Chemical shift imaging and localised magnetic resonance spectroscopy in full-term asphyxiated neonates.

BACKGROUND

Diagnosis of brain lesions after birth anoxia-ischemia is essential for appropriate management. Clinical evaluation is not sufficient. MRI has been proven to provide useful information.

OBJECTIVE

To compare abnormalities observed with MRI, including diffusion-weighted imaging (DWI), localised magnetic resonance spectroscopy (MRS) and chemical shift imaging (CSI) and correlate these findings with the clinical outcome.

MATERIALS AND METHODS

Fourteen full-term neonates with birth asphyxia were studied. MRI, MRS and CSI were performed within the first 4 days of life.

RESULTS

Lesions observed with DWI were correlated with outcome, but the apparent diffusion coefficient (ADC) did improve diagnostic confidence. The mean value of Lac/Cr for the neonates with a favourable outcome was statically lower than for those who died (0.22 vs 1.04; P = 0.01). The same results were observed for the Lac/NAA ratio (0.21 vs 1.23; P = 0.01). Data obtained with localised MRS and CSI were correlated for the ratio N-acetyl-aspartate/choline, but not for the other metabolites. No correlation was found between the ADC values and the metabolite ratios.

CONCLUSIONS

Combination of these techniques could be helpful in our understanding of the physiopathological events occurring in neonates with asphyxia.