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Agenesis of the Corpus Callosum

Our long experience with prenatal diagnosis and planning for optimum care allows us to offer the highest quality treatment whether intervention is indicated before or after birth.

Under the direction of Dr. Michael Harrison, the Fetal Treatment Center was the first institution to develop fetal surgery techniques. The first open fetal surgery in the world was performed at UCSF since the early 1980's. We presently have more experience with fetal surgery and endoscopic fetal intervention (FETENDO fetal surgery) than any other institution in the world. We are dedicated to fetal research and treatment innovation.

What is agenesis of the corpus callosum?

watch videoThe corpus callosum is a collection of many millions of nerve fibers in the middle of the brain. One of it’s functions is to connect the right and left side of the brain to allow for communication between the two sides, or hemispheres. The corpus callosum coordinates signals from different parts of the brain and helps us in our thinking.

illustration of agenesis of the corpus callosum Agenesis of the corpus callosum is a birth defect in which this structure in the brain is either partially or completely missing. It may occur as an isolated brain problem, in combination with other brain abnormalities, such as ventriculomegaly, or in combination with problems with other organs, such as a congenital heart defect.

Agenesis of the corpus callosum is caused by disruption to development of the fetal brain. This disruption may be related to chromosome errors, genetic factors, prenatal infections, or other factors related to the prenatal environment. In most cases, it is not possible to know what specifically caused the disruption.

What is the outcome with agenesis of the corpus callosum?

watch video Some children with agenesis of the corpus callosum have only mild learning difficulties. Intelligence in the child may be normal. Other children may have severe handicaps such as cerebral palsy, mental retardation, autism or seizure disorders. How one child falls on this spectrum depends somewhat on whether other brain development problems are detected on MRI and whether there is a problem with the child’s chromosomes.

Throughout childhood the nerve fibers of the corpus callosum continue to grow and become more efficient even through the teenage years. At that this phase in their development, children with a normally formed corpus callosum make progress in their abstract reasoning, problem solving, and their social skills mature. A child with agenesis of the corpus callosum may have kept up with his or her peers until this age; however, they may begin to fall behind in schoolwork and social functioning. Therefore, the symptoms of agenesis of the corpus callosum can become more evident as they grow into adolescence and young adulthood.

How serious is my fetus’s agenesis of the corpus callosum?

watch videoIf your doctor sees a problem with the corpus callosum, they may refer you for several tests, if they have not already been done. These include a more detailed ultrasound (often times called “Level II ultrasound” or “Fetal Survey”), amniocentesis (to look at the genetic makeup of your fetus, and to look for any signs of infection), and fetal magnetic resonance imaging (Fetal MRI).

Fetal MRI is another way to safely look at your fetus’s brain. It provides pictures of your fetus’s brain using different technology than ultrasound. Because it uses a different technology, fetal MRI can detect other problems in your fetus's brain that cannot be detected on ultrasound. We can then look at the results from all of the tests together and your physician can speak with you about the significance of these test results.

For more information on Fetal MRI please visit UCSF Baby Brain - Fetal MRI

What are my choices during this pregnancy?

There is no treatment before birth for fetuses with agenesis of the corpus callosum. Treatment after birth involves managing the child's symptoms. It is important during your pregnancy to get a detailed diagnosis (via detailed ultrasound, amniocentesis, and MRI) in order to determine if there are any additional problems. Our staff can talk to you about these test results and inform you of what challenges you may expect. If there is evidence of more severe handicaps which require long-term care, we can help direct you to the appropriate specialists.

Last Updated: 1/26/2012
Angela and Guy

Angela and Guy

The innovative procedures at FTC saved the lives of both Angela and Guy, whom were both diagnosed with severe CCAMs.

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Sam Sieber and sister
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