Measurement of nuchal volume in the first trimester Down screening using three-dimensional ultrasound.
OBJECTIVE
Screening of fetuses at 11 to 14 weeks of gestation for Down syndrome using stored volumes acquired by a three-dimensional (3D) scanner.


METHODS
Thirty-four healthy singleton fetuses were recruited consecutively and prospectively during routine first trimester scans in our unit. Two-dimensional (2D) images of nuchal translucency (NT), crown-rump length (CRL), and biparietal diameter (BPD) were obtained by following a standard protocol. The volume of the nuchal area (NV) was obtained by a 3D scanning machine.


RESULTS
The mean time to perform a 2D first trimester scan was 15.3 min, while the mean time to obtain and examine the stored volumes was 11.1 min (p<0.001) in a 3D scan. There were no significant differences in NT, CRL, and BPD between the two groups. Two cases with an NT thickness>2.5 mm also revealed increased volume data in the nuchal area. The Pearson's correlations between NT and CRL, BPD and CRL, NT and NV, and NV and CRL were moderate-to-high positive.


CONCLUSIONS
The nuchal volume data and the standard curve in the first trimester may be possible markers for Down syndrome screening. 3D scans can also minimize the scanning time, providing views not easily following strict NT guidelines.
Shaw
Sheng-Wen
SW
Department of Obstetrics and Gynecology, Linkou Medical Center, Chang Gung Memorial Hospital, and Chung Gung University College of Medicine, Taoyuan, Taiwan.
Hsieh
T'sang-T'ang
TT
Hsu
Jenn-Jeih
JJ
Lee
Chyi-Long
CL
Cheng
Po-Jen
PJ
D015331:Cohort Studies; D004314:Down Syndrome / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D021621:Imaging, Three-Dimensional; D048208:Nuchal Translucency Measurement / Q000379:methods*; D010865:Pilot Projects; D011247:Pregnancy; D011261:Pregnancy Trimester, First