Prenatal covering of the spinal cord decreases neurologic sequelae in a myelomeningocele model.

ABSTRACT

BACKGROUND/PURPOSE: Recent experience in fetal surgery to correct myelomeningocele in humans reports an early reversion of hydrocephalus and decreased need of ventricular shunting in the first months of life; however, it has not been possible to demonstrate benefit in lower extremity function. In the present work, we have tried to ascertain the impact of cord exposure on hind limb function. METHODS: Fetal rabbits with myelomeningocele (group M), treated myelomeningocele (group T), and control animals (group C) were compared at birth regarding physical examination, somatosensory-evoked potentials of the hind limbs, ventricular morphometry, and spine histology. RESULTS: No major difference was found between groups M and T in the physical examination. Somatosensory-evoked potentials of the hind limbs were absent in group M and present in group T, although showing a longer latency period and decreased amplitude than controls. The area of the third ventricle was significantly larger in group M than in group C; in group T, it was also somewhat larger but not significantly so. Cord histology had evident changes in group M and minor changes in group T, which resembled normal group C cord. CONCLUSIONS: Prenatal covering of the spinal cord prevents central and peripheral neurologic deterioration in this animal model of myelomeningocele.