Data from: Three-dimensional infrared scanning: An enhanced approach for spatial registration of probes for neuroimaging

Significance: Accurate spatial registration of probes (e.g., optodes and
electrodes) for measurement of brain activity is a crucial aspect in many
neuroimaging modalities. It may increase measurement precision and enable
the transition from channel-based calculations to volumetric
representations. Aim: This technical note evaluates the efficacy of a
commercially available infrared three-dimensional (3D) scanner under
actual experimental (or clinical) conditions and provides guidelines for
its use. Method: We registered probe positions using an infrared 3D
scanner and validated them against magnetic resonance imaging (MRI) scans
on five volunteer participants. Results: Our analysis showed that with
standard cap fixation, the average Euclidean distance of probe position
among subjects could reach up to 43 mm, with an average distance of 15.25
mm [standard deviation (SD) = 8.0]. By contrast, the average distance
between the infrared 3D scanner and the MRI-acquired positions was 5.69 mm
(SD = 1.73), while the average difference between consecutive infrared 3D
scans was 3.43 mm (SD = 1.62). The inter-optode distance, which was fixed
at 30 mm, was measured as 29.28 mm (SD = 1.12) on the MRI and 29.43 mm (SD
= 1.96) on infrared 3D scans. Our results demonstrate the high accuracy
and reproducibility of the proposed spatial registration method, making it
suitable for both functional near-infrared spectroscopy and
electroencephalogram studies. Conclusions: The 3D infrared scanning
technique for spatial registration of probes provides economic efficiency,
simplicity, practicality, repeatability, and high accuracy, with potential
benefits for a range of neuroimaging applications. We provide practical
guidance on anonymization, labeling, and post-processing of acquired
scans.