ACNS Guideline 9A. Guidelines on
Evoked Potentials
Intro to 2006 Guidones - answer Primary clinical application of EPs has shifted from
diagnosis of neurological disorders to monitoring during neurological, orthopedic, and
other types of surgeries to prevent neurological injury. Use of diagnostic EPs continues
and need for guidelines still present. Significant changes occur in "Recommended
Standards for Clinical Practice of EPs". Last decade has seen evolution in training and
certification examinations for interpreters.
Intro to 1991 Guidelines - answer Second version of guidelines emphasizes that
dynamic nature of field will lead to likely revision of recommendations in the future.
These revisions address some of the better-documented sources of generation of
various EP components. Visual and somatosensory EPs have undergone greatest
modification w/ relatively few changes in BAEPs. Some areas had less than total
agreement. One should feel free to deviate from guidelines when appropriate, workers
in field should know content of guidelines and understand logic behind them. Effects of
deviations should be understood. Committee discussed desirability of adding sections of
EP studies in neonates and intensive care patients, and cognitive EP, somatosensory
studies isolating function of single dorsal roots (dermatomal, segmental spinal EPs),
and MEPs. However, insufficient # of replicated reports existed to warrant inclusion at
this time. Separate report on intraoperative monitoring exists from 1984 guidelines.
Slight modifications in nomenclature of electrode location.
Intro to 1984 Guidelines - answerElectrical responses of nervous system that are time-
locked to sensory stimulus, electrical excitation, movement, or other identifiable events
are referred to as "event-related" potentials. "Evoked potential" is used more specifically
to designate responses of sensory pathways to sensory or electrical stimuli. Because of
small amplitude of EPs recorded by noninvasive methods in humans, computer
summation or averaging generally is necessary to resolve them from background
"noise". Standards recommended by the present Guidelines are limited to the following
areas:
1) Clinical practice of EPs
2) Normative studies of EPs, statistical analysis of results, and criteria for clinically
significant abnormality
3) Visual system EPs
4) Short-latency auditory EPs
5) Short latency somatosensory EPs
Standards reflect "state of the art" in clinical EP studies. Dynamic nature of this field,
revisions of recommendations will be required in some future time. No
recommendations on generator sources of individual components, or specific areas of
Evoked Potentials
Intro to 2006 Guidones - answer Primary clinical application of EPs has shifted from
diagnosis of neurological disorders to monitoring during neurological, orthopedic, and
other types of surgeries to prevent neurological injury. Use of diagnostic EPs continues
and need for guidelines still present. Significant changes occur in "Recommended
Standards for Clinical Practice of EPs". Last decade has seen evolution in training and
certification examinations for interpreters.
Intro to 1991 Guidelines - answer Second version of guidelines emphasizes that
dynamic nature of field will lead to likely revision of recommendations in the future.
These revisions address some of the better-documented sources of generation of
various EP components. Visual and somatosensory EPs have undergone greatest
modification w/ relatively few changes in BAEPs. Some areas had less than total
agreement. One should feel free to deviate from guidelines when appropriate, workers
in field should know content of guidelines and understand logic behind them. Effects of
deviations should be understood. Committee discussed desirability of adding sections of
EP studies in neonates and intensive care patients, and cognitive EP, somatosensory
studies isolating function of single dorsal roots (dermatomal, segmental spinal EPs),
and MEPs. However, insufficient # of replicated reports existed to warrant inclusion at
this time. Separate report on intraoperative monitoring exists from 1984 guidelines.
Slight modifications in nomenclature of electrode location.
Intro to 1984 Guidelines - answerElectrical responses of nervous system that are time-
locked to sensory stimulus, electrical excitation, movement, or other identifiable events
are referred to as "event-related" potentials. "Evoked potential" is used more specifically
to designate responses of sensory pathways to sensory or electrical stimuli. Because of
small amplitude of EPs recorded by noninvasive methods in humans, computer
summation or averaging generally is necessary to resolve them from background
"noise". Standards recommended by the present Guidelines are limited to the following
areas:
1) Clinical practice of EPs
2) Normative studies of EPs, statistical analysis of results, and criteria for clinically
significant abnormality
3) Visual system EPs
4) Short-latency auditory EPs
5) Short latency somatosensory EPs
Standards reflect "state of the art" in clinical EP studies. Dynamic nature of this field,
revisions of recommendations will be required in some future time. No
recommendations on generator sources of individual components, or specific areas of
