OBJECTIVE: To evaluate ultrasound prenasal thickness (PT) as a way of enhancing the Down syndrome (DS) screening performance of second-trimester nasal bone (NB) length measurement. METHODS: Twenty-one DS and 500 normal fetuses were scanned at 14-27 weeks' gestation. The affected karyotype was known to the person performing the scan. Both PT and NB were measured in a mid-sagittal position and results were expressed in multiples of the normal gestation-specific median (MoM). Gaussian modelling was used to predict the performance of routine screening. RESULTS: Among DS fetuses, the PT median was 1.35 MoM, a highly statistically significant increase compared with the unaffected pregnancies (p < 0.0001, Wilcoxon Rank Sum Test, two-tailed). The NB median was 0.87 MoM (p < 0.0005) and the ratio PT/NB median was 1.51 MoM (p < 0.0001). In the normal fetuses, the two markers were positively correlated (0.25, p < 0.0001), whereas in the DS fetuses there was a non-significant negative correlation (-0.24, p = 0.33). For a 5% false-positive rate, the model predicted detection rate was 70% for PT and NB compared with 43% for NB alone. CONCLUSION: In the second trimester, PT is increased on average in DS fetuses. Combining PT and NB measurement could yield a higher screening detection rate than NB alone. Confirmation of our findings in a series of women scanned before the karyotype was known is needed before the method can be clinically implemented. Copyright 2005 John Wiley & Sons, Ltd.
OBJECTIVE: To evaluate ultrasound prenasal thickness (PT) as a way of enhancing the Down syndrome (DS) screening performance of second-trimester nasal bone (NB) length measurement. METHODS: Twenty-one DS and 500 normal fetuses were scanned at 14-27 weeks' gestation. The affected karyotype was known to the person performing the scan. Both PT and NB were measured in a mid-sagittal position and results were expressed in multiples of the normal gestation-specific median (MoM). Gaussian modelling was used to predict the performance of routine screening. RESULTS: Among DS fetuses, the PT median was 1.35 MoM, a highly statistically significant increase compared with the unaffected pregnancies (p < 0.0001, Wilcoxon Rank Sum Test, two-tailed). The NB median was 0.87 MoM (p < 0.0005) and the ratio PT/NB median was 1.51 MoM (p < 0.0001). In the normal fetuses, the two markers were positively correlated (0.25, p < 0.0001), whereas in the DS fetuses there was a non-significant negative correlation (-0.24, p = 0.33). For a 5% false-positive rate, the model predicted detection rate was 70% for PT and NB compared with 43% for NB alone. CONCLUSION: In the second trimester, PT is increased on average in DS fetuses. Combining PT and NB measurement could yield a higher screening detection rate than NB alone. Confirmation of our findings in a series of women scanned before the karyotype was known is needed before the method can be clinically implemented. Copyright 2005 John Wiley & Sons, Ltd.
Authors: Kjersti M Aagaard-Tillery; Fergal D Malone; David A Nyberg; T Flint Porter; Howard S Cuckle; Karin Fuchs; Lisa Sullivan; Christine H Comstock; George R Saade; Keith Eddleman; Susan Gross; Lorraine Dugoff; Sabrina D Craigo; Ilan E Timor-Tritsch; Stephen R Carr; Honor M Wolfe; Diana W Bianchi; Mary E D'Alton Journal: Obstet Gynecol Date: 2009-12 Impact factor: 7.661
Authors: Andrea Szabó; Károly Szili; János Tamás Szabó; János Sikovanyecz; Dóra Isaszegi; Emese Horváth; János Szabó Journal: Prenat Diagn Date: 2014-07-31 Impact factor: 3.050