Early Assessment of Brain Maturation by MR Imaging Segmentation in Neonates and Premature Infants

Abstract

PURPOSE: We evaluated the impact of premature extrauterine life on brain maturation.

PATIENTS AND METHODS: Twelve neonates underwent MR imaging at 40 (39.64 ± 0.98) weeks (full term). Fifteen premature infants underwent 2 MR imaging examinations, after birth (preterm at birth) and at 40 weeks (41.03 ± 1.33) (preterm at term). A 3D MR imaging technique was used to measure brain volumes compared with intracranial volume: total brain volume, cortical gray matter, myelinated white matter, unmyelinated white matter, basal ganglia (BG), and CSF.

RESULTS: The average absolute volume of intracranial volume (269.8 mL ± 36.5), total brain volume (246.5 ± 32.3), cortical gray matter (85.53 mL ± 22.23), unmyelinated white matter (142.4 mL ±14.98), and myelinated white matter (6.099 mL ±1.82) for preterm at birth was significantly lower compared with that for the preterm at term: the average global volume of intracranial volume (431.7 ± 69.98), total brain volume (391 ± 66,1), cortical gray matter (179 mL ± 41.54), unmyelinated white matter (185.3 mL ± 30.8), and myelinated white matter (10.66 mL ± 3.05). It was also lower compared with that of full-term infants: intracranial volume (427.4 mL ± 53.84), total brain volume (394 ± 49.22), cortical gray matter (181.4 ± 29.27), unmyelinated white matter (183.4 ± 27.37), and myelinated white matter (10.72 ± 4.63). The relative volume of cortical gray matter (30.62 ± 5.13) and of unmyelinated white matter (53.15 ± 4.8) for preterm at birth was significantly different compared with the relative volume of cortical gray matter (41.05 ± 5.44) and of unmyelinated white matter (43.22 ± 5.11) for the preterm at term. Premature infants had similar brain tissue volumes at 40 weeks to full-term infants.

CONCLUSION: MR segmentation techniques demonstrate that cortical neonatal maturation in moderately premature infants at term and term-born infants was similar.