Three-dimensional Ultrasonographic Presentation of Micrognathia

Objective. To present the variable appearance of micrognathia in fetuses by three-dimensional ultra-sonography 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, cerebrocosto-mandibular syndrome, Cornelia de Lange syndrome, and hypochondrogenesis. Diagnostic pitfalls for micrognathia are also shown. Conclusions. Three-dimensional multiplanar imaging increases the like-lihood that a true midline sagittal view of the facial profile is being analyzed. Surface rendering pro-vides another way to qualitatively evaluate the fetal chin from different viewing perspectives. Three-dimensional ultrasonographic methods are useful adjuncts to the preliminary diagnostic impres-sion from two-dimensional ultrasonography. Key words: fetus; micrognathia; prenatal diagnosis; three-dimensional ultrasonography