Proof of concept testing of a vascular closure device for use in fetal surgery.

OBJECTIVE

Prior clinical findings have demonstrated that maternal laparotomy with trans-amniotic trans-uterine suturing of the fetoscopic port site during in utero myelomeningocele repair reduces the risk of membrane rupture. However, due to laparotomy-associated morbidity, we aimed to explore the feasibility of using a vascular closure device for percutaneous trans-amniotic trans-uterine suturing.

METHODS

This IRB and IACUC-exempt study utilized 2 strategies for proof-of-concept testing of using the Abbott Perclose ProStyle Device for suture placement; 1. Ultrasound guided application on a high fidelity maternal abdominal uterus model used for fetal procedures and 2. Placement under direct visualization with sheep undergoing cesarean delivery for other research purposes. In the high-fidelity uterus model, the Abbott Perclose ProStyle device was used to place a transuterine/transamniotic stitch with accompanying video recording of the approach (https://go.screenpal.com/watch/cZfhoDVsYvW password: perclose). Regarding the second approach, at the time of a cesarean section, 12 French Checkflo cannulas were inserted into the sheep amniotic space different approaches: (1) Seldinger technique, (2) Seldinger technique insertion of Checkflo cannula and subsequent use of the Abbott Perclose ProStyle device to suture the port site after check flow removal, (3) Abbott Perclose ProStyle device utilized in what is described as a "pre-close" technique, where prior to cannula placement, trans-uterine trans-amniotic stitches are placed followed by the insertion of a 12 French Checkflo cannula over the same guidewire. Samples of the sutured uterine wall were sent to pathology and H&E staining was performed to assess uterine hole closure and amnion-to-uterus fixation.

RESULTS

The high-fidelity model confirmed that the Perclose ProStyle Device was easily visualized by ultrasound and suture deployment was without complication. In the animal model, the Perclose ProStyle device effectively sutured the amnion to the uterus in both the pre- and post-close approach. The pre-close technique achieved better amnion-to-uterus approximation and more appropriate uterine hole closure. H&E staining revealed that without suturing, amnion separation from the chorion layer occurred, and the uterine hole persisted. The post-close technique showed partial connection between the amnion and chorion, but inadequate uterine hole closure with amnion shift into the defect. Optimal closure, with secure amnion-to-chorion fixation and uterine closure, was achieved through the pre-close technique.

CONCLUSION

The Abbott Perclose ProStyle Device seems to be a feasible device for use of uterine port closure in maternal-fetal surgery, larger animal studies with mid-pregnancy application are needed to further validate or refute these findings.