Accuracy of high-density EEG electrode position measurement using an optical scanner compared with the photogrammetry...

Area of Science:

• Neuroscience
• Medical Imaging
• Biomedical Engineering

Background:

• High-density electroencephalography (EEG) requires precise electrode localization for accurate source imaging.
• Traditional methods like photogrammetry can be time-consuming and less accurate.
• Accurate 3D electrode coordinate measurement is crucial for presurgical evaluations.

Purpose of the Study:

• To assess the feasibility and accuracy of a handheld optical scanner for measuring 3D EEG electrode coordinates.
• To compare the optical scanner's performance against a validated photogrammetry method.
• To evaluate the clinical applicability of optical scanning for high-density EEG arrays.

Main Methods:

• A handheld optical scanner was used to capture 3D coordinates of 256 EEG electrodes.
• Electrode coordinates were co-registered with patient MRI scans.
• A cohort of 60 patients was divided into two groups: 30 measured with optical scanning and 30 with photogrammetry.

Main Results:

• The optical scanner achieved a significantly lower mean distance error (1.78 mm) compared to photogrammetry (2.43 mm) (p < 0.001).
• Scanning time per patient ranged from 5-10 minutes.
• The optical scanner demonstrated higher accuracy and feasibility.

Conclusions:

• Handheld optical scanning offers superior accuracy and feasibility for measuring 3D EEG electrode positions compared to photogrammetry.
• This technology is suitable for clinical implementation in EEG source imaging, particularly for presurgical evaluations.