The predictive value of first trimester fetal volume measurements, a prospective cohort study

Variability of bovine conceptus-related volumes in early pregnancy measured with transrectal three-dimensional ultrasonography

Up until now, bovine fetometry has been entirely based on 2-dimensional ultrasonography. Fetal size is estimated by several linear measurements such as crown-rump length (CRL). However, the advent of 3-dimensional ultrasonography (3D-US) provides in vivo access to the volumes of the fetus and its amniotic sac. The objective of this preliminary observational study was to determine the variability of conceptus-related volumes using transrectal 3D-US in dairy cows and to identify factors affecting them. Furthermore, relationships between the gained measurements and calf birth weight were investigated. In total, 315 Simmental and Holstein-Friesian dairy cows were transrectally examined at d 42 after breeding using a portable ultrasound device (Voluson I, GE Healthcare). Gestational volumes including fetal volume (FV) and amniotic sac volume (ASV) were determined with the software tool VOCAL (Virtual Organ Computer-Aided Analysis, GE Healthcare), whereas amniotic fluid volume (AFV) values were derived from the subtraction of FV from ASV. The CRL was determined by means of 3-dimensional data. The mean values and standard deviations for FV, ASV, AFV, and CRL were 1.47 ± 0.25 cm³, 5.86 ± 1.22 cm³, 4.38 ± 1.02 cm³, and 2.38 ± 0.18 cm, respectively. All gestational volumes and CRL values were affected by breed. In Simmental cattle, larger concepti were observed compared with pregnancies derived from Holstein-Friesian animals. Parity affected only ASV and AFV, with heifers showing greater values than lactating cows. The CRL was positively associated with milk protein content. It was not possible to predict calf weight at birth by using FV, ASV, or AFV; however, tendencies were found for ASV and AFV. The present study was the first to adopt 3D-US volumetry to assess early pregnancy development in dairy cattle. Our results showed that this method could be used successfully to identify minor variations in conceptus growth.

Towards Automated Semantic Segmentation in Prenatal Volumetric Ultrasound

Volumetric ultrasound is rapidly emerging as a viable imaging modality for routine prenatal examinations. Biometrics obtained from the volumetric segmentation shed light on the reformation of precise maternal and fetal health monitoring. However, the poor image quality, low contrast, boundary ambiguity, and complex anatomy shapes conspire toward a great lack of efficient tools for the segmentation. It makes 3-D ultrasound difficult to interpret and hinders the widespread of 3-D ultrasound in obstetrics. In this paper, we are looking at the problem of semantic segmentation in prenatal ultrasound volumes. Our contribution is threefold: 1) we propose the first and fully automatic framework to simultaneously segment multiple anatomical structures with intensive clinical interest, including fetus, gestational sac, and placenta, which remains a rarely studied and arduous challenge; 2) we propose a composite architecture for dense labeling, in which a customized 3-D fully convolutional network explores spatial intensity concurrency for initial labeling, while a multi-directional recurrent neural network (RNN) encodes spatial sequentiality to combat boundary ambiguity for significant refinement; and 3) we introduce a hierarchical deep supervision mechanism to boost the information flow within RNN and fit the latent sequence hierarchy in fine scales, and further improve the segmentation results. Extensively verified on in-house large data sets, our method illustrates a superior segmentation performance, decent agreements with expert measurements and high reproducibilities against scanning variations, and thus is promising in advancing the prenatal ultrasound examinations.

Three-dimensional volumetric study with VOCAL in normal and abnormal posterior fossa fetuses

Purpose: The aim of this study was to compare volumetric parameters in the abnormal and normal posterior fossa using the Virtual Organ Computer-aided AnaLysis (VOCAL™) technique to determine whether fetuses with an abnormal posterior fossa have different volumes.Methods: A prospective study was conducted on 17 fetuses with an abnormal posterior fossa including, Dandy Walker malformation (DWM) (n = 6), vermian hypoplasia (VH) (n = 3), mega cisterna magna (MCM) (n = 8), and 99 healthy control fetuses from 20 to 34 weeks' gestation. Measurement of the fetal cisterna magna and cerebellar volume was performed in the standard transcerebellar plane through the VOCAL™ method. To establish the correlation of volumes with gestational age, polynomial regression analysis was performed. For comparison between groups, univariate ANCOVA was performed using gestational age as a covariate. The reliability was analyzed by the intraclass correlation coefficient (ICC).Results: Cerebellar volume and cisterna magna volume were correlated with gestational age. Posterior fossa volume was significantly larger in DWM (p < .0001) and MCM (p < .0001) in comparison to the control group. In VH group, cisterna magna volume does not seem to expand (p = .298). Cerebellar volume does not seem to change in subgroups when the influence of gestational age is discarded (p = .09). The ratio of cerebellar volume to the cisterna magna volume decreases significantly in abnormal fetuses (p < .0001). Good intraobserver and interobserver reliabilities were found for both cerebellum and cisterna magna measurements.Conclusions: Volume analysis may have a role in discrimination of different posterior fossa pathologies.

The correlation between birth weight and insulin-like growth factor-binding protein-1 (IGFBP-1), kisspeptin-1 (KISS-1), and three-dimensional fetal volume

PURPOSE

This study aimed to determine the relationship between birth weight, and maternal serum insulin-like growth factor-binding protein-1 (IGFBP-1) and kisspeptin-1 (KISS-1) levels, and first-trimester fetal volume (FV) based on three-dimensional ultrasonography.

MATERIALS AND METHODS

The study included 142 pregnant women at gestational week 11°-13⁶. All fetuses were imaged ultrasonographically by the same physician. Maternal blood samples were collected at the time of ultrasonographic evaluation and analyzed for IGFBP-1 and KISS-1 levels via enzyme-linked immunosorbent assay (ELISA). Maternal and neonatal weights were recorded at birth. Birth weight ≤10th and the >90th percentiles was defined as small and large for gestational age (SGA and LGA), respectively.

RESULTS

Median crown-rump length (CRL), FV, and maternal serum IGFBP-1 and KISS-1 levels were 58.2 mm (35.3-79.2 mm), 16.3 cm³ (3.8-34.4 cm³), 68.1 ng mL^-1 (3.8-377.9 mL^-1), and 99.7 ng L^-1 (42.1-965.3 ng L^-1), respectively. First-trimester IGFBP-1 levels were significantly lower in the mothers with LGA neonates (p < .05). There was a significant positive correlation between CRL and FV, and between the IGFBP-1 and KISS-1 levels. IGFBP-1 levels and maternal weight at delivery were negatively correlated with neonatal birth weight. There was no correlation between CRL or FV and maternal IGFBP-1 or KISS1 levels (p > .05). The maternal IGFBP-1 level during the first trimester was a significant independent factor for SGA and LGA neonates (Odds ratio (OR): 0.011, 95%CI: 1.005-1.018, p < .001; and OR: 1.297, 95%CI: 1.074-1.566, p = .007, respectively). There was no significant relationship between SGA or LGA, and CRL, FV, or the KISS-1 level.

CONCLUSIONS

As compared to the maternal KISS-1 level, the maternal IGFBP-1 level during the first trimester might be a better biomarker of fetal growth. Additional larger scale studies are needed to further delineate the utility of IGFBP-1 as a marker of abnormal birth weight.

Three-dimensional ultrasound first trimester fetal volume measurement and its relation to pregnancy outcome

AIM OF WORK

To determine whether fetal volume (FV) measured by three-dimensional (3D) ultrasound was able to detect fetuses at risk of low birth weight (primary outcome) and/or preterm labor (secondary outcome).

METHODS

One hundred pregnant women carrying a singleton living pregnancy who were sure of dates, and had a dating scan, with gestational age between 11 weeks and 13 weeks+6 days coming for routine first trimester nuchal translucency (NT) were examined by both two-dimensional (2D) and 3D ultrasound (Vocal System) for crown-rump length (CRL) and FV then followed up regularly every 4 weeks until 28 weeks then biweekly until 36 weeks then weekly until delivery both clinically and by ultrasound biometry.

FINDINGS

Eighty-seven cases had a normal outcome, while the remaining 13 cases had either preterm labor (four cases) or low-birth weight (nine cases). FV positively correlated with CRL (P=0.026), gestational age in weeks (P=0.002), neonatal body weight in grams (P=0.018) and neonatal body length at birth (P=0.04). A mean FV of 8.3 mm3 was association with neonatal complications (P=0.045). A cut-off point of 9 mm3 for FV was associated with 100% sensitivity for detection of the date of birth, while a cut-off point of 9.15 mm3 for FV was associated 100% sensitivity for detection of neonatal birth weight.

CONCLUSION

3D assessment of FV in the first trimester provides an accurate method for predicting pregnancy outcome namely low birth weight and neonatal complications, however, it is a better positive predictor than a negative one.

First trimester screening can predict adverse pregnancy outcomes

There has been an increasing drive over the last two decades to push the detection of women at risk of adverse pregnancy outcomes into the first trimester. This has led to a plethora of techniques, risk assessments and biomarkers, both fascinating and bewildering in its breadth. Despite the vast amount of knowledge available, it is often difficult to determine what is practicable and valuable for clinical practice. This is especially true as earlier diagnosis does not necessarily equate to improved outcomes for mother and child. We suggest that, at least for preeclampsia, fetal growth restriction, spontaneous preterm birth and gestational diabetes, there are effective first trimester tests available to identify the women at risk of subsequently developing complications. Unfortunately, there are no currently reliable first trimester tests available for identifying women at risk of stillbirth. It is likely that this field will continue to develop over time, and we hope that new and better strategies will continue to emerge to target these clinically important pathologies.

Reproducibility study of fetal 3-D volumetry in the first trimester: effect of fetal size and rotational angle of VOCAL software

Intra- and inter-observer reproducibility of fetal volume measurement by 3-D ultrasound scan (using VOCAL [Virtual Organ Computer-Aided Analysis] software) in 27 fetuses at 7 to 13 wk was studied. For intra-observer variability, the mean difference (MD) and 95% limits of agreement (95% LOA) at 12°, 18° and 30° were MD(12) = 0.097, 95% LOA(12) = -0.87 to +1.06; MD(18) = 0.07, 95% LOA(18) = -1.31 to +1.45; and MD(30) = -0.07, 95% LOA(30) = -1.55 to +1.41. The standard deviation of the differences (SD(DIF)) increased with crown-rump length at 12° (p = 0.0016), 18° (p = 0.0011) and 30° (p = 0.02). For inter-observer variability, MD(12) = 0.15, 95% LOA(12) = -1.65 to +1.95; MD(18) = 0.042, 95% LOA(18) = -1.79 to +1.87; and MD(30) = 0.19, 95% LOA(30) = -1.24 to +1.62. SDDIF increased with crown-rump length at 18° (p = 0.0084) and 30° (p = 0.0073). The accuracy of fetal volume measurement was not influenced by rotational angle or fetal size. Precision deteriorated for wider rotational angles and larger fetuses.

First trimester pregnancy volumes and subsequent small for gestational age fetuses

OBJECTIVE

To examine whether in the first trimester, placental, gestational sac and fetal volumes are different in pregnancies that result in small for gestational age (SGA) compared to average for gestational age (AGA) neonates.

METHODS

Case-control study comparing first trimester 3D volumes of the placenta, the fetus and the gestational sac between SGA and AGA pregnancies. 3D volumes were acquired for quality assurance and documentation. Pregnancy volumes were calculated by the virtual organ computer-aided analysis technique. Linear regression analysis was used to compute a normal range for the placental, gestational sac and fetal volume based on the crown rump length (CRL) in AGA pregnancies. Multiple regression analysis was used to examine significant influencing covariates. A Student's t test was used to compare the difference between the SGA and AGA group.

RESULTS

The study population consisted of 19 first trimester pregnancies with subsequent SGA neonates and 105 control pregnancies. In the AGA group, all pregnancy volumes were significantly dependent on the CRL. After controlling the CRL effect, the placental, gestational sac and fetal volumes were not significantly different between the SGA and AGA group.

CONCLUSION

First trimester 3D pregnancy volume measurements are not different in SGA or AGA pregnancies.