Infants are at risk of developing motor and cognitive neurodevelopmental disabilities as a sequelae to hypoxic-ischemic brain injury during the perinatal period. It is an ongoing challenge to predict the severity and extent of future developmental impairment during the neonatal period. This study will help test the feasibility of conducting a large-scale study that evaluates the role of diffuse optical tomography as a bedside neuroimaging tool in complementing the prognostic value of conventional and diffusion weighted MRI for predicting neurodevelopmental outcome in neonates with perinatal hypoxic-ischemic brain injury.

Perinatal hypoxic-ischemic brain injury is a major cause of childhood disabilities including cerebral palsy, developmental delay, attention deficits, behavioral concerns, and learning disabilities. Accurate prediction of neurologic deficits in the neonatal period is difficult, especially the ability to predict later cognitive impairment and socio-emotional challenges. Many of these disabilities are manifested at school age when the child is beyond the critical time window of early brain development. Prognostic tools that help to identify neonates most at risk of developing neuro-deficits after perinatal asphyxia are needed and would enable targeted early intervention in infancy, when the developing brain is most amenable to positive changes and improve neurologic outcome. Currently, structural changes observed in MRI brain images are used to predict outcome. However, this modality does not provide information on brain function, nor is it a good prognostic marker of future neurocognitive outcome. Functional MRI (fMRI) is time-consuming and not commonly a part of clinical assessment of the neonates. Diffuse Optical Tomography (DOT) using near-infrared light has been applied in research settings to map the functional connections between key brain regions. This technology, although reported to be safe and reliable in small studies, has not been widely used in the neonatal clinical setting. This approach is based on the synchronous, spontaneous fluctuations of cerebral blood flow in different regions of the brain that are functionally, yet not necessarily anatomically connected. DOT combines the portability and cap-based scanning of EEG with spatial resolution high enough to create detailed cortical maps of the neonatal brain. Compared to MRI and fMRI brain imaging, DOT is portable, light weight, has high body motion tolerance, does not produce noise and does not require infant sedation. It has the potential to be a powerful bedside non-invasive clinical neuroimaging tool. Currently, the predictive accuracy of DOT based neonatal brain connectivity measures in prognosticating early childhood is unknown. This study aims to assess the feasibility of the processes that are key to the success of a large-scale prospective study aimed at investigating the prognostic value of bedside DOT derived biomarker in neonatal brain after perinatal hypoxic-ischemic brain injury.

Inclusion Criteria:

• Newborns admitted to the McMaster Children's Hospital Neonatal Intensive Care Unit with the diagnosis of hypoxic-ischemic encephalopathy will be considered for this study
• Gestational age of 35 weeks or greater
• Birth weight more than 1.8 Kg

Exclusion Criteria:

(i) suspected or confirmed congenital malformations, (ii) chromosomal anomalies, (iii) inborn errors of metabolism, (iv) congenital infections, (v) neonatal encephalopathy other than HIE, (vi) baby requires respiratory support in the form of CPAP, Mechanical ventilation, high flow nasal cannula and (vii) scalp injury or non-intact skin surface in the scalp

A cohort of neonates admitted with clinical history suggestive of perinatal hypoxic-ischemic encephalopathy will be enrolled to the study, irrespective of whether they are considered eligible or ineligible for therapeutic hypothermia. The intervention (DOT measurement) will be conducted after therapeutic hypothermia is completed and neonate is considered hemodynamically stable to tolerate the procedure.