Structures Showing Negative Correlations of Signal Intensity with Postnatal Age on T1-weighted Imaging of the Brain of Newborns and Infants. T1強調像での信号強度が出生後日数と負の相関性を示す新生児・乳児期の脳構造

Purpose: Although the neonatal and infantile brain typically shows sequential T1 shortening according to gestational age as a result of myelination, several structures do not follow this rule. We evaluated the relationship between the signal intensity of various structures in the neonatal and infantile brain on T1-weighted imaging (T1WI) and either postnatal or gestational age. Materials and Methods: We examined magnetic resonance images from 120 newborns and infants without any abnormalities in the central nervous system. Written informed consent was obtained from all parents and the institutional review board approved the study. Gestational age at examination ranged from 35 weeks, 3 days to 46 weeks, 6 days, and postnatal age ranged from 7 days to 127 days. Signal intensity on T1WI was evaluated on a scale from Grade 1 (indistinguishable from surrounding structures) to Grade 4 (higher than cortex and close to fat). We evaluated relationships between the T1 signal grades of various structures in the neonatal brain and postnatal or gestational age using Spearman’s correlation analysis. Results: Significant positive correlations were identified between T1 signal grade and gestational age in the pyramidal tract (P < 0.001). Conversely, significant negative correlations were evident between T1 signal grade and postnatal age (P < 0.001), in structures including the stria medullaris thalami, fornix cerebellar vermis, dentate nucleus and anterior pituitary gland. Conclusion: Significant negative correlations exist between signal intensity on T1WI and postnatal age in some structures of the neonatal and infantile brain. Some mechanisms other than myelination might play roles in the course of signal appearance.

博士（医学）・乙第1405号・平成29年6月28日

Copyright © 2017 by Japanese Society for Magnetic Resonance in Medicine : This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivativesInternational License(https://creativecommons.org/licenses/by-nc-nd/4.0/deed.ja).

identifier:Magnetic resonance in medical sciences Vol.16 No.4 p.325-331 (2017)

identifier:13473182

identifier:http://ginmu.naramed-u.ac.jp/dspace/handle/10564/3351

identifier:Magnetic resonance in medical sciences, 16(4): 325-331

開始ページ : 325

終了ページ : 331

Copyright © 2017 by Japanese Society for Magnetic Resonance in Medicine : This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives International License(https://creativecommons.org/licenses/by-nc-nd/4.0/deed.ja).