A health condition that causes a birth defect in which the spine and spinal canal of the baby do not close properly before birth is called myelomeningocele. This disorder is a type of spina bifida, and physicians can diagnose it during pregnancy. Sometimes, they are able to perform surgery during pregnancy to repair this opening in the spine.
In other words, myelomeningocele is a congenital disorder that negatively affects the child’s backbone and spinal canal. Furthermore, it is also considered a type of neural tube defect (NTD). It often appears in the first 4 weeks of pregnancy, and it is characterized by incomplete neural tube closure, which causes the fluid-filled sac to protrude from the baby’s back. Typically, the sac contains:
- Nerves
- Cerebrospinal fluid (CSF)
- Meninges (a protective layer of the spinal cord)
- A part of the spinal cord
While it may appear anywhere in the fetus’s spine, it often occurs in the low back (lumbar or sacral region). In babies with this disorder, a part of the spinal cord and nerves in the sac are damaged. As a result, it may cause weakness or loss of sensation in the affected part of the body.
It is important to understand that myelomeningocele is a more serious condition than spina bifida because it causes moderate to severe disabilities (including loss of bowel and bladder control, muscle weakness, and paralysis). Commonly, when a myelomeningocele appears in the lower part of the spine, it causes milder symptoms.
How Common is Myelomeningocele?
This disorder is one of the most common congenital central nervous system conditions. It affects more than 1,500 babies in the U.S. each year.
Symptoms
While the primary symptom of myelomeningocele is a fluid-filled sac that appears on the mid- to low-back along the spine, it may also cause other symptoms. Furthermore, babies with this congenital birth defect may also have other congenital disorders. For instance, approximately 80% of babies with this disorder also have hydrocephalus (fluid buildup in the brain). Syringomyelia (a fluid-filled cyst within the spinal cord) and hip dislocation may also occur, but it is less common. Check some general symptoms of myelomeningocele below:
- Lack of sensation in the legs or feet
- Paralysis
- Muscle weakness
- Urinary incontinence
- Scoliosis (curved spine) and other orthopedic problems
- Chiari malformation type II – It may cause breathing problems, difficulty swallowing, and arm weakness.
- Learning issues
- Seizures
- Skin sores
If your child has any of the symptoms listed above, immediately contact your healthcare provider. Otherwise, it may lead to life-threatening complications.
Causes and Risk Factors
Nowadays, experts do not know the exact cause of myelomeningocele. However, they think it is a combination of genetic, nutritional, and environmental factors. For instance, reduced levels of Folic acid during pregnancy could play a role in this congenital birth defect. This is an important vitamin for the development of the brain and spinal cord.
Physicians have identified some factors that could increase the risk of myelomeningocele. Examples include:
- Folate deficiency – This is a natural form of vitamin B9, which is very important for healthy fetal development. If a pregnant woman does not have enough folate during pregnancy, it may lead to an increased risk of spina bifida and other NTDs. Talk with your doctor about prenatal vitamins and other nutrients.
- A family history of neural tube defects – If you have other children who have neural tube defects, there is an increased risk of having other children with the same defect. Furthermore, the risk of NTDs increases even more if the pregnant woman was born with birth defects. At the same time, most babies with NTDs do not have a family history of these disorders.
- Anti-seizure medicines – Some types of this group of medications are linked to an increased risk for NTDs.
- Diabetes – This health condition may also increase the risk of your baby developing myelomeningocele, especially if it is left untreated.
- Obesity
- Increased body temperature – It is not recommended to use saunas or hot tubs because it significantly increases the risk of birth defects.
What Are The Possible Complications of Myelomeningocele?
There are some complications that babies with this disorder may experience. Check some examples below:
- An increased risk for meningitis
- Urinary tract infections (UTIs)
- Seizures
- Cognitive impairments
- Loss of bowel or bladder control
- Orthopedic problems that are often associated with paralysis. These include scoliosis, contractures, and hip dislocation.
- Mobility problems
- Latex allergy
- Tethered spinal cord
- Skin breakdown (including chronic ulcers)
This article does not contain a full list of complications, but you can talk with your doctor about ways to reduce the risk of developing them.
Diagnosis
Sometimes, physicians can diagnose this disorder during pregnancy by performing the following tests and procedures. These include:
- Blood tests – These tests are used to measure the amount of alpha-fetoprotein (AFP) in the blood during the 16th to 18th week of pregnancy. Commonly, the amount of AFP is higher in about 75% to 80% of pregnancies that carry a fetus with spina bifida.
- Fetal ultrasound – Generally, this is the more accurate test used to diagnose myelomeningocele. Usually, doctors perform this test during the first or second trimester.
- Amniocentesis – When fetal ultrasound confirms myelomeningocele, doctors may perform this test to exclude other genetic disorders that are often associated with this congenital birth defect.
If this disorder is not diagnosed during pregnancy, doctors will perform some imaging tests after birth to confirm or rule out this disorder. They often perform MRI (magnetic resonance imaging) scans or CT (computed tomography) scans.
Treatment
Almost everyone who develops myelomeningocele requires a healthcare team. These include fetal surgeons, neurologists, neurosurgeons, orthopedists, dermatologists, physical therapists, and others. While the primary treatment for babies with myelomeningocele is surgery, doctors may also recommend other options. These include:
- Antibiotics
- Ventriculoperitoneal (VP) shunt to help drain extra fluid from the brain
- Physical therapy
Frequently Asked Questions
What is the life expectancy of people with myelomeningocele?
With early diagnosis and proper treatment, people live until their 40s, 50s, or beyond. In any case, the mortality rate is still high in people with myelomeningocele, especially in the first 5 years after diagnosis.
What is a neural tube defect?
This disorder is a congenital (present at birth) defect of the brain, spine, or spinal cord that often appears within the first month of pregnancy. The most common types of neural tube defects are spina bifida and anencephaly.
What is the worst type of spina bifida?
One of the most serious forms of spina bifida is myelomeningocele. It causes a fluid-filled sac that comes out of the body though and opening in the child’s back. Babies with this condition often experience serious complications (including severe disabilities). If you have any other questions, ask your healthcare provider.
