The value of 3-dimensional color Doppler in predicting intraoperative hemorrhage for cesarean scar pregnancy

The aim of this study is to evaluate the efficacy of 3-dimensional (3D) ultrasonography and 3D color power Doppler ultrasound in the management of cesarean scar pregnancy (CSP). A case–control study enrolled 190 CSP patients who underwent uterine artery embolization (UAE) in combination with dilatation and curettage (D&C). The maximum diameter of gestational sac or CSP mass, uterine scar thickness, and resistance index (RI) were measured by 2D ultrasound. The lesion volume, vascular index (VI), flow index (FI), blood vessels, and blood flow index (VFI) were assessed by 3D ultrasound. The changes of these parameters before and after UAE were analyzed. Then, the patients were divided into bleeding group and control group according to the intraoperative hemorrhage during D&C to access and compare the significance of 2D and 3D parameters in intraoperative hemorrhage. The mean VI and the mean VFI were significantly reduced after embolization (P < .01). In the bleeding group, the lesion volume and diameter of gestational sac or CSP mass were significantly larger, VI and VFI were significantly higher, the uterine scar thickness was thinner, and RI was lower (P < .05). The best indicator for prediction of massive intraoperative bleeding was the VI with an area under the curve of 0.870, the best cut-off value of VI was 7.500, and the sensitivity and specificity were 88.2% and 82.4%, respectively. In comparing the receiver operating characteristic curves among 2D and 3D ultrasound parameters, the diagnostic efficacy of lesion volume was significantly higher than maximum diameter (P < .001). The diagnostic efficacy of VI was significantly higher than maximum diameter (P = .020) and RI (P = .011). UAE reduces the number of vessels and the blood flow perfusion obviously; however, it does not reduce lesion size or increases myometrial thickness. Three-dimensional ultrasonography and power Doppler, especially VI, lesion volume may be helpful in predicting excessive bleeding during D&C after UAE.