Sonographical Integrated Test for Detection of Chromosomal Aberrations

Zusammenfassung

Ziel: Verschiedene Ultraschall- und biochemische Methoden werden zur Bestimmung des Risikos der chromosomalen Aberrationen benutzt. Das Ziel unserer Arbeit war die Schaffung eines diagnostischen Schemas von größter Sensitivität mithilfe eines Algorithmus, der die Ultraschallparameter beinhaltet. Material und Methoden: In einer Population von 1490 schwangeren Frauen wurde eine Ultraschalluntersuchung inklusive Nackentransparenz und Nasenbein im ersten Trimester durchgeführt. Im frühen zweiten Trimester wurde eine weitere Ultraschalluntersuchung mit der Messung von Nackentransparenz und Nasenbein vorgenommen. Ergebnisse: Eine Kombination von NT- und NB-Messung zeigte die größte Sensitivität (94,7 %), Spezifität (99,21 %), PPV (85,7 %) und NPV (99,73 %). Schlussfolgerung: Der vorgeschlagene Test ist charakterisiert durch einen hohen prädiktiven Wert für die Entdeckung der chromosomalen Aberrationen, niedrige Ausführungskosten sowie absolute Sicherheit für den Fetus und er kann allen schwangeren Frauen angeboten werden. Diese Kombination von 2 Ultraschalluntersuchungen erhöht die Wertigkeit des Testes erheblich.

Abstract

Purpose: Different sonographical and biochemical methods for the detection of an elevated risk of chromosomal abnormality are used. The aim of our study was to establish a diagnostic scheme with the highest sensitivity by means of an algorithm incorporating all parameters. Materials and Methods: In a group of 1490 pregnant women, ultrasound examination including nuchal translucency and nasal bone measurement was performed in the first trimester. Then, in the early second trimester, a second ultrasound examination combined with measuring nuchal thickness and nasal bone was carried out. Results: The combination of the NT and NB measurement showed the highest sensitivity (94.7 %), specificity (99.21 %), PPV (85.7 %) and NPV (99.73 %). Conclusion: The proposed integrated test is characterised by a high predictive value for the detection of chromosomal abnormalities, low cost of performance and absolute safety for the foetus and could be offered to all pregnant women. The combination of two ultrasound examinations and biochemistry greatly increased the value of the test.

Key words

nuchal translucency - ultrasound 2D - chromosomal aberration - Down syndrome - screening

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