Learning curve in measurement of fetal frontomaxillary facial angle at 11-13 weeks of gestation.

The article presents a study which identifies the number of ultrasound examinations needed in training sonographers to get an accurate measurement of the fetal frontomaxillary facial (FMF) angle in 11-13 week of gestation. Eight sonographers, accredited for nuchal translucency thickness (NT) measurement, were trained using three-dimensional (3D) ultrasound volumes in a case-by-case basis. Results showed that the competence in measuring FMF angle was obtained after 90 cases median number.