Gasless Fetoscopy: A New Approach to Endoscopic Closure of a Lumbar Skin Defect in Fetal Sheep

Abstract

Objective: To develop a new endoscopic approach to the correction of a myelomeningocele-like defect in fetal sheep. Methods: The fetuses of 9 pregnant ewes, with an average gestational age of 115 days, were subjected to a 3.0 × 2.0 cm removal of the skin over the lumbar spine, performed through hysterotomy. The uterus was closed, and three 5-mm endoscopic cannulas, without valve mechanisms, were inserted. In the pilot phase (2 animals), we initially worked exclusively in the amniotic fluid space. In the study phase, we partially withdrew the fetus from the amniotic fluid to completely expose its back. By simply allowing air to enter the amniotic cavity (without gas injection), a working space was created using a uterine lift device. The skin around the defect was dissected, and a biosynthetic cellulose material was applied to cover the area. A continuous suture of the skin was performed to completely hide the material. Results: The combined air/fluid space allowed the skin to be successfully closed in 6 out of 7 cases in the study phase. All fetuses were alive at the end of the procedures. Time to complete the endoscopic part of the procedure fell from 3 to 1 h by the end of this series. Premature birth occurred in 2 of the 4 cases allowed to continue with the pregnancy. Conclusion: A new gasless fetoscopic surgery technique was developed as an alternative to current techniques used for fetal endoscopic surgery.

Keeping it simple: a “two-step” approach for the fetoscopic correction of spina bifida

“…The authors hypothesized that the separation was probably caused by the multiple trocar manipulations required throughout the procedure. This suggests that the use of our simplified closure technique [7] could reduce the occurrence of chorioamniotic membrane separation.…”

“…Since 2002, our group has been working to develop a simplified correction technique [3][4][5][6][7], to be applied using fetoscopy. The simplified technique we have developed involves a simple dissection of the skin surrounding the lesion, placement of a piece of biosynthetic cellulose (produced by bacteria) over the untouched placode, and placement of a continuous running suture to close the skin.…”

“…We have recently developed a new endoscopic approach to fetal meningomyelocele repair that we named ''gasless fetoscopy'' [7]. We have used this technique on sheep fetuses using a combination air-and-fluid medium very similar to the combined gas/fluid medium used by Kohl et al [1].…”

Comparison between two surgical techniques for prenatal correction of meningomyelocele in sheep

“…The development of less invasive surgical techniques may significantly improve the antenatal treatment of the disease. Therefore, our group successfully developed a sonoendoscopic technique using gasless fetoscopy (7) for fetal treatment. However, in order to allow endoscopic approach, the surgical technique to correct the defect itself was simplified.…”

Optical Properties of Human Amniotic Fluid: Implications for Videofetoscopic Surgery

“…Light reflection was negligible in all samples. Conclusions: Light transmission fetoscopy has been introduced, albeit to date only in an animal model [8] . While interesting and certainly worthy of further development, this concept has yet to be proven viable without a laparotomy and is limited by the immediate confines surrounding a uterine traction device which creates a local workspace.…”