The fetal profile line: a proposal for a sonographic reference line to classify forehead and mandible anomalies in the second and third trimester
Prenatal Diagnosis, 06/08/2012
de Jong–Pleij EAP et al. – Although large prospective studies are needed, the FP line may be a useful tool to detect second trimester profile anomalies such as retrognathia, sloping forehead and frontal bossing with the possibility of quantifying the latter.Methods
- Volumes of 248 normal and 24 pathological fetuses (16–36 and 19–37 weeks’ gestation, respectively) were analysed retrospectively.
- When the FP line passes anteriorly, across or posteriorly to the frontal bone, this was defined as ‘negative’, ‘zero’ or ‘positive’, respectively.
- When the FP line was positive the distance (F distance) between the FP line and the frontal bone was measured.
- No cases with a negative FP line were found in the normal fetuses. Before 27 weeks’ gestation the FP line was always ‘zero’ except in one case.
- After 27 weeks’ gestation the FP line was ‘positive’ in up to 25% (F distance (mean, range): 2.8, 2.1–3.6 mm).
- The FP line correctly identified 13 cases with retrognathia, 5 cases with frontal bossing and 3 cases with a sloping forehead.