Prenatal techniques to prevent central nervous system malformations in the surgically induced model of myelomeningocele

AIM: To describe central nervous system malformations in the surgically induced model of Myelomeningocele (MMC) and their prevention using different prenatal treatments. METHODS: MMC was surgically created in 33 fetal lambs. Fifteen did not undergo fetal repair (group A). Of the lambs that did undergo repair, 10 were repaired with open two layer surgical closure (group B), 5 with fetoscopic coverage using bioglue (group C) and 3 fetoscopically using a patch (group D). All procedures were recorded and lamb brains and spinal cords were examined grossly and microscopically in coronal sections for structural organization anomalies. Histopathological changes were assessed using HE and S-100 neural marker. RESULTS: Hydrocephalus, Arnold-Chiari type II (AC-II) malformation and some neuronal migration disorders were observed in group A. Brains from group B and D were not hydrocephalic and had neither cell migration disorders nor hindbrain herniation. Group C presents mild degrees of hydrocephalus and AC-II. In group C lumbar lesion was covered by fibrous tissue. CONCLUSIONS: Some of the central nervous system abnormalities observed in human disease are present in the surgically induced model of MMC. In this model avoidance of fluid drainage using open fetal surgery limits malformation severity.