The application of the multi-slice CT based OMENS classification in diagnosing pediatric hemifacial microsomia

Objective: To assess the value of the multi-slice CT based OMENS classification in diagnosing pediatric hemifacial microsomia. Methods: Eleven patients including 9 boys and 2 girls with suspicion of hemifacial microsomia underwent MSCT. Multi-planar reformation (MPR), maximum intensity projection (MIP) and volume-rendered image (VR) reconstruction were performed at the workstation. The malformations of the facial structures were analyzed respectively with the OMENS classification system. Results: On CT reconstruction images, hemifacial microsomia in all 11 patients was demonstrated clearly. Nine patients were found to have unilateral lesion, including 6 on the left side and 3 on the right side. Two patients presented bilateral involvement with various severity degree. The OMENS classification system can be perfectly used to analyze the deformities. Respectively, the orbit and zygomatic arch deformity involved 8 sides in 8 cases, the mandible deformity involved 10 sides in 9 cases, the auricular deformity involved 13 sides in 11 cases, and the soft tissue deformity involved 12 sides in 11 cases. Conclusion: MSCT based OMENS classification system can make accurate and comprehensive evaluation of the morphological changes in hemifacial microsomia, which provide strong imaging evidence to clinical evaluation. (authors)