A COMPARISON OF 2 CLASSIFICATION SYSTEMS FOR HEMIFACIAL MICROSOMIA

The classification of hemifacial microsomia (HFM) aids in diagnosis, t reatment planning, prognostic predictions and data evaluation. The aet iological and phenotypic heterogeneities of HFM, however, make its cla ssification problematic. This study used data from 50 patients to exam ine the classification of HFM and to compare two systems: OMENS and SA T. The results were concordant with current literature and demonstrate d the phenotypic heterogeneity of HFM. Essentially, both classificatio ns embody the major craniofacial defects, but the OMENS system appears to be further refined by its differentiation between soft tissue and nerve defects, and between orbital and mandibular defects. Neither sys tem, however, records deafness or grades auricular tags, although tags occurred in 34% of cases and two patients with otherwise 'normal' ear s had tags. Therefore, it is suggested that auricular tags be graded a s minor ear malformations. Furthermore, the OMENS system could be stre ngthened by the addition of an asterisk to the acronym in cases with s erious non-craniofacial anomalies, for example OMENS. This adds littl e complexity to the acronym, but immediately indicates when a patient' s features lie towards the more generalised oculoauriculovertebral end of the phenotypic spectrum.