Electrodiagnostic Studies Flashcards
What 3 abnormal spontaneous activities seen on EMG arise from motor unit pathology
- Fasciculations
- Myokymic discharges
- Neuromyotonic discharge
What happens to SNAP in ALS
Normal
Amplitude of fibs and PSWs
Fibs = ~300 microvolts PSWs = ~1000 microvolts
What is the initial deflection of myotonic discharge
Varies - can be positive deflection or biphasic or triphasic
What 2 muscles can you use for H-reflex
FCR and gastroc-soleus
what type of neuropathy is seen in diabetic neuropathy
axonal and demyelinating sensory motor neuropathy
Normal amplitude of a MUAP
1 mV
what is the correlation between firing frequency and recruitment pattern
increased firing frequency = decreased recruitment
Are large amplitude long duration MUAPs seen in myopathic or neuropathic processes
Neuropathic
Normal duration of a MUAP
5-15 ms
Are short duration small amplitude MUAPs seen in myopathic or neuropathic processes
Myopathic
in the newborn, nerve CV are what percentage of adult values
50%. 1 yo = 75% of adult values
What denervation potential sounds like dive bomber
Myotonic discharge
what type of neuropathy is seen in alcohol neuropathy
axonal sensory motor neuropathy
SSEPs only evaluates nerve fibers that sense _________ and __________
Vibration and proprioception