Facial Transplantation: Surgical and Postoperative Care Explained

TL;DR: Facial transplantation is a complex, life-changing procedure for patients with severe facial deformities, aiming to restore both appearance and function. This article outlines the intricate surgical techniques involved in both donor harvest and recipient reconstruction, the critical lifelong immunosuppression required, and the extensive postoperative care, including infection prevention and psychological support. Patient selection is rigorous, considering not only the defect but also immunological and psychological factors. The ethical considerations and the detailed setup of a dedicated transplant program are also discussed, emphasizing the multidisciplinary effort required.

Understanding Facial Transplantation: Surgical and Postoperative Care

Facial transplantation is a rapidly evolving field in plastic surgery, with a limited but increasing number of procedures performed since 2005. This innovative surgery addresses severe facial destruction, often caused by ballistic traumas, burns, or animal bites, and goes beyond static reconstruction to restore dynamic function, communication capacity, and ultimately, social reintegration for patients. While the number of face transplants is still small, growing global expertise in composite tissue allotransplantation (CTA) helps answer complex questions regarding risks, benefits, indications, and technical, immunological, and ethical aspects.

The Evolution of Face Transplants

The journey of organ transplantation began with significant challenges, as early kidney, heart, and liver transplants often survived only weeks due to a lack of understanding of immunological rejection. Joseph Murray's pioneering work in immunology transformed the field. Early attempts at hand transplantation also failed because of inadequate immunosuppression. The introduction of cyclosporine in 1976, followed by agents like tacrolimus, mycophenolate mofetil, monoclonal antibodies, and antilymphocyte serum, revolutionized transplant survival by effectively preventing graft rejection with reduced toxicity.

Immunosuppression: A Lifelong Necessity

The human immune system's complexity means that transplanted skin, a highly immunogenic tissue, requires robust anti-rejection strategies. The standard immunosuppressive treatment for CTAs, including facial transplants, is designed for high immunological risk, similar to lung transplants. It combines an induction phase with antilymphocyte serum to lyse CD3+ T-lymphocytes responsible for acute cellular rejection, followed by maintenance therapy.

Standard Immunosuppressive Treatment

The current standard treatment begins with an induction phase using monoclonal or polyclonal antilymphocyte antibody, administered just after anastomosis in the operating room. This is followed by a tri-therapy regimen: mycophenolate mofetil (MMF), tacrolimus (FK506), and steroids. Precise monitoring is crucial postoperative:

Antilymphocyte serum requires daily CD3+ T-lymphocyte counts.
Tacrolimus (Prograf) needs blood levels between 10–15 ng/mL (target 5 ng/mL until D7, then 10–15 ng/mL during the first month).
Mycophenolate Mofetil (CellCept) requires repeated testing to estimate average concentration (AUC) in the range of 40–50 ng/mL.
Prednisolone/Prednisone is administered in decreasing doses post-surgery.

Acute rejection episodes are almost inevitable after the induction phase but are typically controlled with steroid boli. However, infections can trigger further rejection, requiring specific treatment.

Exploring Tolerance Induction

Beyond continuous immunosuppression, research aims at inducing tolerance, a state where the recipient's immune system recognizes the transplanted organ's antigens as its own. Pioneered by Starzl, this concept has animal models often involving radiation, which is not clinically viable. Newer human-applicable approaches include concomitant injection of donor hematopoietic stem cells. While myeloablative protocols (removing recipient bone marrow) are effective, they are too risky for functional transplants like CTAs due to potential Graft-versus-Host Disease (GVHD).

Nonmyeloablative protocols have shown success in animals, but human results are inconclusive. Some hypothesize that bone marrow within the donor's hand or mandible (vascularized bone) acts as a hematopoietic stem cell transplant, contributing to graft success. However, maxilla transplants, with less bone marrow, suggest this isn't universally the case. Subtle approaches focus on peripheral tolerance, such as Extracorporeal Chemophototherapy (ECP). ECP involves treating leukocyte cells with UVA radiation after leukapheresis and psoralen pretreatment. This induces apoptosis, leading to engulfment by macrophages or immature antigen-presenting cells in an anti-inflammatory environment, deleting effector T-cells and increasing regulatory T-cells, thus promoting allograft acceptance. ECP has been used for solid organ transplants to manage acute and chronic rejection.

Starzl's progressive approach to tolerance suggests immunomodulation with a rapid decline in anti-rejection treatment after induction, allowing controlled rejection episodes to stimulate regulatory cells and eventually achieve long-term immunological stability with low or no immunosuppression.

Immunological Compatibility and Monitoring

While facial transplants primarily require blood type compatibility, HLA matching can be crucial for sensitized patients (e.g., from blood transfusions or cadaveric skin grafts). Each screened patient undergoes anti-HLA serum tests every three months preoperatively. The appearance of HLA antibodies, even without a known transplant, can occur due to viruses mimicking HLA antigens, detectable by sensitive methods like Luminex. High levels of positive HLA antibodies may necessitate desensitization, though often inefficient. A negative virtual preoperative cross-match is mandatory, followed by a postoperative real cross-match. If the real cross-match is positive, specific treatment with anti-CD20 monoclonal antibody and immunoglobulin injections is administered to prevent humoral rejection.

Patient Selection for Facial Transplantation

Determining indications for facial transplantation is challenging, unlike hand transplants where the need for an organ replacement is clear. In facial transplants, patients often have severe disfigurements, but many could benefit from conventional autologous tissue reconstruction. The indication for a facial transplant is typically limited to cases with destruction of the orbicularis muscle (orbicularis oculi and/or orbicularis oris), which cannot be effectively reconstructed with autologous tissue.

Indications and Types of Facial Transplants

These destructive defects arise from various etiologies, including burns, ballistic traumas, animal bites, and tumors. While classifications exist, practical experience suggests that the indication is a complex combination of three elements: the defect, the patient, and the transplantation team.

Facial transplants can be categorized into:

Lower face transplant: Primarily for orbicularis oris destruction, often seen in ballistic traumas affecting the mouth and nose.
Upper face transplant: For orbicularis oculi destruction, common in burn patients, potentially combined with ears and nose.
Full face transplant: A combination of both upper and lower face defects.

Immunological and Psychological Considerations

The patient's suitability is not solely anatomical. Immunological aspects are vital; presensitization from blood transfusions or cadaveric skin grafts requires careful evaluation for HLA compatible donors. Psychological evaluation is paramount, often taking considerable time with patient hospitalization. Contraindications include psychological instability, borderline personalities, addiction, or any psychiatric disorder that might compromise the patient's capacity to understand and adhere to lifelong treatment. Nurses and assistant nurses play a crucial role in observing the patient's adaptive capacity. Paradoxically, patients with good pre-existing adaptive capacity tend to have the best outcomes.

Ethical Dimensions of Face Transplants

Informed consent is critical for such extreme surgery, ensuring the patient fully comprehends the risks and the necessity of lifelong treatment. Ethical questions arise for children, teenagers, and emergency cases. The concept of "free will" is often assessed using tools like the Time Trade-Off (TTO) and quality-of-life scales adapted for disfigured patients. Beyond individual patient considerations, the entire transplantation team must approve each case through multiple staff meetings. Rehearsals are mandatory to maintain teamwork and ensure logistical readiness.

Furthermore, the ethics of organ donation are central. Face donation is distinct from internal organ donation, as the face is fundamental to a person's identity and can impact the family's ability to accept death. Public awareness and careful donor restitution using a hard resin mask are essential to respect the deceased's human dignity and image. Failure to prioritize donor restitution could compromise public acceptance of both face transplant programs and organ donation in general.

The Surgical Journey: Harvesting the Donor Face

The face transplant harvest is a highly specialized procedure, always performed first on a heart-beating brain-dead donor. Prior to any harvest, a tracheotomy is performed, and an alginate mold of the donor's face is created to allow for post-harvest restitution. Harvesting on a beating heart minimizes warm ischemia time, which could compromise muscle function and immune impact.

Donor Preparation and Harvest Technique

We recommend a reproducible and standardized technique, typically harvesting a full face transplant and then removing unnecessary elements for the recipient. This approach simplifies donor reconstitution. The harvest is a lengthy procedure, and the head and neck region being in the operative field means anesthesiologists have limited access to the lower part of the donor, making simultaneous removal of other organs challenging. The harvested graft is washed with heparin-containing saline and transported in preservation solution in a standard icebox. After harvest, a hard resin mask, prepared during the operation, is fitted to the donor's face before returning the cadaver to the family.

Detailed Dissection for Facial Graft Procurement

The surgical drawing for a full face transplant extends from the scalp, behind the ears, and down to the neck, limited by the tracheotomy. The dissection begins in the neck, isolating the external jugular vein on both sides as low as possible. This allows access to deeper vessels, including the carotid artery and vein, which are followed upward. The thyrolingofacial trunk is isolated, requiring division of the hypoglossal nerve and the posterior digastric muscle. The facial nerve is approached via a parotidectomy route, dissected to its bifurcation, and transected at its exit from the stylomastoid foramen, with a 8-0 nylon stitch used for later identification on the recipient. To maximize nerve harvest, the external auricular conduit is transected. Pharyngeal and lingual arteries are divided, taking care not to cut the facial artery. The posterior auricular artery is raised with the flap for scalp blood supply.

If the scalp is included, a sagittal incision from the occipital area to the vertex allows for full scalp harvest. The scalp is dissected on a subperiosteal plane. The superficial temporalis pedicle can perfuse at least 80% of the scalp, and posterior auricular arteries are more critical than occipital arteries for scalp blood supply. If the scalp is not needed, a standard coronal approach is used. At this stage, the flap is held laterally by both maxillary arteries and veins, which are ligated near the temporomandibular joint to access the orbital region.

The dissection proceeds down to the levator muscle, which is divided after placing a 3-0 nylon stitch for repair. The flap is then raised anteriorly, following the masseter plane to the oral mucosa. This includes the facial nerve, parotid gland (with Stensen's duct), superficial and deep orbicularis oris, mental nerve, and most smile muscles (zygomaticus and levators). The dissection plane is subperiosteal along the mandible's horizontal branch, malar bone, and zygoma. The mental nerve is identified, and the entire cheek mucosa is harvested along the parotid ostium, leaving the buccal fat pad behind. On the maxilla and mandible, the mucosa is cut at the gingival level. The lateral canthus on each side is divided after inserting a 2-0 steel stitch for reinsertion. The eye conjunctiva is incised, and the lacrimal ducts are catheterized. The canthi and nasal bone are harvested via osteotomy, wider than a rhinoplasty osteotomy, to include the medial canthi, lacrimal duct, and sac. Infraorbital nerves are isolated and transected. If the maxilla or mandible is transplanted, the facial flap must remain attached to the bone for vascularization.

Finally, the flap, almost completely liberated, remains attached in the submental region. The submaxillary gland is harvested with the facial artery and vein. Concentration is maximal until the end to prevent pedicle injury. The transplant is then separated by dividing its blood supply (two external carotids and thyrolingofacial trunk), washed, and placed in organ preservation solution in an icebox. The lacrimal duct catheters are secured. For lower face transplants (e.g., ballistic trauma), the entire lower cosmetic unit is replaced. The flap drawing extends from the glabella, along the nose and infraorbital rim, to the helix root, then down the preauricular area, 5 cm below the mandibular angle, joining the opposite side above the tracheotomy. Osteotomy of the maxilla and mandible is performed after vascular dissection, ensuring bones remain attached to soft tissue for vascularization.

Recipient Surgery and Reconstruction

On the recipient side, all scarred tissue is debrided, carefully respecting cosmetic units to avoid a patchwork appearance. However, any remaining functional muscle should be preserved. A superficial parotidectomy is performed to identify and distinguish nerve branches for tension-free suture.

Anastomoses, Nerve Repair, and Bone Fixation

Arterial anastomoses are performed end-to-end on the external carotid artery.
Venous anastomoses are done end-to-end on the thyrolingofacial trunks and external jugular veins. In burn patients with no superficial veins, the thyrolingofacial trunk can be anastomosed end-to-side on the external jugular for full drainage.

After the first unilateral arterial anastomosis, the transplant is fully perfused. The second anastomosis is performed after nervous repair, proceeding from one side to the other. Motor nerves (facial nerve) are always sutured, ideally individually to prevent dyskinesia, but comprehensive dissection might risk temporal vessels in upper face transplants. Sensory nerves (infraorbital and mental nerves) are sutured only if available, which is impossible if they are included in transplanted bones.

Fibrin glue aids nerve suture and acts as a sealant to prevent postoperative hematoma. Bone fixation, when required, uses titanium plates and/or steel wire on the mandible and maxilla. This can be challenging due to donor-recipient discrepancies and may necessitate trimming for correct fixation. Mandibular transplants require careful preparation of the recipient remnant, possibly involving liberation of the masseter muscle or section of the temporal muscle tendon. All sutures and fixations are completed after unilateral venous and arterial anastomosis, with the second side done last. For eyelid transplantation, a dacryocystorhinostomy is created by drilling a hole in the nasal lateral wall, and lacrimal duct catheters are passed into the nose before bone suturing. The nasal bone is then fixed with a screw to position the medial canthi, and lateral canthi are fixed with steel wire. The surgery concludes with simple skin closure.

Postoperative Care and Recovery after Facial Transplantation

Postoperative care for facial transplant recipients is intensive and crucial for graft survival and patient well-being, focusing on infection prevention, complication management, and long-term follow-up.

Preventing and Managing Infections

Intercurrent infections, particularly cytomegalovirus (CMV), can trigger rejection episodes. Prophylaxis is essential:

Valganciclovir (900 mg/day for 6 months) is used for CMV-mismatch patients (D+, R-). CMV-compatible status is ideal.
Trimethoprim-sulfamethoxazole (400 mg/day for 6 months) prevents Pneumocystis carinii pneumonia.

Viral infections, especially CMV and human herpes simplex virus type 1, are reported more frequently in CTA recipients than in solid organ recipients. Bacterial infections are also a significant concern, particularly in burn patients with chronic, multi-resistant bacteria. Preoperative bacterial mapping and regular postoperative bacterial counting are recommended for specific prophylaxis and treatment.

Addressing Postoperative Complications

Like any microsurgical procedure, thrombosis is a critical risk, potentially leading to graft necrosis if untreated. Large vessel choice minimizes this risk, though recipient vessels might be compromised in multi-operated patients. Postoperative arterial control via simple Doppler is standard, but unilateral thrombosis can be difficult to detect clinically if the flap is still perfused by one pedicle. Any asymmetrical swelling warrants an echography and/or angioscanner. Venous thrombosis can occur due to tension; venous grafting or re-routing the cephalic vein may be necessary, followed by intravenous heparin. Psychiatric problems, such as confusion and agitation, can also occur postoperatively, potentially exacerbated by steroid use.

Long-Term Follow-up and Patient Well-being

Long-term follow-up is vital. CTAs are visible, allowing for easy clinical monitoring. Rejection is characterized by inflammation followed by a macular erythematous rash preceding necrosis. Graft inflammation necessitates biopsies to detect lymphocytic infiltration, using histological classifications like Banff or Kanitakis. Biopsies are taken from different skin and mucosa spots as rejection is not always uniform. Beyond clinical and histological follow-up, regular biological monitoring is essential to detect immunosuppressive treatment side-effects (e.g., diabetes, hypertension, chronic renal failure) and ensure patient compliance. Physical and speech therapy are crucial during reinnervation, typically taking 3–6 months for speech and lip movement improvement. Transplant recipients face an increased risk of cancer, primarily skin cancers, necessitating regular physical exams. Post-transplantation lymphoproliferative disease (PTLD) remains a major threat with high mortality if immunosuppression cannot be stopped, though not yet widely observed in CTA due to smaller patient numbers.

Some initially argued that the psychological trauma of face transplant would outweigh the benefits. However, this has been disproven; patients, already heavily disfigured with deep psychological scars, often find the surgery helps them overcome suffering. The key to accepting a patient is their psychological stability and adaptation capacity during evaluation, not the cause of disfigurement. Borderline or bipolar personalities are contraindications due to the necessity of lifelong treatment adherence. Patients paradoxically adapt immediately to their new faces, some even dreaming with their new appearance weeks after surgery. Psychological support remains important, akin to any major surgery requiring intensive care and prolonged hospitalization. Social reintegration, the ultimate goal, is directly correlated with cosmetic and functional outcomes.

Secondary Procedures and Revision Surgery

As with any complex reconstruction, secondary procedures may be necessary. These include dental implants, scar revision, skin excision, and liposuction. Such procedures should only be performed after evaluating potential local or general infection risks in immunosuppressed patients. Preoperative vascular evaluation with CT angioscanner is required due to modified anatomy. It's advisable to wait at least six months post-transplant as any surgery can trigger a rejection episode. Postoperative prednisolone injection helps prevent rejection and treat potential swelling.

Establishing a Facial Transplant Program

Setting up a facial transplant program is a lengthy and arduous process, involving intense collaboration across multiple specialties. The logistics are distinct from conventional plastic surgery:

Two teams (donor and recipient) are required, potentially operating in different locations.
The donor team must be proficient enough to perform harvests in any hospital.
Surgery cannot be scheduled, requiring constant readiness and efficient organization.
Specific materials must be stored for immediate transportation to harvest sites.
Strong cooperation with organ procurement agencies is essential.
Dialogue with other transplant teams fosters understanding of these high-risk procedures.

Conclusion

Facial transplantation is a testament to medical advancement, offering profound relief and restoring humanity to severely disfigured patients. This challenging field should be confined to specialized centers capable of ensuring the described complex medical, surgical, and ethical considerations. By giving life to years, these transplants push the ultimate frontier of plastic surgery, significantly improving patients' quality of life.

Facial Transplantation FAQ for Students

What is the primary goal of facial transplantation?

The primary goal of facial transplantation is to restore both the human appearance and dynamic function, which includes the capacity for communication and social reintegration, for patients suffering from severe facial destruction that cannot be adequately treated with conventional methods. It aims to go beyond static reconstruction to provide a more complete restoration of identity and quality of life.

Why is immunosuppression critical in facial transplantation?

Immunosuppression is critical because the recipient's immune system naturally recognizes the transplanted face as foreign tissue and would otherwise reject it. The skin, a highly immunogenic tissue, requires robust anti-rejection measures. Lifelong immunosuppressive therapy prevents this rejection, ensuring the long-term survival and function of the transplanted graft.

What are the key criteria for patient selection in facial transplant surgery?

Key criteria for patient selection involve a complex assessment of the defect, the patient's immunological profile, and their psychological stability. The defect must involve destruction of the orbicularis muscle (oculi and/or oris) that is beyond conventional reconstructive capabilities. Immunologically, presensitization (e.g., from transfusions) and HLA compatibility are evaluated. Psychologically, patients must demonstrate stability, adaptability, and the capacity to understand and adhere to lifelong treatment, ruling out conditions like borderline personality disorders or addiction.

How is donor face harvesting performed?

Donor face harvesting is a lengthy and complex procedure performed on a heart-beating brain-dead donor. It is typically the first tissue harvested. A tracheotomy and an alginate mold of the donor's face are created beforehand for post-harvest restitution. The surgeon performs detailed dissections to harvest vascularized soft tissue, nerves, and potentially bone (maxilla/mandible), ensuring precise identification and preparation of vessels and nerves for later anastomosis. After harvest, a hard resin mask is fitted to the donor's face to maintain dignity.

What are the main challenges in postoperative care?

The main challenges in postoperative care include preventing and managing infections (viral like CMV, bacterial), detecting and treating thrombosis (arterial or venous) which can lead to graft necrosis, and monitoring for side effects of lifelong immunosuppressive therapy such as diabetes, hypertension, and chronic renal failure. Psychological issues, though often less severe than anticipated, still require support. Additionally, long-term follow-up involves regular biopsies to monitor for rejection, physical and speech therapy for functional recovery, and screening for post-transplantation cancers.