Related Experiment Video
Updated: Sep 29, 2025
Transcutaneous Microcirculatory Imaging in Preterm Neonates
Published on: December 31, 2015
Different from the Beginning: WM Maturity of Female and Male Extremely Preterm Neonates-A Quantitative MRI Study
V U Schmidbauer1, M S Yildirim1, G O Dovjak1
1From the Department of Biomedical Imaging and Image-guided Therapy (V.U.S., M.S.Y., G.O.D., M.W., F.P., M.S., F.L., F.S., C.L., D.P., G.K.).
Insights
Male preterm infants show more immature brain development in specific regions compared to females. These sex differences in white matter maturation highlight the need for personalized neonatal brain imaging approaches.
Area of Science:
- Neuroscience
- Radiology
- Developmental Biology
Background:
- Former preterm males face higher neurodevelopmental disability risks than females born at the same gestational age.
- Investigating sex-based variations in early brain region maturity is crucial for understanding developmental trajectories.
Purpose of the Study:
- To examine sex-related differences in the maturity of early myelinating brain regions in extremely preterm infants.
- To utilize advanced Magnetic Resonance (MR) imaging techniques for quantitative analysis.
Main Methods:
- Retrospective analysis of 35 extremely preterm neonates (born <28 weeks gestational age) using diffusion tensor and relaxometry-based MR imaging at term-equivalent age.
- Quantitative MR imaging metrics including fractional anisotropy, apparent diffusion coefficient (ADC), and T1/T2 relaxation times were measured in the brainstem and internal capsule.
- Statistical analyses (ANCOVA, paired t-test) were performed to compare sexes and detect hemispheric asymmetries.
Main Results:
- Significant sex differences in T2-relaxation time of the pontine tegmentum and midbrain, and T1-relaxation time of the midbrain and left internal capsule were observed.
- Male neonates exhibited more immature brainstem and left internal capsule white matter compared to females at term-equivalent age.
- Both sexes showed significant interhemispheric differences in fractional anisotropy and ADC within the posterior limbs of the internal capsule.
Conclusions:
- Quantitative MR imaging reveals significant sex-related and interhemispheric differences in white matter maturation in preterm infants.
- Male preterm infants demonstrate delayed maturation in the brainstem and left internal capsule compared to female counterparts.
- Addressing sex differences in white matter maturation is essential for developing personalized neonatal brain imaging and care strategies.
Background And Purpose:
Former preterm born males are at higher risk for neurodevelopmental disabilities compared with female infants born at the same gestational age. This retrospective study investigated sex-related differences in the maturity of early myelinating brain regions in infants born <28 weeks' gestational age using diffusion tensor- and relaxometry-based MR imaging.
Materials And Methods:
Quantitative MR imaging sequence acquisitions were analyzed in a sample of 35 extremely preterm neonates imaged at term-equivalent ages. Quantitative MR imaging metrics (fractional anisotropy; ADC [10-3mm2/s]; and T1-/T2-relaxation times [ms]) of the medulla oblongata, pontine tegmentum, midbrain, and the right/left posterior limbs of the internal capsule were determined on diffusion tensor- and multidynamic, multiecho sequence-based imaging data. ANCOVA and a paired t test were used to compare female and male infants and to detect hemispheric developmental asymmetries.
Results:
Seventeen female (mean gestational age at birth: 26 + 0 [SD, 1 + 4] weeks+days) and 18 male (mean gestational age at birth: 26 + 1 [SD, 1 + 3] weeks+days) infants were enrolled in this study. Significant differences were observed in the T2-relaxation time (P = .014) of the pontine tegmentum, T1-relaxation time (P = .011)/T2-relaxation time (P = .024) of the midbrain, and T1-relaxation time (P = .032) of the left posterior limb of the internal capsule. In both sexes, fractional anisotropy (P [♀] < .001/P [♂] < .001) and ADC (P [♀] = .017/P [♂] = .028) differed significantly between the right and left posterior limbs of the internal capsule.
Conclusions:
The combined use of various quantitative MR imaging metrics detects sex-related and interhemispheric differences of WM maturity. The brainstem and the left posterior limb of the internal capsule of male preterm neonates are more immature compared with those of female infants at term-equivalent ages. Sex differences in WM maturation need further attention for the personalization of neonatal brain imaging.
