In vivo quantitative ultrasonic evaluation of neonatal brain with a real time integrated backscatter imaging system.

We applied the integrated backscatter (IBS) imaging system to the evaluation of the normal neonatal brain of different birth-weights: extremely low-birth-weight (N=13), very-low-birth-weight (N=14), low-birth weight (N=14), and normal birth weight (N=19). The IBS values in six regions of interest, the deep white matter, subcortical white matter, choroid plexus, thalamus, lateral ventricle, and occipital bone, were compared among groups of different birth weights, gestational age, and postnatal age: at the date of birth and 28 approximately 30 days after birth. The IBS values were higher in the order of bone>choroid plexus>deep white matter>subcortical white matter>thalamus>lateral ventricle and were significantly different except for the lateral ventricle in all the groups at days 0 and 28 approximately 30. The IBS values increased with the decrease of birth weight and gestational age. There was a decrease of IBS values at day 28 compared to that of day 0 in the extremely low birth weight and very low birth weight groups; however, they remained the same in infants with low birth weights and in the normal birth weight group. Further studies to evaluate the significance of this technique for the objective diagnosis of brain insults in neonates are necessary.