Four-dimensional fetal echocardiography with spatiotemporal image correlation (STIC): A systematic study of standard cardiac views assessed by different observers

Objective.?To test the agreement between observers and reproducibility of a technique to display standard cardiac views of the left and right ventricular outflow tracts from four-dimensional volume datasets acquired with Spatiotemporal Image Correlation (STIC).

Methods.?A technique was developed to obtain dynamic multiplanar images of the left ventricular outflow tract (LVOT) and right ventricular outflow tract (RVOT) from volume datasets acquired with STIC. Volume datasets were acquired from fetuses with normal cardiac anatomy. Twenty volume datasets of satisfactory quality were pre-selected by one investigator. The data was randomly assigned for a blinded review by two independent observers with previous experience in fetal echocardiography. Only one volume dataset was used for each fetus. After a training session, the observers obtained standardized cardiac views of the LVOT and RVOT, which were scored on a scale of 1 to 5, based on diagnostic value and image quality (1?=?unacceptable, 2?=?marginal, 3?=?acceptable, 4?=?good, and 5?=?excellent). Median scores and interquartile range, as well as inter- and intraobserver agreement were calculated for each view.

Results.?The mean menstrual age at the time of volume acquisition was 25.5?±?4.5 weeks. Median scores (interquartile range) for LVOT images, obtained by the first and second observers, were 3.5 (2.25–5.00) and 4 (3.00–5.00), respectively. The median scores (interquartile range) for RVOT images obtained by the first and second observers were 3 (3.00–5.00) and 3 (2.00–4.00), respectively. The interobserver intraclass correlation coefficient for the LVOT was 0.693 (95% CI 0.380–0.822), and 0.696 (95% CI 0.382–0.866) for the RVOT. For the intraobserver agreement analysis, observer 1 gave higher scores to the LVOT the second time the volumes were analyzed [LVOT: 3.50 (2.25–5.00) vs. 5.00 (4.00–5.00, p?=?0.008)].

Conclusion.?STIC can be reproducibly used to evaluate fetal cardiac outflow tracts by independent examiners. Slightly better image quality rating scores during the intraobserver variability trial suggests the presence of a learning curve for the manipulation and analysis of volume data obtained by STIC.     

Four-dimensional fetal echocardiography with spatiotemporal image correlation (STIC): a systematic study of standard cardiac views assessed by different observers.

OBJECTIVE: To test the agreement between observers and reproducibility of a technique to display standard cardiac views of the left and right ventricular outflow tracts from four-dimensional volume datasets acquired with Spatiotemporal Image Correlation (STIC). METHODS: A technique was developed to obtain dynamic multiplanar images of the left ventricular outflow tract (LVOT) and right ventricular outflow tract (RVOT) from volume datasets acquired with STIC. Volume datasets were acquired from fetuses with normal cardiac anatomy. Twenty volume datasets of satisfactory quality were pre-selected by one investigator. The data was randomly assigned for a blinded review by two independent observers with previous experience in fetal echocardiography. Only one volume dataset was used for each fetus. After a training session, the observers obtained standardized cardiac views of the LVOT and RVOT, which were scored on a scale of 1 to 5, based on diagnostic value and image quality (1=unacceptable, 2=marginal, 3=acceptable, 4=good, and 5=excellent). Median scores and interquartile range, as well as inter- and intraobserver agreement were calculated for each view. RESULTS: The mean menstrual age at the time of volume acquisition was 25.5+/-4.5 weeks. Median scores (interquartile range) for LVOT images, obtained by the first and second observers, were 3.5 (2.25-5.00) and 4 (3.00-5.00), respectively. The median scores (interquartile range) for RVOT images obtained by the first and second observers were 3 (3.00-5.00) and 3 (2.00-4.00), respectively. The interobserver intraclass correlation coefficient for the LVOT was 0.693 (95% CI 0.380-0.822), and 0.696 (95% CI 0.382-0.866) for the RVOT. For the intraobserver agreement analysis, observer 1 gave higher scores to the LVOT the second time the volumes were analyzed [LVOT: 3.50 (2.25-5.00) vs. 5.00 (4.00-5.00, p=0.008)]. CONCLUSION: STIC can be reproducibly used to evaluate fetal cardiac outflow tracts by independent examiners. Slightly better image quality rating scores during the intraobserver variability trial suggests the presence of a learning curve for the manipulation and analysis of volume data obtained by STIC.     

Spatio-temporal image correlation (STIC) as a new screening tool for prenatal detection of congenital heart defects. The first Spanish experience

Introduction. The recent introduction of three- and four-dimensional ultrasonography opens a promising perspective in prenatal diagnosis.

Objective. To assess the use of the STIC technique as a screening tool in order to perform a “basic and extended fetal cardiac evaluation”.

Methods and material. A number of volumes are prospectively obtained during the routine morphological scan by a general sonographer in 28 patients randomly selected among those attending our unit. Afterwards, an experimented examiner in fetal echocardiography proceeds to their offline analysis. The successful rate of volume acquisition and analysis is evaluated, as well as the percentage of cases in which a “basic” or “extended” cardiac evaluation is possible through single sweep and multiplanar navigation. Cases with chromosomal anomalies, cardiac abnormalities or extracardiac malformations are excluded.

Results. A number of 58 volumes are included, with gestational ages ranging between 17 and 35 weeks. STIC acquisition was possible in all cases. A “basic cardiac study” was achieved in 100% of cases, while an “extended cardiac study” was achieved in 86% of them. Multiplanar study improved the visualization of those structures not identifiable through the initial acquisition single plane in all cases.

Conclusions. We present the first study on a nationwide scale about the introduction and applications of the STIC technology. STIC volumes can be obtained by operators inexperienced in fetal echocardiography and their offline analysis enables recognition of most of the structures and views necessary to assess fetal cardiac anatomy.     

Cardio-STIC (spatio-temporal image correlation) as genetic ultrasound of fetal Down syndrome

Objective: To evaluate efficacy of cardio-STIC in detection of fetal Down syndrome.

Methods: Cardio-STIC volume datasets (VDS) were prospectively collected from women during 16–22 weeks, consisting of 40 VDS acquired from fetuses with Down syndrome and 400 VDS from normal fetuses. All VDS were blindly analyzed.

Results: Between both groups, most dimensions were comparable but the right-sided dimensions were significantly greater in fetuses with Down syndrome. Interestingly, shortening fraction was also significantly higher in affected fetuses. Right-to-left disproportion and shortening fraction were used as cardiac markers as well as other eight structural markers to predict fetal Down syndrome. Tricuspid regurgitation had highest sensitivity (30%); followed by VSD (27.5%), right-to-left disproportion (20.0%), and echogenic intra-cardiac foci (EIF; 17.5%). If the test was considered positive in case of the presence of any cardiac marker, cardio-STIC had a detection rate of 72.5% and false-positive rate of 19.5%. Likelihood ratio of each marker for modifying priori risk was also provided.

Conclusion: Cardio-STIC as genetic ultrasound for Down syndrome had a detection rate of about 70% and false-positive rate 20%. Cardio-STIC analysis can be helpful in estimation of fetal risk for Down syndrome and counseling when the prenatal diagnosis of the syndrome is made.     

The severity of hypoxic changes and oxidative DNA damage in the placenta of early-onset preeclamptic women and fetal growth restriction

Objective: To investigate the relation between the severity of hypoxic changes and oxidative DNA damage in the placenta of early and late-onset preeclampic women and fetal growth restriction (FGR), serum parameters of oxidative stress, placental hypoxic change, and oxidative DNA damage were determined. Methods: We examined 10 participants with uncomplicated pregnancies, 13 with early-onset and 12 with late-onset preeclampsia. Maternal and umbilical plasma derivatives of reactive oxygen metabolites (d-ROMs) were measured as markers of oxygen free radicals. Immunohistochemical analysis was performed to measure the proportion of placental trophoblast cell nuclei staining positive for 8-hydroxy-2’-deoxyguanosine (8-OHdG), redox factor-1 (ref-1), and hypoxia-induced factor-1α (HIF-1α), which are markers of oxidative DNA damage, repair functions, and hypoxia status, respectively. Results: 8-OHdG was higher in both preeclamptic groups, but significantly higher in the early-onset preeclamptic group. Ref-1 was higher in the late-onset preeclamptic group. HIF-1α was higher in both preeclamptic groups, with a tendency towards a higher in the early-onset preeclamptic group. Conclusions: Our findings indicate that the severity of hypoxic changes and oxidative DNA damage are greater in the placenta of women with early-onset preeclampsia, and that the prolonged preeclamptic conditions may reduce placental blood flow, ultimately leading to FGR.     

Heart stroke volume,cardiac output,and ejection fraction in 265 normal fetus in the second half of gestation assessed by 4D ultrasound using spatio-temporal image correlation

Objectives.?The aim of this study was to establish nomograms for fetal stroke volume (SV), cardiac output (CO), and ejection fraction (EF) using four-dimensional ultrasound with spatio-temporal image correlation (STIC) modality.

Methods.?The fetal heart was scanned using STIC modality, starting with classic four-chamber view plane, during fetal quiescence with abdomen uppermost, at an angle of 20–30°, without color Doppler flow mapping. In post-processing virtual organ, computer-aided analysis technique was used to obtain a sequence of six sections of each ventricular volume in end-systolic volume (ESV) and end-diastolic volume (EDV). The SV (SV?=?EDV–ESV), CO (CO?=?SV?×?fetal heart rate), and EF (EF?=?SV/EDV) for each ventricle were then calculated. Intra- and interobserver agreement were then calculated.

Results.?Two hundred sixty-five fetuses, ranging in gestational age (GA) from 20 to 34⁺⁶ weeks, were included in the study. The left and right SV and CO increased exponentially with gestation and EF remained fairly stable through gestational. Mean left and right SV increased from 0.211?ml and 0.220?ml at 20 weeks to 1.925?ml and 2.043?ml, respectively, at 34 weeks. Mean left and right CO increased from 30.25 ml/min and 31.52 ml/min at 20 weeks to 268.49 ml/min and 287.80 ml/min, respectively, at 34 weeks. Both left and right mean EF remained constant at around 0.63 with advancing GA. Nomograms were created for LSV, RSV, LCO, RCO, LEF, and REF vs. gestational age. Intra- and interobserver agreement reached 95%.

Conclusions.?Four-dimensional ultrasound using STIC represents a simple and reproducible method for estimating fetal cardiac function. STIC seems to overcome many of the pitfalls of conventional ultrasound methods and has the potential to become the method of choice.     

The MCA Doppler and its role in the evaluation of fetal anemia and fetal growth restriction

Doppler velocimetry of the middle cerebral artery (MCA) has played a major role in fetal medicine for the last 23 years, both in intrauterine growth-restricted (IUGR) and anemic fetuses. Its utility in the diagnosis and management of cases of fetal anemia was initially demonstrated in cases of red cell alloimmunization and later extended to other types of anemia. In addition, MCA Doppler studies are crucial in the evaluation of IUGR fetuses. This article is a review of the role of the MCA in these 2 conditions.     

The new 3D/4D based spatio-temporal imaging correlation (STIC) in fetal echocardiography: a promising tool for the future

Abstract

Congenital heart disease is the commonest congenital anomaly. It is much more common than chromosomal malformations and spinal defects. Its’ estimated incidence is about 4–13 per 1000 live births. Congenital heart disease is a significant cause of fetal mortality and morbidity. Antenatal diagnosis of congenital heart disease is extremely difficult and requires extensive training and expertise. The detection rate of congenital heart disease is very variable and it ranged from 35 to 86% in most studies. In the light of the above, the introduction of the new 3D/4D based spatio-temporal Image Correlation (STIC) is highly welcomed to improve antenatal detection of congenital heart disease. STIC is an automated device incorporated into the ultrasound probe and has the capacity to perform slow sweep to acquire a single 3-dimensional (3D) volume. This acquired volume is composed of a great number of 2-dimension (2D) frames. This volume can be analyzed and reanalyzed as required to demonstrate all the required cardiac views. It also provides the examiner with the ability to review all images in a looped cine sequence. This technology has the ability to improve our ability to examine the fetal heart in the acquired volume and decrease examination time. Using this technique you can share the information and consult colleagues both at your clinical sitting or remotely using the internet.     

Placental gene expression of the placental growth factor (PlGF) in intrauterine growth restriction

Objective: We analyzed changes in gene expression of placental growth factor (PIGF) in human placental samples obtained postpartum from pregnancies with IUGR.

Methods: During a twelve-month study period representing the calendar year of 2012 placental samples from 101 pregnancies with IUGR and from 140 normal pregnancies were obtained for analysis of a potential difference in PIGF gene expression.

Results: There was no significant difference in gene activity of the PIGF gene between the IUGR versus normal pregnancy groups (Ln2^α: 0.92; p?α: 0.72; p?=?0.05). Placental PIGF gene activity was significantly lower in fetuses with more severe IUGR versus less severe cases (Ln2^α: ?1.49; p?Conclusion: We found no difference in gene expression of PIGF in placental samples obtained from IUGR pregnancies versus normal pregnancy suggesting the absence of a direct role of PIGF gene activity in the development of defective angiogenesis in IUGR during the later stages of gestation. However, in more severe cases of intrauterine growth restriction PIGF expression does show a significant decrease indicating its potential role in the profound defect in angiogenesis in these cases.     

胎儿生长受限的关键期及其影响子代学习记忆的行为学研究

目的 探讨腹腔注射更生霉素和被动吸烟两种因素分别作用于不同孕期时诱发胎儿生长受限(fetal growth restriction,FGR)的时相特点及FGR对子代学习记忆力的影响;观察FGR子鼠体重增长特点. 方法 腹腔注射更牛霉素和被动吸烟两种方法建立大鼠FGR动物模型;Morris水迷宫检测FGR子代不同发育期空间学习记忆能力. 结果 两种方法均成功建立FGR动物模型,其FGR发病率分别为53.47%和35.53%,和对照组比较均有统计学意义(P＜0.05).妊娠早、中、晚期分别给孕鼠腹腔注射更生霉索,FGR发病率分别为:26.2%、47.7%、46.5%,中期和晚期比较无显著性差异,中、晚期和早期有显著性差异;妊娠早、中、晚期分别给孕鼠被动吸烟,FGR发病率分别为:20.9%、40%、45.7%,中期和早期、晚期比较均有显著性差异,早期和晚期比较无显著性差异.水迷宫实验中,FGR子鼠寻找站台所需时间明显长于对照组;定位航行时FGR子代通过站台区的次数明显少于对照组.FGR子鼠生后体重增长速度比对照组快,但体重始终未明显超过对照组. 结论 对妊娠不同时期的大鼠给予被动吸烟或腹腔注射更生霉素均可建立FGR动物模型.妊娠中、晚期是诱发FGR的关键期.FGR子代学习记忆能力均受到不同程度损害.FGR子代存在体重追赶现象.     

A modified prenatal growth assessment score for the evaluation of fetal growth in the third trimester using single and composite biometric parameters

Objective: To define modified Prenatal Growth Assessment Scores (mPGAS) for single and composite biometric parameters and determine their reference ranges in normal fetuses.

Methods: Nine anatomical parameters (ap) were measured and the weight estimated (EWT_a, EWT_b) in a longitudinal study of 119 fetuses with normal neonatal growth outcomes. Expected third trimester size trajectories, obtained from second trimester Rossavik size models, were used in calculating Percent Deviations (% Dev's) and their age-specific reference ranges in each fetus. The components of individual % Dev's values outside their reference ranges, designated +iapPGAS, -iapPGAS, were averaged to give +apPGAS and ?apPGAS values for the 3rd trimester. The +iapPGAS and ?iapPGAS values for different combinations of ap (c1a (HC, AC, FDL, ThC, EWT_a), c1b (HC, AC, FDL, ThC, EWT_b), c2 (ThC, ArmC, AVol, TVol), c3 (HC, AC, FDL, EWT_a)) were then averaged to give +icPGAS and ?icPGAS values at different time points or at the end of the third trimester (+cPGAS, ?cPGAS). Values for iapPGAS, ic1bPGAS, and ic2PGAS were compared to their respective apPGAS or cPGAS reference ranges.

Results: All mPGAS values had one 95% range boundary at 0.0%. Upper boundaries of 1D +apPGAS values ranged from 0.0% (HC) to +0.49% (ThC) and were +0.06%, +2.3% and +1.8% for EWT, AVol and TVol, respectively. Comparable values for ?apPGAS were 0.0% (BPD, FDL, HDL), to ?0.58% (ArmC), ?0.13% (EWT), ?0.8% (AVol), and 0.0% (TVol). The +cPGAS, 95% reference range upper boundaries varied from +0.36% (c1b) to +0.89% (c2). Comparable values for ?cPGAS lower boundaries were ?0.17% (c1b) to ?0.43% (c2).

Conclusions: The original PGAS concept has now been extended to individual biometric parameters and their combinations. With the standards provided, mPGAS values can now be tested to see if detection of different types of third trimester growth problems is improved.     

Prenatal evaluation of fetal neck masses in preparation for the EXIT procedure: the value of pulmonary Doppler ultrasonography (PDU)

Sonographic demonstration of normal tracheal diameter and breathing-related lung fluid flow at 30 weeks' gestation in a fetus with a giant neck mass confirmed patent airways, thus avoiding an EXIT procedure.     

Intrauterine growth restriction and absent or reverse end-diastolic blood flow in umbilical artery (Doppler class II or III): A retrospective study of short- and long-term fetal morbidity and mortality

OBJECTIVE: Absent or reverse end-diastolic flow (Doppler II/III) in umbilical artery is correlated with poor perinatal outcome, particularly in intrauterine growth restricted (IUGR) fetuses. The optimal timing of delivery is still controversial. We studied the short- and long-term morbidity and mortality among these children associated with our defined management. STUDY DESIGN: Sixty-nine IUGR fetuses with umbilical Doppler II/III were divided into three groups; Group 1, severe early IUGR, no therapeutic intervention (n = 7); Group 2, fetuses with pathological biophysical profile, immediate delivery (n = 35); Group 3, fetuses for which expectant management had been decided (n = 27). RESULTS: In Group 1, stillbirth was observed after a mean delay of 6.3 days. Group 2 delivered at an average of 31.6 weeks and two died in the neonatal period (6%). In Group 3 after a mean delay of 8 days, average gestational age at delivery was 31.7 weeks; two intra uterine and four perinatal deaths were observed (22%). Long-term follow-up revealed no sequelae in 25/31 (81%) and 15/18 (83%), and major handicap occurred in 1 (3%) and 2 patients (11%), respectively, for Groups 2 and 3. CONCLUSION: Fetal mortality was observed in 22% of this high risk group. After a mean period of follow-up of 5 years, 82% of infants showed no sequelae. According to our management, IUGR associated with umbilical Doppler II or III does not show any benefit from an expectant management in term of long-term morbidity.     

Pathological examination of the placenta in small for gestational age (SGA) children with or without postnatal catch-up growth

Background/objective: Approximately 10% of small for gestational age (SGA) infants fail to catch up. The relationship between postnatal growth and placental pathology in SGA infants remains unclear. Our aim was to assess the involvement of placental pathology in postnatal growth of SGA infants.

Methods: We retrospectively evaluated placental pathology and postnatal growth in single-pregnancy infants born after 37 gestational weeks in our institution, with both birth weight and length below ?2 standard deviation scores (SDS) of the normal weight and length. “Catch-up” was defined as height reaching ?2 SDS before the second birthday. Pathology of the placenta was classified into: abnormality due to maternal factors or fatal factors, villitis of unknown etiology (VUE), other abnormalities and no abnormality.

Results: Of the 33?084 infants, 142 met our criteria and 49 of them had analyzable data. The overall catch-up rate was 84%. Catch-up growth took place in all infants with no placental abnormality and only 57% of infants with abnormality due to fatal factors. There was no significant relationship between catch-up rate and other factors.

Conclusion: Placental pathology is associated with postnatal growth in SGA children born at term. Placental abnormality due to fetal factors is related to poor catch-up rate.     

Fetal size and growth velocity in the prediction of the large for gestational age (LGA) infant in a glucose impaired population

OBJECTIVES: To evaluate the performances of estimated fetal weight (EFW) and fetal growth velocity (FGV) in the prediction of birth weight>95th centile amongst women with impaired glucose tolerance (IGT); the prediction of neonatal hypoglycaemia was a secondary endpoint. STUDY DESIGN: Two hundred and forty-two consecutive women (61 type 1 diabetes mellitus, 14 type 2 diabetes mellitus, 49 gestational diabetics and 118 with impaired glucose tolerance) receiving routine care at the combined diabetes/antenatal clinic, Jessop Hospital for Women, Sheffield. EFW was routinely calculated at approximately two-week intervals in the third trimester with the last EFW prior to delivery used in the analysis. FGV was calculated from two estimates of fetal weight between 21 and 35 days apart. EFW and FGV were both expressed as standard deviation (Z) scores. RESULTS: The mean gestational age at delivery was 37 weeks (range 26-40 weeks). Sixty-five (27%) infants were of birth weight>95th centile. Mean EFW Z scores were 2.7 and 0.99 for >95th and <95th centile, respectively (p<0.001). Receiver operator characteristics (ROC) curve analysis gave area under the curve 0.8; using a cut-off Z score of 1.7 (=95.5 centile), EFW has sensitivity 80% and specificity 72% in predicting an LGA neonate (likelihood ratios 2.8 and 0.27 for positive and negative test). Mean FGV Z scores were 0.85 and 0.4 for >95th and <95th centile, respectively (p>0.05); ROC curve analysis indicated no discriminatory capacity. Estimates of fetal size and growth performed poorly in the prediction of neonatal hypoglycaemia. CONCLUSION: In routine clinical practice, EFW has limited utility in the prediction of the LGA infant. FGV does not identify the LGA infant. EFW and FGV do not predict neonatal hypoglycaemia.