Pathophysiology of Myelomeningocele and Modern Surgical Treatment

Preview this chapter:

Pathophysiology of Myelomeningocele and Modern Surgical Treatment, Page 1 of 1

< Previous page | Next page > /docserver/preview/fulltext/9789815274493/chapter-4-1.gif

Myelomeningocele (MMC) is the most relevant clinical variant of spina bifida - a birth defect resulting in an open vertebral column. The failure of the lumbosacral neural tube to close during embryonic development may compromise the spinal cord in utero due to exposure to amniotic fluid and irritation by the uterine wall. Resulting neurological deficits may vary depending on the spinal level involved. Most neural tube defects are diagnosed in the second trimester by ultrasound. Early prenatal diagnosis allows in-utero repair to diminish neurological deficits and the need for postnatal ventricular shunting. In this chapter, the authors present a brief review of the pathophysiology of fetal MMC and the various repair options, and their associated clinical outcomes. Clinical studies suggest improved short-term neurological outcomes with percutaneous minimally invasive and intrauterine fetoscopic techniques using endoscopes compared with an open prenatal or postnatal repair. The main limitations of these modern techniques are preterm premature rupture of membranes (PPROM) and dehiscence or leakage at the MMC repair. Additional benefits may include a lower risk of preterm labor, reduced need for postnatal revisions, and improved newborn maturity with higher gestational age. Fetoscopy may also offer better management of the membranes and primary closure of uterine port sites. The long-term cognitive, behavioral, and functional outcomes of fetoscopic MMC repair have yet to be determined. While cesarean section may be required for delivery in subsequent pregnancies after traditional open prenatal MMC repair to avoid uterine rupture, fetoscopic methods with externalization of the uterus by maternal laparotomy may allow spontaneous vaginal delivery at term.