Image Correlation Volume Data Sets Research Articles

Reference Intervals of Fetal Cardiac Volume Between 14 and 40 Weeks of Gestation.

To construct the reference intervals for the cardiac volume (CV) of normal fetuses between 14 and 40 weeks of pregnancy. Low risk singleton pregnancies with normal fetuses were prospectively recruited to acquire 4D-cardio-spatiotemporal image correlation volume datasets (VDS). Subsequent off-line analyses of VDS were anonymously performed to calculate CV using the Virtual Organ Computer-aided AnaLysis technique. The reference intervals were established as a function of gestational age (GA), biparietal diameter (BPD), head circumference (HC), and estimated fetal weight (EFW) based on the best-fitted models for both mean and standard deviation (SD). A total of 668 VDS were successfully calculated for CV. The best-fitted models for the means and SDs are as follow: 1) GA in week=6.422 + e(-100.653 × GA) (SD=0.641 - (0.170 × GA) + (0.009 × GA2 )). 2) BPD=0.016 × (BPD)3.589 (SD=2.663 - (1.410 × BPD) + (0.224 × BPD2 )). 3) HC=0.00017 × (HC)3.537 (SD=2.341 - (0.341 × HC) + (0.015 × HC2 )). The CV progressively increased with advancing fetal age (GA) and size (BPD, HC). The reference intervals of CV, theoretically best representing cardiac size, in relation to GA, BPD, HC, and EFW were first established and Z-score was readily calculated. These will be helpful in detection of cardiac abnormalities, especially those associated with cardiomegaly.

Semiautomatic Fetal Intelligent Navigation Echocardiography Has the Potential to Aid Cardiac Evaluations Even in Less Experienced Hands.

To investigate the interobserver and intraobserver variability and corresponding learning curve in a semiautomatic approach for a standardized assessment of the fetal heart (fetal intelligent navigation echocardiography [FINE]). A total of 30 stored spatiotemporal image correlation volume data sets of second-trimester fetuses were evaluated by 3 physicians with different levels of expertise in fetal echocardiography by using the FINE approach. Data were analyzed regarding the examination time and proper reconstruction of the diagnostic cardiac planes. The completions and numbers of correct depictions of all diagnostic planes were evaluated by a blinded expert (time t0). To determine interobserver and intraobserver variability, the volumes were reassessed after a 4-week training interval (time t1). All operators were able to perform the investigation on all 30 volumes. At t0, the interobserver variability between the beginner and both the advanced (P = .0013) and expert (P < .0001) examiners was high. Focusing on intraobserver variability at t1, the beginner showed a marked improvement (P = .0087), whereas in advanced and expert hands, no further improvement regarding proper achievement of all diagnostic planes could be noticed (P > .999; P = .8383). The beginner also showed improvement in the mean investigation time (t0, 82.8 seconds; t1, 73.4 seconds; P = .0895); nevertheless, the advanced and expert examiners were faster in completing the examination (t1, advanced, 20.9 seconds; expert, 28.3 seconds; each P < .0001). Based on our results, the FINE technique is a reliable and easily learned method. The use of this semiautomatic work flow-based approach supports evaluation of the fetal heart in a standardized and time-saving manner. A semiautomatic evaluation of the fetal heart might be useful in facilitating the detection of fetal cardiac anomalies.

Assessment of cardiac angle in fetuses with congenital heart disease at risk of 22q11.2 deletion.

To evaluate fetal cardiac angle as a screening tool for 22q11.2 deletion among cases with cardiac anomalies known to be associated with this genetic condition, to examine the correlation of fetal cardiac angle with thymic-thoracic (TT)-ratio, and to assess the performance of TT ratio as a covariate in screening for 22q11.2 deletion. This was a retrospective cohort study that reviewed the records of 74 cases with cardiac anomalies known to be associated with 22q11.2 deletion (tetralogy of Fallot, common arterial trunk, interrupted aortic arch and right aortic arch) that were diagnosed between 2007 and 2013. The karyotype was known in all cases. The fetal cardiac angle and TT-ratio were measured using stored three-dimensional spatiotemporal image correlation volume datasets and compared in those with del.22q11.2 and those without. Of the 74 cases reviewed, 16 had 22q11.2 deletion. The mean cardiac angle was larger in the cases with 22q11.2 deletion than in those without (68.6° vs 58.7°, respectively; P = 0.02). Multivariate regression analysis showed an association between cardiac angle and TT-ratio in fetuses with 22q11.2 deletion (r(2) = 0.33; P = 0.02) but not in those with a normal karyotype (P = 0.4). Logistic regression analysis demonstrated that fetal cardiac angle, but not TT-ratio, is an independent predictor of 22q11.2 deletion among fetuses with 22q11.2 deletion-associated cardiac anomalies (P = 0.02; area under the receiver-operating characteristics curve = 0.69). An enlarged fetal cardiac angle is an independent predictor of 22q11.2 deletion among fetuses with 22q11.2 deletion-associated cardiac anomalies. However, its performance as a single variable in a screening model is not sufficient to guide management decisions regarding invasive testing.

Sonocubic fine: new three-dimensional ultrasound software to the screening of congenital heart diseases.

Congenital heart disease is the most common fetal congenital malformations; however, the prenatal rate detection still is low. The two-dimensional echocardiography is the "gold standard" exam to screening and diagnosis of congenital heart disease during the prenatal; however, this exam is operator-depending and it is realized only in high risk pregnancies. Spatio-temporal image correlation is a three-dimensional ultrasound software that analyses the fetal heart and your connections in the multiplanar and rendering modes; however, spatio-temporal image correlation too is operator-depending and time-consuming. We presenting a new three-dimensional software named Sonocubic fine to the screening of congenital heart disease. This software applies intelligent navigation technology to spatio-temporal image correlation volume datasets to automatically generate nine fetal echocardiography standard views. Thus, this new software tends to be less operator-depending and time-consuming.

Comparison of Fetal Cardiac Spatiotemporal Image Correlation Segmental Analysis Between Cardiac‐ and Body‐Based Scrolling

The purpose of this study was to compare success rates for depiction of the 5 typical transverse planes in the fetal upper thorax between cardiac- and body-based scrolling techniques. Spatiotemporal image correlation volume data sets acquired at the 4-chamber view level were obtained from low-risk singleton pregnancies with healthy fetuses. Each data set was analyzed by the authors using both cardiac- and body-based techniques. With the cardiac-based technique, the exact 4-chamber view was first identified as an initial plane before scrolling, whereas with the body-based technique, a volume data set was first manipulated to get the fetal orientation in the exact dorsal supine position as an initial plane. In both techniques, the volumes were then scrolled through the upper thorax to identify the standard planes, including the 4-chamber, 5-chamber, 3-vessel, 3-vessel and trachea, and aortic arch views. An analysis of 50 volume data sets to evaluate intraobserver and interobserver variability in the success rates for the 4-chamber, 5-chamber, 3-vessel, 3-vessel and trachea, and aortic arch views showed good agreement. In an analysis of 296 separate data sets, cardiac-based scrolling was associated with significantly higher success rates than body-based scrolling in all standard planes (P < .05). Cardiac-based scrolling resulted in higher success rates for obtaining the standard spatiotemporal image correlation planes than body-based scrolling. Therefore, examiners in the early part of the learning curve should be encouraged to first identify a perfect 4-chamber view at the start of an examination.

Reference Ranges for Fetal Septum Primum Excursion From 14 to 40 Weeks' Gestation

The purpose of this study was to establish reference ranges for septum primum excursion and the septum primum excursion index. Normal singleton pregnancies with certain dates from 14 to 40 weeks' gestation were enrolled to acquire spatiotemporal image correlation volume data sets. The stored data sets were subsequently displayed offline to measure septum primum excursion and the left atrium diameter. The measured values were regressed to identify the best-fitted model as a function of gestational age and biparietal diameter. A total of 624 volumes were successfully measured, and normal reference ranges for predicting means and standard deviations of septum primum excursion and the septum primum excursion index were established based on best-fitted equations. The septum primum excursion index was relatively constant throughout pregnancy (mean ± SD, 0.474 ± 0.082), whereas septum primum excursion increased with gestational age and biparietal diameter as follows: (1) septum primum excursion = -6.30 + 0.667 × gestational age - 0.009 × gestational age(2); SD of septum primum excursion = 0.219 + 0.02 × gestational age; and (2) septum primum excursion = -3.342 + 1.933 × biparietal diameter - 0.102 × biparietal diameter(2); SD of septum primum excursion = 0.330 + 0.065 × biparietal diameter. Percentile charts for predicting septum primum excursion and equations for Z score calculation were also provided. Normal reference ranges for fetal septum primum excursion and the septum primum excursion index have been provided. These normative data may be useful tools for assessment of hemodynamics through the foramen ovale or left ventricular diastolic function.

Fetal Cardiac Circumference Derived by Spatiotemporal Image Correlation as a Predictor of Fetal Hemoglobin Bart Disease at Midpregnancy

The purpose of this study was to evaluate the efficacy of the fetal cardiac circumference derived by spatiotemporal image correlation (STIC) for predicting fetal hemoglobin (Hb) Bart disease. Pregnancies at risk of fetal Hb Bart disease at 17 to 22 weeks' gestation were enrolled. All underwent STIC volume acquisition for analysis of fetal cardiac dimensions and cordocentesis for Hb level and Hb typing analysis. Spatiotemporal image correlation volume data sets were subsequently analyzed offline for cardiac circumference measurements, which were used to evaluate the efficacy in predicting fetal anemia and fetal Hb Bart disease. A total of 88 pregnancies at risk of fetal Hb Bart disease at 17 to 22 weeks were recruited into the study. The cardiac circumference was significantly higher in fetuses with Hb Bart disease than in unaffected fetuses (1.33 and 1.02 multiples of the median [MoM], respectively; P < .001). The cardiac circumference effectively predicted fetal Hb Bart disease (area under the receiver operating characteristic curve, 0.85; 95% confidence interval [CI], 0.73-0.97), with sensitivity of 86.4% (95% CI, 72.0%-100%) and specificity of 78.1% (95% CI, 68.0%-88.3%) using a cutoff point of greater than 1.17 MoM, whereas the cardiothoracic ratio had better efficacy, with sensitivity of 90.9% (95% CI, 78.9%-100%) and specificity of 85.9% (95% CI, 77.4%-94.5%) using a cutoff point of greater than 0.50. At midpregnancy, a cardiac circumference of greater than 1.17 MoM can be used as an alternative sonographic marker for predicting fetal Hb Bart disease, although not perfectly. However, the cardiothoracic ratio seems to be more accurate than the cardiac circumference for such a purpose.

Fetal Aortic Arch Measurements at 14 to 40 Weeks' Gestation Derived by Spatiotemporal Image Correlation Volume Data Sets

The purpose of this study was to establish reference ranges for the transverse aortic arch diameter (TAD) and distal aortic isthmus diameter (DAID) in normal singleton pregnancies (14-40 weeks) based on the 3-vessel/trachea (3VT) view of cardio-spatiotemporal image correlation (STIC) volume data sets. A prospective descriptive study was conducted on uncomplicated singleton pregnancies with healthy fetuses and an accurate gestational age (GA). Cardio-STIC examinations were performed by experienced sonographers using a high-resolution ultrasound machine, and the volume data sets were manipulated to obtain the 3VT view and measured for the TAD and DAID. A total of 554 measurements were performed, ranging from 13 to 30 for each gestational week. The best regression models were as follows: TAD (in millimeters) = -1.01 + 1.69 (GA, in weeks) (r(2) = 0.93; P < .001), and DAID (in millimeters) = -0.85 + 1.54 (GA, in weeks) (r(2) = 0.92; P < .001). A table of nomograms for 5th, 50th, and 95th percentile ranges was constructed. Normative data for the TAD and DAID at each gestational week from 14 to 40 weeks were constructed by a new technique of measurement based on cardio-STIC. These reference ranges may be useful tools for assessment of fetal aortic arch abnormalities.

Tomographic Ultrasound Imaging of the Fetal Heart

In 2003 and 2004, the American College of Radiology, the American Institute of Ultrasound in Medicine, and the American College of Obstetricians and Gynecologists published guidelines for the standard ultrasound examination of the fetus. Each group recommended that the outflow tracts of the fetal heart be examined if technically feasible. One method to accomplish this task is to perform a free-hand sweep of the transducer beam directed in a transverse plane from the 4-chamber view to the fetal neck. One problem with this approach is that the examiner may not direct the beam transversely and, therefore, may not accurately identify the outflow tract anatomy. A new technology, tomographic ultrasound imaging (TUI), allows the examiner to obtain a volume data set that simultaneously displays multiple images at specific distances from the 4-chamber view. This study examined TUI technology for identifying normal and abnormal fetal cardiac anatomy with the use of either static or spatiotemporal image correlation volume data sets. The 4 views used in the screening examination of the outflow tracts of the fetal heart (4-chamber, 5-chamber, 3-vessel, and tracheal views) could be identified with the use of TUI technology in fetuses between 13 and 40 weeks' gestation. Examples of fetuses with abnormal cardiac anatomy of the outflow tracts (tetralogy of Fallot, transposition of the great vessels, and pulmonary stenosis) all showed abnormal anatomy on TUI. Tomographic ultrasound imaging technology enables the fetal examiner to evaluate the 4-chamber view and the outflow tracts in a systematic manner to identify normal and abnormal cardiac anatomy.