ObjectivesThe software “SyMRI” generates different MR contrasts and characterizes tissue properties based on a single acquisition of a multi-dynamic multi-echo (MDME)-FLAIR sequence. The aim of this study was to assess the applicability of “SyMRI” in the assessment of myelination in preterm and term-born neonates. Furthermore, “SyMRI” was compared with conventional MRI.MethodsA total of 30 preterm and term-born neonates were examined at term-equivalent age using a standardized MRI protocol. MDME sequence (acquisition time, 5 min, 24 s)–based post-processing was performed using “SyMRI”. Myelination was assessed by scoring seven brain regions on quantitative T1-/T2-maps, generated by “SyMRI” and on standard T1-/T2-weighted images, acquired separately. Analysis of covariance (ANCOVA) (covariate, gestational age (GA) at MRI (GAMRI)) was used for group comparison.ResultsIn 25/30 patients (83.3%) (18 preterm and seven term-born neonates), “SyMRI” acquisitions were successfully performed. “SyMRI”-based myelination scores were significantly lower in preterm compared with term-born neonates (ANCOVA: T1: F(1, 22) = 7.420, p = 0.012; T2: F(1, 22) = 5.658, p = 0.026). “SyMRI”-based myelination scores positively correlated with GAMRI (T1: r = 0.662, n = 25, p ≤ 0.001; T2: r = 0.676, n = 25, p ≤ 0.001). The myelination scores based on standard MRI did not correlate with the GAMRI. No significant differences between preterm and term-born neonates were detectable.Conclusions“SyMRI” is a highly promising MR technique for neonatal brain imaging. “SyMRI” is superior to conventional MR sequences in the visual detection of delayed myelination in preterm neonates.Key Points• By providing multiple MR contrasts, “SyMRI” is a time-saving method in neonatal brain imaging.• Differences concerning the myelination in term-born and preterm infants are visually detectable on T1-/T2-weighted maps generated by “SyMRI”.• “SyMRI” allows a faster and more sensitive assessment of myelination compared with standard MR sequences.Electronic supplementary materialThe online version of this article (10.1007/s00330-019-06325-2) contains supplementary material, which is available to authorized users.

BACKGROUND AND PURPOSE: Preterm birth interferes with regular brain development. The aim of this study was to investigate the impact of prematurity on the physical tissue properties of the neonatal brain stem using a quantitative MR imaging approach. MATERIALS AND METHODS:A total of 55 neonates (extremely preterm [n ¼ 30]: ,28 1 0 weeks gestational age; preterm [n ¼ 10]: 28 1 0-36 1 6 weeks gestational age; term [n ¼ 15]: $37 1 0 weeks gestational age) were included in this retrospective study. In most cases, imaging was performed at approximately term-equivalent age using a standard MR protocol. MR data postprocessing software SyMRI was used to perform multidynamic multiecho sequence (acquisition time: 5 minutes, 24 seconds)-based MR postprocessing to determine T1 relaxation time, T2 relaxation time, and proton density. Mixed-model ANCOVA (covariate: gestational age at MR imaging) and the post hoc Bonferroni test were used to compare the groups.RESULTS: There were significant differences between premature and term infants for T1 relaxation time (midbrain: P , .001; pons: P , .001; basis pontis: P ¼ .005; tegmentum pontis: P , .001; medulla oblongata: P , .001), T2 relaxation time (midbrain: P , .001; tegmentum pontis: P , .001), and proton density (tegmentum pontis: P ¼ .004). The post hoc Bonferroni test revealed that T1 relaxation time/T2 relaxation time in the midbrain differed significantly between extremely preterm and preterm (T1 relaxation time: P , .001/ T2 relaxation time: P ¼ .02), extremely preterm and term (T1 relaxation time/T2 relaxation time: P , .001), and preterm and term infants (T1 relaxation time: P , .001/T2 relaxation time: P ¼ .006). CONCLUSIONS:Quantitative MR parameters allow preterm and term neonates to be differentiated. T1 and T2 relaxation time metrics of the midbrain allow differentiation between the different stages of prematurity. SyMRI allows for a quantitative assessment of incomplete brain maturation by providing tissue-specific properties while not exceeding a clinically acceptable imaging time.

Purpose The purpose of this study was to assess the diagnostic accuracy of T1-weighted and T2-weighted contrasts generated by the MR data postprocessing software SyMRI (Synthetic MR AB, Linköping, Sweden) for neonatal brain imaging. Methods In this study 36 cases of neonatal MRI were retrospectively collected, which included T1-weighted and T2-weighted sequences as well as multi-dynamic multi-echo (MDME) sequences. Of the 36 neonates 32 were included in this study and 4 neuroradiologists independently assessed neonatal brain examinations on the basis of conventional and SyMRI-generated T1-weighted and T2-weighted contrasts, in order to determine the presence or absence of lesions. The sensitivity and specificity of both methods were calculated and compared. Results Compared to conventionally acquired T1 and T2-weighted images, SyMRI-generated contrasts showed a lower sensitivity but a higher specificity (SyMRI sensitivity 0.

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