No abstract

Three-dimensional US is useful to identify the location and extent of facial clefting. The advantages of 3D US are the following: (a) The face may be viewed in a standard orientation, (b) the defect may be viewed systematically by using an interactive display, and (c) the rendered image provides landmarks for the planar images. Patient decisions may be affected, since they can view the abnormality on a recognizable 3D rendered image.

The 3D US offered diagnostic advantages in about one-half of the selected cases studied and had effect on patient management in 5% of cases. This modality can be a powerful adjunctive tool to 2D US in providing a more comprehensible, 3D US impression of congenital anomalies. Thus, 3D US is currently most helpful as a targeted study complementing 2D US.

Seven cases with the pathologic/autopsy diagnosis of caudal regression or sirenomelia in which antenatal sonography had been performed were reviewed. The three patients with caudal regression had similar findings on antenatal sonogram, including normal or increased amniotic fluid, mild dilation or normal urinary systems, nonfused extremities, and sacral agenesis. In the four patients with sirenomelia, common sonographic findings included marked oligohydramnios, suspected renal agenesis, and sacral agenesis. A history of maternal diabetes was elicited in all patients with caudal regression and in none of the patients with sirenomelia. Findings confirm recent articles in pediatric pathology suggesting that caudal regression is a separate entity, distinct from sirenomelia.

In three of seven patients, 3D US provided additional information in the evaluation of skeletal dysplasias, as compared with 2D US.