Presented at the Neonatal Society 2015 Autumn Meeting.
Lee CW1,2, Cooper RJ1,3, Dempsey LA1,3, Chalia M1,2, Brigadoi S1,3, Everdell N1,3, Hebden JC1,3, Austin T1,2
1 neoLAB, The Evelyn Perinatal Imaging Centre, Cambridge University Hospitals NHS Foundation Trust, UK
2 Department of Neonatology, Cambridge University Hospitals NHS Foundation Trust, UK
3 Department of Medical Physics and Biomedical Engineering, University College London, UK
Background: In preterm brain injury, subtle changes of dysmaturation may be missed with conventional brain imaging. Diffuse Optical Imaging (DOI) is a portable, non-invasive method that uses near-infrared light to produce images of cerebral haemodynamic activity. In this feasibility study, DOI was used to measure spontaneous brain activity, known as resting state functional connectivity (RSFC), in infants as a potential biomarker of brain development.
Methods: Written consent was obtained from parents for infants to participate in this study. 30 healthy term infants (median gestation at birth: 40 weeks) were recruited for DOI scans within the first week of life (mean: 2 days). Infants were scanned using the UCL Optical Topography system and a soft, flexible head cap (EasyCap, Germany) containing a dense array of DOI sensors. Infants were asleep for up to 1 hour during scanning in the Evelyn Perinatal Imaging Centre, Rosie Hospital, Cambridge.
Results: 9 infants were excluded from further analysis due to extensive motion artifact in the data. 4-dimensional DOI images of oxyhaemoglobin concentration changes were reconstructed using a neonatal gestational age-appropriate head atlas and a multispectral approach with the UCL TOAST forward modelling and image reconstruction package (1). Functionally connected brain regions demonstrating correlating slow oscillations of oxyhaemoglobin in the RSFC frequency range (0.009-0.08Hz) were identified using a seed-based approach and independent component analysis. The results revealed RSFC image maps resembling bilateral RSFC networks between homotopic temporal and sensorimotor regions.
Conclusion: Our results agree with previous studies that observed RSFC networks in the newborn (2,3). Our next step is to combine this modality with EEG and a neurobehavioural assessment to investigate early development of brain function in prematurity.
Corresponding author: cwl36@cam.ac.uk
References
1. Arridge et al. Med Phys 20(2 Pt1), 299-309
2. Fransson et al., PNAS 2007, 104(39), 15531-6
3. Smyser et al., Cerebral Cortex 2010, 20, 2852-62
4. Ferradal et al., Cerebral Cortex 2015, doi: 10.1093/cercor/bhu320