In utero Repair of Myelomeningocele: Rationale, Initial Clinical Experience and a Randomized Controlled Prospective Clinical Trial

Myelomeningocele (MMC), one of the most common congenital malformations, can result in severe lifelong disabilities, including paraplegia, hydrocephalus, Arnold-Chiari II malformation, incontinence, sexual dysfunction, skeletal deformations, and mental impairment. MMC was the first nonlethal anomaly to be treated by fetal surgery. Studies in animals provide compelling evidence that the primary cause of the neurological deficit associated with MMC is not simply incomplete neurulation but rather chronic mechanical injury and amniotic-fluid-induced chemical trauma that progressively damage the exposed neural tissue during gestation. Initial results suggest that the surgical repair of MMC before 25 weeks of gestation may preserve neurological function, reverse the hindbrain herniation of the Arnold-Chiari II malformation, and obviate the need for postnatal placement of a ventriculoperitoneal shunt. As it is currently unknown whether fetal surgery for MMC is truly beneficial compared to standard postnatal care, a randomized, controlled clinical trial has been initiated within the United States.