B-flow Imaging Research Articles

Evaluation of normal fetal pulmonary veins using B‐flow imaging with spatiotemporal image correlation and by traditional color Doppler echocardiography

The purpose of our report is to evaluate the use of color Doppler echocardiography (CDE) with four chamber view (4CV), scanning around left atrium, and four-dimensional echocardiography with B-flow imaging and spatiotemporal image correlation (4D BF-STIC) in detecting fetal pulmonary veins at 17 to 40 weeks' gestation. This was a prospective study. Color Doppler echocardiography with 4CV, scanning around left atrium, and 4D BF-STIC were used to detect the pulmonary veins in 460 normal fetuses at 17 to 40 weeks of gestation. Routine prenatal screening was used to confirm that the fetuses were in good health with no cardiac or extra cardiac anomalies. All patients underwent follow up at one year. Twenty-two patients were excluded from the study. The number of pulmonary veins visualized using each method was recorded and then compared in six subgroups according to gestational age. Four-dimensional echocardiography with B-flow imaging and spatiotemporal image correlation was the best method to detect the greatest number of pulmonary veins between 17 and 31 weeks of gestation. Scanning around left atrium detected more pulmonary veins than the traditional 4CV method throughout the gestational period. The scanning around left atrium method proved to be the most suited for detecting pulmonary veins in clinical practice. 4D BF-STIC was superior in detecting the greatest number of pulmonary veins before 32 gestational weeks, but had limited clinical usage because it was very time-consuming and experience-dependent. The 4D method should be considered as a complement to traditional two-dimensional sonography, because it facilitates understanding of the anatomy and the spatial relationships of the cardiac structures.

Relationship between the detection of carotid plaque's micro flow signals by B-flow imaging and acute cerebral infarction

Objective To detect the micro flow signals of carotid plaque by ultrasound B-flow imaging (BFI) and elucidate its relationship with acute cerebral infarction.Methods A total of 63 patients with carotid plaques were divided into 2 groups.acute cerebral infarction (ACI,n =48) and control (n =15).BFI was used to detect the micro flow signals of plaques and comparisons were made with the categorizing results of contrast enhanced ultrasound (CEU).The data were analyzed between two methods.Results The micro flow signals were detected in 15.7％ (22/140)patients in the ACI group vs.2.3％(1/44) in the control group.There were more signals in hypoechoic plaques.The detection percentage of micro flow in grade Ⅲ was significantly higher than that in grades Ⅰ and Ⅱ with CEU (P =0.005,P =0.027).No significant differences existed between grades Ⅲ and Ⅳ (P =1.000).Conclusion BFI can detect effectively the micro flow signals of carotid plaques and this characteristic is correlated with the symptoms of ACI. Key words: Ultrasonography; Cerebrovascular accident; Atherosclerosis

High frame rate velocity-coded speckle imaging platform for coherent blood flow visualization

Non-invasive imaging of blood flow at over 100 fps (i.e. beyond video display range) is known to be of clinical interest given that such a high frame rate is essential for coherent visualization of complex hemodynamic events like flow turbulence. From a technical standpoint, getting into this frame rate range has became possible with the advent of broad-view ultrasound imaging paradigms that can track motion over an entire field-of-view using few pulse-echo firings. Leveraging on an imaging paradigm known as plane wave excitation, a novel high-frame-rate flow visualization technique has been developed to depict both blood speckle motion (using B-flow imaging principles) and flow velocities (using conventional color flow imaging principles). Experimental demonstration of this method has been carried out using a channel-domain research platform that supports real-time pre-beamformed data acquisition (SonixDAQ) and a high-throughput processing engine that is based upon graphical processing unit technology (d...

Novel Application of Four-Dimensional Sonography with B-Flow Imaging and Spatiotemporal Image Correlation in the Assessment of Fetal Congenital Heart Defects

To evaluate the role of four-dimensional (4D) ultrasound with B-flow imaging and spatiotemporal image correlation (STIC) in the evaluation of normal fetal heart and congenital heart disease during pregnancy. Volume data sets of the fetal heart were acquired with automated transverse and longitudinal sweeps of the anterior chest wall. We studied 31 normal fetuses and 28 fetuses with congenital heart disease (6 with double-outlet right ventricle, 5 with complete transposition of great arteries, 8 with tetralogy of Fallot, 3 with right aortic arch, 2 with persistent left superior vena cava, 3 with truncus arteriosus communis, and 1 with interruption of aortic arch) at gestation ages ranging from 18 to 39 weeks using transabdominal 4D B-flow sonography with STIC (4D BF-STIC). Four-dimensional BF-STIC demonstrated dynamic angiographic features in both normal and abnormal fetal hearts. Four-dimensional BF-STIC images could not be obtained in two normal fetuses at 18.9 and 35.6 weeks because of the high fetal heart rate and inappropriate fetal position. Of the other 29 fetuses all extracardiac vessels such as aorta, pulmonary artery, ductus arteriosus, inferior vena cava, and ductus venosus could be detected on reconstructed images. In seven normal cases, a 4D image was recorded to allow simultaneous visualization of all four pulmonary veins. In the 28 fetuses with cardiac anomalies, 4D sonography with B-flow imaging and STIC detected the "digital casts" of the outflow tracts, great arteries, and veins draining into the heart. These results demonstrate spatial relationship among these structures which provide important anatomical information. Four-dimensional BF-STIC provides a means of real time three-dimensional evaluation of fetal extracardiac hemodynamics in the second and third trimesters. This novel technique assists in the evaluation of fetal cardiac hemodynamics and may play an important role in future fetal cardiac research and in the identification of anatomical features of different congenital cardiac anomalies.

Multi-channel pre-beamformed data acquisition system for research on advanced ultrasound imaging methods

The lack of open access to the pre-beamformed data of an ultrasound scanner has limited the research of novel imaging methods to a few privileged laboratories. To address this need, we have developed a pre-beamformed data acquisition (DAQ) system that can collect data over 128 array elements in parallel from the Ultrasonix series of research-purpose ultrasound scanners. Our DAQ system comprises three system-level blocks: 1) a connector board that interfaces with the array probe and the scanner through a probe connector port; 2) a main board that triggers DAQ and controls data transfer to a computer; and 3) four receiver boards that are each responsible for acquiring 32 channels of digitized raw data and storing them to the on-board memory. This system can acquire pre-beamformed data with 12-bit resolution when using a 40-MHz sampling rate. It houses a 16 GB RAM buffer that is sufficient to store 128 channels of pre-beamformed data for 8000 to 25 000 transmit firings, depending on imaging depth; corresponding to nearly a 2-s period in typical imaging setups. Following the acquisition, the data can be transferred through a USB 2.0 link to a computer for offline processing and analysis. To evaluate the feasibility of using the DAQ system for advanced imaging research, two proof-of-concept investigations have been conducted on beamforming and plane-wave B-flow imaging. Results show that adaptive beamforming algorithms such as the minimum variance approach can generate sharper images of a wire cross-section whose diameter is equal to the imaging wavelength (150 μm in our example). Also, planewave B-flow imaging can provide more consistent visualization of blood speckle movement given the higher temporal resolution of this imaging approach (2500 fps in our example).

Transoral Carotid Ultrasonography Using A Micro Convex Probe with B-flow Imaging for Extracranial Internal Carotid Artery Dissection

We report on transoral carotid ultrasonography using a micro convex probe with B-flow imaging for determining spontaneous extracranial internal carotid artery dissection just below the petrous portion. A 49-year-old man suffered cortical and subcortical infarction in the region of the right middle cerebral artery. Magnetic resonance angiography on the third day of admission revealed spontaneous recanalization of the right internal carotid artery associated with an intimal flap-like structure at the petrous portion. Transoral carotid ultrasonography using a micro convex probe revealed right extracranial internal carotid artery dissection, showing an increased diameter of the right extracranial internal carotid artery with double lumen formation, stenosis of the true lumen, and a mobile intimal flap in B-flow imaging. Transoral carotid ultrasonography using a micro convex probe was helpful to attempt a self-expanding stent for recanalizing right extracranial internal carotid artery dissection. The patient recovered and was discharged ambulatory. The size of the micro convex probe was optimum for transoral carotid ultrasonography in our patient. Micro convex probe is more commonly used than the standard transoral carotid ultrasonography probe, which lacks versatility. We consider that transoral carotid ultrasonography using a micro convex probe could be routinely used for ultrasonographic evaluation of extracranial internal carotid artery dissection.

B‐flow imaging for the measurement of residual lumen diameter of renal artery stenosis

The aim of this study was to assess the accuracy and efficacy of B-flow imaging (BFI) in the diagnosis and measurement of renal artery stenosis (RAS) compared with color duplex ultrasonography (CDU) and digital subtraction angiography (DSA). Fifty-one consecutive patients with RAS diagnosed and measured with DSA were subsequently and independently examined with BFI for the measurement of residual lumen diameter, and with CDU for the measurement of peak systolic velocity and renal-aortic velocity ratio. The diagnostic performances of BFI and CDU in determining 60-99% RAS were compared by receiver operating characteristic curve analysis. The agreement between DSA and BFI stenosis measurements was evaluated with Bland-Altman method. The area under curve was 0.983 for BFI and 0.959 for CDU, without a significant difference in diagnostic performances (p = 0.26). BFI yielded an 88% sensitivity and 94% specificity in the diagnosis of RAS with a 3% underestimation of RAS compared to DSA (95% confidence interval 1.4%, 4.6%). BFI is an accurate method that minimally underestimates RAS. It might provide an additional benefit to CDU in patients with RAS.

A case of spontaneous dissection of the left internal carotid artery diagnosed using a microconvex probe with B-flow imaging

A case of spontaneous dissection of the left internal carotid artery diagnosed using a microconvex probe with B-flow imaging

Four‐dimensional echocardiography with B‐flow imaging and spatiotemporal image correlation in the assessment of congenital heart defects

The objective of the present study was to evaluate the role of four-dimensional ultrasound with B-flow imaging and spatiotemporal image correlation (STIC) in the detection of congenital heart defects. Automated longitudinal and transverse sweeping of the fetal chest was utilized to obtain the volume datasets of the heart. Among the fetuses recruited in the study, 20 were normal and 13 were fetuses with congenital heart anomalies. Reconstructed images of abnormal hearts were compared with those of normal fetuses. Of the 20 normal fetuses, all extracardiac vessels such as aorta, pulmonary artery, ductus artery, inferior vena cava, and ductus venosus could be detected on reconstructed images of 16 fetuses. In five normal cases, a four-dimensional image was recorded to allow simultaneous visualization of all four pulmonary veins. In the 13 fetuses with cardiac anomalies, four-dimensional sonography with B-flow imaging and STIC detected the 'digital casts' of the outflow tracts, great arteries, and veins draining into the heart. These results demonstrate spatial relationship among these structures which provide important anatomical information. The use of four-dimensional ultrasound examination with B-flow imaging and STIC is a very useful technique in identifying anatomical features of different congenital cardiac anomalies.

Fetal interrupted aortic arch: 2D‐4D echocardiography, associations and outcome

To analyze fetal two-dimensional (2D) echocardiographic characteristics of interrupted aortic arch (IAA) and its different types, to explore whether the use of 4D ultrasound with B-flow imaging and spatiotemporal image correlation (STIC) can improve prenatal diagnostic accuracy, and to describe associations and outcome. The study comprised IAA fetuses examined exclusively by 2D conventional echocardiography during the period from 1994 to 2003, and those identified by conventional echocardiography and examined further by 4D ultrasound with B-flow imaging and STIC during the period January 2004 to July 2008, identified among fetuses examined at two referral centers for congenital heart defects (CHD). Postnatal follow-up was available in all cases. Karyotyping and fluorescent in-situ hybridization (FISH) analysis for the DiGeorge critical region (22q11.2) were performed in all cases. Twenty-two cases of isolated IAA (15 Type B and seven Type A, seven and three of which, respectively, underwent B-flow imaging and STIC) were detected among 2520 cases of fetal CHD. In seven of the 15 Type B cases, a right subclavian artery arose anomalously (ARSA). 2D echocardiography failed to distinguish the type of IAA in only two cases and the ARSA in five of the seven cases. B-flow imaging and STIC successfully identified IAA types in all 10 cases examined and clearly visualized the origin and course of the ARSA, including cervical ones. FISH detected 22q11.2 microdeletion in 10 of the 15 Type B cases and an unusual association with Type A in one of the seven cases. Fetal/neonatal outcome included: eight terminations of pregnancy, one intrauterine death and four postoperative deaths in the neonatal period, and nine neonates were alive after surgery at a mean follow-up time of 58 months (range, 4 months-13 years). Our results confirm the feasibility of prenatal characterization of IAA and its different types based on 2D echocardiographic examination, albeit with some limitations in the thorough assessment. 4D ultrasound with B-flow imaging and STIC can apparently facilitate visualization and detailed examination of the anatomical features of the IAA types, including visualization of the neck vessels, thus supplying additional information with respect to 2D sonography. As for the known association with microdeletion 22q11.2, our data indicate that Types A and B are distinct, there being a close association only with IAA Type B.

B-flow and color Doppler sonography findings in iatrogenic carotid–jugular arteriovenous fistula

We describe the case of a 66-year-old woman with an aortic valve reconstruction. Subsequently she presented with an arteriovenous fistula (AVF) between the left common carotid artery and internal jugular vein following several attempts of jugular catheter insertion. Due to aliasing, correct visualization of the fistula track was hindered by conventional color Doppler. However, by using the B-flow imaging technique, the fistula track could be detected without aliasing or overwriting. Duplex examination revealed an AVF between both vessels with an arterialized waveform in the left jugular vein and a high-velocity turbulent flow inside the fistula. Due to these findings we will change our routine scanning protocol for extracranial vessels and will use B-flow in indistinctive or difficult conditions to obtain additional informations.

The ‘starfish’ sign: a novel sonographic finding with B‐flow imaging and spatiotemporal image correlation in a fetus with total anomalous pulmonary venous return

Total anomalous pulmonary venous return (TAPVR) is a serious congenital anomaly that can lead to delivery of a critically ill newborn if not recognized during fetal life.1,2 Volpe et al.3 have described the inclusion of B-flow imaging using spatiotemporal image correlation (STIC) for fetuses with total anomalous pulmonary venous connection. We now wish to report another affected fetus that extends these original observations and further demonstrates the value of this methodology for detailed anatomic evaluation of complex congenital heart disease. A 19-year-old woman, gravida 1 para 0, was referred to our unit at 21 weeks’ gestation for an abnormal cardiac screening examination that included left cardiac axis deviation, ventricular septal defect (VSD), and a single overriding arterial outflow tract. In addition to her clinical examination, she agreed to participate in an imaging research protocol that was approved by the institutional review boards of William Beaumont Hospital and the Eunice Kennedy Shriver National Institute of Child Health and Human Development. Volume ultrasonography (Voluson E8, GE Healthcare, Milwaukee, WI, USA) demonstrated the following: (1) right-sided aortic arch; (2) large perimembranous VSD with overriding aorta; (3) pulmonary atresia; (4) large aortopulmonary collateral artery arising anteriorly from the descending aorta; and (5) poorly visualized pulmonary veins into the left atrium. Our differential diagnosis included tetralogy of Fallot with pulmonary atresia and truncus arteriosus. Anomalous pulmonary venous return was also considered because of the poorly visualized pulmonary veins into the left atrium. Four-dimensional ultrasonography with B-flow and STIC imaging were later used to demonstrate a confluence of pulmonary veins that drained into a vertical vein behind the left atrium, resembling a starfish in shape (Figure 1, Videoclip S1). Figure 1 4D ultrasonography, using B-flow imaging and spatiotemporal image correlation, demonstrating tetralogy of Fallot, pulmonary atresia and total anomalous venous return, from a left oblique view of the posterior heart. A confluence of pulmonary veins drains ... Amniocentesis results revealed an apparently unrelated partial duplication of the short arm of chromosome 16 (16p11.2 to 16p12), but not a 22q minus chromosomal anomaly. A male infant was delivered at term gestation. Neonatal echocardiography confirmed tetralogy of Fallot with pulmonary valve atresia, levocardia, and a right aortic arch. Situs solitus was noted without evidence of isomerism. An aortopulmonary collateral vessel ultimately supplied both pulmonary arteries and the ductus arteriosus was absent. Four pulmonary veins drained into a vertical vein that emptied into a left innominate vein. This vessel subsequently coursed beneath the aortic arch into a right superior vena cava. Postnatal surgery on day 3 included placement of a conduit that connected the right ventricle to the pulmonary artery, perimembranous VSD closure, and correction to total anomalous venous return. The infant had failure to thrive with persistent chylous pleural drainage and eventually expired at 5 months of age. B-flow technology digitally enhances signals from weak blood reflectors from vessels and, at the same time, suppresses strong signals from surrounding tissues.4 The method does not rely on Doppler ultrasonography to display blood flow, is angle-independent, and permits relatively high frame rates with excellent spatial resolution. This approach may be advantageous over color or power Doppler imaging when used in conjunction with STIC for the evaluation of fetal vasculature. Our findings extend those in the original case series of Volpe et al. of fetuses with TAPVR using B-flow imaging and STIC.3 This image demonstrates an unusual degree of anatomic detail for this complicated anomaly and now documents a starfish-like appearance of confluent pulmonary veins as a supracardiac form of TAPVR. In our experience, most prenatal cases of congenital heart disease can be adequately visualized using conventional 2D ultrasonography. Some complex heart anomalies, however, can be further characterized from the additional use of volume sonography with B-flow imaging.

Prenatal Diagnosis of Coarctation of the Aorta With the Multiplanar Display and B-Flow Imaging Using 4-Dimensional Sonography

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Three‐Dimensional Ultrasonographic Depiction of Fetal Abdominal Blood Vessels

The purpose of this study was to identify fetal abdominal vasculature with 3-dimensional (3D) ultrasonography and to describe a systematic method for analysis of volume data sets. Three-dimensional volumes of the fetal abdomen were acquired prospectively in 30 patients between 15 and 34 weeks' gestation with color Doppler, high-definition (HD) flow, power Doppler, and B-flow imaging. All volumes were analyzed offline by 2 examiners separately. The feasibility of identifying the fetal abdominal blood vessels was analyzed. A standardized approach was applied to identify specific vessels by correlating the images with known anatomic landmarks. The volumes were rotated into an anatomic orientation in the multiplanar mode, and then the vessels were identified in the following order: aorta (30 of 30), celiac trunk (29 of 30), superior mesenteric vein (28 of 30 and 26 of 30 for readers 1 and 2, respectively), superior mesenteric artery (29 of 30), left renal artery (25 of 30 and 26 of 30), right renal artery (27 of 30), common iliac arteries (30 of 30), umbilical arteries (26 of 27), external iliac arteries (20 of 22), umbilical vein (29 of 30), ductus venosus (30 of 30), hepatic vein (29 of 30), right portal vein (29 of 30), inferior vena cava (28 of 30), adrenal artery (2 of 30), hepatic artery (24 of 30 and 23 of 30), splenic artery (24 of 30 and 23 of 30), gastric artery (14 of 30 and 9 of 30), splenic vein (19 of 30 and 15 of 30), and renal vein (1 of 30). A step-by-step systematic approach to identify the abdominal vasculature from the ultrasonographic volume data set was developed. Fetal abdominal vessels can be easily visualized when a systematic analysis is performed on 3D data set volumes. Visualization of the vessels was optimal when volumes were acquired with HD flow imaging.

1535: Usefulness of B-Flow Imaging in Carotid Artery Ultrasound Examination

1535: Usefulness of B-Flow Imaging in Carotid Artery Ultrasound Examination

Quantitative Morphometry of Carotid Artery Stenosis: B-Flow Ultrasound Imaging Determines Longer Stenosis-Lengths Compared to Computer-Defined Obstruction Analysis of Angiograms

Quantitative Morphometry of Carotid Artery Stenosis: B-Flow Ultrasound Imaging Determines Longer Stenosis-Lengths Compared to Computer-Defined Obstruction Analysis of Angiograms

Contrast-enhanced ultrasound imaging of periadventitial vasa vasorum in human carotid arteries

Arterial vasa vasorum (VV) are known to be involved in the atherosclerotic process. The aim of the present study was to explore whether ultrasound imaging with contrast agent is able to visualize adventitial VV in human carotid atherosclerosis. We studied with standard ultrasound 25 patients with carotid stenosis >50% (ATS group) and 15 patients without carotid artery plaques and an intima-media thickness (IMT) <1.0 mm (CTRL group). All patients underwent contrast ultrasound to evaluate periadventitial VV and B-flow imaging (BFI) modality was used to improve and measure periadventitial flow signal. On contrast-enhanced images, a fast microbubble flow and a homogeneous and linear periadventitial contrast signal using BFI were detectable in the adventitial area in all patients of both groups. Periadventitial signal thickness by BFI was higher in patients with atherosclerosis than in the control group (mean +/- SD: CTRL 0.80+/-0.06 mm; ATS 1.10+/-0.11 mm; P<0.001). Moreover, considering the whole study population, the adventitial signal thickness significantly correlated with IMT values (r=0.88, r(2)=0.77; P<0.0001). Periadventitial contrast signal was detected in all patients and BFI thickness was higher in patient with carotid atherosclerosis and correlated with IMT.

A New Marker for Diagnosis of Thyroid Papillary Cancer

The purpose of this study was to correlate the presence and patterns of distribution of B-flow imaging (BFI) twinkling signs within thyroid nodules with the histologic evidence of microcalcifications and the results of the sonographically guided fine-needle aspiration to establish their role in predicting the risk of malignancy. Between September 2006 and December 2007, 343 consecutive patients with 479 suspected nodules (maximum diameter > 9 mm) were enrolled in this prospective study. Sonographic and BFI examinations were performed with a commercially available real-time sonography system, and all patients also underwent a cytologic evaluation. Written informed consent was obtained from all patients. Patients with suspicious or malignant cytologic features underwent surgery. On histologic examination, 66 of 479 nodules were malignant (59 papillary thyroid carcinoma, 1 Hürthle cell carcinoma, and 6 follicular carcinoma). All sonographic characteristics, which were potential predictors of thyroid malignancy (microcalcifications, hypoechogenicity, absence of a halo, and a predominantly solid composition), were found in different percentages in both histologically verified malignant and benign nodules. For BFI, pattern 3 (> or = 4 signs and distance > 2 mm) was the most predictive factor for malignancy (specificity, 99.6%; sensitivity, 65.2%), whereas pattern 2 (> or = 4 signs and distance < 2 mm) was a positive factor because it was detected only in benign lesions, with a positive predictive of 0. Our results indicate that BFI can overcome the limits of the traditional B-mode and color Doppler sonographic features in the diagnosis of thyroid nodules. This technique provides maximum specificity levels both in the case of benign nodules with pattern 2 and in the case of malignant nodules with pattern 3.

Thyroid B-flow twinkling sign: a new feature of papillary cancer

BackgroundMicrocalcifications (aggregated with psammoma bodies), detected by ultrasound (US), are the most specific feature of papillary thyroid cancer (PTC). Using B-flow imaging (BFI), we identified a new sign (the twinkling sign; BFI-TS) in ‘suspect’ PTC nodules, which appeared to be generated by microcalcifications.ObjectiveTo evaluate whether the BFI-TS was predictive of malignancy, we correlated the BFI-TS with the results of fine needle aspiration cytology and histology.DesignCross-sectional cohort study from September 2006 to April 2008.SettingDepartment of Radiology and Endocrinology, University of Naples Federico II, and Department of Endocrinology, Second University of Naples.PatientsA total of 306 consecutive patients with 539 thyroid nodules >8 mm in diameter.Main outcome measureUS and BFI examinations were performed with the Logiq 9 system (General Electric Company, Milan, Italy); all patients underwent cytological examination.ResultsCytology revealed 455 (84.4%) benign nodules and 84 (15.6%) malignant nodules; the latter were confirmed by postsurgical histological examination (76 cases of PTC, 7 follicular carcinoma, and 1 Hürthle cell carcinoma). All suspect nodules, namely, nodules with potential predictors of thyroid malignancy (e.g., microcalcifications and intra-nodal vascularity), were analyzed by cytology or histology (or both). Of 84, 68 (80.9%) of malignant nodules had ≥4 or more BFI-TSs in at least one scan versus only 12 of 455 (2.6%) of benign lesions.ConclusionsOur results indicate that the BFI-TS could be a reliable diagnostic technique in the management of suspect thyroid nodules.

Four‐dimensional sonography with B‐flow imaging and spatiotemporal image correlation for visualization of the fetal heart

To use B-flow imaging with 4-dimensional (4D) sonography and spatiotemporal image correlation (STIC) in the evaluation of normal fetal heart and congenital heart disease during pregnancy. Volume data sets of the fetal heart were acquired with automated transverse and longitudinal sweeps of the anterior chest wall. We studied 13 normal fetuses and 2 fetuses with congenital heart disease (1 double-outlet right ventricle and 1 hypoplastic left heart syndrome) at gestation ages ranging from 13 to 39 weeks using transabdominal 4D B-flow sonography with STIC (4D BF-STIC). 4D BF-STIC demonstrated dynamic angiographic features in both normal and abnormal fetal hearts. 4D BF-STIC images could not be obtained in 2 normal fetuses at 18.1 and 33.1 weeks because of the high fetal heart rate and inappropriate fetal position. In normal fetal heart, characteristic hemodynamic changes in both atria and ventricles were clearly demonstrated in systole and diastole. 4D BF-STIC also allowed visualization of the relationship, size, and course of the outflow tracts, thus helping the examiner to better understand the relationships between the vessels. In a case of hypoplastic left heart syndrome, dramatic hemodynamic changes including the right atrium, right ventricle, and pulmonary artery were evident. In a case of double-outlet right ventricle with ventricular septal defect, left-to-right shunt flow through a ventricular septal defect was clearly shown, as were great arteries originating in parallel from the right ventricle. 4D BF-STIC provides a means of real-time 3-dimensional evaluation of fetal intracardiac and extracardiac hemodynamics in the second and third trimesters. This novel technique assists in the evaluation of fetal cardiac hemodynamics and may play an important role in future fetal cardiac research and in the evaluation of congenital heart disease in the fetus.