A rare case report: The value of fetal MRI to detect diprosopus twins

Diprosopus is one of the rarest types of conjoined twins, caused by incomplete zygote separation in early pregnancy. It defines a condition with duplication of facial structures, monocephalic and 1 trunk. Early detection is difficult, but fetal MRI plays an important role in strengthening antenatal diagnosis of conjoined twin pregnancies and other major congenital abnormalities, complementing antenatal ultrasonography. A 28-year-old patient (G2P1A0) was referred from the regional general hospital for suspected malformations, including Dandy-Walker syndrome and a small mandible Antenatal 3-D ultrasound at 35 weeks revealed a single baby with macrosomia, hypoplasia of the vermis, and cleft lip with malformation of facial structures. A 3 Tesla MRI (Signa, GE Healthcare) revealed various developmental brain anomalies, including duplication of the frontotemporal lobes, corpus callosum agenesis, and small posterior fossa. The identification of 4 orbital structures raised suspicions of face duplication. This patient underwent a caesarean section and delivered a diprosopus twin baby. MRI emerged as an indispensable adjunct, complementing ultrasound in detecting congenital malformations. The success of this approach emphasizes collaborative efforts between clinicians and radiologists for accurate identification and management of complex fetal anomalies.