Three-Dimensional First-Trimester Transvaginal Diagnosis of Alobar Holoprosencephaly Associated with Omphalocele in a 46,XX Fetus

ABSTRACT

A three-dimensional (3D) transvaginal diagnosis of alobar holoprosencephaly (HPE) with associated omphalocele is reported at 12 weeks, 3 days gestation. Diagnosis of HPE was based on visualization of a single holoprosencephalic cavity with absent falx and basal ganglia and omphalocele by the presence of abdominal wall defect with mid-gut herniation. Chorionic villus sampling showed a normal 46,XX karyotype. 3D volumetric reconstruction allowed a more detailed definition of the anatomic landmarks of the lesion, including visualization of a thin rim of cortical mantel within the prosencephalic cavity, the dysmorphic face with flattened nose, and the abdominal eventration that looked like an abdominal air bag on 3D volumetric reconstruction.

KEYWORDS

Three-dimensional transvaginal ultrasound - holoprosencephaly - omphalocele - fetal karyotype - prenatal counseling

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