What Are the Double Lines of the Fetal Cavum Septi Pellucidi on Ultrasound?

OBJECTIVE: To demonstrate the significance of the double line appearance of the septi pellucidi laminae (SPL) on fetal ultrasound. METHOD: A total of 522 uncomplicated singleton pregnancies (15 to 39 weeks' gestational age) with fetal ultrasounds were enrolled. The presence of a single versus double line SP as well as measurement of the cavum septi pellucidi (CSP) was determined retrospectively. Ultrasound settings from the CSP images were recorded. Thickness of the SPL was measured in 20 ultrasound and 14 MRI cases; histology was reviewed from one neonate. Maternal BMI and gestational age were also recorded. RESULTS: The presence of double line SPL is a normal sonographic finding, seen in 47% (188/403) of normal fetuses. Thickness of the SPL in 10 cases with double line averaged 1.4 mm and in 10 cases with single line averaged 0.8 mm; MRI measurements were within 0.1 mm of the corresponding ultrasound measurements. Double line cavum was more often seen with mid-dynamic contrast range settings (5, 6) rather than high range settings (7-10) (P value <.05). The double line was only visualized on ultrasound when the angle of insonation was at or near perpendicular to the laminae; it was never visualized on coronal ultrasound imaging or MRI imaging. CONCLUSION: A double line septum pellucidum lamina is a normal finding seen in almost 50% of uncomplicated singleton pregnancies. It may be attributed to borders of cell layers within each lamina that form separate specular reflections on both sides; this can be accentuated by ultrasound settings and beam angulation.

The Fetal 3-Vessel Views: An Illustrative Case-Based Tutorial.

In 2018, the American Institute of Ultrasound in Medicine revised its obstetric Practice Parameter for the second-trimester fetal anatomic survey. The 2018 Practice Parameter recommends incorporation of the 3-vessel view and 3-vessel and trachea view "if technically feasible." Sonographers and other medical providers may require additional training and education to develop greater proficiency in obtaining and interpreting these views. This pictorial essay, including ultrasound images alongside their respective schematic diagrams, provides an up-to-date, practical, and clinically oriented review of the 3-vessel view and 3-vessel and trachea view and their most common presentations in the context of congenital heart disease.

Timing and Mode of Delivery in Prenatally Diagnosed Congenital Heart Disease- an Analysis of Practices within the University of California Fetal Consortium (UCfC).

Prenatal diagnosis of critical congenital heart disease (CHD) is associated with decreased morbidity. It is also associated with lower birth weights and earlier gestational age at delivery. The University of California Fetal Consortium (UCfC) comprises five tertiary medical centers, and was created to define treatment practices. We utilized this consortium to assess delivery patterns and outcomes in subjects with prenatal and postnatal diagnosis of CHD. A retrospective cohort study was conducted on maternal-neonatal pairs diagnosed with complex CHD prenatally (n = 186) and postnatally (n = 110) from 2011 to 2013. Outcomes were assessed between groups after adjusting for disease severity. Prenatally diagnosed subjects were born earlier (38.1 ± 0.11 vs. 39 ± 0.14 weeks, p = < 0.001), and had lower birth weights (2853 ± 49 vs. 3074 ± 58 g, p = 0.005) as compared to postnatal diagnosis. For every week increase in gestational age and 100 g increase in birth weight, length of stay decreased by 12.3 ± 2.7% (p < 0.001) and 3.9 ± 0.9% (p < 0.001). Subjects with prenatal diagnosis were more often born via cesarean both planned (35.6 vs. 26.2%, p = 0.004) and after a trial of labor (13 vs. 7.8%, p = 0.017). Neonates with cesarean delivery trended toward a longer length of stay (2.6 days longer), and were born earlier as compared to other modalities (37.7 ± 0.22 weeks, p = 0.001). Management after prenatal diagnosis of CHD appears to have modifiable disadvantages for maternal and neonatal outcomes. The UCfC provides a platform to study best practices and standardization of care for future studies.

Anomalous Pulmonary Venous Return: Insights Into Prenatal Detection.

OBJECTIVES: To review all cases of total anomalous pulmonary venous return (TAPVR) or partial anomalous pulmonary venous return (PAPVR) identified prenatally or postnatally at a single institution and to identify factors that may lead to a correct or missed diagnosis in both high- and low-risk fetuses on screening examinations. METHODS: Fetal images from 16 cases of prenatally or postnatally diagnosed T/PAPVR were retrospectively reviewed to analyze factors that influenced interpretations and diagnoses. RESULTS: Sixteen diagnoses of T/PAPVR were made, with a final number of 10 confirmed cases, 1 of which was PAPVR. Ten fetuses with a presumptive diagnosis of T/PAPVR before delivery were at an average gestational age of 24.7 weeks, with 5 cases diagnosed postnatally. None of the diagnoses of isolated TAPVR were made during a screening examination. Twelve of the pregnancies were complicated by complex cardiac defects, including 6 with heterotaxy syndromes. Of the 5 abnormal cases identified in the postpartum period, 3 had isolated TAPVR. In the 3 patients with isolated defects, prenatal echocardiography was not performed; the anatomy scan interpretations were confounded by multiple factors. In retrospect, there was no obvious sonographic evidence of TAPVR in these patients; however, color flow Doppler imaging of the pulmonary veins was not performed on any of them. CONCLUSIONS: Although fetal echocardiography has improved the overall detection of TAPVR or PAPVR, this abnormality continues to elude prenatal diagnosis during screening in both low- and high-risk patients. We hypothesize that the use of color flow Doppler imaging in the 4-chamber view may assist in diagnosing TAPVR in screening low-risk patients, especially in those with difficult scans.

Congenital cardiac anomalies: prenatal readings versus neonatal outcomes.

OBJECTIVE: The purpose of this study was to determine the variation between prenatal and postnatal diagnosis of congenital cardiac lesions diagnosed by both fetal center primary physicians and fetal pediatric cardiologists at a single tertiary referral center in the United States and evaluate why cases were misdiagnosed. METHODS: A retrospective review of all cardiac abnormalities identified prenatally by level II sonography at a tertiary referral fetal center between January 2006 and December 2008 was performed to include any patient with a fetal cardiac abnormality and with a documented autopsy or neonatal follow-up. Congenital heart disease diagnoses were classified as correct, incorrect, or incorrect but within the same spectrum of disease. Cases of correct diagnosis by primary physicians and pediatric cardiologists were compared. RESULTS: Sixty patients with fetal heart abnormalities were identified among 8894 patients who had level II sonography. The combined detection rate for fetal heart abnormalities for both primary physicians and pediatric cardiologists together was 81.7%. The detection rates of congenital heart disease were not statistically different between primary physicians and pediatric cardiologists: 77.9% (46 of 59) versus 85.0% (34 of 40; P = .3). The most common cardiac abnormalities misdiagnosed in our study population included pulmonic stenosis, ventricular septal defect, myxoma, truncus arteriosus, and coarctation of the aorta. CONCLUSIONS: Congenital heart disease is misdiagnosed in tertiary care centers by both pediatric cardiologists and fetal imaging specialists. We believe that this occurrence is related to multiple factors, including evolution of congenital heart disease, maternal body habitus, associated congenital anomalies, decreased amniotic fluid volume, gestational age at evaluation, imaging techniques, and, most importantly, the experience of the sonographer.

Detailed Fetal Anatomic Ultrasound Examination: Effect of the 2014 Consensus Report on a Tertiary Referral Center.

This study evaluates the impact of extended cardiac views on examination time, repeat imaging, and anomaly detection before and after implementation of 76811 guidelines (American Institute of Ultrasound in Medicine Consensus 2014). It is a retrospective study of singleton pregnancies undergoing detailed ultrasound imaging at 18 weeks' gestation or greater before and after the protocol change in an academic, tertiary care fetal center. Views required prior to 2014: 4-chamber, left outflow tract, right outflow tract. Additional views required after 2014: bicaval, aortic arch, 3-vessel, and 3-vessel trachea. Fetuses with known anomalies were excluded. Rates of detection of congenital heart disease (CHD), examination completion, repeat examination recommendation, fetal echocardiogram recommendation, completion by body mass index, and cardiac examination time were determined. Six hundred twenty-four subjects were included, 217 before and 407 after protocol change. Views obtained were as stated in the American Institute of Ultrasound in Medicine/Society for Maternal-Fetal Medicine consensus. Detection of CHD was not improved. Examination times increased by 20% (6.4 vs 7.7 minutes, P < 0.05). Number of incomplete studies increased by 130% (11% to 26%, P < 0.05). Twice as many patients were referred for repeat examination (6% vs 13%, P < 0.05). Completion rates were negatively correlated with body mass index. Recommendations for fetal echocardiogram were unchanged (5% vs 6%, P = 0.6). Additional imaging did not increase detection rate of CHD (3% vs 2%, P = 0.3). Extended cardiac views resulted in increased examination time, more incomplete examinations, and more repeat examinations without changing detection rates of CHD.

Setting up a Nuchal Translucency Clinic: What Radiologists Need to Know.

The purpose of this article was to discuss the process of setting up a nuchal translucency (NT) screening clinic in clinical practice, how to interpret the information in combination with other clinical tests, what to do if abnormal results are obtained, and to illustrate some of the fetal anomalies that are associated with an increased NT. The NT was initially implemented to predict the likelihood of a fetus with Down syndrome. Maternal age can be combined with fetal NT and maternal serum biochemistry (free ß-hCG and PAPP-A) at 11 to 14 weeks to identify about 90% of affected fetuses. Setting up a clinic to perform the NT screening requires certified physicians and certified sonographers. Certification can be obtained for both physicians and sonographers through Nuchal Translucency Quality Review and Fetal Medicine Foundation. Cell-free DNA testing is now altering what our patients are choosing to evaluate fetuses at risk for chromosomal anomalies and congenital anomalies. Common pitfalls to performing, interpreting, and conveying results of the NT are illustrated in this article. Nasal bone measurement, fetal anatomy examination and fetal echocardiography are tools that add sensitivity to the detection of chromosomal abnormalities. Examples of fetal anomalies discovered during the NT screening are also illustrated. Screening for obstetric complications is an additional benefit to the NT clinic.