Prenatal diagnosis of hemifacial microsomia by magnetic resonance imaging.

We present a case of hemifacial microsomia, first detected by prenatal sonography and confirmed by ultrafast magnetic resonance (MR) imaging. A 26-year-old patient was referred to our hospital at 20 weeks of gestation because of unilateral right-sided ventriculomegaly and of a possible ventriculoseptal defect (VSD). Our sonographic examination suggested a right orbital hypoplasia and a hemiatrophy of the nose. The ultrafast T2-weighted single-shot fast-spin echo MR imaging, demonstrated a right ear hypoplasia (microtia), a right orbital hypoplasia, and a right renal hypoplasia. Epibulbar dermoid or conjunctival lipodermoid were not recognized. The fetus was prenatally diagnosed as hemifacial microsomia. Termination of pregnancy was performed at 21 weeks gestation, and a male baby weighing 342g was stillborn. The baby showed facial asymmetry, including hemiatrophy of the right nose, and right ear hypoplasia. Autopsy revealed a 2mm area of VSD, agenesis of the right kidney and ureter, pancreatic and renal aberration into right adrenal gland, thymus hypoplasia and an unfixed ascending colon without intestinal malrotation. To the best of our knowledge, this is the first report of prenatal diagnosis for hemifacial microsomia using fetal MR imaging. In our case, fetal MR imaging has evolved into a powerful diagnostic tool, for the accurate prenatal diagnosis.