Single-Shot Version of FLAIR Sequence in the Detection of Intraventricular Anomalies: Preliminary Experience in Fetal MR Imaging

Objective To evaluate single-shot (ss) FLAIR sequence in the detection of intraventricular anomalies in a series of fetuses showing mild-moderate ventriculomegaly at ultrasound. Subjects and Methods Fetuses with mild-moderate isolated ventriculomegaly, which underwent MR imaging between 2003 and 2014 were considered eligible. Fetuses were examined by standard MR protocol and ss-FLAIR sequence, tailored for snapshot imaging. Two paediatric neuroradiologists evaluated MR images. Results 542 cases were selected. MR imaging was performed at mean 26 weeks of gestation. ss-FLAIR sequence detected intraventricular findings, consistent with cysts in 10 cases. In 3/10 intraventricular cysts were also evident on ss-FSE T2 and FSE T1-weighted images. In no case diffusion weighted imaging was able to detect cyst. No cyst was highlighted on ss-FSE-T2 and FSE-T1-weighted images, without being visible also on ss-FLAIR. Conclusion ss-FLAIR sequence may be useful to detect intraventricular anomalies especially when fetal position or maternal obesity prevents adequate visualization by ultrasound.