Fetoscopic patch coverage of experimental myelomenigocele using a two-port access in fetal sheep

This study aims to assess the feasibility and the effectiveness of a fetoscopic myelomeningocele (MMC) coverage using a sealed inert patch through a two-port access, in the sheep model. Forty-four fetuses underwent surgical creation of a MMC defect at day 75 and were divided into four groups according to the MMC repair technique, performed at day 90. Group 1 remained untreated. Group 2 had an open surgery using suture of the defect. Groups 3 and 4 underwent defect coverage using a GoreA (R)-polytetrafluoroethylene patch secured with surgical adhesive (BioglueA (R)), with an open approach (group 3) and a fetoscopic one (group 4). Lambs were killed at term, and histological examinations were performed. Fetoscopic patch coverage was achieved in all the lambs of group 4. All the fetuses of group 2 had a complete closure of the defect whereas only 38% in group 3 and 14% in group 4. Fetal loss rate seems to be lower in group 4 than in groups 2 and 3. Fetoscopic coverage of MMC defect can be performed using a sealed patch through a two-port access, but the patch and glue correction may not be the ideal technique to repair fetal MMC.