The aim of this study was to assess conventional two-dimensional (2D) ultrasound enhanced with a three-dimensional (3D) ultrasound technique, the 'reverse-face' view (3D-RF) in prenatal evaluation of the involvement of the lips, alveolar ridge and secondary palate in suspected isolated orofacial clefting.
One hundred and twenty-four cases of suspected orofacial clefting diagnosed by a routine 2D ultrasound scan were referred for specialist ultrasound at 20-34 weeks' gestation for a detailed assessment of the lips and palate using both 2D and 3D ultrasound. For the 3D examination the lips and alveolar ridges were examined both in profile and in the frontal plane. The palate was then assessed in the reverse coronal view by rotating the face through 180° on the vertical axis to produce the 3D-RF view. Antenatal diagnoses were compared with postnatal findings. Left and right lip and alveolar ridge defects were counted separately according to the Kernohan 'striped Y' classification.
Of 124 patients, 110 had isolated facial clefts and were available for follow-up; in 10, 3D-RF views were not successfully obtained, leaving 100 cases for assessment. The sensitivity of the 2D enhanced with 3D-RF technique for the diagnosis of cleft of the lip was 116/122 (95%), false-positive rate (FPR) 7.7%; for alveolar ridge was 87/103 (84.5%), FPR 7.2%; and for hard palate was 61/68 (89.7%), FPR 15.6%.
The data reported represent the largest series of orofacial abnormalities diagnosed by 2D ultrasound and enhanced with 3D imaging to refine the detection of clefts of the hard palate. The technique is feasible in 90% of patients in whom almost 90% have a correct classification of clefts of the lip, alveolar ridge and palate.