Representative slices of whole-brain DTI colour maps of the thalamus (Th) for mean diffusivity (MD).

<p>Voxel diffusivity intensities falling below the low threshold are shown in red for MD measurements for all lamb brains. All low-diffusion maps are overlaid on diffusion images for a slice passing through the Th. All lambs in the unoperated control (Cont n = 6; A) group had no low MD values in the Th, but low MD values appeared in the Th of about lambs following sham surgery (Sham n = 5; B), lambs following injurious ventilation (INJ n = 5; C), and lambs following umbilical cord occlusion (INJ+UCO n = 7; D).</p

Fetal characteristics at the time of intervention at 124 days of gestation.

<p>Fetal characteristics at the time of intervention at 124 days of gestation.</p

Representative slices of whole-brain DTI colour maps of the thalamus (Th) for radial diffusivity (RD).

<p>Voxel diffusivity intensities falling below the low threshold are shown in red for RD measurements for all lamb brains. All low-diffusion maps are overlaid on diffusion images for a slice passing through the Th. All lambs in the unoperated control (Cont n = 6; A) group had no low RD values in the Th, but low RD values appeared in the Th of 4 lambs following sham surgery (Sham n = 5; B), 4 lambs following injurious ventilation (INJ n = 5; C), and 6 lambs following umbilical cord occlusion (INJ+UCO n = 7; D).</p

Absolute magnetic resonance spectroscopy (MRS) concentrations of metabolites in the preterm lamb brain.

<p>Individual absolute concentrations of lactate (Lac), creatine (Cr), choline (Cho), and N-acetylaspartate (NAA) using a single-voxel MRS encompassing supratentorial central white matter and deep grey matter in the unoperated control (Cont; blue open squares n = 6), sham surgery (Sham; blue closed squares n = 5), injurious ventilation (INJ; red open circles n = 5), and INJ + umbilical cord occlusion (INJ+UCO; red closed circles n = 7) groups. One way ANOVA comparisons tests relative to the Cont group were used with <i>P</i><0.05 was considered statistically significant. *<i>P</i><0.01, **<i>P</i><0.001 vs INJ+UCO.</p

Representative slices of whole-brain DTI colour maps of the thalamus (Th) for axial diffusivity (AD).

<p>Voxel diffusivity intensities falling below the low threshold are shown as red for AD measurements for all lamb brains. All low-diffusion maps are overlaid on diffusion images for a slice passing through the thalamus (Th). In the injurious ventilation (INJ n = 5; C) and umbilical cord occlusion (INJ+UCO n = 7; D) groups, red indicates lower values in the range of the threshold, while black indicates values below the threshold (see explanation in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0188737#pone.0188737.s002" target="_blank">S2 Fig</a>). One sham surgery (Sham n = 5; B), one INJ, and three INJ+UCO lambs had widespread lower diffusivity values in the Th than unoperated control lambs (Cont n = 6; A).</p

Comparison of voxel-based colour-map images for the whole brain.

<p>Images were compared for axial diffusivity (AD), radial diffusivity (RD), and mean diffusivity (MD) values below the threshold for specified regions in the lamb brain in all groups. The white matter (WM) regions were located in the thalamus (Th), internal capsule (IC), periventricular WM (PVWM), frontal WM (FWM), and cerebellum (CB) vermis. There were widespread lower AD, RD, and MD intensities in all WM regions in the umbilical cord occlusion (INJ+UCO n = 7; red closed circles) and injurious ventilation (INJ n = 5; red open circles) groups, but this did not reach statistical significance. While there were few lower diffusivities in WM regions in the sham surgery (Sham n = 5; blue closed squares) group the unoperated control (Cont n = 6; blue open squares) lambs showed very few voxels of low AD, RD, and MD intensities.</p

Physiological parameters.

<p>(A) Fraction of inspired oxygen (FiO₂) in the unoperated control (Cont; blue open squares n = 6), sham surgery (Sham; blue closed squares n = 5), injurious ventilation (INJ; red open circles n = 5), and INJ + umbilical cord occlusion (INJ+UCO; red closed circles n = 7) groups. (B) pH. (C) Partial pressure of arterial oxygen (PaO₂) and (D) carbon dioxide (PaCO₂). *<i>P</i><0.01, **<i>P</i><0.001 vs INJ+UCO.</p

Percentage of lambs found to have AD, RD, and MD in the selected WM regions of each group below the colour map threshold intensity 90% confidence interval of the Cont group.

<p>Percentage of lambs found to have AD, RD, and MD in the selected WM regions of each group below the colour map threshold intensity 90% confidence interval of the Cont group.</p