SIMPLIFIED PRENATAL COVERAGE OF SURGICAL MIELOMENINGOCELE IN SHEEP ALLOWS REGENERATION OF SEVERAL LAYERS OF SOFT TISSUES

Abstract

Open fetal surgery for reparation in myelomeningocele reverses Chiari II malformation and protects exposed neural elements from secondary lesion, but the technique is associated with a high rate of complications. The aim of our study was to assess whether a simple and fast technique of coverage produces the same results as a complete and longer technique of reparation in terms of neural protection.

Twelve sheep’s foetuses underwent lumbar three-level laminectomy and opening of the dura-mater on the 75th day of the gestation. Four of them were not-repaired (NR group). Eight of them underwent coverage with inert material sheet and synthetic surgical sealant on the 95th day (R group). At birth, clinical and histological examination and comparison between groups was performed.

None NR animal were able to stand or to walk nor had sphincter continence; all of them showed a wide defect of closure in the lumbar area, continuous leakage of cerebrospinal fluid (CSF), and histological neural damage; the mean vermis herniation was 75%. All R animals were able to stand and to walk and all of them showed sphincter continence; none of them showed leakage of CSF and showed coverage of the 93% of the defect; all of them showed regeneration of dura-mater, muscle and skin; the mean vermis herniation was 10%.

A simplified technique of coverage produces the same clinical results than a more complex reconstruction in a model of surgical MMC in sheep and the histological study reveals the regeneration of several layers of soft tissues.