Abstract: Objective To investigate the prenatal ultrasonic manifestations of fetal gray matter heterotopias (FGMH) and
evaluate the optimal method its prenatal diagnosis. Methods The prenatal and postnatal ultrasound images and MRI images
were analyzed for a fetus with a definitive diagnosis of FGMH. The detection rates of FGMH by prenatal ultrasound and MRI
reported in literature were compared. Results We identified 11 reports of FGMH from 1998 to 2015, involving 43 cases with
prenatal diagnoses. Of the total of 44 cases (including our case), 32 that had been confirmed postpartum had prenatal
ultrasound and MRI data, which showed a significantly lower detection rates of FGMH by prenatal ultrasound than by MRI
(43.8% vs 93.8%, P<0.001). Conclusions Prenatal ultrasound can only detect subependymal heterotopia with characteristic
manifestations, and the detection of other types of FGMH relies on MRI, which is currently the best option for prenatal
diagnosis of FGMH.