Magnetic Resonance Imaging and Spectroscopy Biomarkers of Neonatal Hypoxic Ischemic Encephalopathy

Magnetic Resonance Imaging (MRI) and Spectroscopy (MRS) Biomarkers of Neonatal Hypoxic Ischemic Encephalopathy

Neonatal hypoxic ischemic encephalopathy (HIE) is a serious neurological condition characterised by acute or subacute brain injury arising from perinatal hypoxia. HIE is thought to affect approximately 0.2% of live births, and is associated with a high risk of mortality or long-term neurological disability.

Accurate biomarkers for long-term neuro-developmental outcome following HIE are extremely important both for clinical management and the evaluation of therapeutic approaches. According to a recent meta-analysis, the ratio of the cerebral concentrations of lactate and N-acetyl aspartate (NAA), two neuro-metabolites detectable with magnetic resonance spectroscopy (MRS), currently represents the most accurate prognostic indicator of outcome following HIE. However, for various technical reasons standard MRS methods do not offer optimal sensitivity for detecting lactate, which may potentially be improved with a custom lactate editing MRS sequence. In addition, while perfusion has also been suggested as a potential biomarker for neuro-developmental outcome following HIE, due to a paucity of MR perfusion imaging studies in neonates, the prognostic accuracy of perfusion MR measures has not been evaluated in comparison with more established MR biomarkers. The aims of this study are:

1. to evaluate the relative sensitivity of a custom lactate editing MRS pulse sequence (specialist software) relative to the standard point resolved (PRESS) MRS sequence for detecting lactate in neonates with suspected HIE.
2. to evaluate the sensitivity and specificity of MR perfusion measures in comparison to MRS measures as predictors of neuro-developmental outcome at 2 years.

Inclusion Criteria:

• Newborn infants (born at >36 weeks) with suspected perinatal asphyxia. Written informed consent from both parents.

Exclusion Criteria:

• Prematurity (born at < 36 weeks). Lack of written informed consent from both parents.