Bryann Bromley

The Genetic Sonogram A Method of Risk Assessment for Down Syndrome in the Second Trimester

Objective. To determine the risk of Down syndrome in fetuses with sonographic markers using the Bayes theorem and likelihood ratios. Methods. We prospectively evaluated the midtrimester sonographic features of fetuses with Down syndrome and compared them with euploid fetuses. Patients were referred for an increased risk of aneuploidy and evaluated for the presence of structural defects, a nuchal fold, short long bones, pyelectasis, an echogenic intracardiac focus, and hyperechoic bowel. All fetuses underwent amniocentesis at the time of sonographic assessment. The sensitivity, specificity, and likelihood ratios for markers were calculated both as nonisolated and isolated findings. Results. There were 164 fetuses with Down syndrome and 656 euploid fetuses. The presence of any marker resulted in sensitivity for the detection of Down syndrome of 80.5% with a false‐positive rate of 12.4%. The absence of any markers conferred a likelihood ratio of 0.2, decreasing the risk of Down syndrome by 80%. As an isolated marker, the nuchal fold had an “infinite” likelihood ratio for Down syndrome; a short humerus had a likelihood ratio of 5.8, whereas structural anomalies had a likelihood ratio of 3.3. Other isolated markers had low likelihood ratios because of the higher prevalence in the unaffected population. The likelihood ratios for the presence of 1, 2, and 3 of any of the markers were 1.9, 6.2, and 80, respectively. Conclusions. Although an isolated marker with a low likelihood ratio may not increase a patients risk of Down syndrome, the presence of such a marker precludes reducing the risk of aneuploidy. Clusters of markers appear to confer a higher risk.

Sonographic scoring index for prenatal detection of chromosomal abnormalities.

Current indications for cytogenetic evaluation leave the majority of Down syndrome fetuses undetected. Using advanced maternal age and low maternal serum alpha‐fetoprotein (AFP) levels as criteria, only 40% of fetuses with Down syndrome (trisomy 21) are identified (positive predictive value, 0.4% to 1%). We evaluate the sonographically detectable physical features of second trimester fetuses to determine whether these features are more sensitive and specific than maternal age for detecting fetuses with abnormal karyotypes. From March 1, 1990, to September 1, 1991, more than 5,000 fetuses between 14 and 20 weeks of development were referred for genetic amniocentesis because of advanced maternal age or abnormal AFP levels. Forty‐three of these 5,000 fetuses were later found to have autosomal trisomies by karyotype (32 with trisomy 21, nine with trisomy 18, and two with trisomy 13). A sample of 588 consecutive normal fetuses from the total of more than 5,000 amniocenteses performed during this period of time was used as our control group for statistical analysis. The sonographic features of these 588 normal second trimester fetuses and the 43 trisomic fetuses recorded prospectively prior to knowledge of the karyotype were evaluated statistically. The femur and humerus lengths, nuchal fold, renal pelvic dimension, and major structural defects were compared in the normal and trisomic fetuses. On the basis of our results, a weighted sonographic score was developed to optimize the detection of fetuses at risk for aneuploidy. Using our previously published formulas and criteria for a short femur and humerus, 17/32 (53%) fetuses with Down syndrome and 23/588 (3.9%) of the normal fetuses were identified. Twenty two of 32 Down syndrome fetuses (69%) and 2/588 (0.34%) of normals had a nuchal fold > or = 6 mm, and 11 of 32 Down syndrome fetuses and all those with trisomies 18 and 13 had a major anomaly detected sonographically. The following scoring system was developed for the detection of aneuploidy: nuchal fold = 2, major structural defect = 2, and short femur, short humerus, and pyelectasis = 1 each. Selecting fetuses with a score of > or = 2 would identify 26/32 (81%) Down syndrome fetuses, and 9/9 (100%) and 2/2 (100%) fetuses with trisomies 18 and 13 respectively, but only 26/588 (4.4%) of the normal fetuses. Using the sonographic score of 2 results in a positive predictive value for a 1/250 risk group of 6.87% for identifying Down syndrome fetuses and 7.25% for all three trisomies.(ABSTRACT TRUNCATED AT 400 WORDS)

Mild fetal lateral cerebral ventriculomegaly: Clinical course and outcome

The neonatal, pathologic outcome and karyotypic abnormalities are reported for 44 fetuses with mild ventriculomegaly diagnosed antenatally. Seventeen of these 44 fetuses (39%) had other ultrasonographic defects, and five (12%) had abnormal karyotypes. Five pregnancies were electively aborted and three other fetuses died in the neonatal period. Twenty-six (72%) of the remaining 36 live-born neonates are developmentally and clinically normal at 3 to 18 months of age. Twenty-one of these 26 had isolated mild ventriculomegaly as the only ultrasonographic finding. The other 10 live-born infants are developmentally impaired, and five of these 10 had mild ventriculomegaly as the only prenatal ultrasonographic abnormality. In conclusion, these data show that fetuses with mild ventriculomegaly have a lower incidence of associated anomalies and a better outcome than fetuses with more severe ventricular dilatation, as reported in the literature. The majority of fetuses with mild ventriculomegaly as an isolated finding and a normal karyotype are developing normally.

Echogenic intracardiac focus: A sonographic sign for fetal down syndrome

Objective To determine whether an echogenic intracardiac focus identified in the second-trimester fetus is related to an increased risk of Down syndrome. Methods During a 10-month period, all women with singleton gestations who underwent second-trimester genetic amniocentesis for non-imaging indications were evaluated prospectively by prenatal sonography. The presence or absence of an echogenic intracardiac focus was noted. Karyotypic information was obtained on each fetus. Results Among the 1334 patients in the study group, 66 fetuses (4.9%) had an echogenic intracardiac focus. Four of 22 fetuses (18%) with trisomy 21 had an echogenic intracardiac focus, compared with 62 (4.7%) of 1312 fetuses without Down syndrome who also had an echogenic intracardiac focus (P = .004). Sonographic identification of an echogenic intracardiac focus was associated with a fourfold increased risk of Down syndrome (risk ratio 4.3, 95% confidence interval 1.5–12.3). The overall prevalence of Down syndrome in our study population was 1.6%. The sensitivity, specificity, and positive predictive value for using the presence of an echogenic intracardiac focus to identify a fetus with Down syndrome was 18.2, 95.3, and 6.1%, respectively. Extrapolating to a lower risk population, the positive predictive value of an echogenic intracardiac focus for detecting Down syndrome in patients at an age-based risk of one in 250, one in 500, and one in 1000 was calculated to be 1.53, 0.77, and 0.39% respectively. Conclusions Fetuses with an echogenic intracardiac focus have a significantly increased risk of Down syndrome. Although most fetuses with this finding are normal, patients carrying fetuses with an echogenic intracardiac focus should be counseled about the increased risk of trisomy 21.

The sonographic diagnosis of Dandy-Walker and Dandy-Walker variant: associated findings and outcomes.

Outcomes of pregnancies with sonographically diagnosed Dandy–Walker (DW) or Dandy–Walker variant (DWV) syndromes vary widely. We examined our own experience with these diagnoses in an effort to identify those sonographic features that best predicted neonatal outcome. We identified 50 fetuses with DW and 49 with DWV diagnosed sonographically. Eighty‐six per cent of fetuses with DW and 85% of fetuses with DWV had other sonographically identifiable anomalies, the most common being ventriculomegaly (DW: 32%; DWV: 27%) and cardiac defects (DW:38%; DWV: 41%). Forty‐six per cent and 36% of available karyotypes in cases of DW and DWV, respectively, were abnormal. 50 out of 99 women in our series elected pregnancy termination. Only three pregnancies with DW resulted in a living infant, and only one of these had a normal paediatric examination at six‐week follow‐up. Thirteen out of 49 infants with DWV survived the neonatal period and 7 of 13 were reported initially as normal infants, including six with an isolated finding of DWV. We conclude that overall, the prognosis for these posterior fossa defects is grim but not uniformly fatal. The presence of other anomalies is associated with the worst prognosis. Isolated Dandy–Walker variant has the highest chance of leading to a normal neonate. Copyright

Adnexal masses during pregnancy: accuracy of sonographic diagnosis and outcome.

We sought to determine the accuracy of sonographic diagnosis and perinatal outcome in pregnancies with maternal adnexal masses. All patients with a prenatal sonographic diagnosis of an adnexal mass measuring 4 cm or greater beyond 12 weeks of gestation were identified. Only masses associated with live fetuses, for which pathologic follow‐up or direct visualization of the ovary was available at a single hospital, were included in the study. Sonographic evaluation of the pelvic mass was done prospectively at the time of the original scan and characterized on the basis of morphologic criteria. One hundred and twenty‐five pregnant patients 21 to 47 years old with 131 lesions formed the study group. The pathologic diagnoses included 40 dermoids, 15 endometriomas, 14 cysts, 13 cystadenomas, nine tubal cysts, four fibroids, and one ovarian cancer. Six patients had complex pathologic lesions and five had unusual diagnoses. Twenty‐four patients had normal ovaries on follow‐up examination. Sonographically benign appearing lesions were seen in 89.3% of patients. Ninety‐five percent of dermoids, 80% of endometriomas, and 71% of simple cysts were characterized correctly. Fourteen of the 131 lesions (10.7%) had sonographic characteristics suggestive of malignancy. One of these 14 patients (7%) had ovarian cancer. This represents a 0.8% malignancy rate among the total number of lesions. Twenty‐four of the 125 patients (19%) underwent second trimester laparotomy at the discretion of their managing obstetricians, with no pregnancy losses. One patient had acute torsion of a dermoid at 39 weeks. Prenatal sonography can accurately characterize maternal adnexal lesions.

Multidisciplinary consensus on the classification of prenatal and postnatal urinary tract dilation (UTD classification system)

OBJECTIVE Urinary tract (UT) dilation is sonographically identified in 1-2% of fetuses and reflects a spectrum of possible uropathies. There is significant variability in the clinical management of individuals with prenatal UT dilation that stems from a paucity of evidence-based information correlating the severity of prenatal UT dilation to postnatal urological pathologies. The lack of correlation between prenatal and postnatal US findings and final urologic diagnosis has been problematic, in large measure because of a lack of consensus and uniformity in defining and classifying UT dilation. Consequently, there is a need for a unified classification system with an accepted standard terminology for the diagnosis and management of prenatal and postnatal UT dilation. METHODS A consensus meeting was convened on March 14-15, 2014, in Linthicum, Maryland, USA to propose: 1) a unified description of UT dilation that could be applied both prenatally and postnatally; and 2) a standardized scheme for the perinatal evaluation of these patients based on sonographic criteria (i.e. the classification system). The participating societies included American College of Radiology, the American Institute of Ultrasound in Medicine, the American Society of Pediatric Nephrology, the Society for Fetal Urology, the Society for Maternal-Fetal Medicine, the Society for Pediatric Urology, the Society for Pediatric Radiology and the Society of Radiologists in Ultrasounds. RESULTS The recommendations proposed in this consensus statement are based on a detailed analysis of the current literature and expert opinion representing common clinical practice. The proposed UTD Classification System (and hence the severity of the UT dilation) is based on six categories in US findings: 1) anterior-posterior renal pelvic diameter (APRPD); 2) calyceal dilation; 3) renal parenchymal thickness; 4) renal parenchymal appearance; 5) bladder abnormalities; and 6) ureteral abnormalities. The classification system is stratified based on gestational age and whether the UT dilation is detected prenatally or postnatally. The panel also proposed a follow-up scheme based on the UTD classification. CONCLUSION The proposed grading classification system will require extensive evaluation to assess its utility in predicting clinical outcomes. Currently, the grading system is correlated with the risk of postnatal uropathies. Future research will help to further refine the classification system to one that correlates with other clinical outcomes such as the need for surgical intervention or renal function.

Significance of an Echogenic Intracardiac Focus in Fetuses at High and Low Risk for Aneuploidy

Our objective was to evaluate the significance of an echogenic intracardiac focus in a mixed population of fetuses at high and low risk for aneuploidy. Over a 1 year period, we prospectively identified all fetuses with an echogenic intracardiac focus seen during prenatal sonography. A detailed structural evaluation was performed on each fetus as permitted by gestational age. The location and number of foci were tabulated prospectively, as were associated abnormalities. Follow‐up was obtained by review of the medical record. Of the 290 fetuses who had an echogenic intracardiac focus, 14 of them were aneuploid (4.8%). Of the 290 mothers, 125 women were aged 35 years or older and 165 women were younger than 35 years old. Among the 125 fetuses born to women 35 years or older, eight were aneuploid fetuses (6.4%), while among the 165 fetuses of younger mothers, six were aneuploid fetuses (3.6%) (rate ratio = 1.8; 95% confidence interval [extremes] = 0.6, 4.9). Only one of the 14 aneuploid fetuses had an echogenic intracardiac focus as the only sonographic finding, and this occurred in a woman aged 41 years. The majority of the echogenic intracardiac foci (87.6%) were located in the left ventricle, while 4.8% of the foci were right‐sided and 7.6% were bilateral. Among the 14 aneuploid fetuses, 14% had bilateral echogenic intracardiac foci and 7% had right‐sided foci. Among the euploid fetuses, 7.3% had bilateral echogenic intracardiac foci and 4.7% had right‐sided foci. In conclusion, we have shown that the presence of an echogenic intracardiac focus does raise the risk that the fetus has a chromosomal abnormality, most commonly Down syndrome, although all but one aneuploid fetus in our study had other sonographic findings.

What does magnetic resonance imaging add to the prenatal sonographic diagnosis of ventriculomegaly

The purpose of this study was to determine the contribution of magnetic resonance imaging (MRI) in evaluating fetuses with the sonographic diagnosis of ventriculomegaly (VM).

How Sonographic Tomography Will Change the Face of Obstetric Sonography A Pilot Study

This study was undertaken to determine whether 3‐dimensional (3D) volume sonography (sonographic tomography) can yield a far quicker and equally accurate anatomic examination of the second‐trimester fetus compared with traditional 2‐dimensional (2D) scanning.