The case for and against intrauterine surgery for myelomeningoceles.

The case for and against intrauterine surgery on a myelomeningocele depends on how and in what order the malformations in the spinal cord and brain are thought to develop. If the brain defects arise in the embryonic period and undergo no further change and if the spinal cord is so deformed that it is functionless from the start, then operative intervention before birth will have no significant effect on the ultimate neurological defect. If, on the other hand, the brain lesions evolve during gestation and the deformed spinal cord has some useful function that can be lost by contact with the amniotic fluid or is susceptible to mechanical damage, then intrauterine surgery may have a beneficial role. Long-term follow-up of children who have already undergone intrauterine surgery should answer whether this novel form of treatment imparts significant benefit to justify the risks it imposes on the mother and fetus.