Abnormal Measures of White Matter Integrity in Newborns with Hypoxic Ischemic Encephalopathy (HIE) (P7.319)

Background and Objective: White matter abnormalities in neonates are strong predictors of motor, cognitive disabilities. Abnormalities on clinical MRI do not always correlate with neurological development. Despite the potential to quantify white matter lesions, Diffusion Tensor Imaging and Fractional Anisotropy (FA ) are not routinely used. Thus, quantification of subtle, but functionally relevant lesions is lacking. The objective of this work is to demonstrate abnormalities of white matter in newborns with HIE using FA in multiple, clinically significant areas. Additionally we investigated the relation between brain lesions and clinical risk factors for HIE. Methods: Subjects: Ten term neonates with HIE, seven age-matched healthy neonates were included. Clinical Data: Risk factor for HIE included: cord pH<7.2, infections, hypertention, drugs. Imaging: DTIsequence was acquired at day of life 4-10. FA maps were calculated in DTI-Studio after correction for motion and eddie current distortion. ROIs were blindly drawn bilaterally on average DWI image in corticospinal tracts (CST), genu, splenium, optic radiation,temporal white matter, periventricular white matter. Inter-rater reliability was determined between two investigators. Results: Intra-class correlations for a random sample of 6 subjects were high (rs >0.90). Comparisons between groups revealed significant differences in genu; right, left periventricular white matter and right, left temporal white matter (Fs > 6.5, ps HIE).2-tailed ANOVA analysis showed correlation between cord pH and FA values of right, left periventricular region and right corticospinal tracts. FA was lower in the HIE group in the remaining ROIs, but did not reach statistical significance. Discussion: We demonstrated differences in FA in multiple brain regions in newborns with HIE when compared to health newborn. Further studies are necessary to determine if FA at this young age correlates with neurologic development. Disclosure: Dr. Pergami has nothing to disclose. Dr. Nanavati has nothing to disclose. Dr. Hou has nothing to disclose. Dr. Yossuck has nothing to disclose. Dr. Smith has nothing to disclose. Dr. Carpenter has nothing to disclose. Dr. Haut has nothing to disclose.