Objective To estimate the utility of first-trimester 3D placental volume and vascular flow indices in the prediction of adverse pregnancy outcomes. Methods A prospective cohort study including women with singleton pregnancies seen between 11 – 14 weeks’ as part of a screening program for aneuploidy. Placental volume and vascularization indices were obtained using 3D power Doppler imaging and the VOCAL technique. Placental volume (PV), Vascularization Index (VI), Flow Index (FI) and Vascularization Flow Index (VFI) were calculated. The adverse pregnancy outcomes investigated include preeclampsia (PE), gestational hypertension (GH) and small for gestational age (SGA). The predictive ability of each variable was evaluated using receiver-operating characteristic (ROC) curves. Results Of 388 women included, PE was seen in 30 (7.7%), GH in 37 (9.0%) and SGA in 31 (8.0%). Placental volume was not significantly different between the pregnancies with adverse outcomes and those without. The mean values of the VI and VFI were significantly lower in the pregnancies that developed PE but not in GH or SGA. The area under the ROC curve for the prediction of PE was 0.71, 0.69 and 0.70 for VI, FI and VFI, respectively. Conclusion The study confirms lower 3D power Doppler vascular flow indices in pregnancies that develop PE. The discriminatory ability of using these indices alone for predicting PE appears modest.

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Objective To estimate the association between antenatal bowel dilation and postnatal small bowel atresia in fetal gastroschisis and to establish a threshold at which the risk of adverse neonatal outcome increases. Methods A retrospective cohort study of singleton gestations with an antenatal diagnosis of gastroschisis seen in our ultrasound unit from 2001-2010. Stored images were reviewed, blind to postnatal diagnoses and outcomes, from the last ultrasound exam before delivery. Fetal intra- and extra-abdominal bowel dilation as well as bowel wall thickness was measured. Previously published definitions of bowel dilation including >6mm, >10mm, >14mm and >18mm were evaluated for association with the primary outcome of bowel atresia. The optimal threshold to define fetal bowel dilation was determined by evaluating the significance of association as well as test performance characteristics. Results Of 109 consecutive patients with fetal gastroschisis, there were 4 cases of intrauterine fetal demise and 3 neonatal deaths. Of the 94 live births with complete outcome data, 39 (41.5%) had measurable intra-abdominal bowel dilation (IABD). There were 14 (14.9%) cases of bowel atresia. Using a threshold of >14mm, IABD was significantly associated with an increased risk for bowel atresia (RR 3.1, 95% CI 1.2-8.2) with a sensitivity of 57.1%, specificity of 75.0%, positive predictive value of 28.6% and negative predictive value of 90.9%. IABD >14mm was also associated with a significantly longer neonatal intensive care unit length of stay. There was no significant association between extra-abdominal bowel dilation and bowel atresia at any of the thresholds evaluated. Conclusion IABD >14mm is associated with an increased risk for postnatal bowel atresia in fetal gastroschisis. This finding may be useful in counseling patients regarding the anticipated postnatal course for their neonate.

Objective. The purpose of this study was to evaluate the reproducibility of 3‐dimensional (3D) power Doppler assessment of placental volumes and vascularization before adopting these in routine evaluation of normal and complicated pregnancies. Methods. A prospective study was performed on 30 normal singleton pregnancies from 11 to 14 weeks. To evaluate placental vascularization, 3D power Doppler sonography was applied to obtain a placental volume, and the volume acquired was analyzed using virtual organ computer‐aided analysis. Two consecutive measurements were taken from each patient by two observers blinded to each other's and the individual's previous measurement. This yielded a total of 60 data set pairs. The placental volume, vascularization index, flow index, and vascularization‐flow index (VFI) were calculated. Normal distribution of the data was confirmed with the Kolmogorov‐Smirnov test. Intraobserver and interobserver correlations were evaluated. Bland‐Altman plots and statistics were used to compare the 95% limits of agreement between measurements. Results. All 3D power Doppler placental volumes and vascular indices showed intraobserver correlations of 0.80 or higher. Similar excellent interobserver correlations were seen for all indices with the exception of the VFI, which showed a lower but acceptable correlation. The Bland‐Altman analyses indicated good reproducibility of the evaluated placental indices. Conclusions. Our findings provide validation of the technique, showing good reproducibility of the 3D power Doppler parameters when applied to studies of the placental volume and vascular tree.

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