Neurostimulation EEG artifacts: VNS, RNS, and DBSAccurately recognizing artifacts on electroencephalogram (EEG) is necessary to prevent EEG misinterpretation and epilepsy misdiagnosis. EEG artifacts generated by neurostimulation devices (Figures 1 and 2) can be identified based on their unique spatial and frequency properties1.
Figure 1.
Vagus nerve stimulation (VNS) EEG artifact. Scalp EEG: sensitivity 7 µV/mm, LF 1 Hz, HF 70 Hz, notch on; invasive EEG: sensitivity 100 µV, LF 0.53 Hz, HF 600 Hz, notch off.
Vagus nerve stimulation (VNS) EEG artifact. Scalp EEG: sensitivity 7 µV/mm, LF 1 Hz, HF 70 Hz, notch on; invasive EEG: sensitivity 100 µV, LF 0.53 Hz, HF 600 Hz, notch off.
Figure 2.
Responsive neurostimulation (RNS) and deep brain stimulation (DBS) scalp EEG artifacts - extended longitudinal bipolar montages (with additional frontotemporal electrodes). EEG: sensitivity 7 µV/mm, LF 1 Hz, HF 70 Hz, notch on.
Responsive neurostimulation (RNS) and deep brain stimulation (DBS) scalp EEG artifacts - extended longitudinal bipolar montages (with additional frontotemporal electrodes). EEG: sensitivity 7 µV/mm, LF 1 Hz, HF 70 Hz, notch on.
VNS and RNS artifacts display an electrical interference-like “spiky” morphology with a distribution that is incompatible with a cerebral source and frequencies that mirror stimulation settings. DBS artifact features diffuse electrical interference with a relatively monomorphic appearance, and its frequency can vary depending on intermittent versus continuous neurostimulation - indicated for epilepsy and movement disorders, respectively.
REFERENCES
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1. McKay JH, Tatum WO. Artifact mimicking ictal epileptiform activity in EEG. J Clin Neurophysiol. 2019 Jul;36(4):275-88. https://doi.org/10.1097/wnp.0000000000000597
» https://doi.org/10.1097/wnp.0000000000000597
Publication Dates
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Publication in this collection
11 June 2021 -
Date of issue
Aug 2021
History
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Received
23 Aug 2020 -
Reviewed
24 Oct 2020 -
Accepted
28 Oct 2020
Scalp EEG (top), extended longitudinal bipolar montage (with additional frontotemporal electrodes) showing a burst of low-voltage sharply contoured artifact mostly at the EKG channel but also at the across FT9-FT10 and A1-A2 bipolar channels. Invasive EEG (bottom), bipolar montage showing a burst of low-voltage 20 Hz sharply contoured artifact at the EKG channel. The artifacts’ 20 Hz frequency corresponded to the stimulating frequency in both cases.
RNS (top, 15-second; middle, 5-second view): repetitive 200 Hz stimulation artifact (red rectangles) followed by C3-P3 device detection artifact (blue stars). RNS strip electrodes were in the left posterior temporal topography with generator in the left frontal region. DBS (bottom): continuous, diffuse, electrical interference without evolution.