Abstract
Significance Diffuse optical tomography (DOT) uses near-infrared light spectroscopy (NIRS) to measure changes in cerebral hemoglobin concentration. Anatomical interpretations of NIRS data requires accurate descriptions of the cranio-cerebral relations and DOT sensitivity to the underlying cortical structures. Such information is limited for pediatric populations because they undergo rapid head and brain development.
Aim The present study aimed to investigate age-related differences in scalp-to-cortex distance and mapping between scalp locations and cortical regions of interest (ROIs) among infants (2 weeks to 24 months with narrow age bins), children (4 and 12 years) and adults (20 to 24 years).
Approach We used spatial scalp projection and photon propagation simulation methods with age-matched realistic head models based on MRIs.
Results There were age-group differences in the scalp-to-cortex distances in infancy. The developmental increase was magnified in children and adults. There were systematic age-related differences in the probabilistic mappings between scalp locations and cortical ROIs.
Conclusions Our findings have important implications in the design of sensor placement and making anatomical interpretations in NIRS and fNIRS research. Age-appropriate realistic head models should be used to provide anatomical guidance for standalone DOT data in infants.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
The manuscript is updated to focus on findings relating to scalp-to-cortex distances and the mapping between scalp locations and cortical regions of interests across age groups. We added emphasis on the implications of the findings.