Three-dimensional ultrasonographic presentation of micrognathia.

OBJECTIVE To present the variable appearance of micrognathia in fetuses by three-dimensional ultrasonography and to describe practical methods for analysis of these volume data. METHODS Three-dimensional multiplanar imaging and surface-rendering techniques were used to show various syndromes and diagnostic approaches for the evaluation of fetal micrognathia. RESULTS Nine cases of fetal micrognathia are presented. Orthogonal multiplanar views were used to obtain a midsagittal facial profile. Examples of micrognathia include 3 cases of Pierre Robin sequence, cerebrocostomandibular syndrome, Cornelia de Lange syndrome, and hypochondrogenesis. Diagnostic pitfalls for micrognathia are also shown. CONCLUSIONS Three-dimensional multiplanar imaging increases the likelihood that a true midline sagittal view of the facial profile is being analyzed. Surface rendering provides another way to qualitatively evaluate the fetal chin from different viewing perspectives. Three-dimensional ultrasonographic methods are useful adjuncts to the preliminary diagnostic impression from two-dimensional ultrasonography.