Objective To explore the application value of the fast balanced steady-state gradient field echo(sBTFE)sequence with sensitivity coding for measuring the signal intensity(SI)and fetal white matter changes.Methods A sBT-FE sequence 1.5T scan was performed on 160 heterogeneous fetal brains at 21 to 39 weeks of gestation.Fetal brains were divided into four groups of A-D according to gestational age,calculated signal intensity ratios(SIRs)for bilateral prefron-tal,occipital,temporal,parietal and parietal precentral white matter regions,thalamus,cerebellum and pons for each gesta-tional age group,and group differences in SIRs of interest were assessed by ANOVA.Results The sBTFE has good CSF white matter contrast and high spatial resolution,providing optimal diagnostic reliability for imaging the fetal brain white matter(3.35±0.42).Conclusion The sBTFE sequence shows that the fetal brain white matter SIR varies with gesta-tional age,reflecting when and where the germinal matrix migrated and the temporal order of the myelination process.
In vivo fetal brain imagingWhite matter alterationSignal intensity ratioBalanced turbo field echo se-quenceBrain inter-connectivity