spikes of sleep

34

5-7 Hz sharp countoured theta in bursts over temporal region in drowsy young adults

rhythmic temporal theta bursts of drowsiness/psychomotor variant pattern

35

WHat are the two types of alpha coma?

1. posterior dominant alpha: poorly reactive: pontine strokes/brainstem lesions
2. diffuse frontal alpha: poorly reactive: after anoxia

*Alpha coma: anoxia/arrest

36

what is bancaud's phenomenon

when alpha activity over one hemisphere doesn't attenuate w/ eye opening (non reactive hemisphere is abnormal)

37

What causes beta coma

Bzd, Barbs: better buzzed encephalopathy or brainstem lesion
high amplitude generalized beta

38

What rhythm on EEG with skull defect with higher amplitude spiky looking EEG activity?

Breach rhythm

39

What causes focal delta activity on EEG

continuous and polymorphic delta due to structural lesion

40


define spike on EEG?

< 70ms

41

define sharp wave on EEG

70-200msec

42

WHat is FIRDA? and what does it mean?

Frontal Intermittent Rhythmic Delta Activity
seen in encephalopathy, incr ICP. deep midline lesions

43

What is pattern do you see in kids with encephalopathy instead of FIRDA?

Occipital (OIRDA)

44

WHat are PLEDS and what causes them?

Sharp activity at regular intervals over a hemisphere
usually from stroke or Herpes encephalitis

45

What are triphasic waves?

frontal dominant waves with an anterior to posterior lag seen in hepatic encephalopathy and others

46

What EEG findings can Clozapine cause?

Clozapine: clonic activity:
Interictal discharges, GTCs, myoclonus

47

Two meds that can cause seizures in people w/o epilepsy?

Bupropion (Wellbutrin) and DEmorol (meperidine) OD

48

Two meds that can cause seizures in patients with epilepsy and one med that causes interictal discharges in patients w/ epilepsy?

Seizures: Ultram (tramadol) and Benadryl
Discharges: Lithium

49

Sharp or sharp/slow wave complexes every 1-3 sec and PLEDS?
What dz?

herpes encephalitis

50

EEG showing high amplitude periodic sharp wave complexes every 4-15 seconds generalized occurs in what stage of post-measles?

subacute sclerosing panencephalitis, stage 2.

51

Stages of SSPE (post measles)

I: personality change/lose academics
II: EEG findings, myoclonic jerks, cognitive decline
III: stupor, EPS, autonomic sx, hyperreflexia, rigidity
IV: chronic vegetative state

52

generalized periodic sharp wave complexes every 0.5-1.6 seconds in what disease

CJD NOT variant (mad cow)

53

EEG criteria for brain death? (7)

1. 8 electrodes
2. 2microvolt sensitivity
3. electodes at least 10cm apart
4. impedance 100-5000 ohms
5. low freq filter set < 1Hz
6. high freq filter set >30 Hz
7. Duration 30 min

54

QUiet and active sleep in neonates is found when and what are the stages like?

between 30-36wk
active: like REM (go straight to it)
quiet: similar to nonREM, less synchrony than in younger babies

55

What is active moyenne in neonatal EEG?

appears at 36 wks and is a continuous pattern of mixed freq during awake and active sleep (REM sleep)

56

EEG development in quiet sleep in neonate?

TD (trace discontinu) -->TA (trace alternans) -->CSWS (continuous slow wave sleep) -->CSWS and spindles

Active sleep - awake - quiet sleep.

57

What is a CMAP represent?

the sum of all the individual muscle fiber action potentials

58

Draw the CMAP and label the parts

latency: time from stimulus to initial CMAP
amplitude: peak of wave
duration: length of time on x axis from when waves return to original start before overshoot

59

What does latency reflect?

fastest conducting motor fibers

60

What does amplitude reflect?

number of muscle fibers

61

what does duration reflect on EMG?

synchrony of muscle fiber firing

62

what would a significant drop in area comparing CMAPs with distal and proximal stimulation suggest?

a conduction block

63

Do you see a conduction block in acquired vs inherited demyelinating polyneuropathies

only in acquired.

64

what do you see in multifocal motor neuropathy with conduction block?
Marker?

you see conduction blocks in sites w/o compression, asymmetric weakness and atrophy beginning distally.
Marker is anti-GM1 antibodies

65

What is a martin gruber anastomosis? what does it look like?

when recording from abductor digiti minimi, shows apparent conduction block between wrist and below elbow during ulnar motor studies
-from fibers crossing median nerve to innervate some muscles usually innervated from ulnar nerve

66

How does low temp affect EMG?

increased latency, duration, amplitude, area of motor and sensory action potentials

67

What do you use to measure the conduction velocity with regards to latency

onset latency (not peak latency) / distance from stimulation point

68

what does EMG/NCS show in small fiber neuropathies

its normal

69

EMG findings in demyelinating neuropathy?

1. prolonged distal latency
2. normal/reduced amplitude
3. reduced conduction velocity by about 50%
4. conduction block
5. increased temporal dispersion

70

EMG findings in axonal neuropathy

1. decreased amplitude
2. only mild slowing

71

if you have loss of sensation but normal sensory nerve action potentials, where is the lesion?

proximal to the DRG

72

if you have loss of sensation and lost SNAP, where is lesion?

plexus

73

what is more sensitive test for picking up carpal tunnel on EMG?

median nerve palmar sensory response b/c routine NCS may be normal

74

What is the F response and what does it mean?

late response when the AP travels back in the antidromic direction to the anterior horn cell via ventral root and then back down the motor nerve *shows integrity of the proximal motor neuron pathway)
F responses are in motor only, not sensory neurons

75

Earliest GBS finding on EMG/NCS?

loss of F response

76

What is the H reflex and what does it mean?

monosynaptic reflex involving alpha motor neurons: stimulate tibial nerve w/ submaximal stimulus in popilteal fossa and record in gastroc/soleus
tests integrity of proximal sensory and motor pathways

77

compare/contrast H reflex and F response

H reflex: involves synapse adn mixed nerves
F response: motor nerves only: no sensory or synapse

78

What is increased or decreased insertional activity on EMG?

waveform lasting more than 200msec when you insert needle.
Seen in neuropathic denervation and myopathic polymyositis

Decreased insertional activity is seen when muscle is replaced by fat/CT

79

What are fibrillation potentials on EMG

from single muscle fiber

80

Best test for NMJ d/o?

single fiber EMG

81

Repetitive nerve stim test used for what?

NMJ d/o of myasthenia, LEMS, botulism

82

What do you see on Repetitive nerve stim in LEMS and Myasthenia and Botulism?

CMAP decrement at 2-5 HZ with LEMS and MG
CMAP increment at 20-50Hz w/ LEMS and botulism

83

What is neurapraxia?

nerve injury with loss of conduction but axon intact: conduction block with proximal stimulation

84

What is axonotmesis?

axon disrupted but sheat intact in axonotmesis: failure to conduct and wallerian degeneration of part of axon removed from cell body

85

What is neuronotmesis?

axon and connective tissues disrupted: most severe injury

86

Peaks in BAERS? What is most prominent?

NCSLIMA:
Nerve, cochlear nuclei, superior olivary complex (pons), lateral lemniscus (pons), inferior coliculus (mb), MGN (thal), auditory radiations (thalamocortical)
Waveform V: inferior colliculus should be most prominent

87

What is delayed in VEPs for lesion anterior to optic chiasm?

p100

88

Somatosensory evoked potentials (SSEPS) what are N9, N11, P14, N18, N20 of median nerve?

N9: erb's point, brachial plexus
N11: cervical cord
P14: caudal brainstem
N18: upper brainstem
N20: primary somatosensory cortex

89

What are median nerve SSEPs useful for?

to identify lesion in dorsal column medial lemniscal system
*ie p14-N20 latency suggests defect conduction between brainstem and cortex

90

Tibial nerve SSPEs? N8, N19, N22, P31, N34, P38

N8: tibial nerve
N19: cauda equina
N22: lumbar gray matter
P31: medial lemniscus
N34: multiple brainstem
P38: primary somatosensory cortex

91

Neurotransmitters that promote wakefulness?

NE, Histamine, Dopamine, Serotonin
(and ACh is also increased in wakefulness (and REM())

92

WHat neurons promote wakefulness? from where?

orexin/hypocretin neurons in posterior/lateral hypothal

93

What NT promotes sleep and what blocks it?

Adenosine: receptors blocked by caffeine and theophylline

94

what neurons important for sleep onset?

basal forebrain and anterior thalamus

95

What helps with initiation of sleep?

inhibition of hypocretin By GABA from preoptic and basal forebrain neurons

96

VErtex waves seen in what stage of sleep

Stage 1: with slowing of background

97

Stage II sleep characterized by onset of what?

sleep spindles and K complexes

98

What parts of sleep are characterized by NREM vs REM

NREM in beginnning 1/3, REM in last 1/3

99

What is hypnagogic and hypnopompic hypersynchrony?

bursts of synchronous theta/delta in children mostly during drowsiness

100

What are POSTS and when are they seen?

positive occipital sharp transients in occipital region looking like checkmarks in runs occur in drowsiness and light sleep, max in adolescents

101

What can elicit K complexes during sleep?

noise

102

Sawtooth waves and theta frequency waves in brief runs found in frontocentral region in what?

REM sleep

103

When do sleep spindles and vertex waves appear in stage II sleep in babies?

spindles by 2 mos
vertex by 3-4 mos, well formed at 5 mos

104

In adulthood, what perentage of time in each stage of sleep?
Elderly?

1 <5%
2. 40-60%
3/4. 10-20%
REM: up to 25%
Elderly: increase stage 1, decrease slow wave

105

WHen do nightmares occur (stage of sleepP)

REM

106

When do confused arousals and night terrors occur in sleep?

slow wave sleep

107

when do periodic limb movements occur in sleep?

light sleep stage 1-2

108

When does sleep walking occur in sleep?

slow wave sleep

109

So what half of sleep due sleep walking, terrors, confused arousals present in?

1st half

110

WHat is periodic limb movement disorder?

> 5 PLMS / hour of sleep, PSN diagnosis *not clinical

111

When do periodic limb movmeents occur in sleep?

light sleep

112

Hypnagogic vs hypnopompic hallucinations

gogic: when goes to sleep
pompic: when wakes

113

What biochemical test is abnormal in people with narcolepsy

low CSF orexin/hypocretin

114

what bug causes sleeping sickness?

african trypanosomnias from trypanosoma brucei (tse tse fly)

115

when is peripheral myelination complete?

by age 3-5y. conduction velocity should be same as adults

116

What is the deal with height and conduction velocity and what is most affected?

Taller --> slower CV
affects the F waves

117

what are two stimulation errors?

1. submaximal stimulation (large fibers have highest threshold and are evoked last)
2. costim of adjacent nerves leading to too large amplitudes

118

what fibers are measured in nerve conduction studies?

large myelinated fibers

119

Basic neuropathic patterns of NCS? (2) and how they are differentiated?

1. axonal loss: reduced amplitude, basically normal conduction velocity and distal latency
2. demyelination: marked slowing of conduction velocity (<30-35) and markedly prolonged distal latency

120

what does temporal dispersion indicate and what else happens with wave forms? when is this most prominent?

Demyelination b/c slow fibers lag behind fast ones, can cause amplitude to drop by >50% too.
More prominent with sensory than motor and proximal stimulation

121

What do you see in conduction block?
What is definitely indicative of conduction block?

drop in CMAP of at least 20% and increased duration of at least 15%. Area drop of at least 50% is definite conduction block

122

myokymic discharges seen in what?

post radiation plexopathy (pathognomonic)

123

what makes a hissing or seashell noise on EMG needle study due to small monophasic negative potentials?

end plate noise near NMJ - normal

124

what makes a fat in the frying pan sound on needle EMG that is negative deflections and irregular?

end plate spikes

125

What makes a rain sound with positive regular deflections (downward)

fibrillations on needle EMG

126

What do you see EMG fibrillations in? (4)

1. neuropathic disorders
2. inflammatory myopathies
3. muscular dystrophies
4. botulism

127

What kind of spontaneous needle EMG activity do you see in active denervation?

positive waves from spontaneous depolarization of muscle fiber, regular pattern making dull pop

128

regular rain on roof needle EMG sound with downward (positive) deflections

fibrillations

129

what are myotonic discharges and what are they seen in most commonly?

spontaneous d/c of muscle fiber with waxing/waning pattern, similar to p waves with brief positive spike. Revving engine sound in myotonic dystrophy but many others

130

what dx with eyelid, arm, leg, feet, tongue fasciculations but otherwise normal exam, some cramping

benign fasciculation syndrome

131

3 conditions assoc w/ myokymia

1, radiation injury
2. facial myokymia in GBS, MS, pontine tumors
3. low serum Calcium

132

needle EMG pattern for neuropathy vs myopathy?

neuropathy: decreased recruitment, large amp Motor unit APs

myopathy: early recruitment of small, polyphasic units

133

What three nerves come off of the first half of the brachial plexus, supraclavicular portion and what are they made of?

1. dorsal scapular from C5 root only
2. suprascapular from C5 and C6 upper trunk
3. long thoracic from C5 C6, C7

134

WHat are the two divisions of the sciatic nerve and what do they innervate?

tibial: semiteninous, semimembranous biceps femoris long head;
Peroneal: biceps femoris short head

135

major role of obturator and root supply?

adduction of lower extremity
L2-4

136

major action and root supply of femoral nerve?

hip flexion, knee extension L2-4

137

What is the dx and tx for acute onset shoulder and arm pain then weakness and sensory loss w/ no trauma hx?

parsonage turner, neuralgic amyotrophy

138

subacute onset of weakness and atrophy of pelvic and femoral muscles with lots of hip / thigh pain, absent patellar reflexes
Dx and course?

diabetic amyotrophy, gradual recovery over 6 mos

139

median nerve mononeuropathy with what sx?

LOAF weakness and atropy, numbness in digits 1-3.5
LOAF: lumbricals 1/2, opponens pollicis, APB, FPB

140

most common radial neuropathy
causes what, spares what?

spiral groove causes wrist drop, spares ticeps

141

nerve responsible for foot eversion?

tibial

142

NMJ presynaptic EMG and repetitive stim findings?

facilitation of CMAP amplitudes after exercise and high freq (30HZ) stim
-may have p waves / fibs
(LEMS, Botulism)

143

EMG rapid stim findings in post synaptic NMJ dz/

>10-20% decrement after exercise, unstable MUAP on EMG needle study

144

what characterizes juvenile absence seizures

1. absence on wakening
2. myclonic sz
3. EEG 3-5HZ

145

myoclonus in AM, GTCs, college student? Dx and tx?

JME, VPA

146

EEG w/ symmetric, bilateral polyspike generalized spike/wave complexes 4-6Hz, maximal at frontal, and photosensitivity

JME

147

slow spike and wave < 3Hz discharges
Dx and tx?

LGS, lamotrigine, VPA, VNS

148

post traumatic epilepsy
% w/ sz at 6 mos, and at 2 yrs

50% at 6 mos, 80% at 2 y
(75% remain sz free after 1yr, 90% after 2 yrs)

149

Best associated with poor outcome after cardiac arrest? evoked potential?

median SSEP N20 (Thalamocortical radiations)

150

absence of wave V on brainstem auditory evoked potential?

lesion of auditory pathway above caudal pons (lateral lemniscus/inferior colliculus)

151

what exactly does EEG measure

voltages between electrodes on scalp. Detects extracellular currents of large groups of radially oriented pyramidal cells in cortex

152

yield of single routine EEG to be abnormal in pt w/ epilepsy
1 vs 4 and w/ sleep

1 50%
4 92%
w/ sleep 80%

153

Evoked Potentials, examples of near vs far fields

near: near the recording electrode w/ restricted distribution
(P100, Wave I, N20)

Far: recorded further from source, Waves II-V of BAERS

154

What is the order of the VEP waves and what do they represent (2 main)

N75 is the turn at the Meyers loop of radiations after LGN
P100/N100 is the calcarine fissure/visual cortex

155

Reduced P100 amplitude indicates what

ocular or retinal lesion (think of half as much light getting in)

156

Increased P100 latency and decreased amplitude is due to what

usually demyelinating optic neuropatphy like optic neuritis

157

Pattern on VEP expected in acute optic neuritis

loss of P100

158

expected VEP with anterior ophtho pathway compressive lesion

abnormal P100 morphology AND latency

159

expected VEP with ischemic or toxic optic neuropathy that isn't necessarily demyelinating

P100 amplitude diminished (axon damaged, myelin isn't)

160

6 stops of the auditory pathway mnemonic

CNS LIMA:
Cochlea --> Nerve/Nucleus VIII --> Superior olive -->Lateral lemniscus --> Inferior colliculus --> MGN --> auditory cortex

161

5 Waves of BAERS and three most important and what they represent

*I: distal CN VIII / spiral ganglia
II: proximal nerve/cochlear nucleus VIII
*III: superior olive or ventral pons
IV: upper pons - inferior lateral lemniscus in pons
*V: inferior Colliculus MIDBRAIN

162

IF BAERS are absent bilaterally?

technical, braindeath, or bilateral CN VIII lesions

163

absent unilateral BAERs

think CNVIII or cochlear lesion

164

BAERS:
One side normal
Other side only peak 1

CP angle lesion affecting rest of signal

165

BAERS
increased wave I latency, normal waves the rest

peripheral hearing loss or partial CN VII lesion

166

BAERS Increased latency of waves I-III, rest are normal

lower brainstem lesion

167

BAERS w/ delayed latency waves III-V

upper brainstem lesion

168

Somatosensory evoked potentials do what?

measure integrity of the dorsal column pathway by stimulating median or tibial nerve and assessing potentials in spine and scalp

169

What are the waves for median nerve SSEP?

N9: plexus / Erb's point
N13: cervical cord / DRG
N18: Brainstem
**N20: primary somatosensory cortex: most prognostic
P22: cortical positivity after N20

170

Tibial SSEPs

PP/PF: popliteal fossa
N22: lumbar spine
P31: cervical medullary cunction
N34: brainstem
P37: primary somatosensory cortex

171

Absent N20 suggests what?

poor prognosis in hypoxic ischemic coma

172

On Nerve conduction study:
What is the F wave and what does it represent
Is there a synapse
When is it abnormal?

measure from ANY motor nerve with supramaximal stimulus and look at backfiring responds
reflects conduction along the entire length of the motor nerve (proximal)
Does NOT involve synapse
Abnormal early in demyelinating neuropathies

173

In NCS what is the H reflex
what does it represent
synapse?
equivalent of what clinically
where is it measured

Measured only in the tibial nerve
it measures a REFLEX arc with sensory and motor and a synapse (monosynaptic in cord)
Reflects conduction along sensory nerve and motor nerve
Equivalent of subtle ankle jerk

174

If you lose axons what basically happens on the nerve conduction study?

you reduce the amplitudes of the CMAP and SNAP
perhaps slightly decrease the Conduction velocity only because you may lose the fastest ones
You NEVER see conduction block or abnormal temporal dispersion

175

What do you basically see on Nerve Conduction Study in Demyelination?

You see massively reduced conduction velocity with prolonged distal motor latencies and F wave latencies

You may see conduction block and/or temporal dispersion if acquired

176

What does conduction block look like on NCS?

If partial, you see Massively diminished amplitude and area under the curve in proximal compared to distal areas

177

What does temporal dispersion look like on Nerve conduction study?

increased duration of the CMAP

178

What is a motor unit

the motor neuron and all the muscle fibers it supplies

179

What is a motor unit action potential

summation of fraction of muscle fiber action potentials of that motor unit, at recording electrode tip (8-20 muscle fibers)

180

Motor unit action potential height is increased in what and decreased in what

increased in neurogenic disorders with axonal collateral sprouting and decrease in myopathic disorders when just can't get enough force

181

motor unit action potential is increased in what and decreased in what

increased in neurogenic disorders w/ axonal collateral sprouting and severe chronic myopathies

decreased in myopathic disorders or severe disorders of NMJ

182

recruitment is reduced in what and increased in what conditions on EMG

decreased in neurogenic
increased in myopathic: abnormally increased early recruitment

183

the non "Myotonia" clinical condition that can have myotonic discharges on EMG

hyperkalemic periodic paralysis

184

generalized myokymia is seen in what
limb myokymia is seen in what
face myokymia is seen in what

Isaac's syndrome
facial in brainstem lesions
limb in radiation plexopathies