3-D ultrasound of the fetal ear and fetal autosomal trisomies: a pilot study of a new screening protocol.

ABSTRACT

OBJECTIVE: We hypothesize that the rotation of the ear in fetuses with common autosomal trisomies will be markedly different from euploid fetuses and amenable to detection by 3-D ultrasound in the render mode. METHODS: Study participants (10 weeks 4 days through 19 weeks 0 days) underwent a 3-D rendering of the fetal face and ear along with other biometric measurements prior to invasive testing. RESULTS: Of the 348 patients who underwent chorionic villi sampling (CVS) (n = 208) or amniocentesis (n = 140), 18 were diagnosed with trisomy 21, 4 with trisomy 18, and 1 with trisomy 13. Mean gestational age was 12 weeks 6 days (range 10 weeks 6 days to 19 weeks 0 days). Ear angles were obtained in all cases; the time to obtain this angle ranged from 5 to 25 min. Thirty-two fetuses were found to have an abnormal ear angle with 23 of the 32 characterized by one of the aforementioned trisomies. CONCLUSIONS: These findings support the potential of this technique to provide valuable information in the identification of an increased-risk population. Prospective studies are needed to confirm the value of this screening modality as well as to assess its facility and ability to be incorporated into routine obstetrical practice.