Screening for trisomy 21 based on maternal age, nuchal translucency measurement, first trimester biochemistry and quantitative and qualitative assessment of the flow in the DV — the assessment of efficacy

Abstract

Objectives: The aim of the study was to compare effects of addition of two methods of ductus venosus (DV) flow assessment: qualitative -the assessment of shape of the A-wave (positive or negative), and quantitative -based on the pulsatility index for veins (DVPI) to the basic screening for trisomy 21 at 11 to 13 + 6 weeks of pregnancy. Material and methods:The ultrasound examination was performed in 8230 fetuses in singleton pregnancies at 11--13 + 6 wks, as a part of a routine screening for chromosomal defects. In DV A-wave was assessed and DVPI was calculated. After the scan blood sample was taken for first trimester biochemistry (BC). Risk for chromosomal defects was calculated and high-risk patients were offered an invasive test for karyotyping.Results: Basic screening with following combination of markers: MA, NT and BC provided lowest detection rate (DR) 87.50% for FPR = 6.94%. After adding qualitative DV A-wave assessment DR increased to 88.75% for FPR = 5.65%. The best DR = 93.75% for FPR = 5.55% was achieved when quantitative DVPI was added. The application of the Receiver Operating Curves curve confirmed validity of the addition of DV flow assessment to the screening model. The highest diagnostic power of the test was achieved when DVPI was added, with the ROC AUC of 0.974. Conclusions:The assessment of DV flow performed at 11-13 + 6 weeks increases DR for trisomy 21 and reduces FPR. The screening model based on the quantitative DV flow analysis (DVPI) gives better results compared to the qualitative flow assessment.

First trimester combined screening for fetal aneuploidies enhanced with additional ultrasound markers: an 8-year prospective study

“…Our median maternal age was 31 years, which was comparable to other values registered in Spain (32.4 years in 2016) [23], Romania (29.6 years in 2017) [18,24] or in Poland (34 years in 2017) [19], for first-trimester screening population.…”

“…Two other recent studies also reported similar detection rates [18,19] of 91.6% and 93.75%, respectively.…”

The Predictive Values of Ductus Venosus Pulsatility Index and ''A Wave'' for Chromosomal Abnormalities

“…27,28 The use of the quantitative DV flow (DV PIV) for screening trisomy 21 has been shown in recent literature to provide more accurate results compared to the qualitative flow assessment with a low positive predictive value. 6,16,29 By using the ROC curve, our study shows that abnormal DV blood flow was present in 61.5% fetuses with chromosomal abnormalities with 63.6% sensitivity, and specificity of 60.3%. A study by Bilardo et al found an abnormal DV PIV or an abnormal "a wave" in the DV waveform sensitivity of 65% for detecting chromosomal abnormalities.…”

The Relation of Ductus Venosus Pulsatility Index and Nuchal Translucency Thickness in a First-Trimester Sonographic Examination: A Matched Case-Control Study

“…4 Accumulating evidence indicates that the DV flow profile is the main cardiovascular imaging marker influencing prenatal risk stratification in terms of adverse pregnancy outcomes that would include chromosomal abnormalities and cardiac anomalies. 5,6 The DV connects the umbilical vein to the inferior vena cava, providing highly oxygenated blood for fetal circulation. 7 A Doppler examination of the DV is typically performed quantitatively for assessing parameters, such as the DV pulsatility index (DVPI; the most frequent measure), DV resistive index (DVRI), time-averaged maximum velocity (TAMAX), and the ventricular systole/atrial contraction ratio (S/A ratio), or qualitatively focusing on the a-wave.…”