Enlarged Cavum Septi Pellucidi and Vergae in the Fetus: A Cause for Concern.

OBJECTIVES: To investigate fetal cases identified at our institution to determine whether an enlarged cavum septi pellucidi or cavum vergae is associated with other fetal abnormalities and whether its presence warrants more detailed investigation of the fetus. METHODS: In a retrospective study, 15 high- and low-risk patients undergoing prenatal sonography who had an enlarged cavum septi pellucidi or cavum vergae identified were reviewed. Data were collected for the sonographic study indication, gestation age at diagnosis of a prominent cavum, and associated anomalies. Follow-up outcome data regarding further imaging, karyotype, diagnosis of brain anomaly, and associated congenital abnormalities were obtained. RESULTS: Fifteen patients met the inclusion criteria. Nine patients were identified as having a prominent cavum septi pellucidi, and 6 were identified as having a prominent cavum vergae. The mean gestational age ± SD was 22.7 ± 5.9 weeks. Eleven patients made it to delivery. Of the 15 patients, 4 were thought to have trisomy 21, and 13 had congenital anomalies. Outcomes included 10 major adverse outcomes, 4 cases with normal development or minor abnormalities, and 1 lost to follow-up. An isolated dilated cavum on prenatal sonography was seen in 5 cases: 1 with lissencephaly on a neonatal examination, 3 premature deliveries (1 demise, 1 hospice, and 1 normal), and 1 unknown. CONCLUSIONS: Our cohort had many associated clinical anomalies: 3 confirmed trisomy 21 and 1 probable trisomy 21, 2 genetic disorders, and 10 major adverse outcomes, 5 of which were grave. Although we studied a small cohort, we conclude that an enlarged cavum septi pellucidi or cavum vergae warrants consideration of genetic counseling, which may include noninvasive prenatal testing (cell-free DNA), amniocentesis with microarray testing, or both.

Evaluation of Fetal First and Second Cervical Vertebrae: Normal or Abnormal?

OBJECTIVES: To use 3-dimensional sonographic volumes to evaluate the variable appearance of the normal fetal cervical spine and craniocervical junction, which if unrecognized may lead to misdiagnosis of malalignment at the first and second cervical vertebrae (C1 and C2). METHODS: Three-dimensional sonographic volumes of the fetal cervical spine were obtained from 24 fetuses at gestational ages between 12 weeks 6 days and 35 weeks 1 day. The volumes were reviewed on 4-dimensional software, and the vertebral level was determined by labeling the first rib-bearing vertebra as the first thoracic vertebra. The ossification centers of the cervical spine and occipital condyles were then labeled accordingly and evaluated for alignment and structure by rotating the volumes in oblique planes. The appearance on multiplanar images was assessed for possible perceived anomalies, including malalignment, particularly at the C1 and C2 levels. Evidence of head rotation was correlated with the presence of possible malalignment at C1-C2. Head rotation was identified in the axial plane by measuring the angle of the anteroposterior axis of C1 to the anteroposterior axis of C2. RESULTS: Of the 24 fetuses, 16 had adequate quality to assess the entire cervical spine and craniocervical junction. All 16 cases showed an osseous component of C1 that did not align directly with C2 on some of the multiplanar images when the volumes were rotated, which could lead to suspected diagnosis of spinal malalignment or a segmental abnormality, as occurred in 2 clinical cases in our practice. All 16 cases showed at least some degree of head rotation, ranging from 2° to 36°, which may possibly explain the apparent malalignment. The lateral offset from C1 to C2 ranged from 0.0 to 3.3 mm. CONCLUSIONS: The normal C1 and C2 ossification centers may appear to be malaligned due to normal offsetting (lateral displacement) of C1 on C2. An understanding of the normal development of the cervical spine is important in assessing spinal anatomy.

Placental Sonolucencies in the First Trimester: Incidence and Clinical Significance.

OBJECTIVES: The aims of this study were to determine the incidence of placental sonolucencies on first-trimester screening sonograms in a general obstetric population and assess whether these findings are associated with adverse obstetric outcomes. METHODS: A retrospective cohort analysis of 201 pregnant patients screened at a high-risk prenatal diagnostic center was conducted with first-trimester cine clips reviewed by 2 radiologists. Placental sonolucencies were defined as intraplacental anechoic or heterogeneous areas 0.7 cm or greater. Obstetric and neonatal outcomes were collected by chart review. RESULTS: Placental sonolucencies 0.7 cm or greater were seen in 45 (22.4%) of first-trimester ultrasound examinations. The ultrasonographic presence of a placenta previa, marginal sinus, and subchorionic hemorrhage was not more common in those with placental sonolucencies 0.7 cm or greater (P > 0.05). Sonolucencies were not associated with prior cesarean deliveries (P > 0.05). Both the groups with and without sonolucencies 0.7 cm or greater had similar rates of antepartum hemorrhage, preeclampsia, preterm delivery, cesarean delivery, postpartum hemorrhage, and delivery of small-for-gestational-age infants. One placenta accreta and no fetal demises occurred in the study population. CONCLUSIONS: Placental sonolucencies detected on first-trimester screening sonograms in the general obstetric population are not predictive of poor obstetric outcomes.

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.

Simplifying the ultrasound findings of the major fetal chromosomal aneuploidies.

Sonographic aneuploidy markers and structural anomalies associated with the 5 most common chromosomal aneuploidies are organized and simplified to highlight the many sonographic findings that are commonly seen with each aneuploidy. Identification of these findings allows families to have the option to pursue prenatal genetic testing to confirm or exclude chromosomal abnormalities suggested by such prenatal ultrasound findings and make informed decisions about the subsequent management of their pregnancy. We review the most common major human chromosomal aneuploidies, including trisomies 21, 18, and 13; Turner syndrome; and triploidy. The focus is on the major structural anomalies seen with each of these, as well as ultrasound markers (findings associated with increased risk of chromosomal abnormality but also seen in normal fetuses). The role of clinical information such as maternal serum screening and new cell-free fetal DNA screening is also reviewed. As patients do not usually present for fetal ultrasound with a known diagnosis, a concise knowledge of ultrasound and clinical findings will alert radiologists to concerning cases and prompt a guided search for important associated anomalies. Fetal ultrasound can be challenging owing to the many findings and sometimes technically difficult evaluation. By simplifying the ultrasound findings seen with the major chromosomal abnormalities and highlighting the role of clinical history, we hope that an informed search for specific sonographic findings can be performed; thereby, reducing missed diagnoses.

Prenatally diagnosed fetal split-hand/foot malformations often accompany a spectrum of anomalies.

The purpose of this series was to identify cases that appeared on sonography to be split-hand/foot malformations (SHFMs) in fetuses and correlate the sonographic findings, including 2-dimensional (2D) and 3-dimensional (3D) sonography, to outcomes. A retrospective review was conducted of sonographic studies from 2002 to 2012 at 2 fetal care centers. Data were collected with respect to the morphologic characteristics of split-hand/foot abnormalities, the utility of 3D sonography, associated anatomic abnormalities, family histories, gestational ages at diagnosis, fetal outcomes, karyotype, and autopsy results. Ten cases were identified with gestational ages ranging from 15 to 29 weeks. Three-dimensional sonography was helpful in defining anatomy in 7 of 9 cases in which it was performed. Bilateral SHFMs were found in 7 cases (3 cases involving both hands and feet, 2 cases isolated to hands, and 2 cases isolated to feet), whereas 3 cases showed unilateral split-hand malformations. Associated anatomic anomalies were present in 6 cases, and 4 of these had recognized syndromes, including 2 with abnormal karyotypes, specifically, del(22q11) and del(7q31). Two cases occurred in the context of a positive family history of SHFM. Three cases were delivered at term, and 7 cases were electively terminated. In conclusion, SHFMs often occur with a broad range of chromosomal abnormalities, single-gene disorders, and other congenital anomalies. Some apparent SHFMs turn out to be other limb anomalies, such as complex syndactyly. Prenatal screening using 2D sonography can identify SHFMs, and 3D sonography often further clarifies them.

Cystic lymphangioma of the lesser curvature of the stomach--case report.

We report a case of a cystic lymphangioma arising from the lesser curvature of the stomach in a 16-year-old female who initially presented with abdominal pain, nausea, and emesis. Contrast enhanced computed tomography and magnetic resonance imaging revealed a large, thin-walled multicystic mass located anteromedial to the stomach, which was predominately supplied by the left gastric artery. Given the imaging appearance and location, a mesenteric cyst, specifically a cystic lymphangioma, was considered. Lymphangioma was the final pathological diagnosis after laparotomy with complete resection of the cystic abdominal mass.

Spectral Doppler signature waveforms in ultrasonography: a review of normal and abnormal waveforms.

Doppler ultrasound is routinely used in the clinical setting to evaluate blood flow in many major vessels of the body. Spectral Doppler is used to display the normal and abnormal signature waveforms that are unique to each vessel. It is important for the sonographer and the radiologist to recognize both what is normal and what is abnormal in a spectral Doppler display. In this review, we briefly explain the physics behind Doppler ultrasound and some of the most common mathematical equations applied in a routine clinical examination. We also describe and demonstrate normal versus abnormal spectral Doppler signature waveforms of vessels in the neck, abdomen, pelvis, and fetus.

Evaluation of the fetal secondary palate by 3-dimensional ultrasonography.

OBJECTIVE: Diagnosis of cleft lip and palate remains a challenge with 2-dimensional ultrasonography, particularly when clefting involves only the secondary palate. The utility of 3-dimensional ultrasonography (3DUS) has enhanced our ability to detect clefts. We report our experience with a modification of the flipped face technique to aid in the diagnosis of clefting of the secondary palate. METHODS: Ninety-two volumes of 92 fetal faces were evaluated. Thirty-six volumes were acquired prospectively. Fifty-six volumes had previously been acquired and included 8 with clefting of the secondary palate. Volumes were obtained on 3DUS systems and reviewed by 4 blinded readers on personal computer workstations. Volumes were manipulated so that an upright profile was visualized. The palate was then rendered using a thin, curved render box. Statistical analysis was performed using the Fisher exact test for categorical data. Intraclass correlations were computed to assess inter-rater agreement. RESULTS: The mean gestational age at image acquisition +/- SD was 22 +/- 5 weeks. Image quality of the secondary palate was obtained and rated as adequate by at least 2 reviewers in 34% (31 of 92) of volumes. The sensitivity of cleft detection ranged from 33% to 63%, and the specificity ranged from 84% to 95%. The low sensitivity was mainly due to artifacts/shadowing. The inter-rater reliability was 0.62 (95% confidence interval, 0.47-0.76). CONCLUSIONS: Three-dimensional ultrasonography can be used to diagnose clefts of the secondary palate. This evaluation is limited by the fetal position and artifacts from shadowing of adjoining structures. Pseudoclefts can be created, and optimal imaging cannot be obtained in all fetuses.

Three-dimensional ultrasonographic depiction of fetal abdominal blood vessels.

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Diagnostic evaluation of the fetal face using 3-dimensional ultrasound.

Evaluation of the fetal face with 3-dimensional ultrasound allows for evaluation of the fetal face using surface rendering, multiplanar and multislice displays. Three-dimensional ultrasound offers many benefits in evaluating the fetal face because it can be rotated into a standard symmetrical orientation and reviewed millimeters by millimeters by scrolling through the volumes. New rendering tools now allow imaging of the hard palate. Clinical applications where 3-dimensional ultrasound adds value as an adjunct to 2-dimensional ultrasound imaging that are reviewed in this paper include cleft lip and palate, micrognathia and other profile abnormalities, metopic suture abnormalities, presence and absence of the nasal bones, orbit abnormalities, and ear abnormalities. In addition, the literature regarding parental bonding to the fetus after viewing 3-dimensional images of their fetuses is reviewed.

Three-dimensional obstetric ultrasound.

Three-dimensional ultrasound has gained a significant popularity in obstetrical practice in recent years. The advantage of this modality in some cases is in question, however. This article provides a basic review of volume acquisition, mechanical positioning, and display modalities. Multiple uses of this technique in obstetrical care including first trimester applications and its utility in clarification of fetal anatomy such as brain, face, heart, and skeleton is discussed.