COLOR DOPPLER ULTRASONOGRAPHY IN THE IDENTIFICATION OF COMMUNICATING VESSELS IN TWIN-TWIN TRANSFUSION SYNDROME AND ACARDIAC TWINS

This study evaluates the role of color Doppler ultrasonography in the identification of the communicating placental vessels in pregnancies w ith twin-twin transfusion syndrome and acardiac twins. In 18 pregnanci es with twin-twin transfusion syndrome and two with an acardiac twin, color Doppler studies of the placental vasculature were performed befo re fetoscopy for laser coagulation of the communicating vessels. In si x cases of twin-twin transfusion syndrome the placental attachment of the intertwin membrane could be visualized. Pulsatile arterial blood f low was observed from the donor to the recipient twin that disappeared after laser therapy. In both cases of acardiac twins, one communicati ng vessel with pulsatile and another vessel with nonpulsatile blood fl ow in the opposite direction could be identified. Color Doppler imagin g is unlikely to play a major role in assisting endoscopic laser separ ation of chorioangiopagus in patients with acute polyhydramnios, but i t may prove to be useful in the early identification of pregnancies at risk of developing twin-twin transfusion syndrome.