Arastoo Vossough
Schizencephaly is a relatively rare malformation of the central nervous system without an entirely clear etiology. Clinical manifestations are diverse but often include varying degrees of developmental delay, sensorimotor impairment, and seizures. The prognosis in children with schizencephaly depends on whether they have an open or closed schizencephalic cleft, unilaterality or bilaterality of the cleft(s), location of the cleft(s), and presence or absence of other associated malformations. Increasingly, the diagnosis of schizencephaly is being made prenatally based on ultrasonography and MRI. Parents are often counseled about prognosis during pregnancy based on available information about the disease.
The impetus for investigating this topic came during one of our clinical imaging conferences, where we had a case of a fetus with open schizencephaly on MRI that was found to have only a closed cleft on postnatal imaging. In the literature, there has been this notion that the appearance of schizencephaly does not change between the time of in utero imaging and the postnatal period. The first author of the paper and I simultaneously came up with the idea to further investigate this topic at the conclusion of that conference. We included some other objectives in the study as well. We sought to find whether we can detect why some clefts close while others stay open and whether there is an association with intracranial hemorrhage. It was also not entirely clear to us how accurately prenatal imaging can delineate associated malformations, such as polymicrogyria beyond the cleft, absence of the septum pellucidum, hypoplasia of the optic nerves, and others at the gestational ages when pregnant patients are typically sent for MRI after detection of an abnormality on ultrasound. Sometimes schizencephaly and porencephalic cysts may be confused in early fetal imaging, and these patients are often counseled differently. The large fetal diagnosis and therapy referral program at our institution allowed us to undertake the study of this uncommon disorder.