What is Hydranencephaly?

Hydranencephaly is a congenital (present at birth) condition that is devastating to parents and fatal to children. When this occurs, much of the brain, including all or most of the brain’s cerebral hemispheres, has failed to develop. Instead, the brain cerebral hemispheres are replaced by fluid. There is some brain function which means some infants aren’t immediately diagnosed but over time, usually within a month or two, development of symptoms associated with hydranencephaly cannot be ignored.

There are a number of things that may be risk factors for a fetus developing this condition. Stroke in the pregnant mother may be among the highest of these. Sometimes a death of a twin in utero raises risk. Drug abuse could result in failed development of the brain. Other medical literature points to exposure to certain illnesses. What is clear is that there isn’t a single definable cause.

Symptoms of hydranencephaly may also be variable. In some infants, enough brain function is present for children to appear quite healthy at first. They may eat without trouble and seem developmentally unaffected in very early life. However, the fluid that fills the areas where the cerebral hemispheres are absent often begins to accumulate and may cause hydrocephalus. Other children can have seizures or twitching, be unable to nurse or bottlefeed, be blind or deaf, and have paralysis to some degree.

It may be impossible to treat hydranencephaly. The missing brain can’t be replaced. However, there are treatments for the various conditions associated with it. Some children get shunts to prevent or reduce fluid build up in the brain. Other treatments are given based on need, such as feeding support, medications to calm seizures and possibly occupational or physical therapy.

One of the most confusing aspects of hydranencephaly is trying to understand survival and mortality rates. Most literature on this subject repeats the statement that many children die before they reach the age of one. There is a high percentage of kids who suffer this unfortunate fate. On the other hand, there is also a fair percentage of children who live past their first year and may live into their teens or early 20s.

Children will obviously require significant support. A fair amount of mental impairment is expected, and children may need special care for their lifetimes. Parents also benefit from support since being a long-time caregiver of an ill child can be stressful and challenging at times. There are a few Internet groups that provide parent-to-parent support for those raising kids with hydranencephaly. These may be quite helpful in coping with the very difficult aspects of this condition.