[Creation of a model for myelomeningocele in rabbit embryos].

UNLABELLED

Spinal dysraphism causes paraplegia, fecal incontinence, neurogenic bladder, sexual dysfunction, hydrocephalus and skeletal abnormalities in newborns. Its ethiology and pathogenesis are still not known, and probably multifactorial.

AIM

To determine whether spinal cord exposition to the amniotic space causes a functional (impairment) and anatomic lesion similar to that of human myelomeningocele.

MATERIAL AND METHODS

Forty-eight fetal rabbits underwent to create spina bifida on the 23rd gestational day (term is 31 days). The procedure consisted of lumbosacral skin excision and posterior laminectomy. The fetuses are allowed to continue their gestation. On the 30th gestational by the operated fetuses were harvested, together with a group of nonoperated littermates for control. A clinical and neurologic evaluation was done, as well a study of somato-sensorial evoked potentials in the upper and lower limb and histologic study of the affected vertebral and cordial segment.

RESULTS

The 26 surviving animals had deformity and lack of movement of the lower limbs. Evoked potentials showed absent response to stimuli in the lower limbs of animals with spina bifida, whereas upper limbs and control animals did respond. Histologically the spinal cord of the operated rabbits was uncovered and flattened.

CONCLUSION

This model of myelomeningocele in fetal rabbit reproduces a variety of features similar to human spinal dysraphism, and hence can be used to study the pathophysiology of spina bifida.