Ocular artifacts
in EEG recordings have distinguishing features that differentiate them from
other EEG patterns and artifacts.
Nature of Ocular
Artifacts:
o Ocular artifacts
are primarily caused by movements and electrical activity associated with the
eyes.
o These artifacts
can result from various eye movements, including blinks, eye flutter, lateral
gaze, and rapid eye movements (REMs) of REM sleep.
2. Characteristics:
o Ocular artifacts
typically manifest as slow waves or rhythmic activity that is limited to the
frontal regions.
o The waveform of
ocular artifacts can resemble delta activity but does not extend into the
central region.
o The amplitude and
duration of ocular artifacts are related to the rate and duration of eye
movements, with a steep decline in amplitude with distance from the orbits.
3. Differentiation:
o Ocular artifacts
can be distinguished from epileptiform discharges by waveform differences and
field distribution, with ocular artifacts typically having a sharper contour
and more limited field.
o Using specific
electrode configurations, such as supraorbital and infraorbital electrodes, can
aid in definitively differentiating ocular artifacts from other patterns.
o The presence or
absence of eye movements, as noted by the technologist, can also help
differentiate ocular artifacts from other EEG patterns.
Understanding the
distinguishing features of ocular artifacts is crucial for accurate EEG
interpretation and the differentiation of these artifacts from pathological
brain activity or other types of artifacts in EEG recordings.
Comments
Post a Comment