Pseudoamniotic Band Syndrome after In Utero Intervention for Twin-to-Twin Transfusion Syndrome: Case Reports and Literature Review.

Pseudoamniotic band syndrome (PABS) is a rare iatrogenic complication that arises after invasive procedures in monochorionic twins. We report 3 cases of PABS, 2 after fetoscopic laser photocoagulation and 1 after bipolar cord coagulation. Two cases were detected antenatally by ultrasound; out of the two, one underwent successful fetoscopic release of amniotic band, which is the first report in twin pregnancy to our knowledge. In our centre, the incidence of PABS was found to be 2%. There were 25 cases of PABS reported previously, of which 12 cases with clinical details were reviewed together with our 3 cases. The fetal limbs were involved in all 15 cases, leading to constriction or amputation. The umbilical cord was involved in 2 cases, resulting in fetal death in one and pregnancy termination in the other. Antenatal detection of PABS is rare (27%; 4/15) as this requires a high index of suspicion. Serial postoperative targeted ultrasound surveillance of the fetal limbs and umbilical cord is necessary, particularly when features of septostomy or chorioamniotic membrane separation are found. Colour Doppler examination for the perfusion of the affected limb should be performed when PABS is detected. Fetoscopic release of amniotic band could salvage the fetal limb from amputation when impaired blood flow is detected.