Analysis of Fetal Palate to Assist Pre-natal Ultrasound

Cleft palate is one of the major facial congenital malformation in newborns. Pre-natal detection of this malformation is limited to detection of clefting of hard palate but isolated soft palate clefting still remains challenge for sonologists. As Indian literature is limited present study was attempted to provide dimensions and position of fetal palate by digitized images. To study dimensions, position and differences in parameters between second and third trimester fetuses. Median sagittal section of 32 formalin fixed fetuses was selected from the Department of Anatomy, St John's Medical College, Bangalore, Karnataka, India. Anatomical landmarks-The Nasion (N), Sellaturcica (S), Anterior Nasal Spine (ANS), Posterior Nasal Spine (PNS), tip of Uvula (U) were marked on sections. Length of hard palate (from ANS to PNS), Length of soft palate (from PNS to U), Hard palate/soft palate angle was defined. The anterior position of soft palate and its posterior position in relation to anterior cranial base were marked as N-S-PNS and N-S-U angle, respectively. The measurements were acquired directly from the digitized images using ImageJ software. Statistical analysis was done using SPSS 16. The mean values of ANS-PNS and PNS-U were 23.59±3.69mm and 14.39±2.70mm, respectively. The mean values of hard palate/soft palate angle, N-S-PNS and N-S-U angle were 144.720±11.11,51.150±9.09 and 93.370±9.58, respectively. Significant difference was noted between trimesters for length of hard and soft palate but not for palatal angles. During Pre-natal assessment of cleft palate, it is important for sonologist to keep in mind that the dimensions of palate proportionately increased in last two trimesters while the position remains constant.