Brain growth in the NICU: critical periods of tissue-specific expansion

• Published in: Pediatric research 2018-05, Vol.83 (5), p.976-981
• Main Authors: Matthews, Lillian G, Walsh, Brian H, Knutsen, Clare, Neil, Jeffrey J, Smyser, Christopher D, Rogers, Cynthia E, Inder, Terrie E
• Format: Article
• Language: English
• Subjects: Birth Weight; Brain; Brain - diagnostic imaging; Brain - growth & development; Brain Mapping; clinical-investigation; Female; Gestational Age; Gray Matter - diagnostic imaging; Gray Matter - growth & development; Health risk assessment; Humans; Image Processing, Computer-Assisted; Infant, Newborn; Infant, Premature; Intensive care; Intensive Care Units, Neonatal; Longitudinal Studies; Magnetic Resonance Imaging; Male; Medicine; Medicine & Public Health; Neonatal care; Newborn babies; NMR; Nuclear magnetic resonance; Organ Size; Patient Discharge; Pediatric Surgery; Pediatrics; Pregnancy; Pregnancy Trimester, Third; Prospective Studies; Volumetric analysis; White Matter - diagnostic imaging; White Matter - growth & development
• ISSN: 0031-3998; 1530-0447
• DOI: 10.1038/pr.2018.4

Objective To examine, using serial magnetic resonance imaging (MRI), total and tissue-specific brain growth in very-preterm (VPT) infants during the period that coincides with the early and late stages of the third trimester. Methods Structural MRI scans were collected from two prospective cohorts of VPT infants (≤30 weeks of gestation). A total of 51 MRI scans from 18 VPT subjects were available for volumetric analysis. Brain tissue was classified into cerebrospinal fluid, cortical gray matter, myelinated and unmyelinated white matter, deep nuclear gray matter, and cerebellum. Nine infants had sufficient serial scans to allow comparison of tissue growth during the periods corresponding to the early and late stages of the third trimester. Results Tissue-specific differences in ex utero brain growth trajectories were observed in the period corresponding to the third trimester. Most notably, there was a marked increase in cortical gray matter expansion from 34 to 40 weeks of postmenstrual age, emphasizing this critical period of brain development. Conclusion Utilizing serial MRI to document early brain development in VPT infants, this study documents regional differences in brain growth trajectories ex utero during the period corresponding to the first and second half of the third trimester, providing novel insight into the maturational vulnerability of the rapidly expanding cortical gray matter in the NICU.