The diagnosis of fetal micrognathia with two-dimensional and real-time three-dimensional color Doppler ultrasound.

Background: The study describes the diagnose of fetal micrognathia by the two-dimensional and real-time three-dimensional color doppler ultrasound, and evaluates its clinical value.

Methodology: The case group comprised 100 fetuses with highly suspected mandibular deformity, and the control group consisted of 100 normal fetuses. Various ultrasonic equipments and multimedia data processing system were used to obtain 2D and 3D images of fetal mandible, and the Biparietal Diameter (BPD) and Fetal Mandibular Longitudinal Diameter (FML) were measured. The Jaw Indices (JI) and Inferior Facial Angle (IFA) were calculated, and all suspected cases underwent chromosome examination. Eight confirmed cases of mandibular deformity were identified in the case group.

Results: This study examined eight cases of fetal micrognathia and found positive correlations between transverse diameters and FMLs of normal fetuses and gestational weeks. There was no significant correlation between JI, IFA, and gestational weeks. The study also compared JI, IFA, and FML between normal and small mandibular groups, finding significant differences. The smallest FML in the small mandibular group was only approximately equal to the normal fetus FML in the 18th week.

Conclusion: The study provides insights into the measurement and analysis of fetal micrognathia. Combining FML, JI, and IFA with ultrasonic diagnosis reduces fetal micrognathia misdiagnosis.