Spina Bifida
Spina bifida (SPY-na BI-fi-da) is a birth defect in which the spinal column does not form properly, leaving a gap or opening in the spine.
Brian Teaches Class
As part of a sixth-grade science project, Brian chose to report on a condition called spina bifida. He showed a picture of the ring-shaped bones, or vertebrae, of the spine and demonstrated how the vertebrae protect the spinal cord and anchor muscles. He explained that in people with spina bifida, some of the bony plates that should cover the spine do not close, leaving an unprotected opening at the back of the spine.
No one in Brian's class had ever heard of spina bifida, and they all were surprised to learn that Brian had been born with it. He had a mild form of the condition, but he underwent a surgical procedure that corrected it when he was an infant. He ended his presentation by showing the small scar on his Iower back.
What Is Spina Bifida?
Spina bifida is a Latin term meaning "split spine" or "open spine." It is the most common of several birth defects called neural tube defects. The neural tube contains the cells that ultimately make the spinal cord, spine, and brain, and it develops during the first three to four weeks of pregnancy (often before a woman even knows that she is pregnant).
Spina bifida results when the sides of the neural tube fail to join together properly, leaving an open area. Often the gap occurs in the lower back at the base of the spine. The spinal cord is part of the central nervous system, which allows individuals to move and sense the world around them. Because spina bifida involves the central nervous system, it can cause a range of physical and mental problems.
Prenatal Testing for Spina Bifida
Sometimes parents can find out whether their baby has spina bifida before birth. Several commonly used tests can help to provide this information.
Maternal-Serum Alfa-Fetoprotein (AFP) Test:
This test is performed between the sixteenth and eighteenth weeks of pregnancy. Alfa-fetoprotein is a substance made by the developing fetus. Because the mother and fetus are connected via their circulatory systems, AFP from the fetus gets into the mother's bloodstream. By measuring the amount of AFP in the mother's blood, doctors get an indication of the likelihood that the fetus has certain birth defets. This test does not give a definite answer, and high levels of AFP only suggest that the fetus might have spina bifida. If AFP levels are high,doctors repeat the test. If the results are again high, doctors order other tests to confirm that the fetus has spina bifida. Many times, high AFP readings are false alarms and the baby is just fine.
Ultrasound:
Medical professionals can use ultrasound to confirm or rule out spina bifida. An ultrasound works by bouncing sound waves off of internal structures. A computer converts the returning sound waves into an image of the fetus inside the uterus. Sometimes the defect in the developing spine is visible on the ultrasound image.
Amniocentesis is a procedure medical professionals can perform between the sixteenth and eighteenth week of pregnancy. In this procedure, a needle passes through the mother's belly into her uterus to collect some of the fluid that surrounds the fetus. This fluid, called amniotic fluid, contains cells and chemicals from the fetus. In this fluid, medical professionals can measure the levels of AFP to help them determine whether the fetus may have spina bifida. Like the AFP test of the maternal blood, though, the test of the amniotic fluid does not give a definite answer.
Is Spina Bifida Always Serious?
Spina bifida is a common birth defect, but it does not always cause serious problems. At birth,the gap may be so slight that it is invisible and harmless. However, sometimes the spinal cord bulges out through the malformed vertebrae and serious neurological (nerve) problems result.
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