Background and aim Biomarkers are needed to test novel neuroprotective therapies efficiently. The aim was to test the hypothesis that fractional anisotropy (FA) in white matter (WM) and mean diffusivity (MD) in grey matter (GM) correlate to subsequent developmental quotient (DQ) in infants with hypoxic-ischaemic encephalopathy (HIE).
Methods We studied 40 infants with HIE (median [range] age 39+5 [36+4–42+3]), who underwent MRI within 21 days of birth and neurodevelopmental assessment at ≥12 months. Infants with a DQ >2SDs below the mean were considered to have an unfavourable outcome. Cortical, thalamic and WM tissue labels were generated by neonatal atlas-based automated segmentation of the T2-weighted images . Tissue labels were propagated onto the diffusion maps. FA and MD values were determined. Linear regression was performed to assess the correlation between FA/MD and DQ. Estimation of unfavourable outcome with FA/MD in WM and GM was examined using receiver operating characteristic (ROC) analysis.
Results Following correction for multiple comparisons and age at scan significant correlation was found between DQ and FA in WM (p = 0.0002), and MD in thalami (p = 0.0002) and cortex (p = 0.005). ROC analysis to estimate unfavourable outcome showed larger area under the curve (AUC) for FA in WM, than MD in GM (Figure and Table).
Conclusion These data show that FA in WM and MD in GM may be used as biomarkers of outcome following HIE.