Exencephaly is a type of cephalic disorder wherein the brain is located outside of the skull. This condition is usually found in embryos as an early stage of anencephaly. As an exencephalic pregnancy progresses, the neural tissue gradually degenerates.[1]
The prognosis for infants born with exencephaly is extremely poor. It is rare to find an infant born with exencephaly, as most cases that are not early stages of anencephaly are usually stillborn. Those infants who are born with the condition usually die within hours or minutes.[2] The disorder is caused by the failure of cranial neuropore to properly fuse between the 3rd and 4th week post conception. Because of this, the calvarium doesn't develop/fuse properly and the brain extrudes from the cranium.