Posterior Palatine Line: A Marker for Cleft Secondary Hard Palate

Abstract A cleft of the secondary palate (SP) can be isolated or associated with a cleft lip (CL). Although CL is relatively easy to detect by both 2D and 3D ultrasound, the detection of SP defects is still challenging. The posterior edge of the palatine bone forms the posterior border of the secondary hard palate (SHP). We evaluated the integrity of this posterior palatine bone by 2D ultrasound in an axial view. This posterior horizontal echogenic line of the hard palate (HP) is named the posterior palatine line. A defect in the middle of this line is considered a cleft of the SHP. We evaluated 1,450 midtrimester fetuses between December 2023 and June 2024 for the integrity of the posterior palatine line. Of these 1,450 fetuses, we found 12 fetuses with CL, CL and primary palate, CL with cleft SHP, and isolated cleft SHP. We detected a cleft in the posterior palatine line in 9 of 12 fetuses. The integrity of the palate was evaluated in 1,123 normal and 9 abnormal cases postnatally. This 2D view is easy to obtain and very useful for the detection of a cleft of the SHP. Visualization of the posterior palatine line in the routine midtrimester anomaly scan might enhance the detection rate of isolated cleft of the SHP.