If my baby is missing the corpus callosum why is fetal surgery for myelomeningocele repair not advised?
Before mom and baby undergo fetal surgery we need to make sure they are both as safe as possible. We use the practices from and results of the MOMS Trial (Management of Myelomeningocele) as our guide for fetal myelomeningocele repair surgery. One of the requirements for the surgery during the study was a normal fetal neuroanatomical exam. Babies who are without a corpus callosum were not included in the study, so there is not enough research to prove the safety and effectiveness of the surgery for them.
The corpus callosum is the bundle of fibers that connects the right and left hemispheres of the brain. These fibers allow the two sides of the brain to communicate with each other. In rare cases a baby does not develop a corpus callosum. These children, when born and mature, possess a spectrum of clinical presentations: normal to severe mental/motor handicaps. At this juncture in fetal imaging, we are not able to tell the difference in how a child without a corpus callosum will develop. This is the primary reason for not offering prenatal repair.
This is one of the things that doctors usually look for during an ultrasound at 18 at 22 weeks gestation. If during the ultrasound it appears that the corpus callosum is missing, a fetal MRI can help confirm the diagnosis. The exact cause is unknown, but research suggests that chromosomal errors, genetics, toxic exposure, cysts, prenatal infections or metabolic disorders may contribute to the lack of the corpus callosum. It is thought that the disruption in development of the corpus callosum happens sometime during the fifth to sixteenth week of pregnancy.
The National Organization for Disorders of the Corpus Callosum is a good resource for those looking for additional information about the lack of a corpus callosum.
This article is meant for informational purposes only. It is not meant to be a substitute for medical advice, diagnosis or treatment from your physician. Always consult with your doctor with any questions you have regarding a medical condition.