What is spina bifida?
If a child has a disease, during development, the neural tube does not
close completely, so the spine that protects the spine does not fully form.
This can cause physical and mental problems.
Types
There are three main types of spina bifida:
- Spina bifida occulta: This is the most
common and benign form of the defect. Many people don't even know they have it.
Here the spinal cord and nerves are usually in good condition, but there may be
a small tear in the spine. People often find out they have occult spina bifida
when they get x-rays for another reason. This type of spina bifida usually does
not cause any kind of disability.
- Meningocele: This rare type of
spina bifida occurs when a bag of cerebrospinal fluid is forced through a hole
in a child's back. Some people have no or few symptoms, while others have
bladder and bowel problems.
- Myelomeningocele: This is the most
serious type of spina bifida. Here, the baby's spinal canal opens at one or
more places in the lower or middle back, and a sac of fluid comes out. This sac
also contains part of the spinal cord and nerves, and these parts are damaged.
Symptoms
In occult spina bifida, the most obvious sign may be a tuft of hair or a
birthmark at the site of the defect. With meningocele and myelomeningocele, you
may see the sac rupture through the baby's back. In the case of a meningocele,
there may be a thin layer of skin over the sac.
Myelomeningocele usually lacks skin and exposes spinal cord tissue.
Other symptoms of myelomeningocele include:
- Weak leg muscles
- Unusually shaped feet, uneven hips, or a curved spine
- Seizures
- Bowel or bladder problems
Children may also have trouble breathing, swallowing, or moving their
hands. They may also be overweight. Symptoms largely depend on where in the
spine the problem is located and which spinal nerves are involved.
Causes
Nobody knows exactly what causes spina bifida. Scientists think it could
be a combination of environment and family history, or a lack of folic acid in
the mother's body.
But we do know that the condition is more common in white and Hispanic
children, as well as girls. In addition, women with poorly managed diabetes or
obesity may be more likely to have a child with spina bifida.
Diagnosis
Three tests can check for spina bifida and other birth defects while the
baby is still in the womb:
- Blood test: a sample of the
mother's blood is examined to determine if it contains a certain protein that
the baby makes, called alpha-fetoprotein (AFP). If the alpha-fetoprotein level
is very high, this may mean that the child has spina bifida or another neural
tube defect.
- Ultrasound: High frequency
sound waves bounce off your body tissues, creating black and white images of
your baby on a computer screen. If your child has spina bifida, you may see an
open spine or sac protruding from the spine.
- Amniocentesis: If your blood test
shows high levels of AFP but the ultrasound looks normal, your doctor may
recommend an amniocentesis. This is when your doctor uses a needle to remove a
small amount of fluid from the amniotic sac around the baby. If there is a high
level of alpha-fetoprotein in this fluid, this means that the skin around the
ovum is missing and alpha-fetoprotein has leaked into the amniotic sac.
Sometimes spina bifida is diagnosed after the birth of a child.
The doctor will likely want to take X-rays of the child's body and do an
MRI scan, which uses strong magnets and radio waves to produce more detailed
images.
Treatment
Doctors can operate on babies when they are only a few days old, or even
while they are still in the womb. If the baby has a meningocele, about 24 to 48
hours after birth, the surgeon replaces the membrane around the spinal cord and
closes the hole.
If the child has a myelomeningocele, the surgeon places the tissue and
spinal cord back into the child's body and covers it with skin. Sometimes the
surgeon also inserts a hollow tube called a shunt into the child's brain to
prevent water from accumulating in the brain. This is also done 24-48 hours
after the baby is born.
The operation can sometimes be done while the baby is still in the womb.
Before the 26th week of pregnancy, the surgeon enters the mother's uterus and
closes the opening in the baby's spinal cord. Babies who have this type of
surgery have fewer birth defects. But it is risky for the mother, and the baby
is more likely to be born prematurely.
After these surgeries, others may be needed to correct problems with the
foot, hip, or spine, or to replace a shunt in the brain. Between 20% and 50% of
children with myelomeningocele may also have what is known as progressive
attachment, where their spinal cord attaches to the spinal canal. As a child
grows, the spinal cord stretches, leading to muscle loss and bowel or bladder
problems. Surgery may also be required to resolve this problem.
Some people with spina bifida need crutches, splints, or wheelchairs to
get around, while others need a catheter to help with bladder problems.
Prevention
Studies have shown that taking a multivitamin with folic acid can
prevent spina bifida and reduce your child's risk of spina bifida and other
birth defects. Any woman who is pregnant or trying to get pregnant should get
400 micrograms per day. If you have spina bifida or have a child with spina
bifida, you should take 4,000 micrograms per day for at least 1 month before
pregnancy for the first few months.
Folic acid is also found in dark green vegetables, egg yolks, and some fortified breads, pasta, rice, and breakfast cereals.