Fetal Acrania. (A) Gray scale ultrasound of the fetus (3.5 MHz probe) in sagittal plane. Gestational age 30 weeks. White arrows = Normal looking spine. Fetal brain is seen floating in the amniotic fluid now placed posterior to the cervical spine without covering skull. Asterisk denotes craniocervical junction. (B) Coronal gray scale ultrasound scan showing normal orbits. No skull is seen around the brain. Small Arrows = Inferior Interhemispheric Fissure. Arrows = Orbits, Arrowheads = Fetal brain lacking covering skull.

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Acrania

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Radiological findings:

-Abscense of the cranial bones with the presence of complete but abnormal cerebral hemispheres(acrania or exencephaly).

-If the brain was degenerated due exposure to amniotic fluid(anencephaly).