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Objective: To evaluate a dual-imaging modality approach to obtain a combined estimation of venous blood oxygenation (SνO2) using susceptibility-weighted magnetic resonance imaging (SWI-MRI), and blood perfusion using power Dopp-ler ultrasound (PDU) and fractional moving blood volume (FMBV) in the brain of normal growth and growth-restricted fetuses.Methods: Normal growth (n = 33) and growth-restricted fetuses (n = 10) from singleton pregnancies between 20 and 40 weeks of gestation were evaluated. MRI was performed and SνO2 was calculated using SWI-MRI data obtained in the straight section of the superior sagittal sinus. Blood perfusion was estimated using PDU and FMBV from the frontal lobe in a mid-sagittal plane of the fetal brain. The association between fetal brain SνO2 and FMBV, and the distribution of SνO2 and FMBV values across gestation were calculated for both groups.Results: In growth-restricted fetuses, the brain SνO2 values were similar, and the FMBV values were higher across gestation as compared to normal growth fetuses. There was a significantly positive association between SνO2 and FMBV values (slope = 0.38 ± 0.12; r = 0.7; p = 0.02) in growth-restricted fetuses. In normal growth fetuses, SνO2 showed a mild decreasing trend (slope = -0.7 ± 0.4; p = 0.1), whereas FMBV showed a mild increasing trend (slope = 0.2 ± 0.2; p = 0.2) with advancing gestation, and a mild but significant negative association (slope = -0.78 ± 0.3; r = -0.4; p = 0.04) between these two estimates.Conclusion: Combined MRI (SWI) and ultrasound (FMBV) techniques showed a significant association between cerebral blood oxygenation and blood perfusion in normal growth and growth-restricted fetuses. This dual-imaging approach could contribute to the early detection of fetal "brain sparing" and brain oxygen saturation changes in high-risk pregnancies. [ABSTRACT FROM AUTHOR]

Fetal dextrocardia is a type of cardiac malposition where the major axis from base to apex points to the right side. This condition is usually associated with a wide spectrum of complex cardiac defects. As a result, dextrocardia is conceptually difficult to understand and diagnose on prenatal ultrasound. The advantage of four-dimensional sonography with spatiotemporal image correlation (STIC) is that this modality can facilitate fetal cardiac examination. A novel method known as fetal intelligent navigation echocardiography (FINE) allows automatic generation of nine standard fetal echocardiography views in normal hearts by applying intelligent navigation technology to STIC volume datasets. In fetuses with congenital heart disease, FINE is also able to demonstrate abnormal cardiac anatomy and relationships when there is normal cardiac axis and position. However, this technology has never been applied to cases of cardiac malposition. We report herein for the first time, a case of fetal dextrocardia and situs solitus with complex congenital heart disease in which the FINE method was invaluable in diagnosing multiple abnormalities and defining complex anatomic relationships. We also review the literature on prenatal sonographic diagnosis of dextrocardia (with an emphasis on situs solitus), as well as tricuspid atresia with its associated cardiac features. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the performance of Fetal Intelligent Navigation Echocardiography (FINE) applied to spatiotemporal image correlation (STIC) volume datasets of the normal fetal heart in generating standard fetal echocardiography views.Methods: In this prospective cohort study of patients with normal fetal hearts (19-30 gestational weeks), one or more STIC volume datasets were obtained of the apical four-chamber view. Each STIC volume successfully obtained was evaluated by STICLoop™ to determine its appropriateness before applying the FINE method. Visualization rates for standard fetal echocardiography views using diagnostic planes and/or Virtual Intelligent Sonographer Assistance (VIS-Assistance®) were calculated.Results: One or more STIC volumes (total n = 463) were obtained from 246 patients. A single STIC volume per patient was analyzed using the FINE method. In normal cases, FINE was able to generate nine fetal echocardiography views using: (1) diagnostic planes in 76-100% of the cases, (2) VIS-Assistance® in 96-100% of the cases, and (3) a combination of diagnostic planes and/or VIS-Assistance® in 96-100% of the cases.Conclusion: FINE applied to STIC volumes can successfully generate nine standard fetal echocardiography views in 96-100% of cases in the 2nd and 3rd trimesters. This suggests that the technology can be used as a method of screening for congenital heart disease. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the intermediate intracardiac diastolic velocities in fetuses with growth restriction.Methods: Doppler waveforms of the two atrioventricular valves were obtained. Peak velocities of the E (early) and A (atrial) components, and the lowest intermediate velocity (IDV) between them, were measured in 400 normally grown and in 100 growth-restricted fetuses. The prevalence of abnormal IDV, E/IDV, and A/IDV ratios in fetuses presenting with perinatal death or acidemia at birth (pH ≤7.1) was estimated.Results: IDV was significantly lower and E/IDV ratios significantly higher in the two ventricles of growth-restricted fetuses with reduced diastolic velocities in the umbilical artery (p < 0.05). In 13 fetuses presenting with perinatal death or acidemia at birth, 11 (85%) had either an E/IDV or A/IDV ratio >95th percentile, whereas 5 (38%) showed absent or reversed atrial velocities in the ductus venosus (DV-ARAV; p < 0.04). Fetuses without DV-ARAV but with elevated E/IDV ratios in either ventricle were nearly 7-fold more likely to have perinatal demise or acidemia at birth (OR 6.9, 95% CI 1.4-34) than those with E/IDV ratios <95th percentile.Conclusion: The E/IDV and A/IDV ratios in the two cardiac ventricles might provide information about the risk of perinatal demise or acidemia in growth-restricted fetuses. [ABSTRACT FROM AUTHOR]

Objective: To examine the association between an umbilical artery notch and fetal deterioration in monochorionic/monoamniotic (MC/MA) twins. Methods: Six MC/MA twin pregnancies were admitted at 24-28 weeks of gestation for close fetal surveillance until elective delivery at 32 weeks or earlier in the presence of signs of fetal deterioration. Ultrasound (US) examinations were performed twice weekly. The presence of cord entanglement, umbilical artery notch, abnormal Doppler parameters, a non-reassuring fetal heart rate pattern, or an abnormal fetal biophysical profile were evaluated. Results: Umbilical cord entanglement was observed on US in all pregnancies. The presence of an umbilical artery notch was noted in four out of six pregnancies and in two of them an umbilical artery notch was seen in both twins. The umbilical artery pulsatility index was normal in all fetuses. Doppler parameters of the middle cerebral artery and ductus venosus, fetal biophysical profile and fetal heart rate monitoring remained normal until delivery in all pregnancies. All neonates experienced morbidity related to prematurity; however, all were discharged home in good condition. Conclusion: The presence of an umbilical artery notch and cord entanglement, without other signs of fetal deterioration, are not indicative of an adverse perinatal outcome. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The lesion termed 'placental infarction hematoma' is associated with fetal death and adverse perinatal outcome. Such a lesion has been associated with a high risk of fetal death and abruption placentae. The fetal and placental hemodynamic changes associated with placental infarction hematoma have not been reported. This paper describes a case of early and severe growth restriction with preeclampsia, and progressive deterioration of the fetal and placental Doppler parameters in the presence of a placental infarction hematoma. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Objective: To evaluate gestational age-dependent changes in the T2 relaxation time in normal murine placentas in vivo. The role of susceptibility-weighted imaging (SWI) in visualization of the murine fetal anatomy was also elucidated. Methods: Timed-pregnant CD-1 mice at gestational day (GD) 12 and GD17 underwent magnetic resonance imaging. Multi-echo spin echo and SWI data were acquired. The placental T2 values on GD12 and GD17 were quantified. To account for the influence of systemic maternal physiological factors on placental perfusion, maternal muscle was used as a reference for T2 normalization. A linear mixed-effects model was used to fit the normalized T2 values, and the significance of the coefficients was tested. Fetal SWI images were processed and reviewed for venous vasculature and skeletal structures. Results: The average placental T2 value decreased significantly on GD17 (40.17 ± 4.10 ms) compared to the value on GD12 (55.78 ± 8.13 ms). The difference in normalized T2 values also remained significant (p = 0.001). Using SWI, major fetal venous structures like the cardinal vein, the subcardinal vein, and the portal vein were visualized on GD12. In addition, fetal skeletal structures could also be discerned on GD17. Conclusion: The T2 value of a normal murine placenta decreases with advancing gestation. SWI provided clear visualization of the fetal venous vasculature and bony structures. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Mirror artifacts are produced by the reflection of ultrasound waves after they propagate through a structure and encounter a strong and smooth interface capable of acting as a mirror. Ultrasound waves bounce back and forth between the mirroring interface and the reflective object and then eventually return to the transducer. The typical display of the mirror artifact consists of two similar structures separated and at similar distances from the reflective interface. We report a mirror artifact in a patient with a singleton gestation at 18 weeks. The image was interpreted as consistent with a twin gestation using transabdominal and transvaginal ultrasound. The differential diagnosis consisted of an abdominal heterotopic pregnancy. The presence of synchronized but opposite movements of both fetuses, and the blurred image of the second fetus, suggested a mirror artifact. The reflective surface was created by the interface located between a distended rectosigmoid filled with gas and the posterior uterine wall. Mirror artifacts can lead to diagnostic errors. This case illustrates how a distended rectosigmoid colon can generate an image that simulates either a twin gestation or an abdominal heterotopic pregnancy. Copyright © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]