444: Fetoscopic laser ablation for twin twin transfusion syndrome - outcomes with a modified technique

ObjectiveFetoscopic laser ablation (FLOC) for twin-twin transfusion (TTTS) has evolved to a selective technique targeting anastomoses along the intertwin vascular equator. While this optimizes residual donor placenta compared to non-selective (NS) FLOC, TTTS recurrence up to 17% is reported, presumably from small anastomoses remaining open between coagulation points. Aim of this study was to report outcomes when the placental surface along the vascular equator is also coagulated between anastomoses (X) (equatorial dichorionization=[ED], figure).Study DesignProspective study of patients referred for FLOC. Intraoperative characteristics, outcomes, recurrence rates (twin-anemia-polycythemia [TAPS] and oligo/polyhydramnios sequence [TOPS}) were studied for ED-FLOC.Results71 twin and 1 triplet pregnancy had FLOC for TTTS. At similar stages and procedure characteristics, ED-FLOC had lower recurrence complications at identical survival rates compared to the selective technique (table).Tabled 1SelectiveED-FLOCp-valueStage 1&2/3&415 / 2219 / 160.351Gestational age20.6 (17.3-25.6)20.6 (17.2-24.3)0.436Single Survivor14 (36.8%)13 (36.1%)0.611Two Survivors23 (60.5%)23 (63.9%)0.619TAPS4 (10.4%)00.06TOPS7 (18.4%)00.008IUGR6 (15.8%)2 (5.6%)0.263Recurrence9 (23.7%)00.001 Open table in a new tab ConclusionDeliberate equatorial dichorionization along the vascular equator minimizes TTTS recurrence and offers identical survival rates compared to selective FLOC. ObjectiveFetoscopic laser ablation (FLOC) for twin-twin transfusion (TTTS) has evolved to a selective technique targeting anastomoses along the intertwin vascular equator. While this optimizes residual donor placenta compared to non-selective (NS) FLOC, TTTS recurrence up to 17% is reported, presumably from small anastomoses remaining open between coagulation points. Aim of this study was to report outcomes when the placental surface along the vascular equator is also coagulated between anastomoses (X) (equatorial dichorionization=[ED], figure). Fetoscopic laser ablation (FLOC) for twin-twin transfusion (TTTS) has evolved to a selective technique targeting anastomoses along the intertwin vascular equator. While this optimizes residual donor placenta compared to non-selective (NS) FLOC, TTTS recurrence up to 17% is reported, presumably from small anastomoses remaining open between coagulation points. Aim of this study was to report outcomes when the placental surface along the vascular equator is also coagulated between anastomoses (X) (equatorial dichorionization=[ED], figure). Study DesignProspective study of patients referred for FLOC. Intraoperative characteristics, outcomes, recurrence rates (twin-anemia-polycythemia [TAPS] and oligo/polyhydramnios sequence [TOPS}) were studied for ED-FLOC. Prospective study of patients referred for FLOC. Intraoperative characteristics, outcomes, recurrence rates (twin-anemia-polycythemia [TAPS] and oligo/polyhydramnios sequence [TOPS}) were studied for ED-FLOC. Results71 twin and 1 triplet pregnancy had FLOC for TTTS. At similar stages and procedure characteristics, ED-FLOC had lower recurrence complications at identical survival rates compared to the selective technique (table).Tabled 1SelectiveED-FLOCp-valueStage 1&2/3&415 / 2219 / 160.351Gestational age20.6 (17.3-25.6)20.6 (17.2-24.3)0.436Single Survivor14 (36.8%)13 (36.1%)0.611Two Survivors23 (60.5%)23 (63.9%)0.619TAPS4 (10.4%)00.06TOPS7 (18.4%)00.008IUGR6 (15.8%)2 (5.6%)0.263Recurrence9 (23.7%)00.001 Open table in a new tab 71 twin and 1 triplet pregnancy had FLOC for TTTS. At similar stages and procedure characteristics, ED-FLOC had lower recurrence complications at identical survival rates compared to the selective technique (table). ConclusionDeliberate equatorial dichorionization along the vascular equator minimizes TTTS recurrence and offers identical survival rates compared to selective FLOC. Deliberate equatorial dichorionization along the vascular equator minimizes TTTS recurrence and offers identical survival rates compared to selective FLOC.