Kim Annink

13 General introduction Figure 2: Patterns of brain injury in infants with HIE. A. shows an example of an apparent diffusion coefficient (ADC) map with severe diffusion restriction of the thalami (deep grey matter type injury), B. shows an example of an ADC map with severe restriction of the white matter (watershed type injury), C. shows an example of near total injury. Diffusion restriction results in a low signal intensity on the ADC map. Neuroimaging The different patterns of brain injury can be visualized using neuroimaging techniques. Neuroimaging in infants with HIE provides information about the extent and pattern of brain injury and as such is helpful to predict neurodevelopmental outcomes. Predicting neurodevelopmental outcome as early as possible is essential for clinical decision making and counselling of parents. Early biomarkers for neurodevelopmental outcome can also be used as outcome measures in randomized controlled trials (RCT). Shankaran et al. showed, in one of the large therapeutic hypothermia trials, that neonatal MRI can be used as a biomarker for six to seven year outcome (18). Neuroimaging is not the only biomarker available for the prediction of neurodevelopmental outcome. In clinical practice, a combination of neuroimaging, neurophysiology and clinical condition (i.e. neurological examination and multi-organ failure) is used to predict neurodevelopmental outcome. The combination of multiple techniques have shown to increase sensitivity and specificity to predict neurodevelopmental outcome. To illustrate, Leijser et al. showed that an abnormal amplitude-integrated electroencephalography (aEEG) background pattern (sensitivity 0.93, specificity 0.75) or severely abnormal Magnetic Resonance Imaging (MRI) (sensitivity 0.74, specificity 1.00) had both high predictive values for adverse outcome at two years of age in infants with HIE, but the combination of aEEG and MRI even further increased sensitivity and specificity (19). Although, this thesis 1