Visualization Of Fetal Anatomy Research Articles

How to avoid errors when computing reference interval tables and graphs using regression equations for cross-sectional studies of fetal biometry.

While visualization of fetal anatomy is one of the primary purposes of diagnostic ultrasound, the application of statistical analysis to biological measurements of fetal structures such as the head, abdomen, long bones, and heart, requires equations that compute changes in these measurements over time. One of the challenges for the investigator who desires to compute reference intervals for a fetal measurement is selecting the best equation for the measurements of interest. Fractional polynomial regression equations have been used to describe changes in fetal measurements over time and consists of 44 equations for the investigator to select. Since it would be laborious to analyze each equation to identify the best fit of the data, software programs have been developed for such analysis. However, depending upon the software program, potential errors can occur when translating the coefficients of a complex equation to a format that can be used by the clinician to create reference interval tables and graphs. This study reviews the requirements for statistical output that allows the investigator to generate reference interval tables and graphs using Excel. A step-by-step sequence is explained that enables the investigator to minimize the possibility of errors when reporting complex equations and their associated graphs that result from fractional polynomial regression analysis. Using the techniques described in this opinion paper should decrease the potential for reporting erroneous equations used to compute reference interval tables and graphs. This article is protected by copyright. All rights reserved.

Maternal Superobesity and Visualization of Fetal Anatomy [A344

INTRODUCTION: Obesity rates continue to increase in reproductive age women. It is well described that obesity impairs adequate image acquisition on sonographic fetal anatomic survey. However, there are limited data regarding rates of anatomic survey completion in women with superobesity (BMI≥50). We sought to investigate adequacy of fetal anatomic visualization in women with superobesity. METHODS: Retrospective chart review of women with singleton nonanomalous pregnancies presenting for fetal anatomic survey from 18 0/7 to 21 6/7 weeks’ gestation between January 1, 2019 and December 30, 2020. The primary outcome was rate of total anatomic survey completion stratified by BMI category. Secondary outcomes were scan duration, number of images, and complete visualization of grouped organ systems. Results were analyzed using Chi-square and Kruskal Wallis tests where appropriate. RESULTS: Of 2,719 ultrasounds, 9% of patients were normal weight, 31% overweight, 55% obese, and 5% superobese. Rates of anatomic survey completion were highest in normal-weight women, and lowest in women with superobesity (67.6% vs. 4.4%, P<.001). When grouped by organ system, superobesity impacted all organ system completion rates, with cardiac structures the most affected (75% vs. 8%, P<.001). The median exam duration and number of images decreased with increasing BMI category (range 33.5-28.4 minutes and 86-63 images, respectively). CONCLUSION: Women with weight classifying as superobese had extremely low rates of completed anatomic survey on first attempt. Examination duration and number of images were lower for superobese patients, which may represent sonographer assessment of futility. This has important implications for anomaly detection and resource utilization.

Virtual navigation for the improvement of parents counseling and the planning of fetal endoscopic myelomeningocele repair

Myelomeningocele (MMC) is the most severe form of spina bifida with intrauterine repairs becoming more prevalent. The development of three-dimensional ultrasound (3DUS) and magnetic resonance imaging (MRI) has drastically improved the visualization of fetal anatomy. Virtual Navigation (VN) results from a technology that uses software generated realistic images to replicate the immersive feeling of a real environment. This report aims to demonstrate VN in a Chiari II malformation case, obtained from 3DUS and MRI files, comparing this with the fetal endoscopic surgery for MMC.

Multicentric studies of the fetal neurobehavior by KANET test.

Assessment of fetal neurobehavior and detection of neurological impairment prenatally has been a great challenge in perinatal medicine. The evolution of four-dimensional (4D) ultrasound not only enabled a better visualization of fetal anatomy but also allowed the study of fetal behavior in real time. Kurjak Antenatal Neurodevelopmental Test (KANET) was developed for the assessment of fetal neurobehavior and the detection of neurological disorders, based on the assessment of the fetus by application of 4D ultrasound in the same way that a neonate is assessed postnatally. KANET is a method that has been applied for the past 10 years and studies show that it is a strong diagnostic tool and can be introduced into everyday clinical practice. We present all data from studies performed up to now on KANET.

First Trimester Ultrasound in Prenatal Diagnosis-Part of the Turning Pyramid of Prenatal Care.

First-trimester sonographic assessment of the risk of chromosomal abnormalities is routinely performed throughout the world, primarily by measuring fetal nuchal translucency thickness between 11–13 weeks’ gestation, combined with assessment of serum markers. The development of high-frequency transvaginal transducers has led to improved ultrasound resolution and better visualization of fetal anatomy during the first-trimester. Continuous improvement in ultrasound technology allows a thorough detailed assessment of fetal anatomy at the time of the nuchal translucency study. Using transabdominal or transvaginal sonography, or a combination of both approaches, it is now possible to diagnose a wide range of fetal anomalies during the first trimester. Multiple studies reported early diagnosis of major fetal anomalies after demonstrating the association of increased nuchal translucency thickness with structural defect in chromosomally normal and abnormal fetuses. Normal sonographic findings provide reassurance for women at high risk while detection of fetal malformation during the first trimester enables discussion and decisions about possible treatments and interventions, including termination of pregnancy, during an early stage of pregnancy.

Limitations of the fetal anatomic survey via ultrasound in the obese obstetrical population

Objective: To evaluate limitations of the fetal anatomic survey in obese women. Methods: Retrospective cohort study of obese gravidas with singleton gestations who had at least one, sonographic fetal evaluation at ≥14 weeks between January 2009 and March 2011. The impact of pre-pregnancy body mass index (BMI), placental location, prior cesarean scar and sonographer experience on ability to achieve an adequate ultrasound was evaluated using multilevel modeling. Ability to visualize specific fetal parts by BMI class and gestational age was also evaluated. Results: There were 245 obese women (42% with class III obesity). Senior faculty (>20 years experience) were more likely to achieve adequate visualization (adjusted odds ratio [aOR] 3.27; 95% confidence interval [CI] 1.15–9.25) compared with junior faculty. Among women with BMI > 40.0, odds of inadequate views of the face and spine were 10.0 (95% CI 1.31–76.0) and 5.17 (95% CI 0.65–40.8), when compared with women with a BMI = 30–34.9. Odds for inadequate views of sex (OR 3.83; 95% CI 0.86–17.1) and extremities (OR 4.37; 95% CI 0.99–19.4) were similarly increased with a BMI ≥ 40. The optimal gestational age for a complete anatomic survey was 22–24 weeks (93% completion rate), with an OR of 41.3 (95% CI 7.89–215.8), compared with a survey at 14–16 weeks. Conclusions: Attending sonographer experience is associated with improved visualization of fetal anatomy among obese gravidas. Face, spine, sex and extremity views are particularly difficult in the highest BMI category.

Three-dimensional Ultrasound in the Visualization of Fetal Anatomy in the Three Trimesters of Pregnancy

Three-dimensional Ultrasound in the Visualization of Fetal Anatomy in the Three Trimesters of Pregnancy

Fetal behavior in multifetal pregnancies studied by four-dimensional sonography

Rapid improvements in the capacity of data processing due to technological breakthroughs in processor engineering is the basis of spatial imaging. Spatial imaging is the main benefit of three-dimensional sonography and it is used for visualization of fetal anatomy in three dimensions. Modern machines are capable of performing spatial imaging in near real time, called four-dimensional sonography. Four-dimensional sonography in multifetal pregnancies can be used for detection and evaluation of intertwin contacts, because it allows simultaneous visualization of both fetuses and assessment of their motor activity. The main benefits of four-dimensional sonography include: accurate recognition of an isolated motor activity of a single fetus; distinguishing between spontaneous and stimulated motor activity; and spatial visualization of the intertwin area.

Sonographers and sonologists hold favorable views of the role of three‐dimensional ultrasound (3DUS) in obstetrics following a formal lecture on the subject

Purpose: To assess awareness and attitudes towards the use of 3DUS in obstetrics in a group of medical professionals attending a national imaging conference.Methods: Around 200 subjects attended a 45‐min lecture on 3DUS and obstetrics at a major national meeting. The lecture included slides and multimedia content. Eighty‐eight individuals (68 female and 20 male) completed a self‐administered questionnaire regarding their impressions of the subject following the talk.Results: No subject had personally undergone 3DUS, however, 78% of women said that they would like to have a 3DUS in a future pregnancy. Sixty‐five percent of men said they would encourage their partner to have a 3DUS in a future pregnancy. Of those who favored 3DUS in a future pregnancy, 54% cited better visualization of fetal anatomy as their main reason for this choice, 12% felt that 3DUS afforded advantages over 2DUS in anomaly detection. Only 5% felt that 3DUS would be more reassuring than 2DUS to them personally. Despite this, 80% of all subjects felt that 3DUS would have a major role in reassurance for lay women carrying a normal fetus in the future. Seventy‐two felt that 3DUS should be more widely available for prenatal diagnosis than at present. 3DUS was felt to offer advantages over 2DUS for anomaly detection by 38% of subjects. The multiplanar capability of 3DUS, production of ‘realistic images’ and ready recognition of fetal structures were cited as reasons for this view.Conclusion: 3DUS used in an obstetric setting appears to have already gained significant levels of acceptance amongst this audience of imaging professionals. Most believe that 3DUS should be more widely available for the evaluation of both normal and abnormal fetuses. The value of 3DUS in the production of readily understandable images of a normal fetus in the reassurance of pregnant women was widely endorsed.