PERCUTANEOUS ACCESS TO THE UTERUS FOR FETAL SURGERY

In utero repair of selected life-threatening malformations in the huma n fetus is now a clinical reality, yet fetal surgery continues to pose significant risks to both the mother and the unborn child. Preterm la bor is a major problem directly related to the large uterine incision required for fetal exposure. Using technology developed for laparoscop ic surgery, we have devised instruments and techniques to perform feta l endoscopic surgery. We now report a percutaneous technique for direc t endoscopic access to the uterus. Minimally invasive fetoscopic surge ry may expand the indications for fetal surgery by decreasing fetal ri sks, facilitating intervention earlier in gestation, and reducing pret erm labor. This technique was developed in 4 fetal lambs who underwent endoscopic intervention at 105-110 days gestation (term = 145 days). Under ultrasound guidance, a 20-gauge spinal needle was advanced throu gh the maternal abdomen, uterus, and directly into the amniotic cavity . Warmed saline was infused through the needle to expand the amniotic cavity. Next, a 5-mm balloon-tipped trocar was placed percutaneously w ith ultrasound guidance into the amniotic cavity. A 5-mm laparoscope w as introduced and under endoamniotic vision two more 5-mm trocars were percutaneously placed. In all four sheep a 5-mm trocar was placed per cutaneously into the gravid uterus. The most difficult step was punctu ring through the amniotic membranes, but the sharp tip of the trocar f acilitated getting into the amniotic cavity. Excellent visualization o f the fetus was obtained with minimal uterine trauma. We have develope d a fetoscopic technique in sheep for percutaneous placement of trocar s into the uterus using ultrasound guidance. This approach allowed exc ellent visualization of the fetus with significantly less uterine trau ma than open fetal surgery and is an essential prerequisite for future fetal endoscopic interventions.