Fetal ventriculomegaly: Investigating additional brain abnormalities by using MR imaging

Background and Purpose: Fetal ventriculomegaly (VM), is known to have a prevalence of association with other brain abnormalities. By using in utero MR imaging (iuMR), we aimed to determine the prevalence of brain abnormalities other than VM and investigate the hypothesis that the prevalence of having additional brain abnormalities (ABA) increases with the degree of VM. Materials and Methods: We reviewed iuMR images of 75 fetuses. The enlarged ventricles were graded as mild (≤ 12mm), moderate (> 12 to ≤15mm), and severe (> 15mm). Prevalence of having ABA were calculated and compared among groups with different grades of VM. Results: ABA was shown in 67% of fetuses. The most frequent ABA was agenesis of the corpus callosum. The prevalence of having ABA increased with the degree of fetal VM in all groups. Severe VM was associated with a higher prevalence of ABA when compared with mild VM in the prevalence of having ABA being present when compared with mild VM. Conclusions: The prevalence of having ABA increases with the degree of fetal VM. Caution should be exercised that this trend of ABA does not apply to those fetuses with isolated VM by sonography due to the different subjects studied.