Quantitative analysis of MR images in asphyxiated neonates: Correlation with neurodevelopmental outcome

BACKGROUND AND PURPOSE: MR imaging has been shown to be of prognostic signi ficance in the evaluation of asphyxiated neonates. The purpose of this proj ect tvas to determine whether the use of intensity ratios in key regions of the brain might better detect regions of injured brain and thus improve th e correlation of imaging findings with 12-month neurodevelopmental outcome. METHODS: Prospectively acquired MR studies of 53 asphyxiated neonates were reviewed retrospectively. Signal intensities from standard T1- and T2-weigh ted images of seven major brain regions that are affected in asphyxia were measured. Intensity ratios were calculated by dividing the signal intensity of each brain region by the signal intensity of the ocular vitreous. The i ntensity ratios mere then correlated with 12-month neurodevelopmental outco me. These results were compared with correlations determined by a qualitati ve scoring system. RESULTS: The only significant statistical correlation between the intensity ratios and 12-month neurodevelopmental outcome were those of anterior wate rshed injury with the Mental Development Index of the Bayley Scales of Infa nt Development II. The qualitative measurements showed a strong correlation with many outcome parameters. CONCLUSION: Standard qualitative assessment is more predictive of neurodeve lopmental outcome than is quantitative analysis. This finding most likely r eflects the inability of the quantitative assessment of intensity ratios to compensate for the day-to-day evolution of signal intensity of the injured neonatal brain. Anterior watershed injury may be predictive of abnormal co gnitive outcome; examination of these patients at age 30 months will be imp ortant to determine the accuracy of this observation.