What Is Encephaloceles?
Skull and brain deformities and abnormalities are typically congenital and in many cases genetic, except in cases of trauma. Diseases, disorders and abnormal development of skulls, brains and the spine range in severity from easily treatable to fatal. Genetic testing and screenings during pregnancy can help with early detection in cases of congenital abnormalities.
Encephaloceles are a rare brain disorder. Neural tube defects, characterized by sac-like protrusions of the brain and the membranes that cover it through openings in the skull, form as the brain and skull are developing. These defects are caused by failure of the neural tube to close completely during fetal development. The result is a groove down the midline of the upper part of the skull, or the area between the forehead and nose, or the back of the skull. When located in the back of the skull, encephaloceles are often associated with neurological problems.
Types of Encephaloceles
There are two types of encephaloceles: they can contain herniated meninges and brain tissue (encephalocele or meningoencephalocele) or only meninges (cranial meningocele). These bulges can vary in location and size. The most common type of encephalocele is occipital (approximately 74%), followed by parietal (13%) encephalocele.
Causes of Encephaloceles
Encephaloceles are usually dramatic deformities diagnosed immediately after birth, but occasionally a small encephalocele in the nasal and forehead region can go undetected. Encephaloceles are often accompanied by craniofacial abnormalities or other brain malformations.
Some affected children may have normal intelligence. There is a genetic component to the condition; it often occurs in families with a history of spina bifida and anencephaly.
There is a genetic (inherited) component to the condition, meaning it often occurs in families that have family members with other defects of the neural tube (such as spina bifida and anencephaly). Some researchers also believe that certain environmental exposures before or during pregnancy might be causes, but more research is needed. The Centers for Disease Control and Prevention (CDC) works with many other researchers to study factors that can Increase the risk of having a baby with encephalocele, or Impact the health outcomes of babies with encephalocele.
According to CDC findings, several factors appear to lead to lower survival rates for infants with encephalocele, including preterm (early) birth, low birthweight, having multiple birth defects, or being black or African American.
Risk Factors for Encephaloceles
There is a genetic (inherited) component to the condition of encephaloceles, meaning it often occurs in families that have family members with other defects of the neural tube (such as spina bifida and anencephaly).
CDC continues to study birth defects, such as encephalocele, and how to prevent them. For example, taking 400 micrograms of the B vitamin, folic acid, every day before and during early pregnancy can help prevent some major birth defects of the baby’s brain and spine, such as encephalocele. If you are pregnant or thinking about becoming pregnant, talk with your doctor about ways to increase your chances of having a healthy baby.
Screening for & Preventing Encephaloceles
Usually encephaloceles are found right after birth, but sometimes a small encephalocele in the nose and forehead region can go undetected. An encephalocele at the back of the skull is more likely to cause nervous system problems, as well as other brain and face defects.
Signs & Symptoms of Encephaloceles
Symptoms and associated abnormalities of encephaloceles may include:
- Hydrocephalus (excessive accumulation of cerebrospinal fluid in the brain)
- Spastic quadriplegia (paralysis of the arms and legs)
- Microcephaly (abnormally small head)
- Ataxia (uncoordinated movement of the voluntary muscles, such as those involved in walking and reaching)
- Developmental delay
- Vision problems
- Mental and growth retardation
- Seizures
Diagnosing Encephaloceles
Usually encephaloceles are found right after birth, but sometimes a small encephalocele in the nose and forehead region can go undetected. An encephalocele at the back of the skull is more likely to cause nervous system problems, as well as other brain and face defects.
Treating Encephaloceles
Encephalocele is treated with surgery to place the protruding part of the brain and the membranes covering it back into the skull and close the opening in the skull. However, neurologic problems caused by the encephalocele will still be present. Long-term treatment depends on the child’s condition. Multiple surgeries may be needed, depending on the location of the encephalocele and the parts of the head and face that were affected by the encephalocele.
Living with Encephaloceles
Babies born with an occipital encephalocele only typically have about a 55 percent survival rate and can suffer lifelong complications, including mental development delays, and an increased risk of seizures. Follow-up visits with your providers—your pediatrician, as well as physical and occupational therapists—are required to monitor development and nutrition as well as measuring growth.
To further your understanding of your diagnosis and to contribute to cutting-edge research, consider participating in a clinical trial so clinicians and scientists can learn more about causes, symptoms, treatment and prevention. Clinical research uses human volunteers to help researchers learn more about a disorder and perhaps find better ways to safely detect, treat or prevent disease.
All types of volunteers are needed—those who are healthy or may have an illness or disease—of all different ages, sexes, races and ethnicities to ensure that study results apply to as many people as possible, and that treatments will be safe and effective for everyone who will use them.
For information about participating in clinical research, visit NIH Clinical Research Trials and You. Learn about clinical trials currently looking for participants at Clinicaltrials.gov.