Heterotopic transplantation of total face/scalp flap

Abstract

There are various conventional techniques for the reconstruction of the face and scalp region following severe face and scalp deformities caused by extensive tumor ablation, thermal or chemical burns or mechanical trauma. Traditional reconstructive alternatives include skin grafts, local flaps, free-tissue transfers, and prefabricated flaps used in combination with tissue expansion techniques. Despite the use of meticulous techniques and artistic creativity, full functional and aesthetic reconstruction is challenging and can rarely be achieved. When the autogenous tissues are not available or not good enough for the reconstruction of the face and scalp region, allogeneic tissues or organs from cadaveric sources may serve as a reconstructive option. But there may a risk of acute or subacute rejection which may be catastrophic.

In an attempt to mimic the clinical scenario of a babysitter procedure we developed an experimental model of the heterotopic total face/scalp transplantation model in rats.

A total of 32 animals were studied in three experimental groups. In groups I and II non-vascularized isogeneic and allogeneic total heterotopic face/scalp flap transplantations were performed. In group III vascularized allogeneic total heterotopic face/scalp flap transplantation was accomplished. To prevent acute and chronic allograft rejection, Cyclosporine-A (16 mg/kg per day) therapy was initiated 24 h after transplantation in the allotransplantation groups and the dose was tapered to 2 mg/kg per day within 4 weeks and was maintained at that level thereafter.

In the control group with non-vascularized transplants (group I and II), flap necrosis within 5–7 days after transplantation was observed in all transplants. Long-term survival (>400 days) was achieved, without any signs of rejection, with low-dose (2 mg/kg per day) cyclosporine A therapy in group III. This is the first report documenting successful heterotopic composite total face/scalp flap allotransplantation in the rat model.