[Development of an animal model of myelomeningocele and options for prenatal treatment in Macaca mulatta].

BACKGROUND

Myelomeningocele is the most common congenital malformation of the central nervous system, with a reported incidence of 4.4-4.6 cases/10,000 live births in the U.S. Experimental studies demonstrated that the neurological deficit is not a cause for a primary defect in neurulation but is probably due to the progressive mechanical and chemical damage of amniotic liquid into the nerve tissue, which remained without protection during gestation. We undertook this study to develop an animal model in myelomeningocele in Macaca mulatta and compare the results of prenatal management between the colocations of an impermeable silicone mesh and closed with skin.

METHODS

A total of nine macaques were surgically intervened, randomly assigned between 12 and 14 weeks of gestation. A laminectomy was carried out in a fetus with bone marrow exposure. The defect was closed with skin or mesh. Three fetuses were left completely exposed. Descriptive statistics were done by ANOVA.

RESULTS

Of the four surviving fetuses (44%), none presented complications in mobility in the somatosensory evoked potential, hydrocephalus, or in sphincter control. Only one fetus developed bony deformities. The majority of time of the surgical procedure was due to the use of mesh and the least amount of time was involved in skin closing (p<0.005).

CONCLUSIONS

Macaca mulatta is an appropriate model for reproducing myelomeningocele and to evaluate the different options for prenatal management. Colocation of an impermeable silicone mesh is feasible, protecting the spine from amniotic liquid, with results similar to skin closure.