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.