Prenatal detection of the separation of the great toe, toe syndactyly, and large bilateral choroid plexus cysts in a fetus with trisomy 18.

Prenatal sonographic presentation of toe deformities is associated with fetal aneuploidies. This report presents a second-trimester fetus with large bilateral choroid plexus cysts, clenched hands, separation of the great toe, toe syndactyly, abnormal double maternal serum biochemical screening results, and trisomy 18. We suggest a careful ultrasound screening of the fetal limbs and other organs once a choroid plexus cyst has been identified. If abnormal sonographic findings are present, or if the results of the maternal serum biochemical screening are abnormal, karyotyping should be recommended.