Congenital absence of brain, also known as anencephaly, is a rare, severe neural tube defect that occurs due to the incomplete development of the brain and skull during fetal development. It is characterized by the absence of major parts of the brain and the skull, leading to the cranial vault being either missing or incomplete.
This condition typically arises early in embryonic development when the neural tube fails to close properly, usually within the first month of pregnancy. As a result, the forebrain, which includes the cerebrum, cerebellum, and other brain structures, does not develop fully or may be completely absent. The remaining brain tissue may be exposed due to the absence of the protective covering provided by the skull.
Infants born with congenital absence of brain usually possess a rudimentary brainstem that helps regulate basic autonomic functions like breathing and heartbeat. However, since the brain's higher cognitive functions are lacking or severely impaired, anencephalic infants are typically unable to survive for an extended period outside the womb. Thus, anencephaly is often detected during prenatal ultrasound, and the decision for termination of the pregnancy is frequently made.
It is important to note that congenital absence of brain is a devastating condition, both for the affected individual and their families, due to the severe physical and intellectual limitations it presents. Medical intervention is currently limited, with palliative care being the primary approach to manage the condition.
