Diagnosis of fetal isolated cleft palate using assessment of the posterior hard palate angle.

Objective: The study aims to evaluate the role of the posterior hard palate angle in the prenatal diagnosis of cleft palate.

Study design: Stored images of the axial transverse view of the fetal secondary palate, obtained at three-level obstetric ultrasounds, were used to evaluate the posterior border of the hard palate. The study population comprised 63 consecutive pregnancies of unaffected cases and 17 pregnancies suspected for a cleft palate without cleft lip, including 7 cases of cleft palate, 4 cases of high-arched palate, and 6 false-positive cases.

Results: The posterior angle of the hard palate was significantly larger in the cleft palate group than in the healthy controls and false-positive cases: 227° (±51°) vs 160° (±16°), p < 0.0001; and 173° ± 18°, p < 0.0001, respectively. Regression analysis revealed that reflex angle remained an independent risk factor for cleft palate (odds ratio, 58.67 (95% confidence interval 10-341)). The sensitivity and specificity of the posterior angle assessment were 73% and 96%, respectively.

Conclusions: The posterior hard palate angle could be an ultrasound marker of cleft palate without a cleft lip.