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Ray O Bahado-Singh

Publications and source records attributed to Ray O Bahado-Singh.

10 recordsLinked to original sources
PubMed2005

Elevated first-trimester nuchal translucency increases the risk of congenital heart defects.

OBJECTIVE: We sought to evaluate the association between first trimester nuchal translucency measurement and the risk for major congenital heart defect in chromosomally normal fetuses. STUDY DESIGN: First trimester (10 weeks 4 days of gestation to 13 weeks 6 days of gestation) nuchal translucency was obtained in a large prospective multicenter National Institute of Child Health and Human Development study for Down syndrome prediction. The study, which was conducted between May 1998 and December 2000, was restricted to singleton pregnancies. Gestational age was determined by crown rump length measurements. Perinatal outcomes were determined and included the frequency of major congenital heart defect, which was defined as those cases that potentially could require surgery, intensive medical therapy, or prolonged follow-up time. Logistic regression analysis was used to determine whether nuchal translucency was a significant predictor of congenital heart defect. RESULTS: There were 8167 chromosomally normal pregnancies, of which 21 cases of major congenital heart defect were identified at follow-up examination (incidence, 2.6/1000 pregnancies). The risk of congenital heart defect rose with increasing nuchal translucency measurements. The mean nuchal translucency value for the normal and congenital heart defect groups were 1.5 mm and 1.9 mm, respectively (P = .05). With a nuchal translucency measurement of < 2.0 mm, the incidence of congenital heart defect was 13 of 6757 pregnancies (1.9 of every 1000 pregnancies). At 2.0 to 2.4 mm, the incidence was 5 of 1032 pregnancies (4.8 of every 1000 pregnancies). At 2.5 to 3.4 mm, the incidence was 2 of 335 pregnancies (6.0 of every 1000 pregnancies). At > or = 3.5 mm, the incidence was 1 of 43 pregnancies (23 of every 1000 pregnancies). Logistic regression analysis confirmed that nuchal translucency was associated significantly with congenital heart defect (odds ratio, 2.1; 95% CI, 1.4-3.1; P = .0004). CONCLUSION: Increased first trimester nuchal translucency measurement was associated with a higher risk of major congenital heart defect in chromosomally normal pregnancies. The practical implications of our findings are that patients with unexplained elevations of nuchal translucency may need referral for a fetal echocardiogram.

Adult↗
PubMed2005

The mid-trimester genetic sonogram.

The genetic sonogram is a composite algorithm combining multiple individual markers to increase Down syndrome risk prediction. Transformation of sonographic information into a standard mathematical format represented an early challenge that has now been surmounted. Using increasingly sophisticated mathematical techniques, individual patient risk can be estimated. High diagnostic accuracy comparable to standard mid-trimester serum algorithms has been reported. Most recently, a few studies have reported the ability to combine serum and biochemical markers to achieve diagnostic accuracy comparable to first-trimester screen. Even fewer studies have reported combinations of ultrasound and maternal urine markers. While it is clear that consistently high sensitivity and specificity for Down syndrome can be achieved, almost all the studies are based on high-risk groups. Studies in low-risk populations have suffered from lack of standardization. The relevance of genetic sonogram in a low-risk population thus remains to be proven. The most significant challenge, however, remains the development of uniform and reproducible sonographic and measurement standards. This is likely to be the most important factor in optimizing the accuracy of the mid-trimester genetic sonogram.

Down Syndrome↗
PubMed2004

First- and midtrimester Down syndrome screening and detection.

Overall, Down syndrome detection capabilities have improved remarkably over the last 2 decades. Widely practiced first-trimester screening and less extensively elevated midtrimester urine screening promise even greater accuracy than was available a decade ago. Recently, the combination of first- and second-trimester screening has been reported to enhance discrimination of the Down syndrome fetus from normal cases. Although the advances are welcome, they present the significant prospect of multiple competitive algorithms with the risk of confusing patients, practitioners, and health care planners. The need for reasonable consensus has never been more pressing.

Biomarkers↗
PubMed2004

Fetal Doppler velocimetry.

The introduction of new techniques for evaluating fetal status, particularly fetuses at theoretical risk for hypoxic ischemic encephalopathy, requires the most rigorous evaluation before widespread clinical deployment. The considerations extend beyond clinical value to the significant medicolegal implications of a failure to predict or ascertain compromise. The attitudes to clinical Doppler velocimetry have been shaped to a large extent by these practical concerns and the initial skepticism, which is a necessary component of scientific rigor. Available data strongly indicate, however, that in competent hands umbilical artery Doppler im-proves the clinical management of IUGR pregnancies. Failure to use Doppler may have the undesirable effect of increasing the risk of adverse outcome in the growth-restricted fetus. There is also strong evidence of benefit in the management of the Rh isoimmunization. Although numerous other clinical applications are on the horizon, much more information is needed to determine objectively the benefits and risks of these newer applications.

Blood Flow Velocity↗
PubMed2004

Biochemical screening for congenital defects.

This article discusses biochemical screening for congenital defects. Biochemical screening remains the standard for estimating the risk of aneuploidy in pregnancy. The combination of first and second trimester markers promises to further improve diagnostic accuracy for anomaly detection.

Abdominal Wall↗
PubMed2004

First trimester prenatal diagnosis.

PURPOSE OF REVIEW: The recent developments in first trimester sonography promise to greatly enhance our diagnostic capabilities for detection of aneuploidies. Collateral benefits of nuchal translucency measurements include the prediction of non-chromosomal adverse outcomes. These advances will fundamentally change clinical practices. All obstetricians must therefore have a working knowledge of the expanding literature in this field. RECENT FINDINGS: The review covers developments in nuchal translucency based first trimester detection of chromosomal anomalies and discusses the recent literature on the use of fetal nasal bone measurements to further improve diagnostic accuracy. Emerging data on the relationship between nuchal fluid measurement and the risk of cardiac anomaly will also be presented. SUMMARY: It is likely that the emphasis in obstetric clinical care will shift substantially towards the first trimester. With the enhanced diagnostic capabilities, greater research emphasis will inevitably need to be placed on the first trimester treatment of fetal disorders.

Aneuploidy↗
PubMed2003

Early second-trimester individualized estimation of trisomy 18 risk by ultrasound.

OBJECTIVE: To report two second-trimester ultrasound algorithms for trisomy 18 prediction. METHODS: Femur length, gross anomaly, choroid plexus cysts, two-vessel cord, and maternal age were documented in pregnancies undergoing genetic amniocentesis. Stepwise logistic regression was used to identify 1) the significant markers for predicting trisomy 18 when gross anomaly was not considered (algorithm 1) and 2) when gross anomaly was also considered (algorithm 2). Patient-specific risk was calculated based on the significant ultrasound markers plus maternal age. The diagnostic accuracy of each algorithm was determined. RESULTS: There were 1167 normal and 47 trisomy 18 cases. The mean gestational ages were 16.5 weeks (standard deviation [SD] 1.5) and 17.9 weeks (SD 1.6), respectively. Algorithm 1 consisted of maternal age, choroid plexus cyst, femur length, and two-vessel cord. The sensitivity and false positive rates were 61.7% and 1.5%, respectively, with an area under the receiver operating characteristics curve of 0.880 (P <.001). Algorithm 2 (age, femur length, gross anomaly, and choroid plexus cyst) had a sensitivity of 72.3% and false positive rate of 0.9% with an area under the curve of 0.956 (P <.001). Comparable detection rates were achieved in early gestation at up to and including 17.5 weeks (72.4% and 82.8%, algorithms 1 and 2, respectively, at a 4.0% false positive rate). CONCLUSION: The ultrasound markers were sensitive for trisomy 18 detection in the early second trimester.

Adult↗
PubMed2002

Early genetic sonogram for Down syndrome detection.

OBJECTIVE: The purpose of this study was to determine the Down syndrome sensitivity of early genetic sonography (14-<16 weeks of gestation) and to compare its diagnostic accuracy with that later in the mid trimester (16-24 weeks of gestation). STUDY DESIGN: Nuchal thickness, humerus and femur lengths, hyperechoic bowel, hypoplastic fifth digit (clinodactyly), and any gross anatomic defects were measured or ascertained in singleton pregnancies that were undergoing genetic amniocentesis. Multiple stepwise logistic regression analysis was used to determine the significant sonographic markers for Down syndrome detection in each group. Multivariate gaussian algorithms that included maternal age were used to estimate patient-specific Down syndrome risk. Sensitivity and false- positive rates, receiver-operating characteristic curves, and area under the curves were calculated and compared for both groups. RESULTS: There were 1,727 pregnancies with 22 Down syndrome fetuses (1.27%) in the early group versus 3,914 pregnancies with 86 Down syndrome fetuses (2.2%) in the later group. The mean +/- SD ages were 15.5 +/- 0.4 weeks versus 17.6 +/- 1.4 weeks, respectively. Early genetic sonography (14-<16 weeks) had a 100% detection rate, with a 21.2% false-positive rate. The early versus later genetic sonography had an 81.8% versus 61.6% detection rate, respectively, at a fixed 4.8% false-positive rate. Early sonography had significantly higher diagnostic accuracy (area under the curve, 0.962 vs 0.871, respectively; P =.005). In fetuses at 14 to 15 weeks, the genetic sonography was also highly accurate, with 100% detection with a 21.9% false-positive rate. CONCLUSION: Early genetic sonography is highly sensitive and statistically superior to later ultrasonography for Down syndrome detection. Early midtrimester sonography achieved a diagnostic accuracy similar to that currently reported for first-trimester nuchal translucency.

Adult↗
PubMed2002

Midtrimester nuchal thickness and the prediction of postnatal congenital heart defect.

OBJECTIVE: The study was performed to determine the sensitivity of nuchal thickness measurements for the detection of congenital heart defects (CHD) and to develop an algorithm for estimating patient-specific risk of CHD. STUDY DESIGN: Nuchal thickness measurements (expressed as multiples of the median) were obtained in 3,003 midtrimester fetuses in which postnatal evaluation of the heart was available. The sensitivity and false-positive rate of nuchal thickness threshold values for detecting CHD were used to calculate the area under the receiver operating characteristics curve. Stepwise logistic regression analysis was used to determine the significant predictors of heart defect among nuchal thickness and epidemiologic risk factors. Individual risk of CHD was calculated on the basis of background population risk of major CHD (estimated at 4.4 of 1,000) and the product of the likelihood ratios of the significant risk factors from the logistic regression. RESULTS: There were 95 cases of confirmed CHD. Nuchal thickness was statistically significant for the prediction of CHD with an area under the curve = 0.58, P =.01. Nuchal thickness and prior child with CHD were the only significant predictors among the multiple risk factors for this disorder. Patient-specific risk estimates for CHD based on these two "markers" were calculated. It was accurate and improved the prediction of CHD, area under the curve = 0.63, P <.001, compared with nuchal thickness alone. CONCLUSION: Midtrimester nuchal thickness measurement significantly detected postnatally confirmed CHD in chromosomally normal fetuses. We report for the first time a method for estimating individual patient risk of CHD.

Algorithms↗