Feasibility and Perception of Cross-sex Face Transplantation to Expand the Donor Pool

Abstract

Background: A major challenge in face transplantation (FT) is the limited donor allograft pool. This study aimed to investigate the feasibility of cross-sex FT (CSFT) for donor pool expansion by: (1) comparing craniomaxillofacial metrics following CSFT versus same-sex FT (SSFT); and (2) evaluating the public and medical professionals' perception of CSFT.

Methods: Seven cadaveric FTs were performed, resulting in both CSFT and SSFT. Precision of bony and soft tissue inset was evaluated by comparing pre- versus post-operative cephalometric and anthropometric measurements. Fidelity of the FT compared to the virtual plan was assessed by imaging overlay techniques. Surveys were administered to medical professionals, medical students, and general population to evaluate opinions regarding CSFT.

Results: Five CSFTs and 2 SSFTs were performed. Comparison of recipients versus post-transplant outcomes showed that only the bigonial and medial intercanthal distances were statistically different between CSFT and SSFT (P = 0.012 and P = 0.010, respectively). Of the 213 survey participants, more were willing to donate for and undergo SSFT, compared with CSFT (donate: 59.6% versus 53.0%, P = 0.001; receive: 79.5% versus 52.3%, P < 0.001). If supported by research, willingness to receive a CSFT significantly increased to 65.6% (P < 0.001). On non-blinded and blinded assessments, 62.9% and 79% of responses rated the CSFT superior or equal to SSFT, respectively.

Conclusions: Our study demonstrates similar anthropometric and cephalometric outcomes for CSFT and SSFT. Participants were more reticent to undergo CSFT, with increased willingness if supported by research. CSFT may represent a viable option for expansion of the donor pool in future patients prepared to undergo transplantation.

Fig. 1.

Computerized modeling using preoperative CT scan images of the donor and recipient. Cephalometric measurements can be obtained, as demonstrated here with the medial intercanthal distance (A). The preoperative CT scans data can be uploaded to the computerized surgical planning (CSP) software to determine the optimal osteotomy locations (B). Reprinted with permission from and copyrights retained by Eduardo D. Rodriguez, MD, DDS.

Fig. 2.

Bony parameters measured as visualized in frontal (left) and lateral (right) views. ANS, anterior nasal spine; MxPl, maxillary plane; PNS, posterior nasal spine. 1. Biparietal distance; 2. Lateral intercanthal distance; 3. Medial intercanthal distance; 4. Bizygomatic distance; 5. Bigonial distance; 6. Sella-nasion-A angle; 7. Sella-nasion-B angle; 8. Upper facial height; 9. Lower facial height; 10. Mandibular angle. Reprinted with permission from and copyrights retained by Eduardo D. Rodriguez, MD, DDS.

Fig. 3.

A comparison of the computerized surgical plan (CSP) and actual transplant outcomes. CSP demonstrating the planned skeletal subunit fixation at the nasofrontal, bilateral zygomatic, and genial segments (A) versus the actual outcomes (B). CT overlay techniques allow outcomes comparison by superimposition of the planned and actual craniofacial anatomy (C and D). Reprinted with permission from and copyrights retained by Eduardo D. Rodriguez, MD, DDS.

Fig. 4.

Image showing the survey excerpt. Participants were asked to rate the outcomes of various CSFTs and SSFTs. Only the blinded portion of the assessment is shown here. Reprinted with permission from and copyrights retained by Eduardo D. Rodriguez, MD, DDS.

Fig. 5.

A comparison of the computerized surgical plan with the actual positions of allograft skeletal segments after CSFT and SSFT. The predominance of green and yellow colors on craniofacial CT overlay and heat map analysis demonstrate high fidelity with the virtual plan, with discrepancies not exceeding 2 mm (bottom panel). Frontal view (B); ¾ views (A and C). Reprinted with permission from and copyrights retained by Eduardo D. Rodriguez, MD, DDS.

Fig. 6.

Participants’ willingness to donate and receive facial allografts. Participants expressed significantly increased willingness to receive a CSFT if further research supports it. Astersik (*) denotes statistical significance. Reprinted with permission from and copyrights retained by Eduardo D. Rodriguez, MD, DDS.

Fig. 7.

Participants’ ratings of cadaveric face transplants on a 5-point Likert scale. Astersik (*) denotes statistical significance. Reprinted with permission from and copyrights retained by Eduardo D. Rodriguez, MD, DDS.