Alternative technique for fetoscopic nd:yag laser coagulation in case of twin-twin transfusion syndrome with anterior placenta

OBJECTIVE: Nd:YAG laser coagulation is one way of treating severe Twin-Twin Transfusion Syndrome (TTS). To be performed successfully, complete visualization of the membranes and optimal inclination angle towards the target vessels is required. When the placenta is anterior, it may be difficult to achieve these conditions by percutaneous approach. We wanted to design an appropriate minimal access technique for such cases. STUDY DESIGN: A surgical trial was performed in 6 patients with severe TTS. Gestation ranged between 19 and 22 weeks. The amniotic cavity was accessed through the uterine fundus, with a flexible cannufa inserted with Seldinger technique. To allow bowel retraction a 3-to-4 cm minilaparotomy had to be made. A 1.2 mm fibrescope and a 400 jim laser fibre inside a bent sheath were introduced and laser coagulation was done using 45 Watts. Amniodrainage completed the procedure. The uterus was closed with a purse string, in order to prevent postoperative amnionleak or haemorrhage. RESULTS: In all patients we were able to see the intertwin membrane completely, and to coagulate the anastomosing vessels with a near 90° inclination angle. In 2 patients significant uterine haemorrhage was observed after removal of the trocar, which could be arrested by a suture. Mean interval from intervention till delivery was 14 weeks. In one patient, the donor twin died in utero from cardiac failure four weeks postoperatively. Eleven of 12 fetuses were born alive between 26 and 36 weeks. Two fetuses died from prematurity. No maternal complications occurred. CONCLUSION: Using a mini-laparotomy the uterine fundus could be safely exposed, allowing insertion of a flexible cannula and bent scope. Using this approach, complete visualization and coagulation of intertwin vessels could be achieved. Outcomes were similar to results from percutaneous laser coagulation with posterior or fundal placenta.