Evaluation of Cervical Elastography Strain Pattern to Predict Preterm Birth.

PURPOSE: To evaluate cervical elastography strain pattern as a predictive marker for spontaneous preterm delivery (SPTD). MATERIALS AND METHODS: In this case-control study cervical length (CL) and elastographic data (strain ratio, elastography index, strain pattern score) were acquired from 335 pregnant women (20th - 34th week of gestation) by transvaginal ultrasound. Data of 50 preterm deliveries were compared with 285 normal controls. Strain ratio and elastography index were calculated by placing two regions of interest (ROIs) in parallel on the anterior cervical lip. The strain ratio was determined by dividing the higher strain value by the lower one. The elastography index was defined as the maximum of the strain ratio curve. Elastographic images were assigned a new established strain pattern (SP) score between 0 and 2 according to the distribution of strain induced by compression. RESULTS: Elastography index, SP score and CL differed between preterm and normal pregnancies (1.61 vs. 1.27, p < 0.001; SP score value of "2": n = 31 (62 %) vs. n = 36 (12.6 %), p < 0.001; CL 30.7 vs. 41.0 mm, p < 0.001; respectively). The elastography index and SP score were associated with a higher predictive potential than CL measurement alone (AUC 0.8059 (area under the curve); AUC 0.7716; AUC 0.7631; respectively). A combination of all parameters proved more predictive than any single parameter (AUC 0.8987; respectively). CONCLUSION: Higher elastography index and SP scores were correlated with an elevated risk of SPTD and are superior to CL measurement as a predictive marker. A combination of these parameters could be used as a "Cervical Index" for the prediction of SPTD.

Strain and dyssynchrony in fetuses with congenital heart disease compared to normal controls using speckle tracking echocardiography (STE).

Objective To compare myocardial strain and mechanical dyssynchrony in fetuses with congenital heart disease (CHD) to normal controls using speckle tracking echocardiography (STE). Methods In this comparative cross-sectional study 23 fetuses with CHD and 105 normal controls between 19 and 41 weeks of gestation were assessed with STE. The STE sample box was placed over the myocardium of both ventricles. The parameters of interest included the segmental strain of the left (LV-S) and right lateral ventricle wall (RV-S) and the global ventricular strain of both chambers (2C-S). In order to separately assess the LV, we placed the STE sample box over the myocardium of the LV. We calculated the strain of the LV lateral wall (LW-S), the septum (SEPT-S) and the global ventricular strain of the single LV (1C-S). Furthermore, we analyzed the differences in timing of negative peak myocardial strain between the LV and RV (two-chamber dyssynchrony, 2C-DYS) and also within the LV between the lateral wall and the septum (one-chamber dyssynchrony, 1C-DYS). Results The evaluation of strain and mechanical dyssynchrony was feasible in all cases. Compared to normal controls, fetuses with CHD showed lower segmental and global strain values and the extent of 2C-DYS and 1C-DYS was higher than in the healthy control group. Conclusion The deterioration of myocardial function in CHD can be measured with STE. The assessment of strain and dyssynchrony with STE may be useful for distinguishing fetuses with CHD from healthy fetuses.

Quantification of fetal myocardial function in pregnant women with diabetic diseases and in normal controls using speckle tracking echocardiography (STE).

Background The purpose of our study was to quantify the fetal myocardial function in pregnant women with diabetic diseases (FDM) and in normal controls (FC) using speckle tracking echocardiography (STE). Methods In this prospective study, the myocardial strain and dyssynchrony were analyzed using STE in a transversal four-chamber view in 180 fetuses (53 FDM, 127 FC) between 19 and 39 weeks of gestation. The measurements of the global and segmental longitudinal strain of both chambers (2C) and of the single left chamber (1C) were executed offline via QLab 10.5 (Philips Medical Systems, Andover, MA, USA). We assessed dyssynchrony as the time difference between peaks in strain in the mid segments of both chambers (interventricular dyssynchrony, 2C_DYS) and of the single left chamber (intraventricular dyssynchrony, 1C_DYS). Results Measurements were feasible with a high median frame rate of 199 frames/s (1st quartile: 174, 3rd quartile: 199). The global and segmental myocardial longitudinal strain of 2C and 1C were decreased and 2C_DYS and 1C_DYS were increased in pregnancies with diabetes compared to normal controls. Conclusion Our study demonstrates that fetal hearts affected by maternal diabetes mellitus (DM) show low myocardial strain values and high interventricular dyssynchrony. Two-chamber interventricular dyssynchrony has the potential to become a diagnostic marker for DM.

Assessment of the Fetal Cerebral Artery: Importance of Doppler Preset Settings.

OBJECTIVES: The Doppler assessment of the middle cerebral artery (MCA) has a central role in the monitoring of high-risk pregnancies. The objective of this study was to investigate the importance of Doppler preset settings for measurement of the peak systolic velocity (PSV) and pulsatility index (PI) of the MCA. METHODS: The PI and PSV of the MCA were determined prospectively in 350 healthy fetuses between 19 and 42 weeks of pregnancy. The first measurement of the MCA (MCA.S) was performed with the conventional settings and the second (MCA.O) with an optimized setting of the maximum achievable frame rate. For the MCA.O measurement, the width of the B-mode image and the color Doppler window were adjusted as narrowly as possible. In addition, the MCA was shown in optimized high-definition zoom. Resulting values were compared with commonly used reference values. RESULTS: The PSV and PI values and frame rates of the MCA.O setting were noticeably greater than those of the MCA.S setting (P < .001 for all). For both settings, the PSV and PI values were increased compared to common reference values. CONCLUSIONS: The assessment of the MCA with the optimized Doppler default setting yielded increased PSV and PI values compared to the commonly used measurement technique. Moreover, the resulting median curves differed from the established median reference curves. Therefore, an updated standardization for measuring the MCA should be set out, and current reference values should be adjusted.

Assessment of cervical elastography strain pattern and its association with preterm birth.

OBJECTIVE: The aim of the study was to assess the cervical strain pattern by an ultrasound elastography cervix examination and to determine its association with preterm delivery. METHODS: In this study, 30 cases resulting in preterm birth and 30 gestational age-matched controls were included. A vaginal ultrasound examination with cervical length and elastography measurement was performed. We calculated four strain ratios (SR1-SR4) of the regions of interest (ROIs) arranged in pairs in four different positions on the anterior cervical lip. The strain ratios were correlated to the outcome of spontaneous preterm delivery. The inter-observer and intra-observer variability of the strain measurement was evaluated. RESULTS: We observed an association between the value of the strain ratio that was calculated from the ROIs placed side by side in the middle of the anterior lip (SR4), and preterm delivery (P<0.001). The predictive values of cervical length and SR4 were comparable (AUC 0.7394; AUC 0.8322, respectively). The combination of cervical length and SR4 was superior in predicting preterm delivery compared to both parameters alone (AUC 0.8789). The inter-observer and intra-observer variability of data acquisition and measurement was excellent. CONCLUSIONS: Our study assesses the cervical elastography strain pattern and shows a correlation to a spontaneous preterm birth.

Fetal thymus size in pregnant women with diabetic diseases.

AIM: The aim of our study was to assess fetal thymus size in diabetic pregnancies compared with normal pregnancies. METHODS: Sonographic fetal thymus size was retrospectively assessed in 161 pregnancies with maternal diabetes and in 161 uncomplicated pregnancies matched by gestational age. The anteroposterior thymic and the intrathoracic mediastinal diameter were measured and the quotient was calculated [thymic-thoracic ratio (TT-ratio)]. In addition, we defined the quotient of the anteroposterior thymic diameter and the head circumference as thymus-head ratio (TH-ratio). The maternal diabetes cases were subdivided into three groups: (1) diet-controlled gestational diabetes, (2) insulin-dependent gestational diabetes and (3) preexisting maternal diabetes. RESULTS: TT-ratio and TH-ratio were smaller in pregnancies with maternal diabetes (P<0.001 and P<0.001, respectively). In all three maternal diabetes subgroups, the TT-ratio and the TH-ratio were lower compared with the control group (P<0.001 for each group). CONCLUSIONS: Reduced fetal thymus size seems to be associated with diabetic pregnancy. We introduce fetal thymus size as a new potential prognostic parameter for maternal diabetes.

Quantification of mechanical dyssynchrony in growth restricted fetuses and normal controls using speckle tracking echocardiography (STE).

PURPOSE: To evaluate longitudinal mechanical dyssynchrony in normally grown fetuses by speckle tracking echocardiography (STE) and to compare longitudinal mechanical dyssynchrony in fetal growth restriction (FGR) with normal controls. MATERIALS AND METHODS: A prospective study was performed on 30 FGR and 62 normally grown fetuses, including 30 controls matched by gestational age, using STE and a transversal four-chamber view. Data analysis was carried out with a high frame rate of about 175 frames/s. Dyssynchrony was analyzed offline with QLab 9 (Philips Medical Systems, Andover, MA, USA) as time differences between peaks in strain of both ventricles and the septum. Inter- and intraventricular and intraseptal dyssynchrony were obtained and inter- and intraobserver reliability was analyzed. RESULTS: Longitudinal mechanical dyssynchrony was feasible in all cases, with high inter- and intraobserver reliability. Levels of inter- and intraventricular dyssynchrony were higher in the FGR than in the control group. CONCLUSION: Speckle tracking echocardiography (STE) is a reliable technique for cardiac function assessment in the fetal heart. Interventricular dyssynchrony could be a potential parameter for early detection of subclinical myocardial dysfunction before other parameters demand intervention. The future clinical role of longitudinal mechanical dyssynchrony needs to be verified in larger studies and with a technique customized for prenatal echocardiography.

3D Ultrasound Evaluation of the Fetal Ear - Comparison of an xMatrix Probe with a Conventional Mechanical Probe.

Purpose New 3 D technologies like xMatrix probes promise superiority over conventional mechanical probes and may allow a more detailed and time-saving prenatal diagnosis. In a comparison study we evaluate fetal ears. The aim of our study was to compare the following aspects of both techniques: (1) ultrasound detail resolution, (2) raw data acquisition time (AT) and (3) influence of covariates. Materials and Methods 3 D raw data volumes of the fetal ear were collected with the V6 - 2 (V6) and with the xMatrix (X6) probe and were stored after offline customization to a single picture. Two observers scored these images independently. Furthermore, the 3 D raw data acquisition time (AT) was recorded. Concordance between observers, maternal age, body mass index (BMI), weeks of gestation and location of the placenta were evaluated. Results Data volumes of 103 patients were analyzed. The X6 detected anatomic structures like the scapha (p = 0.0146), fossa triangularis (p = 0.0075) and cymba conchae (p = 0.0025) more often. The mean AT of the X6 was shorter compared to the V6 (p < 0.0001). A placenta location in the scanning field increased the AT only for the V6 (p < 0.01). Concordance between observers was higher for the X6 in most cases. Detailed structures were less visible at the end of pregnancy for both devices. Conclusion The comparison study demonstrated clear advantages of the new xMatrix technology concerning an advanced and fast examination of detailed structures like the fetal ear. The importance of 3 D assessment in cases of fetal ear anomaly should be proven in further studies.

Fetal loss following invasive prenatal testing: a comparison of transabdominal chorionic villus sampling, transcervical chorionic villus sampling and amniocentesis.

OBJECTIVE: The aim of this study was to compare transabdominal chorionic villus sampling, transcervical chorionic villus sampling and amniocentesis with respect to their total fetal loss rates. METHODS: We retrospectively evaluated procedures of invasive prenatal testing performed during a 14-year period (2001-2014) including 936 amniocentesis procedures and 1051 chorionic villus samplings, of which 405 cases were executed transabdominally and 646 transcervically. Only singleton pregnancies before 24 weeks and 0 days of gestation where the pregnancy outcome was known were included. Fetal loss was defined as an abortion occurring either before 24 weeks and 0 days of gestation or <2 weeks after the procedure. RESULTS: The total fetal loss rates were determined to be 1.73% for transabdominal chorionic villus sampling, 2.01% for transcervical chorionic villus sampling and 1.18% for amniocentesis. No statistically noticeable differences between the total fetal loss rates of all three procedures were found (P=0.399). CONCLUSION: Our study has shown that chorionic villus sampling (either transabdominal or transcervical) and amniocentesis are equal methods for invasive prenatal testing with respect to their abortion risk.