Anthropometric Facial Measurements for Predicting Donor-to-Recipient Suitability in Face Transplantation

Purpose:

Fast, inexpensive, and reproducible methods predicting donor-recipient match in face transplant patients would be useful. Anthropometric landmarks of recipients and potential donors can be easily measured,^1,2 and may provide the opportunity to better match individuals before face transplantation.³ Virtual face transplantation allows us to perform these measurements and assess donor-to-recipient compatibility in larger numbers and more ethically and feasibly than via real-life transplantation.^4,5

Methods:

Sixty-one three-dimensional (3-D) virtual face transplantations (VFTs) were performed with Surgicase CMF surgical planning software using reconstructed high-resolution computed tomography (CT) angiographs of varying ages and genders. Corresponding portions of donor 3-D models were transplanted to fill specific facial defects that were created in recipient 3-D models. Twenty independent reviewers then evaluated the level of disfigurement of the resulting post-transplant 3-D model. A total of 9 soft tissue measurements were taken from each of the VFT donor and recipient pre-transplant 3-D model using Dolphin Imaging Software. The absolute difference in measurement from the pair was correlated to the resulting degree of disfigurement after virtual face transplant through a univariate logistic regression model.

Results:

Five soft-tissue measurements were predictive of transplants being rated ‘very disfigured’ compared those rated as ‘normal’ or ‘mildly disfigured,’ and were as follows: trichion to nasion facial height (odds ratio 1.106, 95% confidence interval: 1.066-1.148),  endocanthal width (OR 1.096, CI: 1.051-1.142), exocanthal width (OR 1.067, 95% CI: 1.036-1.099), mouth/chelion width (OR 1.064, 95% CI: 1.019-1.110), and subnasale to menton facial height (OR 1.029, CI: 1.003-1.056).   

Conclusions:

The following study provides early evidence for the importance of soft tissue measurements in planning of facial transplantation.  With future improvements to immune suppression and increased donor availability, matching on soft-tissue landmarks may be an additional factor used to optimize post-transplant outcome.