Facial Allograft Technique in Facial Reconstruction

Hospital of the University of Pennsylvania. Composite facial allografts have become increasingly popular in the reconstruction of complex facial defects. Good to excellent aesthetic results can be achieved, particularly when a foundation of donor skeleton has been transferred. A conventional craniofacial technique (monobloc osteotomy) can be used to transfer a thin monocortical foundation of bone, even in lieu of a skeletal defect, to improve the recipient periorbital and malar aesthetics.

Fig.1 Anteroposterior views of cadaver 1 and 2 before dissection.

Fig.2 Lateral views of cadaver 1 and 2 before dissection.

The monobloc osteotomy approach was used to obtain a full facial allograft and modified ex vivo to a thin monocortical layer and transferred to an anatomical facial skeleton. Named the “masque” flap because of the resemblance of the outline of the foundation of bone to a costume worn in masquerade balls.

Fig.3 Cadaver 1, bifrontal craniotomy markings, with scalp degloved to 1cm above the supraorbital rims.

Fig.4 Cadaver 1, lateral approach, with temporalis raised and zygomatic arch visible. Osteotomy of the lateral orbit, arch, and pterygomaxillary disjunction to be performed through this approach.

Fig.5 Cadaver 1, craniectomy removed. Markings anterior to the crista galli for modified monobloc approach. Cranialization was performed.

Fig.6 Cadaver 1, anteroposterior view of allograft (prethinning, with maxilla intact).

Fig.7 Cadaver 1, posteroanterior view, with vessels and nerves tagged.

Fig.8 Comparison of thickness of bone, before and after thinning with contouring burr.Bone thinned and maxilla removed, with thin unicortical foundation of bone in “masque-like” distribution.

Fig.9 Cadaver 2, posteroanterior view, with masque of bone outlined.

The masque flap was performed on two fresh-frozen cadavers.Thetotal time to harvest and thin the osteomyocutaneous flap was 155 minutes (30 minutes to modify it ex vivo). The average total surface area was 1060 cm2. Periorbital and malar ligaments were maintained, as was the integrity of the canthal tendons. The modified monobloc composite facial allograft technique allows transfer of a full facial allograft and maintains malar projection and excellent shape of the palpebral aperture.

Fig.10 Anatomical facial skeleton (recipient). Cadaver 1 allograft transferred, anteroposterior view (no sutures placed).

Fig.11 Cadaver 1 allograft, close-up view. Good malar projection and canthal integrity maintained before transfer to a recipient skeleton.

The use of cadaveric heads for dissection and documentation was approved by the Operational Committee of the Perelman School of Medicine Morgue before proceeding. A total of four dissections were performed.