To explore the prenatal ultrasound and magnetic resonance imaging (MRI) features of Miller-Dieker syndrome and their correlation with genetic results.

A retrospective analysis was conducted to review the clinical data of 4 cases of pregnant women with Miller-Dieker syndrome fetuses who were referred to the Obstetrics and Gynecology Medical Center of Nanjing Drum Tower Hospital Affiliated to Nanjing University Medical College from November 2019 to September 2022 due to "fetal developmental abnormalities". The ultrasound screening, neurosonography, MRI examination, genetics, and pathological results were summarized and analyzed.

Prenatal ultrasound screening revealed 3 cases of intrauterine growth restriction, 2 cases of cardiac malformation, 1 case of ventriculomegaly, 1 case of subependymal cyst, 1 case of cerebellar vermis deficiency, 1 case of small head circumference, and 1 case of increased amniotic fluid. Neurosonography was further performed in two fetuses, which revealed 2 cases of lissencephaly, 1 case of partial agenesis of the corpus callosum, and 1 case of Blake's cyst in the posterior fossa, and excluded crebellar vermis deficiency in one fetus. Three fetuses underwent fetal MRI examination, which revealed 2 cases of lissencephaly, 1 case of partial agenesis, and 1 case of unclear display of the corpus callosum. All four pregnant women terminated their pregnancies, and fetal autopsy results showed 3 cases of lissencephaly, 2 cases of cardiac malformations, and 3 cases of mild facial abnormalities. Chromosome microarray detection showed different deletions in the 17p13.3 region in the 4 fetuses, involving the PAFAH1B1, YWHAE, and CRK genes. Three fetuses with PAFAH1B1 gene deletion all showed lissencephaly, and three cases with intrauterine growth restriction all showed YWHAE gene deletion.

Miller-Dieker syndrome has characteristic prenatal ultrasound features. When lissencephaly and intrauterine growth restriction are found by prenatal ultrasound, the presence of this disease should be considered. Some cases have special facial signs. All of these features are mainly related to the deletion of PAFAH1B1, YWHAE, and CRK genes in the 17p13.3 region. The addition of neurosonography may significantly improve the detection rate of complex cranial malformations and lissencephaly in Miller-Dieker syndrome fetuses.