Identity transfer and identity restoration in facial allotransplantation

Facial allotransplantation is fast becoming a reconstructive option for severely disfigured individuals, but it is still in experimental stage. Facial allotransplantation will be considered fully ethical only when it addresses the recipient's identity concerns. There exist no such studies that quantify and predict identity changes following change in geometry of underlying facial skeleton and overlying soft tissue morphology. I objectively address these identity concerns in the present study.

Using software (Mimics version 14.0, Materialise, Plymouth, Michigan), I developed 3-dimensional facial models from the computed tomographic images of 4 identical and 1 nonidentical twin pairs. On the basis of cranial base anatomy, 3-dimensional coordinate values of selected landmark locations were measured (Surgicase, Materialise, Plymouth, Michigan) and a morphometric method was applied to quantify identity differences between them. Identity parameters were drawn on a diagrammatic chart that depicted the biophysical identity range. Using software (Mimics version 14.0), facial allotransplant simulation was done involving most of the nasal bone, maxilla, and zygoma. Morphological parameters of resulting new identity were drawn on diagrammatic chart and if they fell within the chart, facial allotransplantation resulted in identity transfer. Moreover, a scale was used to quantify identity transfer and identity restoration resulting from facial allotransplantation.

Identity changes of facial allotransplantation are objectively quantified that can be used as a communication tool in consent taking process.

My findings suggest that donor facial allograft may be identified on the recipient's face depending upon underlying craniofacial morphology and accordingly, identity changes can be suitably predicted.