LAUSR

BACKGROUND Prenatal diagnosis of cleft palate (CP) is challenging. The current study's objective was to investigate if prenatal alveolar cleft width is associated with the likelihood of a cleft of the secondary palate in unilateral cleft lip (CL). METHODS The authors reviewed 2D US images in fetuses with unilateral CL from 1/2012-2/2016. Images of the fetal face were obtained with a linear and/or curved probe in the axial and coronal planes. Measurements of the alveolar ridge gap were taken by the senior radiologist. Post-natal phenotype findings were compared with prenatal findings. RESULTS Thirty patients with unilateral CL met inclusion criteria; average gestational age was 26.67 ± 5.11 weeks (range 20.71, 36.57 weeks). Ten fetuses were found to have an intact alveolar ridge by prenatal US; postnatal exam confirmed intact secondary palate in all. Small alveolar defects <4 mm were noted in 3 fetuses; postnatal examination documented CP in a single patient. CP was confirmed in 15 of the remaining 17 fetuses who had alveolar cleft width >4 mm. An alveolar defect ≥ 4 mm on prenatal US was associated with greater likelihood of a cleft of the secondary palate (c 2 (2, n=30) = 20.23, p<.001). CONCLUSION In the setting of unilateral CL, prenatal US documentation of alveolar defects ≥4 mm are highly predictive of the presence of a cleft of the secondary palate. Conversely, an intact alveolar ridge is associated with an intact secondary palate.