Abstract
<b><i>Introduction:</i></b> The SafeBoosC-III trial investigated the effect of cerebral oximetry-guided treatment in the first 72 h after birth on mortality and severe brain injury diagnosed by cranial ultrasound in extremely preterm infants (EPIs). This ancillary study evaluated the effect of cerebral oximetry on global brain injury as assessed by magnetic resonance imaging (MRI) at term equivalent age (TEA). <b><i>Methods:</i></b> MRI scans were obtained between 36 and 44.9 weeks PMA. The Kidokoro score was independently evaluated by two blinded assessors. The intervention effect was assessed using the nonparametric Wilcoxon rank sum test for median difference and 95% Hodges-Lehmann (HL) confidence intervals (CIs). The intraclass correlation coefficient (ICC) was used to assess the agreement between the assessors. <b><i>Results:</i></b> A total of 210 patients from 8 centers were included, of whom 121 underwent MRI at TEA (75.6% of alive patients): 57 in the cerebral oximetry group and 64 in the usual care group. There was an excellent correlation between the assessors for the Kidokoro score (ICC agreement: 0.93, 95% CI: 0.91–0.95). The results showed no significant differences between the cerebral oximetry group (median 2, interquartile range [IQR]: 1–4) and the usual care group (median 3, IQR: 1–4; median difference −1 to 0, 95% HLCI: −1 to 0; <i>p</i> value 0.1196). <b><i>Conclusions:</i></b> In EPI, the use of cerebral oximetry-guided treatment did not lead to significant alterations in brain injury, as determined by MRI at TEA. The strong correlation between the assessors highlights the potential of the Kidokoro score in multicenter trials.