Miller-Dieker syndrome, or 17p13.3 deletion syndrome, is a rare, contiguous gene deletion syndrome characterized by type 1 lissencephaly, facial dysmorphism, seizures, and severe mental retardation. Impaired neuronal migration between 6 and 15 weeks' gestation is the underlying mechanism for lissencephaly, leading to the absence of sulci and gyri on the surface of the brain as well as abnormal cortical thickness. Heterozygous deletions in the region of chromosome 17p13.3 result in the severe phenotype of Miller-Dieker syndrome. Suspicious sonographic findings include absent parietooccipital and calcarine fissures as well as a "smooth, shallow sylvian fissure." Associated findings include ventriculomegaly, agenesis of the corpus callosum, fetal growth restriction, and polyhydramnios. Fetal MRI can be a useful adjunct for prenatal diagnosis, with the characteristic finding of a smooth brain surface with an abnormally shallow sylvian fissure. Miller-Dieker syndrome is incurable, with no known prenatal treatment options. Postnatal treatment consists largely of antiepileptic therapy for seizure control and supportive care. Suspicion for Miller-Dieker syndrome should be raised in patients with a family history and/or imaging findings relating to lissencephaly. Parental chromosomal analysis is indicated at the time of diagnosis, as 20% of deletions are inherited from a parent with a balanced chromosomal rearrangement.
|Title of host publication||Obstetric Imaging|
|Subtitle of host publication||Fetal Diagnosis and Care: Second Edition|
|State||Published - Jan 1 2018|
- 17p13.3 deletion syndrome
- LIS1 gene
- Miller-Dieker syndrome