title: The Effect of Ethnicity on 2D and 3D Frontomaxillary Facial Angle Measurement in the First Trimester.
abstract: Objectives. To determine the existence and extent of ethnic differences in 2D or 3D fetal frontomaxillary facial angle (FMFA) measurements. Methods. During routine 11-14 weeks nuchal translucency screening undertaken in a private ultrasound practice in Sydney, Australia, 2D images and 3D volumes of the fetal profile were collected from consenting patients. FMFA was measured on a frozen 2D ultrasound image in the appropriate plane and, after a delay of at least 48 hours, was also measured on the reconstructed 3D ultrasound volume offline. Results. Overall 416 patients were included in the study; 220 Caucasian, 108 north Asian, 36 east Asian and 52 south Asian patients. Caucasians had significantly lower median FMFA measurements than Asians in both 2D (2.2°; P < 0.001) and 3D (3.4°; P < 0.001) images. Median 2D measurements were significantly higher than 3D measurements in the Caucasian and south Asian groups (P < 0.001 and P = 0.04), but not in north and east Asian groups (P = 0.08 and P = 0.41). Conclusions. Significant ethnic variations in both 2D and 3D FMFA measurements exist. These differences may indicate the need to establish ethnic-specific reference ranges for both 2D and 3D imaging.
authors.affiliation: The University of Sydney, Faculty of Health Sciences, P.O. Box 170, Lidcombe, NSW 1825, Australia ; Sydney Ultrasound for Women, Suite 114, Level 1, Q Central, 10 Norbrik Drive, Bella Vista, NSW 2153, Australia.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Alphonse
authors.forename: Jennifer
authors.initials: J
authors.lastname: Cox
authors.forename: Jill
authors.initials: J
authors.lastname: Clarke
authors.forename: Philip
authors.initials: P
authors.lastname: Schluter
authors.forename: Andrew
authors.initials: A
authors.lastname: McLennan