Isolated anencephaly/exencephaly is a rare birth defect in which a baby is born without parts of the brain, skull, and scalp. It is a type of neural tube defect, which is a problem with the development of the brain, spine, or related structures that occurs very early in pregnancy. Babies born with this condition usually do not survive.

The symptoms of isolated anencephaly/exencephaly include:

-Absence of the brain and skull above the eyes
-Absence of the scalp and cranial bones
-Absence of the cerebrum and cerebellum
-Absence of the brainstem
-Absence of the eyes
-Absence of the nose
-Absence of the ears
-Absence of the scalp
-Absence of the cranial nerves
-Absence of the meninges
-Absence of the ventricles
-Absence of the choroid plexus
-Absence of the falx cerebri
-Absence of the corpus callosum
-Absence of the thalamus
-Absence of the hypothalamus
-Absence of the pituitary gland

The exact cause of isolated anencephaly/exencephaly is unknown. However, research suggests that genetic and environmental factors may play a role. Genetic factors may include mutations in certain genes, such as the MTHFR gene, which is involved in folate metabolism. Environmental factors may include exposure to certain toxins, such as alcohol, drugs, and certain chemicals. Additionally, maternal nutrition, age, and certain infections may also be associated with an increased risk of anencephaly/exencephaly.

Unfortunately, there is no treatment for isolated anencephaly/exencephaly. The condition is usually diagnosed prenatally and the pregnancy is often terminated. If the pregnancy is carried to term, the baby will usually die shortly after birth.

The risk factors for isolated anencephaly/exencephaly include:

1. Advanced maternal age (over 35 years old)
2. Low maternal folate levels
3. Maternal diabetes
4. Maternal obesity
5. Maternal smoking
6. Maternal alcohol consumption
7. Maternal exposure to certain medications or environmental toxins
8. Family history of neural tube defects
9. Genetic factors

Unfortunately, there is no cure or medication for isolated anencephaly or exencephaly. These conditions are usually fatal and most affected pregnancies are terminated.