**3. The ear**

The most frequent clinical characteristic in diagnosing the Down syndrome has been the short ear length. Sonographic studies implied that measurements of the short ear length could be a useful predictor of fetal anomalies. In late gestation, important details of the anatomy of the external ear became accessible. In good conditions for scanning, and using high-resolution systems, the helix, scaphoid fossa, triangular fossa, concha, antihelix, tragus, antitragus, intertragic incisure, and lobule are sometimes visualized [21].
