Stacy Kellan Goergen MBBS, Presenter: Nothing to Disclose

Jeanie Cheong MBBS,PhD, Abstract Co-Author: Nothing to Disclose

Hazel An MD, Abstract Co-Author: Nothing to Disclose

Flora Wong MBBS, Abstract Co-Author: Nothing to Disclose

Elizabeth Carse MBBS, Abstract Co-Author: Nothing to Disclose

Margaret Charlton BA,MEd, Abstract Co-Author: Nothing to Disclose

Gillian Whiteley MBBS,FRANZC, Abstract Co-Author: Nothing to Disclose

Rachel Evans MBBS,FRANZC, Abstract Co-Author: Nothing to Disclose

Jennifer Clark RN, Abstract Co-Author: Nothing to Disclose

To compare diffusion weighted (DWI) and non DWI MRI,  proton MR spectroscopy (MRS), and clinical biomarkers for prediction of intellectual and motor function at 2 years of age in term infants with  hypoxic ischaemic brain injury.    

20 consecutive infants > or = 36 weeks' gestation with HIE were enrolled between December 2005 and March 2009 . MRI was performed day 3-7 (mean = 5) including DWI and MRS. Baseline data included gender, 5 minute Apgar, Sarnat score, pH (cord blood, arterial, or capillary), and seizures. MRI was scored independently by 3 radiologists, blinded to clinical information and outcome, following development of a detailed image scoring system that was trialled on a training set of 5 other MRI studies in term infants with HIE. Lactate to NAA ratio in the lentiform nucleus was calculated. At 2 years, children were assessed by a pediatric developmental psychologist and pediatrician . A score for each of the three domains of the Bayley Scales III of infant development was recorded. Interobserver agreement of the radiologists about degree of abnormality in each of 10 regions of the brain was measured. Logistic regression was performed to determine which predictor variables were associated with adverse outcome (death, Bayley score for any domain 70 or less).

  Agreement of the 3 readers on DWI score was significantly higher (68%) than for non-DWI score (45%),  chi-square =32 on 5 d.f. (P <0.0001). Univariate analysis showed Lac:NAA was not significantly associated with outcome (OR = 1.12, p=0.72) nor were 5 minute Apgar, pH, Sarnat score, seizures, or gender (p values = 0.47- 0.93). Thalamic DWI score (OR = 167; 2.5-11,294; p=0.017) and posterior limb internal capsule DWI score (OR=33; 1.5-720, p=0.03) and composite score for putamen, thalamus, subthalamic nucleus and posterior limb of internal capsule on DWI (OR: 236; 1.7 - 33,414, p = 0.03) were the best predictors of outcome. No child with good outcome had DWI abnormality in the brainstem.

Agreement on DWI score was signficantly higher than non DWI. Composite DWI score for basal ganglia, thalamus, subthalamic nucleus and posterior limb internal capsule was significantly associated with poor outcome.

Our findings contradict the conclusions of a recent systematic review by Thayli which found that image analysis was not predictive of outcome in infants with HIE but lactate to NAA ratio was.

Goergen, S, Cheong, J, An, H, Wong, F, Carse, E, Charlton, M, Whiteley, G, Evans, R, Clark, J, MRI Biomarkers in Infants with Global Hypoxic Ischaemic Brain Injury: Can We Predict Outcome at 2 Years?.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11005915.html